26.1.2

- Breaking change: `c:tools/spear` has been renamed to `c:tools/trident` to match other loaders
- The contents of the `c:tools/melee_weapon` tag now includes spears

.gitattributes

@@ -3,6 +3,7 @@
 *.patch text eol=lf
 *.java text eol=lf
 *.gradle text eol=crlf
+**/MANIFEST.MF text eol=crlf
 *.png binary
 *.gif binary
 *.exe binary
@@ -21,3 +22,6 @@ src/generated/**/*.json text eol=lf
 src/generated_test/**/.cache/cache text eol=lf
 src/generated_test/**/*.json text eol=lf
 
+# We force eclipse to use unix line endings
+ide/eclipse/template/.settings/*.prefs text eol=lf
+

.github/ISSUE_TEMPLATE/feature_request.md

@@ -10,4 +10,4 @@ assignees: ''
 <!-- Please note, feature requests that are submitted as GitHub issues here are rarely implemented. -->
 <!-- If you'd like to see something in Forge, you should be ready to implement it as a PR. -->
 <!-- If you're not sure, open a Draft PR or discuss it in the Discord server. -->
-<!-- Discord: https://discord.gg/UvedJ9m -->
+<!-- Discord: https://discord..minecraftforge.net/ -->

.github/ISSUE_TEMPLATE/issue_report.md

@@ -11,6 +11,7 @@ assignees: ''
 
 <!-- For support with crashes and issues, please create a post on the forum instead: -->
 <!-- https://www.minecraftforge.net/forum/forum/18-support-bug-reports/ -->
+<!-- You can also use the discord for support, https://discord.minecraftforge.net/ -->
 
 **Minecraft Version:** {Minecraft version}
 

.github/support.yml

@@ -1,16 +0,0 @@
-# Configuration for support-requests - https://github.com/dessant/support-requests
-
-# Label used to mark issues as support requests
-supportLabel: Forum
-# Comment to post on issues marked as support requests. Add a link
-# to a support page, or set to `false` to disable
-supportComment: >
-  👋 We use the issue tracker exclusively for final bug reports and feature requests.
-  However, this issue appears to be better suited for the
-  [Forge Support Forums](http://www.minecraftforge.net/forum/forum/18-support-bug-reports/).
-  Please create a new topic on the support forum with this issue, and the conversation can
-  continue there.
-# Whether to close issues marked as support requests
-close: true
-# Whether to lock issues marked as support requests
-lock: true

.github/workflows/comments.yml

@@ -0,0 +1,16 @@
+name: 'Comment actions'
+
+on: issue_comment
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/comment_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.github/workflows/issues.yml

@@ -0,0 +1,16 @@
+name: 'Issue actions'
+
+on: issues
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/issue_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.github/workflows/publish.yml

@@ -0,0 +1,28 @@
+name: Publish
+
+on:
+  push:
+    branches: [ '26.1.2' ]
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    uses: MinecraftForge/SharedActions/.github/workflows/gradle.yml@main
+    with:
+      java: 21
+      gradle_setup: './gradlew setup'
+      gradle_tasks: 'build publish'
+      artifact_name: 'forge'
+    secrets:
+      DISCORD_WEBHOOK: ${{ secrets.DISCORD_WEBHOOK }}
+      PROMOTE_ARTIFACT_WEBHOOK: ${{ secrets.PROMOTE_ARTIFACT_WEBHOOK }}
+      PROMOTE_ARTIFACT_USERNAME: ${{ secrets.PROMOTE_ARTIFACT_USERNAME }}
+      PROMOTE_ARTIFACT_PASSWORD: ${{ secrets.PROMOTE_ARTIFACT_PASSWORD }}
+      MAVEN_USER: ${{ secrets.MAVEN_USER }}
+      MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
+      SIGN_KEY_ALIAS: ${{ secrets.SIGN_KEY_ALIAS }}
+      SIGN_KEY_PASSWORD: ${{ secrets.SIGN_KEY_PASSWORD }}
+      SIGN_KEYSTORE_PASSWORD: ${{ secrets.SIGN_KEYSTORE_PASSWORD }}
+      SIGN_KEYSTORE_DATA: ${{ secrets.SIGN_KEYSTORE_DATA }}

.github/workflows/pull_request_review.yml

@@ -0,0 +1,13 @@
+name: 'PR Review'
+
+on: pull_request_review
+
+jobs:
+  upload_payload:
+    name: Upload payload
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/upload-artifact@v4 # Payload artifact is consumed in Actionable
+        with:
+          name: payload
+          path: ${{ github.event_path }}

.github/workflows/pull_request_review_comment.yml

@@ -0,0 +1,13 @@
+name: 'PR Review Comment'
+
+on: pull_request_review_comment
+
+jobs:
+  upload_payload:
+    name: Upload payload
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/upload-artifact@v4 # Payload artifact is consumed in Actionable
+        with:
+          name: payload
+          path: ${{ github.event_path }}

.github/workflows/pull_request_review_comment_run.yml

@@ -0,0 +1,20 @@
+name: 'Pull Request Review Comment actions'
+
+on:
+  workflow_run:
+    workflows: [PR Review Comment]
+    types:
+      - completed
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/pr_review_comment_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.github/workflows/pull_request_review_run.yml

@@ -0,0 +1,20 @@
+name: 'Pull Request Review actions'
+
+on:
+  workflow_run:
+    workflows: [PR Review]
+    types:
+      - completed
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/pr_review_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.github/workflows/pull_requests.yml

@@ -0,0 +1,18 @@
+name: 'Pull Request actions'
+
+on:
+  pull_request_target:
+    types: [assigned, unassigned, labeled, unlabeled, opened, edited, closed, reopened, synchronize, converted_to_draft, ready_for_review, locked, unlocked, review_requested, review_request_removed, auto_merge_enabled, auto_merge_disabled]
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/pr_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.github/workflows/push.yml

@@ -0,0 +1,16 @@
+name: 'Push actions'
+
+on: push
+
+permissions:
+  contents: read
+  issues: write
+  pull-requests: write
+  discussions: write
+
+jobs:
+  labels:
+    uses: MinecraftForge/SharedActions/.github/workflows/push_actions.yml@main
+    secrets:
+      GH_APP_KEY: ${{ secrets.GH_APP_KEY }}
+      GH_APP_NAME: ${{ secrets.GH_APP_NAME }}

.gitignore

@@ -13,6 +13,9 @@
 /classes
 *.iml
 
+# We however WANT the ide folder as it has tempaltes/configs for developing Forge.
+!ide/**
+
 #gradle
 /build
 /.gradle
@@ -23,8 +26,6 @@
 /projects/mcp/
 /projects/clean/
 /projects/forge/
-/projects/fmlonly/
-#/patches/*
 
 #occupational hazards
 /projects/**/build/
@@ -32,16 +33,17 @@
 /projects/**/run/
 /projects/**/*.launch
 /repo/
-src/generated/resources/.cache/
+src/*/generated/**/.cache/
 
-#Patch rejects
-/patches-/
-*.patch.rej
-/projects/*/rejects/
+# Generated by gradle every import
+**/src/main/resources/META-INF/MANIFEST.MF
+/fmlloader/src/main/resources/forge_version.json
 
-# FML changelog
-changelog.txt
-*.py
-*.7z
-/logs/
+/ForgeRoot.ipr
+/ForgeRoot.iws
 
+# APT stuff
+/*/.gitignore
+/*/.factorypath
+/*/.apt_generated/
+/fmlcore/logs/

CREDITS.txt

@@ -1,65 +0,0 @@
-Minecraft Forge: Credits/Thank You
-
-Forge is a set of tools and modifications to the Minecraft base game code to assist 
-mod developers in creating new and exciting content. It has been in development for 
-several years now, but I would like to take this time thank a few people who have 
-helped it along it's way.
-
-First, the people who originally created the Forge projects way back in Minecraft 
-alpha. Eloraam of RedPower, and SpaceToad of Buildcraft, without their acceptiance 
-of me taking over the project, who knows what Minecraft modding would be today.
-
-Secondly, someone who has worked with me, and developed some of the core features
-that allow modding to be as functional, and as simple as it is, cpw. For developing
-FML, which stabelized the client and server modding ecosystem. As well as the base
-loading system that allows us to modify Minecraft's code as elegently as possible.
-
-Mezz, who has stepped up as the issue and pull request manager. Helping to keep me
-sane as well as guiding the community into creating better additions to Forge.
-
-Searge, Bspks, Fesh0r, ProfMobious, and all the rest over on the MCP team {of which 
-I am a part}. For creating some of the core tools needed to make Minecraft modding 
-both possible, and as stable as can be.
-  On that note, here is some specific information of the MCP data we use:
-    * Minecraft Coder Pack (MCP) *
-      Forge Mod Loader and Minecraft Forge have permission to distribute and automatically 
-      download components of MCP and distribute MCP data files. This permission is not 
-      transitive and others wishing to redistribute the Minecraft Forge source independently
-      should seek permission of MCP or remove the MCP data files and request their users 
-      to download MCP separately.
-      
-And lastly, the countless community members who have spent time submitting bug reports, 
-pull requests, and just helping out the community in general. Thank you.
-
---LexManos
-
-=========================================================================
-
-This is Forge Mod Loader.
-
-You can find the source code at all times at https://github.com/MinecraftForge/MinecraftForge/tree/1.12.x/src/main/java/net/minecraftforge/fml
-
-This minecraft mod is a clean open source implementation of a mod loader for minecraft servers
-and minecraft clients.
-
-The code is authored by cpw.
-
-It began by partially implementing an API defined by the client side ModLoader, authored by Risugami.
-http://www.minecraftforum.net/topic/75440-
-This support has been dropped as of Minecraft release 1.7, as Risugami no longer maintains ModLoader.
-
-It also contains suggestions and hints and generous helpings of code from LexManos, author of MinecraftForge.
-http://www.minecraftforge.net/
-
-Additionally, it contains an implementation of topological sort based on that 
-published at http://keithschwarz.com/interesting/code/?dir=topological-sort
-
-It also contains code from the Maven project for performing versioned dependency
-resolution. http://maven.apache.org/
-
-It also contains a partial repackaging of the javaxdelta library from http://sourceforge.net/projects/javaxdelta/
-with credit to it's authors.
-
-Forge Mod Loader downloads components from the Minecraft Coder Pack
-(http://mcp.ocean-labs.de/index.php/Main_Page) with kind permission from the MCP team.
-

Jenkinsfile

@@ -1,125 +0,0 @@
-@Library('forge-shared-library')_
-
-pipeline {
-    options {
-        disableConcurrentBuilds()
-    }
-    agent {
-        docker {
-            image 'gradle:7-jdk16'
-            //args '-v forgegc:/home/gradle/.gradle_cache/'
-        }
-    }
-    environment {
-        GRADLE_ARGS = '--no-daemon --console=plain' // No daemon for now as FG3 kinda derps. //'-Dorg.gradle.daemon.idletimeout=5000'
-        DISCORD_WEBHOOK = credentials('forge-discord-jenkins-webhook')
-        DISCORD_PREFIX = "Job: Forge Branch: ${BRANCH_NAME} Build: #${BUILD_NUMBER}"
-        JENKINS_HEAD = 'https://wiki.jenkins-ci.org/download/attachments/2916393/headshot.png'
-    }
-
-    stages {
-        stage('notify_start') {
-            when {
-                not {
-                    changeRequest()
-                }
-            }
-            steps {
-                discordSend(
-                    title: "${DISCORD_PREFIX} Started",
-                    successful: true,
-                    result: 'ABORTED', //White border
-                    thumbnail: JENKINS_HEAD,
-                    webhookURL: DISCORD_WEBHOOK
-                )
-            }
-        }
-        /*
-        stage('pull_cache') {
-            steps {
-                sh 'cp -r /home/gradle/.gradle_cache/jdks/ /home/gradle/.gradle/jdks/'
-                sh 'cp -r /home/gradle/.gradle_cache/wrapper/ /home/gradle/.gradle/wrapper/'
-                sh 'cp -r /home/gradle/.gradle_cache/caches/ /home/gradle/.gradle/caches/'
-            }
-        }
-        */
-        stage('setup') {
-            steps {
-                withGradle {
-                    sh './gradlew ${GRADLE_ARGS} --refresh-dependencies --continue setup'
-                }
-                script {
-                    env.MYVERSION = sh(returnStdout: true, script: './gradlew :forge:properties -q | grep "^version:" | cut -d" " -f2').trim()
-                    env.FMLONLY_VERSION = sh(returnStdout: true, script: './gradlew :fmlonly:properties -q | grep "^version:" | cut -d" " -f2').trim()
-                }
-            }
-        }
-        stage('changelog') {
-            when {
-                not {
-                    changeRequest()
-                }
-            }
-            steps {
-                writeChangelog(currentBuild, 'build/changelog.txt')
-            }
-        }
-        stage('publish') {
-            when {
-                not {
-                    changeRequest()
-                }
-            }
-            environment {
-                CROWDIN = credentials('forge-crowdin')
-                KEYSTORE = credentials('forge-jenkins-keystore-old')
-                KEYSTORE_KEYPASS = credentials('forge-jenkins-keystore-old-keypass')
-                KEYSTORE_STOREPASS = credentials('forge-jenkins-keystore-old-keypass')
-            }
-            steps {
-                withCredentials([usernamePassword(credentialsId: 'maven-forge-user', usernameVariable: 'MAVEN_USER', passwordVariable: 'MAVEN_PASSWORD')]) {
-                    withGradle {
-                        sh './gradlew ${GRADLE_ARGS} publish -PkeystoreKeyPass=${KEYSTORE_KEYPASS} -PkeystoreStorePass=${KEYSTORE_STOREPASS} -Pkeystore=${KEYSTORE} -PcrowdinKey=${CROWDIN}'
-                    }
-                }
-            }
-            post {
-                success {
-                    build job: 'filegenerator', parameters: [string(name: 'COMMAND', value: "promote net.minecraftforge:forge ${env.MYVERSION} latest")], propagate: false, wait: false
-                    build job: 'filegenerator', parameters: [string(name: 'COMMAND', value: "promote net.minecraftforge:fmlonly ${env.FMLONLY_VERSION} latest")], propagate: false, wait: false
-                }
-            }
-        }
-        stage('test_publish_pr') { //Publish to local repo to test full process, but don't include credentials so it can't sign/publish to maven
-            when {
-                changeRequest()
-            }
-            environment {
-                CROWDIN = credentials('forge-crowdin')
-            }
-            steps {
-                withGradle {
-                    sh './gradlew ${GRADLE_ARGS} publish -PcrowdinKey=${CROWDIN}'
-                }
-            }
-        }
-    }
-    post {
-        always {
-            script {
-                archiveArtifacts artifacts: 'projects/forge/build/libs/**/*.*', fingerprint: true, onlyIfSuccessful: true, allowEmptyArchive: true
-
-                if (env.CHANGE_ID == null) { // This is unset for non-PRs
-                    discordSend(
-                        title: "${DISCORD_PREFIX} Finished ${currentBuild.currentResult}",
-                        description: '```\n' + getChanges(currentBuild) + '\n```',
-                        successful: currentBuild.resultIsBetterOrEqualTo("SUCCESS"),
-                        result: currentBuild.currentResult,
-                        thumbnail: JENKINS_HEAD,
-                        webhookURL: DISCORD_WEBHOOK
-                    )
-                }
-            }
-        }
-    }
-}

LICENSE-header.txt

@@ -1,16 +1,2 @@
-Minecraft Forge
-Copyright (c) 2016-${year}.
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Lesser General Public
-License as published by the Free Software Foundation version 2.1
-of the License.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-Lesser General Public License for more details.
-
-You should have received a copy of the GNU Lesser General Public
-License along with this library; if not, write to the Free Software
-Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+Copyright (c) Forge Development LLC and contributors
+SPDX-License-Identifier: LGPL-2.1-only

LICENSE.txt

@@ -57,6 +57,9 @@ This software contains a partial repackaging of javaxdelta, a BSD licensed progr
 binary differences and applying them, sourced from the subversion at http://sourceforge.net/projects/javaxdelta/
 authored by genman, heikok, pivot.
 The only changes are to replace some Trove collection types with standard Java collections, and repackaged.
+
+This software includes the Monocraft font from https://github.com/IdreesInc/Monocraft/ for use in the early loading
+display.
 =========================================================================
 
 

buildSrc/build.gradle

@@ -1,9 +1,14 @@
 repositories {
     maven { url = 'https://maven.minecraftforge.net/' }
-	mavenCentral()
+    mavenCentral()
 }
+
 dependencies {
-	implementation 'org.ow2.asm:asm:9.1'
-	implementation 'org.ow2.asm:asm-tree:9.1'
-    implementation 'net.minecraftforge:srgutils:0.4.+'
-}
+    implementation 'org.ow2.asm:asm:9.9.1'
+    implementation 'org.ow2.asm:asm-tree:9.9.1'
+    implementation 'net.minecraftforge:srgutils:0.6.2'
+    implementation 'net.minecraftforge:JarJarMetadata:0.3.27'
+    implementation 'commons-io:commons-io:2.13.0'
+    implementation 'com.google.code.gson:gson:2.10.1'
+    implementation 'org.eclipse.jgit:org.eclipse.jgit:6.7.0.202309050840-r'
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/BundleList.groovy

@@ -0,0 +1,67 @@
+package net.minecraftforge.forge.tasks
+
+import org.gradle.api.tasks.*
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
+
+import java.util.zip.ZipFile
+
+abstract class BundleList extends DefaultTask {
+    @InputFiles abstract ConfigurableFileCollection getConfig()
+    @InputFile abstract RegularFileProperty getServerBundle()
+    @OutputFile abstract RegularFileProperty getOutput()
+
+    BundleList() {
+        config.setFrom(project.configurations.installer)
+        output.convention(project.layout.buildDirectory.file("$name/output.list"))
+        configure {
+            dependsOn(project.tasks.universalJar)
+            inputs.file(project.tasks.universalJar.archiveFile)
+            dependsOn(project.tasks.applyServerBinPatches)
+            inputs.file(project.tasks.applyServerBinPatches.output)
+        }
+    }
+    
+    @TaskAction
+    void run() {
+        def entries = [:] as TreeMap
+        def resolved = project.configurations.installer.resolvedConfiguration.resolvedArtifacts
+        for (def dep : resolved) {
+            def info = Util.getMavenInfoFromDep(dep)
+            //println("$dep.file.sha1\t$info.name\t$info.path")
+            entries.put("$info.art.group:$info.art.name", "$dep.file.sha256\t$info.name\t$info.path")
+        }
+
+        var packed = (AbstractArchiveTask) project.tasks.universalJar
+        var info = Util.getMavenInfoFromTask(packed)
+        def file = packed.archiveFile.get().asFile
+        entries.put("$info.art.group:$info.art.name:$info.art.classifier", "$file.sha256\t$info.name\t$info.path")
+
+        var classifier = 'server'
+        var genned = project.tasks.applyServerBinPatches
+        info = Util.getMavenInfoFromTask(genned, classifier)
+        file = genned.output.get().asFile
+        entries.put("$info.art.group:$info.art.name:$info.art.classifier", "$file.sha256\t$info.name\t$info.path")
+        
+        try (def zip = new ZipFile(serverBundle.get().asFile)) {
+            def entry = zip.getEntry('META-INF/libraries.list')
+            def data = zip.getInputStream(entry).text.split('\n')
+            for (def line : data) {
+                def (sha, artifact, path) = line.split('\t')
+                def (group, name, other) = artifact.split(':', 3)
+                //println("Group: $group Name: $name")
+                def key = "$group:$name"
+                if (other.indexOf(':') != -1){
+                    key += ':' + other.split(':', 2)[1]
+                    //println("\tKey: $key")
+                }
+                if (!entries.containsKey(key))
+                    entries.put(key, line)
+            }
+        }
+        
+        output.get().asFile.text = entries.values().join('\n')
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/BytecodeFinder.groovy

@@ -1,23 +1,22 @@
 package net.minecraftforge.forge.tasks
 
 import groovy.json.JsonBuilder
+import groovy.transform.CompileStatic
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.tasks.InputFile
-import org.gradle.api.tasks.OutputFile
+import org.gradle.api.tasks.Internal
 import org.gradle.api.tasks.TaskAction
-import org.objectweb.asm.ClassReader
-import org.objectweb.asm.Opcodes
 import org.objectweb.asm.tree.ClassNode
 import org.objectweb.asm.tree.FieldNode
 import org.objectweb.asm.tree.MethodNode
 
-import java.util.zip.ZipEntry
-import java.util.zip.ZipInputStream
-
+@CompileStatic
 abstract class BytecodeFinder extends DefaultTask {
     @InputFile abstract RegularFileProperty getJar()
-    @OutputFile abstract RegularFileProperty getOutput()
+    // It should be fine to mark the output as internal as we want to control when we run it anyways.
+    // This also shuts Gradle 8 up about implicit task dependencies.
+    @Internal abstract RegularFileProperty getOutput()
 
     BytecodeFinder() {
         output.convention(project.layout.buildDirectory.dir(name).map { it.file("output.json") })
@@ -27,24 +26,13 @@ abstract class BytecodeFinder extends DefaultTask {
     protected void exec() {
         Util.init()
 
-        def outputFile = output.get().asFile
+        var outputFile = output.get().asFile
         if (outputFile.exists())
             outputFile.delete()
 
         pre()
 
-        jar.get().asFile.withInputStream { i ->
-            new ZipInputStream(i).withCloseable { zin ->
-                ZipEntry zein
-                while ((zein = zin.nextEntry) != null) {
-                    if (zein.name.endsWith('.class')) {
-                        def node = new ClassNode(Opcodes.ASM9)
-                        new ClassReader(zin).accept(node, 0)
-                        process(node)
-                    }
-                }
-            }
-        }
+        Util.processClassNodes(jar.get().asFile, this.&process)
 
         post()
         outputFile.text = new JsonBuilder(getData()).toPrettyString()
@@ -52,8 +40,8 @@ abstract class BytecodeFinder extends DefaultTask {
 
 
     protected process(ClassNode node) {
-        if (node.fields != null) node.fields.each { process(node, it) }
-        if (node.methods != null) node.methods.each { process(node, it) }
+        if (node.fields !== null) node.fields.each { process(node, it) }
+        if (node.methods !== null) node.methods.each { process(node, it) }
     }
 
     protected pre() {}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/BytecodePredicateFinder.groovy

@@ -0,0 +1,48 @@
+package net.minecraftforge.forge.tasks
+
+import groovy.transform.CompileStatic
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Internal
+import org.objectweb.asm.Opcodes
+import org.objectweb.asm.tree.ClassNode
+import org.objectweb.asm.tree.MethodNode
+
+@CompileStatic
+abstract class BytecodePredicateFinder extends BytecodeFinder {
+
+    @Internal
+    abstract Property<Closure<Boolean>> getPredicate()
+
+    private final Map<String, List<String>> matches = new TreeMap<>(Comparator.naturalOrder())
+
+    @Override
+    protected process(ClassNode parent, MethodNode node) {
+        for (final current : node.instructions) {
+            if (predicate.get().call(parent, node, current)) {
+                var methods = matches.compute(parent.name, { k, v -> v ?: new ArrayList<>() })
+
+                // only add non-synthetic methods
+                if ((node.access & Opcodes.ACC_SYNTHETIC) == 0) {
+                    methods.add(node.name + node.desc)
+                }
+
+                return
+            }
+        }
+    }
+
+    @Internal
+    @Override
+    protected Object getData() {
+        var array = new ArrayList<Object>()
+        matches.forEach { c, m ->
+            {
+                array.add(
+                        'class': c,
+                        'methods': m
+                )
+            }
+        }
+        return array ?: { throw new RuntimeException('Failed to find any targets, please ensure that method names and descriptors are correct.') }()
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/CheckATs.groovy

@@ -1,267 +0,0 @@
-package net.minecraftforge.forge.tasks
-
-import net.minecraftforge.srgutils.IMappingFile
-import org.gradle.api.file.ConfigurableFileCollection
-import org.gradle.api.file.RegularFileProperty
-
-import org.gradle.api.DefaultTask
-import org.gradle.api.tasks.InputFile
-import org.gradle.api.tasks.InputFiles
-import org.gradle.api.tasks.Optional
-import org.gradle.api.tasks.TaskAction
-import org.objectweb.asm.Opcodes
-
-abstract class CheckATs extends DefaultTask {
-	@InputFile abstract RegularFileProperty getInheritance()
-	@InputFiles abstract ConfigurableFileCollection getAts()
-    @InputFile @Optional abstract RegularFileProperty getMappings()
-	
-    @TaskAction
-    protected void exec() {
-        def mappings = mappings.map { IMappingFile.load(it.asFile) }.getOrNull()
-		Util.init()
-		def parse = { line ->
-			def idx = line.indexOf('#')
-			def comment = idx == -1 ? null : line.substring(idx)
-			if (idx != -1) line = line.substring(0, idx - 1)
-			def (modifier, cls, desc) = (line.trim() + '     ').split(' ', -1)
-			def key = cls + (desc.isEmpty() ? '' : ' ' + desc)
-			return [modifier, cls, desc, comment, key]
-		}
-		def accessLevel = { access ->
-			if ((access & Opcodes.ACC_PUBLIC)    != 0) return 3
-			if ((access & Opcodes.ACC_PROTECTED) != 0) return 2
-			if ((access & Opcodes.ACC_PRIVATE)   != 0) return 0
-			return 1
-		}
-		def accessStr = { access ->
-			if (access.endsWith('-f') || access.endsWith('+f'))
-				return 4
-			switch (access.toLowerCase()) {
-				case 'public':    return 3
-				case 'protected': return 2
-				case 'default':   return 1
-				case 'private':   return 0
-				default:          return -1
-			}
-		}
-		def json = inheritance.get().asFile.json()
-		
-		ats.each { f -> 
-			TreeMap lines = [:]
-			def group = null
-			for (def line : f.readLines()) {
-				if (line.isEmpty()) continue
-				if (line.startsWith('#group ')) {
-					def (modifier, cls, desc, comment, key) = parse.call(line.substring(7))
-					
-					if (desc != '*' && desc != '*()' && desc != '<init>')
-						throw new IllegalStateException('Invalid group: ' + line)
-					
-					group = [modifier: modifier, cls: cls, desc: desc, comment: comment, 
-						existing: [] as Set,
-						children: [] as TreeSet,
-						group: true
-					]
-					if (lines.containsKey(key))
-						throw new IllegalStateException('Duplicate group: ' + line)
-					
-					lines[key] = group
-				} else if (group != null) {
-					if (line.startsWith('#endgroup')) {
-						group = null
-					} else {
-						def (modifier, cls, desc, comment, key) = parse.call(line)
-						group['existing'].add(key)
-					}
-				} else if (line.startsWith('#endgroup')) {
-					throw new IllegalStateException('Invalid group ending: ' + line)
-				} else if (line.startsWith('#')) {
-					//Nom
-				} else {
-					def (modifier, cls, desc, comment, key) = parse.call(line)
-					if (lines.containsKey(key)) {
-						println('Duplicate: ' + line)
-						continue
-					}
-					lines[key] = [modifier: modifier, cls: cls, desc: desc, comment: comment, group: false]
-				}
-			}
-			
-			// Process Groups, this will remove any entries outside the group that is covered by the group
-			for (def key : new ArrayList<>(lines.keySet())) {
-				def entry = lines.get(key)
-				if (entry != null && entry['group']) {
-					def cls = entry['cls']
-					def jcls = json.get(cls.replaceAll('\\.', '/'))
-					if (jcls == null) {
-						lines.remove(key)
-						println('Invalid Group: ' + key)
-					} else if ('*' == entry['desc']) {
-						if (!jcls.containsKey('fields')) {
-							lines.remove(key)
-							println('Invalid Group, Class has no fields: ' + key)
-						} else {
-							jcls['fields'].each { field, value ->
-								def fkey = cls + ' ' + field
-								if (accessLevel.call(value['access']) < accessStr.call(entry['modifier'])) {
-									if (lines.containsKey(fkey)) {
-										lines.remove(fkey)
-									} else if (!entry['existing'].contains(fkey)) {
-										println('Added: ' + fkey)
-									}
-									entry['children'].add(fkey)
-								} else if (lines.containsKey(fkey)) {
-									lines.remove(fkey)
-									println('Removed: ' + fkey)
-								}
-							}
-							entry['existing'].stream().findAll{ !entry['children'].contains(it) }.each{ println('Removed: ' + it) }
-						}
-					} else if ('*()' == entry['desc']) {
-						if (!jcls.containsKey('methods')) {
-							lines.remove(key)
-							println('Invalid Group, Class has no methods: ' + key)
-						} else {
-							jcls['methods'].each{ mtd, value ->
-								if (mtd.startsWith('<clinit>') || mtd.startsWith('lambda$'))
-									return
-								key = cls + ' ' + mtd.replace(' ', '')
-								if (accessLevel.call(value['access']) < accessStr.call(entry['modifier'])) {
-									if (lines.containsKey(key)) {
-										lines.remove(key)
-									} else if (!entry['existing'].contains(key)) {
-										println('Added: ' + key)
-									}
-									entry['children'].add(key)
-								} else if (lines.containsKey(key)) {
-									lines.remove(key)
-									println('Removed: ' + key)
-								}
-							}
-							entry['existing'].stream().findAll{ !entry['children'].contains(it) }.each{ println('Removed: ' + it) }
-						}
-					} else if ('<init>' == entry['desc']) { //Make all public non-abstract subclasses
-						json.each{ tcls,value -> 
-							if (!value.containsKey('methods') || ((value['access'] & Opcodes.ACC_ABSTRACT) != 0))
-								return
-							def parents = [] as Set
-							def parent = tcls
-							while (parent != null && json.containsKey(parent)) {
-								parents.add(parent)
-								def p = json[parent]
-								parent = p == null ? null : p['superName']
-							}
-							if (parents.contains(cls.replaceAll('\\.', '/'))) {
-								value['methods'].each{ mtd, v -> 
-									if (mtd.startsWith('<init>')) {
-										def child = tcls.replaceAll('/', '\\.') + ' ' + mtd.replace(' ', '')
-										if (accessLevel.call(v['access']) < 3) {
-											if (lines.containsKey(child)) {
-												lines.remove(child)
-											} else if (!entry['existing'].contains(child)) {
-												println('Added: ' + child)
-											}
-											entry['children'].add(child)
-										} else if (lines.containsKey(child)) {
-											lines.remove(child)
-											println('Removed: ' + child)
-										}
-									}
-								}
-							}
-						}
-						entry['existing'].stream().findAll{ !entry['children'].contains(it) }.each{ println('Removed: ' + it) }
-					}
-				}
-			}
-			
-			// Process normal lines, remove invalid and remove narrowing
-			for (def key : new ArrayList<>(lines.keySet())) {
-				def entry = lines.get(key)
-				if (entry != null && !entry['group']) {
-					def cls = entry['cls']
-					def jcls = json.get(cls.replaceAll('\\.', '/'))
-					if (jcls == null) {
-						lines.remove(key)
-						println('Invalid: ' + key)
-					} else if (entry['desc'] == '') {
-						if (accessLevel.call(jcls['access']) > accessStr.call(entry['modifier']) && (entry.comment == null || !entry.comment.startsWith('#force '))) {
-							lines.remove(key)
-							println('Invalid Narrowing: ' + key)
-						}
-					} else if (!entry['desc'].contains('(')) {
-						if (!jcls.containsKey('fields') || !jcls['fields'].containsKey(entry['desc'])) {
-							lines.remove(key)
-							println('Invalid: ' + key)
-						} else {
-							def value = jcls['fields'][entry['desc']]
-							if (accessLevel.call(value['access']) > accessStr.call(entry['modifier']) && (entry.comment == null || !entry.comment.startsWith('#force '))) {
-								lines.remove(key)
-								println('Invalid Narrowing: ' + key)
-								println(entry.comment)
-							}
-						}
-					} else {
-						def jdesc = entry['desc'].replace('(', ' (')
-						if (!jcls.containsKey('methods') || !jcls['methods'].containsKey(jdesc)) {
-							lines.remove(key)
-							println('Invalid: ' + key)
-						} else {
-							def value = jcls['methods'][jdesc]
-							if (accessLevel.call(value['access']) > accessStr.call(entry['modifier']) && (entry.comment == null || !entry.comment.startsWith('#force '))) {
-								lines.remove(key)
-								println('Invalid Narrowing: ' + key)
-							}
-						}
-					}
-				}
-			}
-
-			
-			def data = []
-            def remapComment = { entry ->
-                if (!mappings || !entry || !entry.desc) return null
-                def comment = entry.comment?.substring(1)?.trim()
-                def jsonCls = json.get(entry.cls.replaceAll('\\.', '/'))
-                def mappingsClass = mappings?.getClass(jsonCls.name)
-                if (!mappingsClass) return entry.comment
-                def idx = entry.desc.indexOf('(')
-                def mappedName = idx == -1
-                        ? mappingsClass.remapField(entry.desc)
-                        : mappingsClass.remapMethod(entry.desc.substring(0, idx), entry.desc.substring(idx))
-                if (!mappedName) return entry.comment
-                if (mappedName == '<init>')
-                    mappedName = 'constructor'
-
-                if (comment?.startsWith(mappedName))
-                    return '# ' + comment
-                if (comment && comment.indexOf(' ') != -1) {
-                    def split = comment.split(" - ").toList()
-                    if (split[0].indexOf(' ') != -1)
-                        // The first string is more than one word, so append before it
-                        return "# ${mappedName} - ${comment}"
-                    split.remove(0)
-                    return "# ${mappedName} - ${String.join(' - ', split)}"
-                }
-                return '# ' + mappedName
-            }
-			lines.each { key,value -> 
-				if (!value.group) {
-                    def comment = remapComment.call(value)
-					data.add(value.modifier + ' ' + key + (comment ? ' ' + comment : ''))
-				} else {
-					data.add('#group ' + value.modifier + ' ' + key + (value.comment == null ? '' : ' ' + value.comment))
-					value.children.each {
-                        def line = value.modifier + ' ' + it
-                        def (modifier, cls, desc, comment) = parse.call(line)
-                        comment = remapComment.call([modifier: modifier, cls: cls, desc: desc, comment: comment])
-                        data.add(line + (comment ? ' ' + comment : ''))
-                    }
-					data.add('#endgroup')
-				}
-			}
-			f.text = data.join('\n')
-		}
-	}
-}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/CheckExcs.groovy

@@ -1,94 +0,0 @@
-package net.minecraftforge.forge.tasks
-
-import org.gradle.api.file.ConfigurableFileCollection
-import org.gradle.api.file.RegularFileProperty
-
-import org.gradle.api.DefaultTask
-import org.gradle.api.tasks.InputFile
-import org.gradle.api.tasks.InputFiles
-import org.gradle.api.tasks.TaskAction
-
-import org.objectweb.asm.ClassReader
-import org.objectweb.asm.ClassVisitor
-import org.objectweb.asm.MethodVisitor
-import org.objectweb.asm.Opcodes
-import org.objectweb.asm.Type
-
-import java.util.zip.ZipEntry
-import java.util.zip.ZipInputStream
-
-abstract class CheckExcs extends DefaultTask {
-	@InputFile abstract RegularFileProperty getBinary()
-	@InputFiles abstract ConfigurableFileCollection getExcs()
-	
-    @TaskAction
-    protected void exec() {
-		Util.init()
-		def known = []
-		binary.get().asFile.withInputStream { i ->
-			new ZipInputStream(i).withCloseable { zin ->
-				def visitor = new ClassVisitor(Opcodes.ASM9) {
-					private String cls
-					@Override
-					public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
-						this.cls = name
-					}
-					
-					@Override
-					public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
-						known.add(this.cls + '.' + name + descriptor)
-						super.visitMethod(access, name, descriptor, signature, exceptions)
-					}
-				}
-				ZipEntry zein
-				while ((zein = zin.nextEntry) != null) {
-					if (zein.name.endsWith('.class')) {
-						ClassReader reader = new ClassReader(zin)
-						reader.accept(visitor, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES)
-					}
-				}
-			}
-		}
-		
-		excs.each { f -> 
-			def lines = []
-			f.eachLine { line ->
-				def idx = line.indexOf('#')
-				if (idx == 0 || line.isEmpty()) {
-					return
-				}
-				
-				def comment = idx == -1 ? null : line.substring(idx)
-				if (idx != -1) line = line.substring(0, idx - 1)
-				
-				if (!line.contains('=')) {
-					println('Invalid: ' + line)
-					return
-				}
-				
-				def (key, value) = line.split('=', 2)
-				if (!known.contains(key)) {
-					println('Unknown: ' + line)
-					return
-				}
-				
-				def (cls, desc) = key.split('\\.', 2)
-				if (!desc.contains('(')) {
-					println('Invalid: ' + line)
-					return
-				}
-				def name = desc.split('\\(', 2)[0]
-				desc = '(' + desc.split('\\(', 2)[1]
-				
-				def (exceptions, args) = value.contains('|') ? value.split('|', 2) : [value, '']
-				
-				if (args.split(',').length != Type.getArgumentTypes(desc).length) {
-					println('Invalid: ' + line)
-					return
-				}
-				lines.add(line)
-			}
-			f.text = lines.sort().join('\n')
-		}
-	}
-}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/CheckPatches.groovy

@@ -1,219 +0,0 @@
-package net.minecraftforge.forge.tasks
-
-import org.gradle.api.DefaultTask
-import org.gradle.api.file.DirectoryProperty
-import org.gradle.api.tasks.Input
-import org.gradle.api.tasks.InputDirectory
-import org.gradle.api.tasks.TaskAction
-
-import java.nio.file.Files
-import java.nio.file.Paths
-import java.util.regex.Pattern
-
-abstract class CheckPatches extends DefaultTask {
-    @InputDirectory abstract DirectoryProperty getPatchDir()
-    @Input boolean autoFix = false
-
-    @TaskAction
-    protected void exec() {
-        def hasS2SArtifact = [
-                Paths.get("patches/minecraft/net/minecraft/client/renderer/ViewArea.java.patch"),
-                Paths.get("patches/minecraft/net/minecraft/data/models/blockstates/Variant.java.patch")
-        ]
-
-        def verified = true;
-        patchDir.get().asFileTree.each { patch ->
-            def patchPath = project.rootDir.toPath().relativize(patch.toPath())
-            verified &= verifyPatch(patch, autoFix, patchPath.toString(), hasS2SArtifact.contains(patchPath))
-        }
-
-        if (!verified)
-            throw new RuntimeException('One or more patches failed verification. Check the log for errors.')
-    }
-
-    def verifyPatch(patch, fix, patchPath, hasS2SArtifact) {
-        def hunk_start_pattern = Pattern.compile('^@@ -[0-9,]* \\+[0-9,_]* @@$')
-        def white_space_pattern = Pattern.compile('^[+\\-]\\s*$')
-        def import_pattern = Pattern.compile('^[+\\-]\\s*import.*')
-        def field_pattern = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final)?([^=;]*)(=.*)?;\\s*$')
-        def method_pattern = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final)?([^(]*)[(]([^)]*)?[)]\\s*[{]\\s*$')
-        def class_pattern = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final[\\s]*)?(class|interface)([^{]*)[{]\\s*$')
-
-        def accessMap = [("private"):0, (null):1, ("protected"):2, ("public"):3]
-
-        def hasProblem = false;
-        def lines = patch.readLines()
-
-        def hunksStart = 0
-        def onlyWhiteSpace = false
-
-        def didFix = false
-        def newLines = []
-        def whiteSpaceErrors = []
-
-        // First two lines are file name ++/-- and we do not care
-        newLines.add(lines[0] + '\n')
-        newLines.add(lines[1] + '\n')
-
-        int i = 2
-        for (; i < lines.size(); ++i) {
-            def line = lines[i]
-            newLines.add(line + '\n')
-
-            if (hunk_start_pattern.matcher(line).find()) {
-                if (onlyWhiteSpace) {
-                    if (fix || hasS2SArtifact) {
-                        logger.lifecycle("Removing white space hunk starting at line {}, file: {}", hunksStart + 1, patchPath)
-                        def toRemove = i - hunksStart;
-                        while (toRemove-- > 0)
-                            newLines.remove(newLines.size() - 1)
-                        didFix = true
-                    }
-                    else {
-                        logger.lifecycle("Patch contains only white space hunk starting at line {}, file: {}", hunksStart + 1, patchPath)
-                        hasProblem = true
-                    }
-                }
-                else {
-                    if (!whiteSpaceErrors.empty)
-                        hasProblem = true
-                    whiteSpaceErrors.each { error -> logger.lifecycle(error) }
-                    whiteSpaceErrors.clear()
-                }
-                hunksStart = i
-                onlyWhiteSpace = true
-                continue
-            }
-
-            if (line.startsWithAny('+','-')) {
-                def prefixChange = false
-                def prevLine = lines[i - 1]
-
-                if (line.charAt(0) == (char)'+' && prevLine.charAt(0) == (char)'-') {
-                    def prevTrim = prevLine.substring(1).replaceAll("\\s", "")
-                    def currTrim = line.substring(1).replaceAll("\\s", "")
-
-                    if (prevTrim.equals(currTrim)) {
-                        prefixChange = true
-                    }
-
-                    def pMatcher = field_pattern.matcher(prevLine)
-                    def cMatcher = field_pattern.matcher(line)
-
-                    if (pMatcher.find() && cMatcher.find() &&
-                            pMatcher.group(6) == cMatcher.group(6) && // = ...
-                            pMatcher.group(5) == cMatcher.group(5) && // field name
-                            pMatcher.group(3) == cMatcher.group(3) && // static
-                            (accessMap[pMatcher.group(2)] < accessMap[cMatcher.group(2)] || pMatcher.group(4) != cMatcher.group(4))) {
-                        logger.lifecycle("Patch contains access changes or final removal at line {}, file: {}", i + 1, patchPath)
-                        hasProblem = true
-                    }
-
-                    pMatcher = method_pattern.matcher(prevLine)
-                    cMatcher = method_pattern.matcher(line)
-
-                    if (pMatcher.find() && cMatcher.find() &&
-                            pMatcher.group(6) == cMatcher.group(6) && // params
-                            pMatcher.group(5) == cMatcher.group(5) && // <T> void name
-                            pMatcher.group(3) == cMatcher.group(3) && // static
-                            (accessMap[pMatcher.group(2)] < accessMap[cMatcher.group(2)] || pMatcher.group(4) != cMatcher.group(4))) {
-                        logger.lifecycle("Patch contains access changes or final removal at line {}, file: {}", i + 1, patchPath)
-                        hasProblem = true
-                    }
-
-                    pMatcher = class_pattern.matcher(prevLine)
-                    cMatcher = class_pattern.matcher(line)
-
-                    if (pMatcher.find() && cMatcher.find() &&
-                            pMatcher.group(6) == cMatcher.group(6) && // ClassName<> extends ...
-                            pMatcher.group(5) == cMatcher.group(5) && // class | interface
-                            pMatcher.group(3) == cMatcher.group(3) && // static
-                            (accessMap[pMatcher.group(2)] < accessMap[cMatcher.group(2)] || pMatcher.group(4) != cMatcher.group(4))) {
-                        logger.lifecycle("Patch contains access changes or final removal at line {}, file: {}", i + 1, patchPath)
-                        hasProblem = true
-                    }
-                }
-
-                if (line.charAt(0) == (char)'-' && i + 1 < lines.size()) {
-                    def nextLine = lines[i + 1]
-                    if (nextLine.charAt(0) == (char)'+') {
-                        def nextTrim = nextLine.substring(1).replaceAll("\\s", "")
-                        def currTrim = line.substring(1).replaceAll("\\s", "")
-
-                        if (nextTrim.equals(currTrim)) {
-                            prefixChange = true
-                        }
-                    }
-                }
-
-                def isWhiteSpaceChange = white_space_pattern.matcher(line).find()
-
-                if (!prefixChange && !isWhiteSpaceChange) {
-                    onlyWhiteSpace = hasS2SArtifact && import_pattern.matcher(line).find()
-                }
-                else if (isWhiteSpaceChange) {
-                    def prevLineChange = prevLine.startsWithAny('+','-')
-                    def nextLineChange = i + 1 < lines.size() && lines[i + 1].startsWithAny('+','-')
-
-                    if (!prevLineChange && !nextLineChange) {
-                        whiteSpaceErrors.add(String.format("Patch contains white space change in valid hunk at line %d (cannot auto fix), file: %s", i + 1, patchPath))
-                    }
-                }
-
-                if (line.contains("\t")) {
-                    if (!fix) {
-                        logger.lifecycle("Patch contains tabs on line {}, file: {}", i + 1, patchPath)
-                        hasProblem = true
-                    }
-                    else {
-                        logger.lifecycle("Fixing tabs on line {}, file: {}", i + 1, patchPath)
-                        line = line.replaceAll('\t', '    ')
-                        newLines.remove(newLines.size() - 1)
-                        newLines.add(line + '\n')
-                        didFix = true
-                    }
-                }
-
-                if (import_pattern.matcher(line).find() && !hasS2SArtifact) {
-                    logger.lifecycle("Patch contains import change on line {}, file: {}", i + 1, patchPath)
-                    hasProblem = true
-                }
-            }
-        }
-
-        if (onlyWhiteSpace) {
-            if (fix || hasS2SArtifact) {
-                logger.lifecycle("Removing white space hunk starting at line {}, file: {}", hunksStart + 1, patchPath)
-                def toRemove = i - hunksStart;
-                while (toRemove-- > 0)
-                    newLines.remove(newLines.size() - 1)
-                didFix = true
-            }
-            else {
-                logger.lifecycle("Patch contains only white space hunk starting at line {}, file: {}", hunksStart + 1, patchPath)
-                hasProblem = true
-            }
-        }
-        else {
-            if (!whiteSpaceErrors.empty)
-                hasProblem = true
-            whiteSpaceErrors.each { error -> logger.lifecycle(error) }
-        }
-
-        if (didFix) {
-            if (newLines.size() <= 2) {
-                logger.lifecycle("Patch is now empty removing, file: {}", patchPath)
-                Files.delete(patch.toPath())
-            }
-            else {
-                if (!hasS2SArtifact)
-                    logger.lifecycle("*** Updating patch file. Please run setup then genPatches again. ***")
-                patch.withWriter('UTF-8') { writer ->
-                    newLines.each { l -> writer.write(l) }
-                }
-            }
-        }
-
-        return !hasProblem
-    }
-}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/CheckSAS.groovy

@@ -1,63 +0,0 @@
-package net.minecraftforge.forge.tasks
-
-import org.gradle.api.file.ConfigurableFileCollection
-import org.gradle.api.file.RegularFileProperty
-
-import org.gradle.api.DefaultTask
-import org.gradle.api.tasks.InputFile
-import org.gradle.api.tasks.InputFiles
-import org.gradle.api.tasks.TaskAction
-
-abstract class CheckSAS extends DefaultTask {
-	@InputFile abstract RegularFileProperty getInheritance()
-	@InputFiles abstract ConfigurableFileCollection getSass()
-	
-    @TaskAction
-    protected void exec() {
-		Util.init()
-		def json = inheritance.get().asFile.json()
-		
-		sass.each { f -> 
-			def lines = []
-			f.eachLine { line ->
-				if (line[0] == '\t') return //Skip any tabbed lines, those are ones we add
-				def idx = line.indexOf('#')
-				if (idx == 0 || line.isEmpty()) {
-					lines.add(line)
-					return
-				}
-				def comment = idx == -1 ? null : line.substring(idx)
-				if (idx != -1) line = line.substring(0, idx - 1)
-				def (cls, desc) = (line.trim() + '    ').split(' ', -1)
-				cls = cls.replaceAll('\\.', '/')
-				desc = desc.replace('(', ' (')
-
-				if (json[cls] == null || (!desc.isEmpty() && (json[cls]['methods'] == null || json[cls]['methods'][desc] == null))) {
-					println('Invalid: ' + line)
-					return
-				}
-
-				//Class SAS
-				if (desc.isEmpty()) {
-					lines.add(cls + (comment == null ? '' : ' ' + comment))
-					if (json[cls]['methods'] != null)
-						(json[cls]['methods'] as TreeMap).each {
-							findChildMethods(json, cls, it.key).each { lines.add('\t' + it) }
-						}
-					return
-				}
-
-				//Method SAS
-				lines.add(cls + ' ' + desc.replace(' ', '') + (comment == null ? '' : ' ' + comment))
-				findChildMethods(json, cls, desc).each { lines.add('\t' + it) }
-			}
-			f.text = lines.join('\n')
-		}
-	}
-
-	protected static findChildMethods(json, cls, desc)
-	{
-		return json.values().findAll{ it.methods != null && it.methods[desc] != null && it.methods[desc].override == cls}
-				.collect { it.name + ' ' + desc.replace(' ', '') } as TreeSet
-	}
-}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/CleanProperties.groovy

@@ -0,0 +1,97 @@
+package net.minecraftforge.forge.tasks;
+
+import groovy.transform.CompileDynamic;
+import groovy.transform.CompileStatic;
+
+import java.util.Properties;
+import java.util.Enumeration;
+import java.util.Map;
+import java.util.TreeSet;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.Reader;
+import java.io.InputStreamReader;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.Writer;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.Set;
+
+/**
+ * Eclipse config files are literally just java properties, with the header cleaned up.
+ * https://github.com/eclipse/buildship/blob/5b2c7fca7fa86cd74d71b3c099c7b1559eba038e/org.eclipse.buildship.core/src/main/java/org/eclipse/buildship/core/internal/configuration/PreferenceStore.java#L238
+ *
+ * This does the same thing, as well as sorting alphabetically.
+ * It also ignores all comments. We can add them latter if someone cares.
+ */
+@CompileStatic
+public class CleanProperties extends Properties {
+    private static final long serialVersionUID = 1L;
+    private static final String LINE_SEP = System.getProperty("line.separator");
+    private static final String UNIX_LINE_SEP = "\n";
+    private static final Charset ENCODING = StandardCharsets.UTF_8;
+
+    public CleanProperties load(File input) throws IOException {
+        if (input.exists()) {
+            try (Reader is = new InputStreamReader(new FileInputStream(input), ENCODING)) {
+                super.load(is);
+            }
+        }
+        return this;
+    }
+
+    public void store(File out) throws IOException {
+        if (!out.getParentFile().exists())
+            out.getParentFile().mkdirs();
+
+        try (OutputStream os = new FileOutputStream(out)) {
+            store(os, null);
+        }
+    }
+
+    @Override
+    public synchronized Enumeration<Object> keys() {
+        Set<Object> ret = new TreeSet<>();
+        for (Enumeration<?> e = super.keys(); e.hasMoreElements();)
+            ret.add(e.nextElement());
+        return Collections.enumeration(ret);
+    }
+
+    @CompileDynamic
+    @Override
+    public Set<Map.Entry<Object, Object>> entrySet() {
+        Set<Map.Entry<Object, Object>> ret = new TreeSet<>((l, r) -> ((String)l.getKey()).compareTo((String)r.getKey()));
+        ret.addAll(super.entrySet());
+        return ret;
+    }
+
+    @Override
+    public void store(OutputStream out, String comments) throws IOException {
+        out.write(clean().getBytes(ENCODING));
+        out.flush();
+    }
+
+    @Override
+    public void store(Writer out, String comments) throws IOException {
+        out.write(clean());
+        out.flush();
+    }
+
+    private String clean() throws IOException {
+        ByteArrayOutputStream tmp = new ByteArrayOutputStream();
+        try {
+            super.store(tmp, null);
+        } finally {
+            tmp.close();
+        }
+
+        String ret = tmp.toString(ENCODING).replace(LINE_SEP, UNIX_LINE_SEP);
+        ret = ret.substring(ret.indexOf(UNIX_LINE_SEP) + 1);
+        return ret;
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/ClosureHelper.groovy

@@ -1,5 +1,7 @@
 package net.minecraftforge.forge.tasks
 
+import groovy.transform.stc.FirstParam
+
 import java.util.function.BiConsumer
 
 public class ClosureHelper {
@@ -22,7 +24,7 @@ public class ClosureHelper {
         }
     }
     
-    static <T> T apply(T obj, Closure cl) {
+    static <T> T apply(T obj, @DelegatesTo(value = FirstParam, strategy = Closure.DELEGATE_FIRST) Closure cl) {
         cl.delegate = obj
         cl.resolveStrategy = Closure.DELEGATE_FIRST
         cl()

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/Crowdin.groovy

@@ -1,73 +0,0 @@
-package net.minecraftforge.forge.tasks
-
-import org.gradle.api.DefaultTask
-import org.gradle.api.file.RegularFileProperty
-import org.gradle.api.provider.Property
-import org.gradle.api.tasks.Input
-import org.gradle.api.tasks.Optional
-import org.gradle.api.tasks.OutputFile
-import org.gradle.api.tasks.TaskAction
-
-import java.util.zip.ZipEntry
-import java.util.zip.ZipInputStream
-import java.util.zip.ZipOutputStream
-
-abstract class Crowdin extends DefaultTask {
-    @Input abstract Property<String> getId()
-	@Input @Optional abstract Property<String> getKey()
-	@Input boolean json = true
-	@OutputFile abstract RegularFileProperty getOutput()
-	@OutputFile abstract RegularFileProperty getExport()
-
-    Crowdin() {
-		outputs.upToDateWhen{ false }
-		id.convention('minecraft-forge')
-		output.convention(project.layout.buildDirectory.dir(name).map {it.file("output.zip") })
-		export.convention(project.layout.buildDirectory.dir(name).map {it.file("export.json") })
-	}
-
-    @TaskAction
-    def run() {
-		File outputFile = output.get().asFile
-		File exportFile = export.get().asFile
-		if (outputFile.exists())
-			outputFile.delete()
-		
-		if (!key.isPresent())
-			return
-		String key = this.key.get()
-		String id = this.id.get()
-		
-		// Force an export
-		new URL("https://api.crowdin.com/api/project/${id}/export?key=${key}").withInputStream { i ->
-			exportFile.withOutputStream { it << i }
-		}
-		
-		if (!exportFile.text.contains('success')) {
-			throw new RuntimeException("Crowdin export failed, see ${exportFile} for more info")
-		}
-
-		new URL("https://api.crowdin.com/api/project/${id}/download/all.zip?key=${key}").withInputStream { i -> 
-			new ZipInputStream(i).withCloseable { zin ->
-				outputFile.withOutputStream { out ->
-					new ZipOutputStream(out).withCloseable { zout -> 
-						ZipEntry zein
-						while ((zein = zin.nextEntry) != null) {
-							if (zein.isDirectory()) {
-								zout.putNextEntry(new ZipEntry(zein.name))
-							} else {
-								// 1.13+ uses json
-								if (zein.name.endsWith('.json') == json) {
-									ZipEntry zeout = new ZipEntry(json ? zein.name.toLowerCase() : zein.name)
-									zeout.time = 1
-									zout.putNextEntry(zeout)
-									zout << zin
-								}
-							}
-						}
-					}
-				}
-			}
-		}
-    }
-}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/DownloadLibraries.groovy

@@ -27,7 +27,7 @@ abstract class DownloadLibraries extends DefaultTask {
     def run() {
 		Util.init()
 		File outputDir = output.get().asFile
-        def libraries = new ArrayList()
+        var libraries = new ArrayList<String>()
 
 		def json = input.get().asFile.json().libraries.each { lib ->
 		    //TODO: Thread?
@@ -35,7 +35,7 @@ abstract class DownloadLibraries extends DefaultTask {
 			artifacts.each{ art -> 
 				def target = new File(outputDir, art.path)
 				libraries.add(target.absolutePath)
-				if (!target.exists() || !art.sha1.equals(target.sha1())) {
+				if (!target.exists() || art.sha1 != target.sha1()) {
 					project.logger.lifecycle("Downloading ${art.url}")
 					if (!target.parentFile.exists()) {
 						target.parentFile.mkdirs()
@@ -43,7 +43,7 @@ abstract class DownloadLibraries extends DefaultTask {
 					new URL(art.url).withInputStream { i ->
 						target.withOutputStream { it << i }
 					}
-					if (!art.sha1.equals(target.sha1())) {
+					if (art.sha1 != target.sha1()) {
 						throw new IllegalStateException("Failed to download ${art.url} to ${target.canonicalPath} SHA Mismatch")
 					}
 				}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/ExtractFile.groovy

@@ -0,0 +1,28 @@
+package net.minecraftforge.forge.tasks
+
+import groovy.transform.CompileStatic
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.*
+
+import java.util.zip.ZipFile
+
+@CompileStatic
+abstract class ExtractFile extends DefaultTask {
+    @InputFile abstract RegularFileProperty getInput()
+    @Input abstract Property<String> getTarget()
+    @OutputFile abstract RegularFileProperty getOutput()
+
+    @TaskAction
+    protected void exec() {
+        var zip = new ZipFile(input.get().asFile);
+        var entry = zip.getEntry(target.get())
+        if (entry == null)
+            throw new IllegalStateException(input.get().asFile.absolutePath + " does not contain " + target.get())
+        var stream = zip.getInputStream(entry)
+        output.get().asFile.withOutputStream { out ->
+            stream.transferTo(out)
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/FieldCompareFinder.groovy

@@ -1,20 +1,11 @@
 package net.minecraftforge.forge.tasks
 
+import groovy.transform.CompileStatic
 import groovy.transform.EqualsAndHashCode
 
-import java.util.ArrayList
-import java.util.HashMap
-import java.util.TreeMap
-import java.util.TreeSet
-import java.util.function.BiConsumer
-
-import org.gradle.api.DefaultTask
 import org.gradle.api.tasks.*
-
-import org.objectweb.asm.Opcodes
-import org.objectweb.asm.Type
+import org.objectweb.asm.tree.AbstractInsnNode
 import org.objectweb.asm.tree.ClassNode
-import org.objectweb.asm.tree.FieldNode
 import org.objectweb.asm.tree.MethodNode
 
 import static org.objectweb.asm.Opcodes.*
@@ -34,17 +25,17 @@ abstract class FieldCompareFinder extends BytecodeFinder {
     
     @Override
     protected process(ClassNode parent, MethodNode node) {
-        def last = null
+        AbstractInsnNode last = null
         def parentInstance = new ObjectTarget(owner: parent.name, name: '', desc: '')
         for (int x = 0; x < node.instructions.size(); x++) {
             def current = node.instructions.get(x)
-            if (current.opcode == IF_ACMPEQ || current.opcode == IF_ACMPNE) {
-                if (last != null && (last.opcode == GETSTATIC || last.opcode == GETFIELD)) {
+            if (current.opcode === IF_ACMPEQ || current.opcode === IF_ACMPNE) {
+                if (last !== null && (last.opcode === GETSTATIC || last.opcode === GETFIELD)) {
                     def target = new Search(cls: last.owner, name: last.name)
                     def wanted = fieldsReverse.get(target)
                     def original = fields.get(wanted)
                     def instance = new ObjectTarget(owner: parent.name, name: node.name, desc: node.desc)
-                    if (wanted != null && (original.blacklist == null || (!original.blacklist.contains(instance) && !original.blacklist.contains(parentInstance)))) {
+                    if (wanted !== null && (original.blacklist === null || (!original.blacklist.contains(instance) && !original.blacklist.contains(parentInstance)))) {
                         targets.computeIfAbsent(wanted, { k -> new TreeSet() }).add(instance)
                     }
                 }
@@ -68,9 +59,10 @@ abstract class FieldCompareFinder extends BytecodeFinder {
 		}
         return ret
     }
-    
+
+    @CompileStatic
     @EqualsAndHashCode(excludes = ['replacement', 'blacklist'])
-    public static class Search {
+    static class Search {
         @Input
         String cls
         
@@ -89,17 +81,17 @@ abstract class FieldCompareFinder extends BytecodeFinder {
             return cls + '.' + name
         }
         
-        def blacklist(def owner, def name, def desc) {
-            if (blacklist == null)
-                blacklist = new HashSet()
+        def blacklist(String owner, String name, String desc) {
+            if (blacklist === null)
+                blacklist = new HashSet<>()
             blacklist.add(new ObjectTarget(owner: owner, name: name, desc: desc))
         }
-        def blacklist(def owner) {
+        def blacklist(String owner) {
             blacklist(owner, '', '')
         }
     }
     
-    def fields(Closure cl) {
+    void fields(Closure cl) {
         new ClosureHelper(cl, {name, ccl ->
             def search = ClosureHelper.apply(new Search(), ccl)
             this.fields.put(name, search)

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/InheritanceData.groovy

@@ -0,0 +1,49 @@
+package net.minecraftforge.forge.tasks
+
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
+import groovy.transform.CompileStatic
+import groovy.transform.TupleConstructor
+
+@CompileStatic
+@TupleConstructor
+final class InheritanceData implements Annotatable {
+    String name
+    int access
+    String superName
+    List<String> interfaces = []
+    Map<String, Method> methods = [:]
+    Map<String, Field> fields = [:]
+    List<Annotation> annotations = []
+
+    @TupleConstructor
+    static final class Method implements Annotatable {
+        int access
+        String override
+        List<Annotation> annotations = []
+    }
+
+    @TupleConstructor
+    static final class Field implements Annotatable {
+        int access
+        String desc
+        List<Annotation> annotations = []
+    }
+
+    @TupleConstructor
+    static final class Annotation {
+        String desc
+    }
+
+    private static final Gson GSON = new Gson()
+    static Map<String, InheritanceData> parse(File file) {
+        try (final reader = file.newReader()) {
+            return GSON.fromJson(reader, new TypeToken<Map<String, InheritanceData>>() {})
+        }
+    }
+}
+
+@CompileStatic
+interface Annotatable {
+    List<InheritanceData.Annotation> getAnnotations()
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/InstallerJar.groovy

@@ -1,44 +1,158 @@
 package net.minecraftforge.forge.tasks
 
+import org.gradle.api.file.DuplicatesStrategy
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
 import org.gradle.api.tasks.bundling.Zip
 import org.gradle.api.tasks.*
-import org.gradle.api.provider.SetProperty
+import org.gradle.api.DefaultTask
+import org.gradle.api.provider.Property
+import groovy.json.JsonSlurper
 
 abstract class InstallerJar extends Zip {
-    @Input @Optional abstract SetProperty<String> getPackedDependencies()
-    
+    @Input @Optional abstract Property<Boolean> getFat()
+    @Input @Optional abstract Property<Boolean> getOffline()
+
     InstallerJar() {
         archiveClassifier.set('installer')
         archiveExtension.set('jar') // Needs to be Zip task to not override Manifest, so set extension
         destinationDirectory.set(project.layout.buildDirectory.dir('libs'))
+        fat.convention(false)
+        offline.convention(false)
 
         def installerJson = project.tasks.installerJson
         def launcherJson = project.tasks.launcherJson
         def downloadInstaller = project.tasks.downloadInstaller
-        
-        dependsOn(installerJson, launcherJson, downloadInstaller)
+
+        dependsOn(installerJson, launcherJson, downloadInstaller, project.configurations.installer)
         from(installerJson, launcherJson)
 
         from(project.rootProject.file('/src/main/resources/url.png'))
         project.afterEvaluate {
             from(project.zipTree(downloadInstaller.output)) {
-                duplicatesStrategy = 'exclude'
+                duplicatesStrategy = DuplicatesStrategy.EXCLUDE
             }
             
-            if (!System.env.MAVEN_USER) {
-                dependsOn(project.universalJar)
-                from(project.universalJar) {
-                    into '/maven/' + project.group.replace('.', '/') + '/' + project.universalJar.archiveBaseName.get() + '/' + project.version + '/'
+            if (fat.get() || offline.get()) {
+                def cfg = project.tasks.register(name + "Config", Configure)
+                cfg.get().configure {
+                    parent = this
+                    dependsOn(project.tasks.installerJson, project.tasks.launcherJson)
                 }
-    
-                packedDependencies.get().forEach {
-                    def jarTask = project.rootProject.getTasks().findByPath(it)
-                    dependsOn(jarTask)
-                    from(jarTask) {
-                        into '/maven/' + jarTask.project.group.replace('.', '/') + '/' + jarTask.archiveBaseName.get() + '/' + jarTask.project.version + '/'
+                dependsOn(cfg)
+            } else {
+                // Things we ALWAYS bundle, this just the server shim jar, because the installer spec only says to extract the file. 
+                // I should make it allow downloads but thats a spec break, and this is just a ~14KB jar
+                [
+                    project.tasks.serverShimJar // Server bootstrap executable jar
+                ].forEach { AbstractArchiveTask packed ->
+                    def path = Util.getMavenInfoFromTask(packed).path
+                    from(packed) {
+                        rename { "maven/$path" }
                     }
                 }
             }
         }
     }
+    
+    static abstract class Configure extends DefaultTask {
+        public Zip parent
+        private int count = 0;
+        
+        @TaskAction
+        protected void exec() {
+            def deps = [:] as java.util.TreeMap
+            
+            // Gather all things that need downloading
+            [
+                project.tasks.installerJson, 
+                project.tasks.launcherJson
+            ].each { task ->
+                def json = task.output.get().asFile.json
+                json.libraries.each { lib -> 
+                    if (lib.downloads?.artifact?.url !== null && !lib.downloads.artifact.url.isEmpty())
+                        deps.put(lib.name, lib.downloads.artifact)
+                }
+            }
+            
+            // First find things we build in this project.
+            [
+                project.tasks.universalJar, // Forge runtime code
+                project.tasks.serverShimJar // Shim jar for dedicated server
+            ].forEach { AbstractArchiveTask packed ->
+                def name = Util.getMavenInfoFromTask(packed).name
+                def info = deps.remove(name)
+                if (info !== null) {
+                    println("Adding: $packed.path $name")
+                    parent.from(packed) {
+                        rename { "maven/$info.path" }
+                    }
+                }
+            }
+            
+            // Find any artifacts from the 'installer' config
+            // This config specifies the runtime files we intend for the interaller to have.
+            // And are typically what we would be developing and testing alongside Forge. 
+            // So we may have local modified versions
+            def cfg = project.configurations.installer
+            while (cfg != null) {
+                //println('')
+                def resolved = cfg.resolvedConfiguration.resolvedArtifacts
+                int found = 0
+                for (def dep : resolved) {
+                    def name = Util.getMavenInfoFromDep(dep).name
+                    def info = deps.remove(name)
+                    if (info == null) {
+                        //println("Skipping: $name")
+                        continue
+                    }
+                    //println("-$name")
+                    found++
+                    addFile(dep.file, info)
+                }
+                
+                if (deps.isEmpty()) {
+                    cfg = null
+                    continue
+                }
+                
+                // Prevent infinite loops if something fucky happens
+                if (found == 0)
+                    throw new IllegalStateException("Failed to find any installer dependencies") 
+                
+                def seen = [] as Set
+                cfg = project.configurations.detachedConfiguration()
+                cfg.transitive = false
+                for (def key : deps.keySet()) {
+                    def (group, artifact, other) = key.split(':', 3)
+                    // Only resolve unique group:artifact so we don't get version overrides
+                    if (seen.add(group + ':' + artifact)) {
+                        //println("+$key")
+                        cfg.dependencies.add(project.dependencies.create(key))
+                    }
+                }
+            }
+        }
+        
+        void addFile(file, info) {
+            boolean pack = parent.offline.get() || info.url.isEmpty()
+            
+            // If it's a offline jar just always pack
+            if (!pack) {
+                try {
+                    var remote = new URL("${info.url}.sha1").getText('UTF-8')
+                    pack = info.sha1 != remote
+                } catch (FileNotFoundException e) {
+                    pack = !info.url.startsWith('https://libraries.minecraft.net/')
+                    // Oh noes its not there!
+                }
+            }
+            
+            if (pack) {
+                println("Adding: $file.absolutePath")
+                parent.from(file) {
+                    rename { "maven/$info.path" }
+                }
+            }
+        }
+    }
 }

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/InstallerJson.groovy

@@ -7,13 +7,13 @@ import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.Property
 import org.gradle.api.provider.SetProperty
 import org.gradle.api.tasks.*
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
 
 import java.nio.file.Files
 
 abstract class InstallerJson extends DefaultTask {
     @OutputFile abstract RegularFileProperty getOutput()
     @InputFiles abstract ConfigurableFileCollection getInput()
-    @Input @Optional abstract SetProperty<String> getPackedDependencies()
     @Input @Optional final Map<String, Object> libraries = new LinkedHashMap<>()
     @Input Map<String, Object> json = new LinkedHashMap<>()
     @InputFile abstract RegularFileProperty getIcon()
@@ -23,29 +23,19 @@ abstract class InstallerJson extends DefaultTask {
     @Input abstract Property<String> getWelcome()
 
     InstallerJson() {
-        getLauncherJsonName().convention('/version.json')
-        getLogo().convention('/big_logo.png')
-        getMirrors().convention('https://files.minecraftforge.net/mirrors-2.0.json')
-        getWelcome().convention("Welcome to the simple ${project.name.capitalize()} installer.")
-                
-        getOutput().convention(project.layout.buildDirectory.file('install_profile.json'))
-
-        ['client', 'server'].each { side ->
-            ['slim', 'extra'].each { type ->
-                def tsk = project.tasks.getByName("download${side.capitalize()}${type.capitalize()}")
-                dependsOn(tsk)
-                input.from(tsk.output)
-            }
-            def tsk = project.tasks.getByName("create${side.capitalize()}SRG")
-            dependsOn(tsk)
-            input.from(tsk.output)
-        }
-
+        launcherJsonName.convention('/version.json')
+        logo.convention('/big_logo.png')
+        mirrors.convention('https://files.minecraftforge.net/mirrors-2.0.json')
+        welcome.convention("Welcome to the ${project.name.capitalize()} installer.")
+        output.convention(project.layout.buildDirectory.file('libs/install_profile.json'))
         
         project.afterEvaluate {
-            (packedDependencies.get().collect{ project.rootProject.tasks.findByPath(it) } + [project.universalJar]).forEach {
-                dependsOn(it)
-                input.from it.archiveFile
+            [
+                project.tasks.universalJar,
+                project.tasks.serverShimJar
+            ].forEach { packed ->
+                dependsOn(packed)
+                input.from packed.archiveFile
             }
         }
     }
@@ -53,17 +43,19 @@ abstract class InstallerJson extends DefaultTask {
     @TaskAction
     protected void exec() {
         def libs = libraries
-        for (def child : packedDependencies.get().collect{ project.rootProject.tasks.findByPath(it) } + [project.universalJar]) {
-            def dep = Util.getMavenDep(child)
-            def path = Util.getMavenPath(child)
-            libs.put(dep.toString(), [
-                name: dep,
+        [
+            project.tasks.universalJar,
+            project.tasks.serverShimJar
+        ].forEach { AbstractArchiveTask packed ->
+            def info = Util.getMavenInfoFromTask(packed)
+            libs.put(info.name, [
+                name: info.name,
                 downloads: [
                     artifact: [
-                        path: path,
-                        url: "https://maven.minecraftforge.net/${path}",
-                        sha1: child.archiveFile.get().asFile.sha1(),
-                        size: child.archiveFile.get().asFile.length()
+                        path: info.path,
+                        url: "https://maven.minecraftforge.net/$info.path",
+                        sha1: packed.archiveFile.get().asFile.sha1(),
+                        size: packed.archiveFile.get().asFile.length()
                     ]
                 ]
             ])

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/JarJarMetadataOptions.java

@@ -0,0 +1,415 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.forge.tasks;
+
+import com.google.common.reflect.TypeToken;
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+import net.minecraftforge.jarjar.metadata.ContainedJarIdentifier;
+import net.minecraftforge.jarjar.metadata.ContainedJarMetadata;
+import net.minecraftforge.jarjar.metadata.ContainedVersion;
+import net.minecraftforge.jarjar.metadata.Metadata;
+import net.minecraftforge.jarjar.metadata.MetadataIOHandler;
+import net.minecraftforge.jarjar.metadata.json.ArtifactVersionSerializer;
+import net.minecraftforge.jarjar.metadata.json.ContainedJarIdentifierSerializer;
+import net.minecraftforge.jarjar.metadata.json.ContainedJarMetadataSerializer;
+import net.minecraftforge.jarjar.metadata.json.ContainedVersionSerializer;
+import net.minecraftforge.jarjar.metadata.json.MetadataSerializer;
+import net.minecraftforge.jarjar.metadata.json.VersionRangeSerializer;
+import org.apache.maven.artifact.versioning.ArtifactVersion;
+import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
+import org.apache.maven.artifact.versioning.InvalidVersionSpecificationException;
+import org.apache.maven.artifact.versioning.VersionRange;
+import org.codehaus.groovy.runtime.InvokerHelper;
+import org.gradle.api.Action;
+import org.gradle.api.DefaultTask;
+import org.gradle.api.artifacts.ConfigurationContainer;
+import org.gradle.api.artifacts.Dependency;
+import org.gradle.api.artifacts.ExternalModuleDependency;
+import org.gradle.api.artifacts.FileCollectionDependency;
+import org.gradle.api.artifacts.MinimalExternalModuleDependency;
+import org.gradle.api.artifacts.ModuleDependency;
+import org.gradle.api.artifacts.ModuleIdentifier;
+import org.gradle.api.artifacts.ModuleVersionIdentifier;
+import org.gradle.api.artifacts.ResolvedArtifact;
+import org.gradle.api.file.ProjectLayout;
+import org.gradle.api.file.RegularFileProperty;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.provider.SetProperty;
+import org.gradle.api.tasks.Input;
+import org.gradle.api.tasks.OutputFile;
+import org.gradle.api.tasks.TaskAction;
+
+import javax.inject.Inject;
+import java.io.File;
+import java.io.IOException;
+import java.io.Serial;
+import java.io.Serializable;
+import java.nio.file.Files;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.zip.ZipFile;
+
+// TODO SUPER SUPER SUPER UGLY, CLEAN UP IN FORGEDEV 7
+@Deprecated(forRemoval = true) // Will be moved to JarJar plugin in ForgeDev 7
+public abstract class JarJarMetadataOptions extends DefaultTask {
+    private static final Gson GSON = new GsonBuilder()
+        .registerTypeAdapter(VersionRange.class, new VersionRangeSerializer())
+        .registerTypeAdapter(ArtifactVersion.class, new ArtifactVersionSerializer())
+        .registerTypeAdapter(DefaultArtifactVersion.class, new ArtifactVersionSerializer())
+        .registerTypeAdapter(ContainedJarIdentifier.class, new ContainedJarIdentifierSerializer())
+        .registerTypeAdapter(ContainedJarMetadata.class, new ContainedJarMetadataSerializer())
+        .registerTypeAdapter(ContainedVersion.class, new ContainedVersionSerializer())
+        .registerTypeAdapter(Metadata.class, new MetadataSerializer())
+        .setPrettyPrinting()
+        .create();
+
+    protected abstract @Input SetProperty<ResolvedDependencyInfoImpl> getResolvedDependencies();
+
+    protected abstract @OutputFile RegularFileProperty getMetadataFile();
+
+    protected abstract @Inject ProjectLayout getLayout();
+
+    // NOTE: I'm not adding a non-provider version. please just use the version catalog entries for now.
+    public void add(Provider<MinimalExternalModuleDependency> dependency, Action<? super ResolvedDependencyInfo> action) {
+        this.getResolvedDependencies().add(dependency.map(d -> {
+            var ret = ResolvedDependencyInfoImpl.from(this.getProject().getConfigurations(), d);
+            action.execute(ret);
+            return ret;
+        }));
+    }
+
+    @Inject
+    public JarJarMetadataOptions() {
+        this.getMetadataFile().convention(this.getLayout().getBuildDirectory().file(this.getName() + "/options.json"));
+    }
+
+    @TaskAction
+    protected void exec() {
+        record ForgeLocaterOptions(String resource, String layer, String id, List<ContainedJarMetadata> deps, ContainedJarMetadata meta, boolean nested) { }
+
+        var resolved = this.getResolvedDependencies().get();
+        var jars = new ArrayList<ForgeLocaterOptions>(resolved.size());
+        for (var dependency : resolved) {
+            var deps = new ArrayList<ContainedJarMetadata>();
+            try (var zip = new ZipFile(dependency.artifact)) {
+                var entry = zip.getEntry("META-INF/jarjar/metadata.json");
+                if (entry != null) {
+                    try (var stream = zip.getInputStream(entry)) {
+                        var meta = MetadataIOHandler.fromStream(stream).orElse(null);
+                        if (meta == null)
+                            throw new IllegalStateException("Corrupt metadata.json in " + dependency.artifact.getAbsolutePath());
+                        for (var dep : meta.jars())
+                            deps.add(new ContainedJarMetadata(dep.identifier(), dep.version(), "", dep.isObfuscated()));
+                    }
+                }
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+            jars.add(new ForgeLocaterOptions(
+                dependency.resource,
+                dependency.layer,
+                dependency.identifier,
+                deps,
+                new ContainedJarMetadata(
+                    new ContainedJarIdentifier(validateGroup(dependency), dependency.module.getName()),
+                    new ContainedVersion(null, parseVersion(dependency)),
+                    Objects.requireNonNull(dependency.path, "Dependency path is unspecified: " + dependency.asString),
+                    false
+                ),
+                dependency.nested
+            ));
+        }
+
+        try {
+            record Meta(List<ForgeLocaterOptions> options){}
+
+            Files.writeString(
+                this.getMetadataFile().getAsFile().get().toPath(),
+                GSON.toJson(new Meta(jars), Meta.class)
+            );
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private String validateGroup(ResolvedDependencyInfoImpl dependency) {
+        try {
+            return Objects.requireNonNull(dependency.module.getGroup());
+        } catch (NullPointerException e) {
+            throw new IllegalArgumentException("Module dependency has no group: " + dependency.asString, e);
+        }
+    }
+
+    private ArtifactVersion parseVersion(ResolvedDependencyInfoImpl resolved) {
+        try {
+            return VersionRange.createFromVersionSpec(Objects.requireNonNull(resolved.version)).getRecommendedVersion();
+        } catch (InvalidVersionSpecificationException e) {
+            throw new IllegalArgumentException("Version is invalid for: " + resolved.asString, e);
+        } catch (NullPointerException e) {
+            throw new IllegalArgumentException("Version is unspecified for: " + resolved.asString, e);
+        }
+    }
+
+    private VersionRange parseVersionRange(ResolvedDependencyInfoImpl dependency) {
+        if (dependency.hasManuallySpecifiedRange) {
+            try {
+                return VersionRange.createFromVersionSpec(dependency.versionRange);
+            } catch (InvalidVersionSpecificationException e) {
+                throw new IllegalArgumentException("Version is invalid for: " + dependency.asString, e);
+            }
+        } else {
+            try {
+                return VersionRange.createFromVersionSpec("[%s,)".formatted(Objects.requireNonNull(dependency.versionRange)));
+            } catch (InvalidVersionSpecificationException e) {
+                throw new IllegalArgumentException("Version range is invalid for: " + dependency.asString, e);
+            } catch (NullPointerException e) {
+                throw new IllegalArgumentException("Version is unspecified for: " + dependency.asString, e);
+            }
+        }
+    }
+
+    public interface ResolvedDependencyInfo {
+        void containedJarMetadata(Action<? super ContainedJarMetadataInfo> action);
+
+        void setResource(String resource);
+
+        void setLayer(String layer);
+
+        void setId(String identifier);
+
+        void setNested(boolean nested);
+
+        interface ContainedJarMetadataInfo {
+            void setGroup(String group);
+
+            void setName(String name);
+
+            void setPath(String version);
+        }
+    }
+
+    static final class ResolvedDependencyInfoImpl implements ResolvedDependencyInfo, ResolvedDependencyInfo.ContainedJarMetadataInfo, Serializable {
+        private static final @Serial long serialVersionUID = -7577318115877822993L;
+
+        final MinimalModuleVersionIdentifier module;
+        final String version;
+        String versionRange;
+        boolean hasManuallySpecifiedRange;
+        boolean nested;
+        final File artifact;
+        String path;
+        String resource;
+        String layer;
+        String identifier;
+        final String asString;
+
+        public ResolvedDependencyInfoImpl(MinimalModuleVersionIdentifier module, String version, File artifact, String asString) {
+            this.module = module;
+            this.version = version;
+            this.artifact = artifact;
+            this.asString = asString;
+        }
+
+        @Override
+        public void containedJarMetadata(Action<? super ContainedJarMetadataInfo> action) {
+            action.execute(this);
+        }
+
+        @Override
+        public void setGroup(String group) {
+            this.module.group = group;
+        }
+
+        @Override
+        public void setName(String name) {
+            this.module.name = name;
+        }
+
+        @Override
+        public void setPath(String path) {
+            this.path = path;
+        }
+
+        @Override
+        public void setResource(String resource) {
+            this.resource = resource;
+        }
+
+        @Override
+        public void setLayer(String layer) {
+            this.layer = layer;
+        }
+
+        @Override
+        public void setId(String identifier) {
+            this.identifier = identifier;
+        }
+
+        @Override
+		public void setNested(boolean nested) {
+			this.nested = nested;
+		}
+
+        static Set<File> getFiles(Set<ResolvedDependencyInfoImpl> resolvedDependencies) {
+            var ret = new HashSet<File>(resolvedDependencies.size());
+            for (var dependency : resolvedDependencies) {
+                ret.add(dependency.artifact);
+            }
+            return ret;
+        }
+
+        static ResolvedDependencyInfoImpl from(ConfigurationContainer configurations, Dependency dependency) {
+            var group = dependency.getGroup();
+            var name = dependency.getName();
+            var version = dependency.getVersion();
+
+            if (dependency instanceof FileCollectionDependency filesDependency) {
+                File artifact;
+                try {
+                    artifact = filesDependency.getFiles().getSingleFile();
+                } catch (IllegalStateException e) {
+                    // TODO fileCollectionDependencyIsNotSingleFile
+                    throw e;
+                }
+
+                return new ResolvedDependencyInfoImpl(
+                    new MinimalModuleVersionIdentifier(group, name, version),
+                    version,
+                    artifact,
+                    filesDependency.toString()
+                );
+            } else if (dependency instanceof ModuleDependency moduleDependency) {
+                moduleDependency = moduleDependency.copy();
+                if (moduleDependency instanceof ExternalModuleDependency externalModuleDependency) {
+                    externalModuleDependency.version(v -> v.strictly(version.toString()));
+                }
+
+                var detachedConfiguration = configurations.detachedConfiguration(moduleDependency);
+                detachedConfiguration.setTransitive(false);
+
+                ResolvedDependencyInfoImpl ret = null;
+                for (var artifact : detachedConfiguration.getResolvedConfiguration().getFirstLevelModuleDependencies().iterator().next().getModuleArtifacts()) {
+                    var fileName = getFileName(artifact);
+                    if (!fileName.endsWith(".jar"))
+                        continue;
+
+                    if (ret != null)
+                        throw new IllegalArgumentException("Module dependency has too many Jar artifacts: " + moduleDependency);
+
+                    ret = new ResolvedDependencyInfoImpl(
+                        new MinimalModuleVersionIdentifier(group, name, artifact.getModuleVersion().getId().getVersion()),
+                        version,
+                        artifact.getFile(),
+                        moduleDependency.toString()
+                    );
+                }
+                if (ret == null)
+                    throw new IllegalArgumentException("Module dependency has no Jar artifacts: " + moduleDependency);
+
+                return ret;
+            } else {
+                throw new IllegalArgumentException("Unsupported dependency type: " + dependency.getClass().getName() + " -- " + dependency);
+            }
+        }
+
+        private static String getFileName(ResolvedArtifact artifact) {
+            try {
+                return InvokerHelper.getProperty(artifact.getId(), "fileName").toString();
+            } catch (Throwable e) {
+                // NOTE: Why not just use this to begin with?
+                // ComponentArtifactIdentifier can have a getFileName() method, which doesn't necessarily resolve the file itself.
+                // This allows us to get the name of the file to be used without asking Gradle to download the file.
+                // So, if a file is not a JAR file, we can check the name without actually downloading it.
+                return artifact.getFile().getName();
+            }
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj == this) return true;
+            if (obj == null || obj.getClass() != this.getClass()) return false;
+            var that = (ResolvedDependencyInfoImpl) obj;
+            return Objects.equals(this.module, that.module) &&
+                Objects.equals(this.version, that.version) &&
+                Objects.equals(this.versionRange, that.versionRange) &&
+                Objects.equals(this.artifact, that.artifact);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(module, version, versionRange, artifact);
+        }
+
+        @Override
+        public String toString() {
+            return "ResolvedDependencyInfo[" +
+                "module=" + module + ", " +
+                "fixedVersion=" + version + ", " +
+                "versionRange=" + versionRange + ", " +
+                "artifact=" + artifact + ']';
+        }
+
+        static final class MinimalModuleVersionIdentifier implements ModuleIdentifier, ModuleVersionIdentifier {
+            private static final @Serial long serialVersionUID = -955346236759069739L;
+
+            private String group;
+            private String name;
+            private final String version;
+
+            @Inject
+            public MinimalModuleVersionIdentifier(String group, String name, String version) {
+                this.group = group;
+                this.name = name;
+                this.version = version;
+            }
+
+            @Override
+            public ModuleIdentifier getModule() {
+                return this;
+            }
+
+            @Override
+            public String getGroup() {
+                return this.group;
+            }
+
+            @Override
+            public String getName() {
+                return this.name;
+            }
+
+            @Override
+            public String getVersion() {
+                return this.version;
+            }
+
+            @Override
+            public boolean equals(Object obj) {
+                return this == obj || obj instanceof MinimalModuleVersionIdentifier o
+                    && Objects.equals(this.group, o.group)
+                    && Objects.equals(this.name, o.name)
+                    && Objects.equals(this.version, o.version);
+            }
+
+            @Override
+            public int hashCode() {
+                return Objects.hash(group, name, version);
+            }
+
+            @Override
+            public String toString() {
+                return "MinimalModuleVersionIdentifier[" +
+                    "group=" + group + ", " +
+                    "name=" + name + ", " +
+                    "version=" + version + ']';
+            }
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/LauncherJson.groovy

@@ -6,6 +6,7 @@ import org.gradle.api.file.ConfigurableFileCollection
 import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.provider.SetProperty
 import org.gradle.api.tasks.*
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
 
 import java.nio.file.Files
 
@@ -16,59 +17,78 @@ abstract class LauncherJson extends DefaultTask {
     @OutputFile abstract RegularFileProperty getOutput()
     @InputFiles abstract ConfigurableFileCollection getInput()
     @Input Map<String, Object> json = new LinkedHashMap<>()
-    @Input @Optional abstract SetProperty<String> getPackedDependencies()
-    
-    @Internal final vanilla = project.project(':mcp').file('build/mcp/downloadJson/version.json')
-    @Internal final timestamp = iso8601Now()
-    @Internal final comment = [
-        "Please do not automate the download and installation of Forge.",
-        "Our efforts are supported by ads from the download page.",
-        "If you MUST automate this, please consider supporting the project through https://www.patreon.com/LexManos/"
-    ]
-    @Internal final id = "${project.rootProject.ext.MC_VERSION}-${project.name}${project.version.substring(project.rootProject.ext.MC_VERSION.length())}"
 
     LauncherJson() {
-        getOutput().convention(project.layout.buildDirectory.file('version.json'))
+        output.convention(project.layout.buildDirectory.file('libs/version.json'))
 
-        dependsOn(':fmlloader:jar', 'universalJar')
-        getInput().from(project.tasks.universalJar.archiveFile,
-                project.project(':fmlloader').jar.archiveFile,
-                vanilla)
-                
-        project.afterEvaluate {
-            packedDependencies.get().forEach {
-                def jarTask = project.rootProject.tasks.findByPath(it)
-                dependsOn(jarTask)
-                input.from jarTask.archiveFile
+        dependsOn(project.tasks.universalJar)
+        input.from(project.tasks.universalJar.archiveFile)
+        input.from(project.configurations.installer)
+        configure {
+            def mc    = project.rootProject.ext.MC_VERSION
+            def forge = project.rootProject.ext.FORGE_VERSION
+            def timestamp = iso8601Now()
+            json.putAll([
+                _comment: [
+                    "Please do not automate the download and installation of Forge.",
+                    "Our efforts are supported by ads from the download page.",
+                    "If you MUST automate this, please consider supporting the project through https://www.patreon.com/LexManos/"
+                ],
+                id: "$mc-$project.name-$forge",
+                time: timestamp,
+                releaseTime: timestamp,
+                inheritsFrom: mc,
+                type: 'release',
+                logging: [:],
+                mainClass: '',
+                libraries: []
+            ] as LinkedHashMap)
+            
+            [
+                project.tasks.universalJar
+            ].forEach { packed ->
+                dependsOn(packed)
+                input.from packed.archiveFile
             }
+            
+            def patched = project.tasks.applyClientBinPatches
+            dependsOn(patched)
+            input.from patched.output
         }
     }
 
     @TaskAction
     protected void exec() {
-        if (!json.libraries)
-            json.libraries = []
-        def libs = [:]
-        getArtifacts(project, project.configurations.installer, false).each { key, lib -> libs[key] = lib }
-        getArtifacts(project, project.configurations.moduleonly, false).each { key, lib -> libs[key] = lib }
-
-        packedDependencies.get().collect{ project.rootProject.tasks.findByPath(it) }.forEach {
-            def path = Util.getMavenPath(it)
-            def key = Util.getMavenDep(it)
-            
-            libs[key] = [
-                name: key,
-                downloads: [
-                    artifact: [
-                        path: path,
-                        url: "https://maven.minecraftforge.net/${path}",
-                        sha1: it.archiveFile.get().asFile.sha1(),
-                        size: it.archiveFile.get().asFile.length()
-                    ]
+        var packed = (AbstractArchiveTask) project.tasks.universalJar
+        def info = Util.getMavenInfoFromTask(packed)
+        json.libraries.add([
+            name: info.name,
+            downloads: [
+                artifact: [
+                    path: info.path,
+                    url: "https://maven.minecraftforge.net/$info.path",
+                    sha1: packed.archiveFile.get().asFile.sha1(),
+                    size: packed.archiveFile.get().asFile.length()
                 ]
             ]
-        }
-        libs.each { key, lib -> json.libraries.add(lib) }
+        ])
+
+        var classifier = 'client'
+        var genned = project.tasks.applyClientBinPatches
+        info = Util.getMavenInfoFromTask(genned, classifier)
+        json.libraries.add([
+            name: info.name,
+            downloads: [
+                artifact: [
+                    path: info.path,
+                    url: "",
+                    sha1: genned.output.get().asFile.sha1(),
+                    size: genned.output.get().asFile.length()
+                ]
+            ]
+        ])
+
+        json.libraries.addAll(getArtifacts(project.configurations.installer).values())
         Files.writeString(output.get().asFile.toPath(), new JsonBuilder(json).toPrettyString())
     }
 }

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/MergeJars.groovy

@@ -0,0 +1,46 @@
+package net.minecraftforge.forge.tasks
+
+import groovy.transform.CompileStatic
+import org.apache.commons.io.IOUtils
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.OutputFile
+import org.gradle.api.tasks.TaskAction
+
+import java.util.zip.ZipEntry
+import java.util.zip.ZipInputStream
+import java.util.zip.ZipOutputStream
+
+@CompileStatic
+abstract class MergeJars extends DefaultTask {
+    MergeJars() {
+        output.convention(project.layout.buildDirectory.dir(name).map { it.file('output.jar') })
+    }
+
+    @TaskAction
+    void run() {
+        def jars = inputJars.files
+
+        try (ZipOutputStream zout = new ZipOutputStream(new FileOutputStream(output.get().asFile))) {
+            for (def jar : jars) {
+                try (ZipInputStream zin = new ZipInputStream(new FileInputStream(jar))) {
+                    ZipEntry entry
+                    while ((entry = zin.getNextEntry()) !== null) {
+                        ZipEntry _new = new ZipEntry(entry.getName())
+                        _new.setTime(0) //SHOULD be the same time as the main entry, but NOOOO _new.setTime(entry.getTime()) throws DateTimeException, so you get 0, screw you!
+                        zout.putNextEntry(_new)
+                        IOUtils.copy(zin, zout)
+                    }
+                }
+            }
+        }
+    }
+
+    @InputFiles
+    abstract ConfigurableFileCollection getInputJars()
+
+    @OutputFile
+    abstract RegularFileProperty getOutput()
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/ObjectTarget.groovy

@@ -27,6 +27,6 @@ public class ObjectTarget implements Comparable<ObjectTarget> {
     
     @Override
     int compareTo(ObjectTarget o) {
-        return toString().compareTo(o.toString())
+        return toString() <=> o.toString()
     }
 }

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/SetupCheckJarCompatibility.groovy

@@ -0,0 +1,47 @@
+package net.minecraftforge.forge.tasks
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.artifacts.Dependency
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.Optional
+import org.gradle.api.tasks.OutputFile
+import org.gradle.api.tasks.TaskAction
+
+import java.nio.file.Files
+import java.nio.file.StandardCopyOption
+
+abstract class SetupCheckJarCompatibility extends DefaultTask {
+    SetupCheckJarCompatibility() {
+        group = 'jar compatibility'
+        onlyIf {
+            inputVersion.getOrNull() !== null
+        }
+        outputs.upToDateWhen { false } // Never up to date, because this setup task should always run
+
+        baseBinPatchesOutput.convention(project.layout.buildDirectory.dir(name).map { it.file('joined.lzma') })
+    }
+
+    @TaskAction
+    void run() {
+        def inputVersion = inputVersion.get()
+
+        def baseForgeUserdev = project.layout.buildDirectory.dir(name).map { it.file("forge-${inputVersion}-userdev.jar") }.get().asFile
+        project.rootProject.extensions.download.run {
+            src "https://maven.minecraftforge.net/net/minecraftforge/forge/${inputVersion}/forge-${inputVersion}-userdev.jar"
+            dest baseForgeUserdev
+        }
+
+        def joinedLzma = project.zipTree(baseForgeUserdev).matching { it.include('joined.lzma') }.singleFile
+
+        Files.copy(joinedLzma.toPath(), baseBinPatchesOutput.get().asFile.toPath(), StandardCopyOption.REPLACE_EXISTING)
+    }
+
+    @Input
+    @Optional
+    abstract Property<String> getInputVersion()
+
+    @OutputFile
+    abstract RegularFileProperty getBaseBinPatchesOutput()
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/TeamcityRequests.groovy

@@ -0,0 +1,74 @@
+package net.minecraftforge.forge.tasks
+
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
+import groovy.transform.CompileStatic
+import org.eclipse.jgit.api.Git
+
+import javax.annotation.Nullable
+import java.util.stream.Collectors
+
+@CompileStatic
+class TeamcityRequests {
+    public static final Gson GSON = new Gson()
+
+    @Nullable
+    static <T> T jsonRequest(TypeToken<T> clazz, String url) throws Exception {
+        final HttpURLConnection conn = (HttpURLConnection) URI.create(url).toURL().openConnection()
+        conn.setRequestProperty('Accept', 'application/json')
+        conn.setReadTimeout(5 * 1000)
+        conn.setConnectTimeout(5 * 1000)
+        conn.connect()
+
+        if (conn.responseCode !== 200) {
+            return null
+        }
+
+        try (final InputStream is = conn.getInputStream()) {
+            GSON.fromJson(new InputStreamReader(is), clazz.getType())
+        }
+    }
+
+    @Nullable
+    static Map<String, Build> buildsByCommit() throws IOException {
+        final Map<String, Build> builds = [:]
+        jsonRequest(new TypeToken<Builds>() {}, 'https://teamcity.minecraftforge.net/guestAuth/app/rest/builds?fields=build:(revisions,number)&locator=buildType:(id:MinecraftForge_MinecraftForge_MinecraftForge_MinecraftForge__Build),defaultFilter:false,count:300,status:SUCCESS')
+                ?.build?.forEach {
+            it.revisions.revision.each { rev -> builds[rev.version] = it }
+        }
+        return builds
+    }
+
+    @Nullable
+    static String attemptFindBase(File gitPath) {
+        try (final git = Git.open(gitPath)) {
+            final Map<String, Build> buildByCommit = buildsByCommit()
+            for (final commit in git.log().setMaxCount(100).call()) {
+                // Find the first commit which was built on CI
+                final build = buildByCommit[commit.id.name]
+                if (build) {
+                    return build.number
+                }
+            }
+        } catch (Exception ignored) {}
+        return null
+    }
+
+    static final class Builds {
+        public List<Build> build
+    }
+
+    static final class Build {
+        public String number
+        public Revisions revisions
+    }
+
+    static final class Revisions {
+        public int count
+        public List<Revision> revision
+    }
+
+    static final class Revision {
+        public String version
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/Util.groovy

@@ -2,144 +2,229 @@ package net.minecraftforge.forge.tasks
 
 import groovy.json.JsonBuilder
 import groovy.json.JsonSlurper
+import groovy.transform.CompileStatic
+import groovy.transform.stc.ClosureParams
+import groovy.transform.stc.SimpleType
+import org.gradle.api.Project
+import org.gradle.api.Task
+import org.gradle.api.artifacts.Configuration
+import org.gradle.api.artifacts.ResolvedArtifact
+import org.gradle.api.tasks.bundling.AbstractArchiveTask
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.Opcodes
+import org.objectweb.asm.tree.ClassNode
 
-import java.io.File
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpResponse
 import java.security.MessageDigest
 import java.text.SimpleDateFormat
-import java.util.Date
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.Semaphore
+import java.util.zip.ZipEntry
+import java.util.zip.ZipInputStream
 
-public class Util {
-	static void init() {
-		File.metaClass.sha1 = { ->
-			MessageDigest md = MessageDigest.getInstance('SHA-1')
-			delegate.eachByte 4096, {bytes, size ->
-				md.update(bytes, 0, size)
-			}
-			return md.digest().collect {String.format "%02x", it}.join()
-		}
+final class Util {
+    public static final int ASM_LEVEL = Opcodes.ASM9
+    private static final HttpClient HTTP = HttpClient.newBuilder().build()
+
+    static void init() {
+        File.metaClass.sha1 = { ->
+            MessageDigest md = MessageDigest.getInstance('SHA-1')
+            delegate.eachByte(4096) { byte[] bytes, int size ->
+                md.update(bytes, 0, size)
+            }
+            return md.digest().collect(this.&toHex).join('')
+        }
         File.metaClass.getSha1 = { !delegate.exists() ? null : delegate.sha1() }
-	
-		File.metaClass.json = { -> new JsonSlurper().parseText(delegate.text) }
+        File.metaClass.sha256 = { ->
+            MessageDigest md = MessageDigest.getInstance('SHA-256')
+            delegate.eachByte(4096) { byte[] bytes, int size ->
+                md.update(bytes, 0, size)
+            }
+            return md.digest().collect(this.&toHex).join('')
+        }
+        File.metaClass.getSha256 = { !delegate.exists() ? null : delegate.sha256() }
+
+        File.metaClass.json = { -> new JsonSlurper().parseText(delegate.text) }
         File.metaClass.getJson = { return delegate.exists() ? new JsonSlurper().parse(delegate) : [:] }
         File.metaClass.setJson = { json -> delegate.text = new JsonBuilder(json).toPrettyString() }
-		
-		Date.metaClass.iso8601 = { ->
-			def format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ")
-			def result = format.format(delegate)
-			return result[0..21] + ':' + result[22..-1]
-		}
-        
+
+        Date.metaClass.iso8601 = { ->
+            var format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ")
+            var result = format.format(delegate)
+            return result[0..21] + ':' + result[22..-1]
+        }
+
         String.metaClass.rsplit = { String del, int limit = -1 ->
-            def lst = new ArrayList()
-            def x = 0, idx
-            def tmp = delegate
-            while ((idx = tmp.lastIndexOf(del)) != -1 && (limit == -1 || x++ < limit)) {
+            var lst = new ArrayList<String>()
+            int x = 0
+            int idx
+            String tmp = delegate
+            while ((idx = tmp.lastIndexOf(del)) != -1 && (limit === -1 || x++ < limit)) {
                 lst.add(0, tmp.substring(idx + del.length(), tmp.length()))
                 tmp = tmp.substring(0, idx)
             }
             lst.add(0, tmp)
             return lst
         }
-	}
-	
-	public static String[] getClasspath(project, libs, artifact) {
-		def ret = []
-		artifactTree(project, artifact).each { key, lib ->
-			libs[lib.name] = lib
-			if (lib.name != artifact)
-				ret.add(lib.name)
-		}
-		return ret
-	}
-	
-	public static def getArtifacts(project, config, classifiers) {
-		def ret = [:]
-		config.resolvedConfiguration.resolvedArtifacts.each {
-			def art = [
-				group: it.moduleVersion.id.group,
-				name: it.moduleVersion.id.name,
-				version: it.moduleVersion.id.version,
-				classifier: it.classifier,
-				extension: it.extension,
-				file: it.file
-			]
-			def key = art.group + ':' + art.name
-			def folder = "${art.group.replace('.', '/')}/${art.name}/${art.version}/"
-			def filename = "${art.name}-${art.version}"
-			if (art.classifier != null)
-				filename += "-${art.classifier}"
-			filename += ".${art.extension}"
-			def path = "${folder}${filename}"
-			def url = "https://libraries.minecraft.net/${path}"
-			if (!checkExists(url)) {
-				url = "https://maven.minecraftforge.net/${path}"
-			}
-			//TODO remove when Mojang launcher is updated
-			if (!classifiers && art.classifier != null) { 
-				//Mojang launcher doesn't currently support classifiers, so... move it to part of the version, and force the extension to 'jar'
-				// However, keep the path normal so that our mirror system works.
-				art.version = "${art.version}-${art.classifier}"
-				art.classifier = null
-				art.extension = 'jar'
-			}
-			ret[key] = [
-				name: "${art.group}:${art.name}:${art.version}" + (art.classifier == null ? '' : ":${art.classifier}") + (art.extension == 'jar' ? '' : "@${art.extension}"),
-				downloads: [
-					artifact: [
-						path: path,
-						url: url,
-						sha1: sha1(art.file),
-						size: art.file.length()
-					]
-				]
-			]
-		}
-		return ret
-	}
-    
-    public static def getMavenPath(task) {        
-        def classifier = task.archiveClassifier.get()
-        def dep = "${task.project.group}:${task.project.name}:${task.project.version}" + (classifier == '' ? '' : ':' + classifier)
-        return "${task.project.group.replace('.', '/')}/${task.project.name}/${task.project.version}/${task.project.name}-${task.project.version}".toString() + (classifier == '' ? '' : '-' + classifier) + '.jar'
-    }
-    
-    public static def getMavenDep(task) {        
-        def classifier = task.archiveClassifier.get()
-        return "${task.project.group}:${task.project.name}:${task.project.version}" + (classifier == '' ? '' : ':' + classifier)
     }
 
-	public static def iso8601Now() { new Date().iso8601() }
+    static String[] getClasspath(Project project, Map libs, String artifact) {
+        def ret = []
+        artifactTree(project, artifact).each { key, lib ->
+            libs[lib.name] = lib
+            if (lib.name != artifact)
+                ret.add(lib.name)
+        }
+        return ret
+    }
 
-	public static def sha1(file) {
-		MessageDigest md = MessageDigest.getInstance('SHA-1')
-		file.eachByte 4096, {bytes, size ->
-			md.update(bytes, 0, size)
-		}
-		return md.digest().collect {String.format "%02x", it}.join()
-	}
+    @CompileStatic
+    static Map getArtifacts(Configuration config) {
+        var ret = [:]
+        var semaphore = new Semaphore(1, true)
+        config.resolvedConfiguration.resolvedArtifacts.parallelStream().forEachOrdered(dep -> {
+            var info = getMavenInfoFromDep(dep)
+            var domain = 'libraries.minecraft.net'
+            var url = "https://$domain/$info.path"
+            if (!checkExists(url))
+                url.values[0] = 'maven.minecraftforge.net'
 
-	private static def artifactTree(project, artifact) {
-		if (!project.ext.has('tree_resolver'))
-			project.ext.tree_resolver = 1
-		def cfg = project.configurations.create('tree_resolver_' + project.ext.tree_resolver++)
-		def dep = project.dependencies.create(artifact)
-		cfg.dependencies.add(dep)
-		def files = cfg.resolve()
-		return getArtifacts(project, cfg, true)
-	}
-	
-	private static boolean checkExists(url) {
-		try {
-			def code = new URL(url).openConnection().with {
-				requestMethod = 'HEAD'
-				connect()
-				responseCode
-			}
-			return code == 200
-		} catch (Exception e) {
-			if (e.toString().contains('unable to find valid certification path to requested target'))
-				throw new RuntimeException('Failed to connect to ' + url + ': Missing certificate root authority, try updating java')
-			throw e
-		}
-	}
-}
+            var sha1 = sha1(dep.file)
+
+            semaphore.acquire()
+            ret[info.key] = [
+                name: info.name,
+                downloads: [
+                    artifact: [
+                        path: info.path,
+                        url: url.toString(),
+                        sha1: sha1,
+                        size: dep.file.length()
+                    ]
+                ]
+            ]
+            semaphore.release()
+        })
+        return ret
+    }
+
+    @CompileStatic
+    static Map getMavenInfoFromDep(ResolvedArtifact dep) {
+        return getMavenInfoFromMap([
+            group: dep.moduleVersion.id.group,
+            name: dep.moduleVersion.id.name,
+            version: dep.moduleVersion.id.version,
+            classifier: dep.classifier,
+            extension: dep.extension
+        ])
+    }
+
+    @CompileStatic
+    static Map getMavenInfoFromTask(AbstractArchiveTask task) {
+        return getMavenInfoFromMap([
+            group: task.project.group.toString(),
+            name: task.project.name,
+            version: task.project.version.toString(),
+            classifier: task.archiveClassifier.get(),
+            extension: task.archiveExtension.get()
+        ])
+    }
+
+    @CompileStatic
+    static Map getMavenInfoFromTask(Task task, String classifier) {
+        return getMavenInfoFromMap([
+            group: task.project.group.toString(),
+            name: task.project.name,
+            version: task.project.version.toString(),
+            classifier: classifier,
+            extension: 'jar'
+        ])
+    }
+
+    @CompileStatic
+    private static Map getMavenInfoFromMap(Map<String, String> art) {
+        var key = "$art.group:$art.name"
+        var name = "$art.group:$art.name:$art.version"
+        var path = "${art.group.replace('.', '/')}/$art.name/$art.version/$art.name-$art.version"
+        if (art.classifier !== null) {
+            name += ":$art.classifier"
+            path += "-$art.classifier"
+        }
+        if ('jar' != art.extension) {
+            name += "@$art.extension"
+            path += ".$art.extension"
+        } else {
+            path += ".jar"
+        }
+        return [
+            key: key.toString(),
+            name: name.toString(),
+            path: path.toString(),
+            art: art
+        ]
+    }
+
+    static String iso8601Now() { new Date().iso8601() }
+
+    @CompileStatic
+    static String sha1(File file) {
+        MessageDigest md = MessageDigest.getInstance('SHA-1')
+        file.eachByte(4096) { byte[] bytes, int size ->
+            md.update(bytes, 0, size)
+        }
+        return md.digest().collect(this.&toHex).join('')
+    }
+
+    @CompileStatic
+    private static String toHex(byte bite) {
+        return String.format('%02x', bite)
+    }
+
+    private static Map artifactTree(Project project, String artifact, boolean transitive = true) {
+        if (!project.ext.has('tree_resolver'))
+            project.ext.tree_resolver = 1
+        def cfg = project.configurations.create('tree_resolver_' + project.ext.tree_resolver++)
+        cfg.transitive = transitive
+        def dep = project.dependencies.create(artifact)
+        cfg.dependencies.add(dep)
+        def files = cfg.resolve()
+        return getArtifacts(cfg)
+    }
+
+    @CompileStatic
+    static boolean checkExists(String url) {
+        try {
+            return HTTP.send(HttpRequest.newBuilder(new URI(url))
+                    .method('HEAD', HttpRequest.BodyPublishers.noBody()).build(), HttpResponse.BodyHandlers.discarding()
+            ).statusCode() === 200
+        } catch (Exception e) {
+            if (e.toString().contains('unable to find valid certification path to requested target'))
+                throw new RuntimeException("Failed to connect to $url: Missing certificate root authority, try updating Java")
+            throw e
+        }
+    }
+
+    static String getLatestForgeVersion(String mcVersion) {
+        final json = new JsonSlurper().parseText(new URL('https://files.minecraftforge.net/net/minecraftforge/forge/promotions_slim.json').getText('UTF-8'))
+        final ver = json.promos["$mcVersion-latest"]
+        ver === null ? null : (mcVersion + '-' + ver)
+    }
+
+    @CompileStatic
+    static void processClassNodes(File file, @ClosureParams(value = SimpleType, options = 'org.objectweb.asm.tree.ClassNode') Closure process) {
+        file.withInputStream { i ->
+            new ZipInputStream(i).withCloseable { zin ->
+                ZipEntry zein
+                while ((zein = zin.nextEntry) !== null) {
+                    if (zein.name.endsWith('.class')) {
+                        var node = new ClassNode(ASM_LEVEL)
+                        new ClassReader(zin).accept(node, 0)
+                        process(node)
+                    }
+                }
+            }
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/ValidateDeprecations.groovy

@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.forge.tasks
+
+import groovy.transform.CompileStatic
+import net.minecraftforge.srgutils.MinecraftVersion
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.TaskAction
+import org.objectweb.asm.tree.AnnotationNode
+import org.objectweb.asm.tree.ClassNode
+
+abstract class ValidateDeprecations extends DefaultTask {
+    @InputFile
+    abstract RegularFileProperty getInput()
+
+    @Input
+    abstract Property<String> getMcVersion()
+
+    ValidateDeprecations() {
+        this.onlyIf { !System.env.TEAMCITY_VERSION }
+    }
+
+    @TaskAction
+    protected void exec() {
+        var mcVer = MinecraftVersion.from(mcVersion.get())
+        List<String> errors = []
+
+        Util.processClassNodes(input.get().asFile) {
+            processNode(mcVer, errors, it)
+        }
+
+        if (!errors.isEmpty()) {
+            errors.forEach {
+                this.logger.error("Deprecated ${it[0]} is marked for removal in ${it[1]} but is not yet removed")
+            }
+            throw new IllegalStateException("Found deprecated members marked for removal but not yet removed in ${mcVer}; see log for details")
+        }
+    }
+
+    protected processNode(MinecraftVersion mcVer, List<String> errors, ClassNode node) {
+        node.visibleAnnotations?.each { annotation ->
+            ValidateDeprecations.processAnnotations(annotation, mcVer, errors) {
+                "class ${node.name}"
+            }
+        }
+        node.fields?.each { field ->
+            field.visibleAnnotations?.each { annotation ->
+                ValidateDeprecations.processAnnotations(annotation, mcVer, errors) {
+                    "field ${node.name}#${field.name}"
+                }
+            }
+        }
+        node.methods?.each { method ->
+            method.visibleAnnotations?.each { annotation ->
+                ValidateDeprecations.processAnnotations(annotation, mcVer, errors) {
+                    "method ${node.name}#${method.name}${method.desc}"
+                }
+            }
+        }
+    }
+
+    private static void processAnnotations(AnnotationNode annotation, MinecraftVersion mcVer, List<String> errors, Closure<String> context) {
+        def values = annotation.values
+        if (values === null)
+            return
+        int forRemoval = values.indexOf('forRemoval')
+        int since = values.indexOf('since')
+        if (annotation.desc == 'Ljava/lang/Deprecated;' && forRemoval !== -1 && since !== -1 && values.size() >= 4 && values[forRemoval + 1] === true) {
+            def oldVersion = MinecraftVersion.from(values[since + 1])
+            int[] split = ValidateDeprecations.splitDots(oldVersion.toString())
+            if (split.length < 2)
+                return
+            def removeVersion = MinecraftVersion.from("${split[0]}.${split[1] + 1}")
+            if (removeVersion <= mcVer)
+                errors.add([context(), removeVersion])
+        }
+    }
+
+    @CompileStatic
+    private static int[] splitDots(String version) {
+        String[] pts = version.split('\\.')
+        int[] values = new int[pts.length]
+        for (int x = 0; x < pts.length; x++)
+            values[x] = Integer.parseInt(pts[x])
+        return values
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckATs.groovy

@@ -0,0 +1,282 @@
+package net.minecraftforge.forge.tasks.checks
+
+import groovy.transform.CompileStatic
+import groovy.transform.TupleConstructor
+import net.minecraftforge.forge.tasks.InheritanceData
+import net.minecraftforge.srgutils.IMappingFile
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFile
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.Optional
+import org.objectweb.asm.Opcodes
+
+@CompileStatic
+abstract class CheckATs extends CheckTask {
+
+    @InputFile abstract RegularFileProperty getInheritance()
+    @InputFiles abstract ConfigurableFileCollection getAts()
+
+    @Override
+    void check(Reporter reporter, boolean fix) {
+        final inheritance = InheritanceData.parse(this.inheritance.get().asFile)
+
+        ats.each {
+            final lines = process(it, reporter, inheritance)
+            if (fix) {
+                it.text = joinBack(lines, inheritance).join('\n')
+            }
+        }
+    }
+
+    private static TreeMap<String, ATParser.Entry> process(File file, Reporter reporter, Map<String, InheritanceData> inheritance) {
+        final TreeMap<String, ATParser.Entry> lines = ATParser.parse(file.readLines(), reporter)
+        final Map<String, ATParser.Entry> constructorGroups = [:]
+
+        final itr = lines.entrySet().iterator()
+        final toRemove = []
+        while (itr.hasNext()) {
+            final next = itr.next()
+            String key = next.key
+            final entry = next.value
+            if (entry === null) continue
+
+            final binaryName = entry.cls.replaceAll('\\.', '/')
+
+            // Process Groups, this will remove any entries outside the group that is covered by the group
+            if (entry.group) {
+                final jcls = inheritance[binaryName]
+                if (jcls === null) {
+                    itr.remove()
+                    reporter.report("Invalid group: $key")
+                } else if ('*' == entry.desc) {
+                    if (!jcls.fields) {
+                        itr.remove()
+                        reporter.report("Invalid group, class has no fields: $key")
+                    } else {
+                        jcls.fields.each { field, value ->
+                            final fkey = entry.cls + ' ' + field
+                            if (accessLevel(value.access) < accessStr(entry.modifier)) {
+                                if (lines.containsKey(fkey)) {
+                                    toRemove.add(fkey)
+                                } else if (!entry.existing.contains(fkey)) {
+                                    reporter.report("Missing group entry: $fkey")
+                                }
+                                entry.children.add(fkey)
+                            } else if (lines.containsKey(fkey)) {
+                                toRemove.add(fkey)
+                                reporter.report("Found invalid group entry: $fkey")
+                            }
+                        }
+                        entry.existing.findAll { it !in entry.children }.each { println('Removed: ' + it) }
+                    }
+                } else if ('*()' == entry.desc) {
+                    if (!jcls.methods) {
+                        itr.remove()
+                        reporter.report("Invalid group, class has no methods: $key")
+                    } else {
+                        jcls.methods.each { mtd, value ->
+                            if (mtd.startsWith('<clinit>') || mtd.startsWith('lambda$')) return
+                            key = entry.cls + ' ' + mtd.replace(' ', '')
+                            if (accessLevel(value.access) < accessStr(entry.modifier)) {
+                                if (lines.containsKey(key)) {
+                                    toRemove.add(key)
+                                } else if (!entry.existing.contains(key)) {
+                                    reporter.report("Missing group entry: $key")
+                                }
+                                entry.children.add(key)
+                            } else if (lines.containsKey(key)) {
+                                toRemove.add(key)
+                                reporter.report("Found invalid group entry: $key")
+                            }
+                        }
+                        entry.existing.findAll { it !in entry.children }.each { println('Removed: ' + it) }
+                    }
+                } else if ('<init>' == entry.desc) { //Make all public non-abstract subclasses
+                    constructorGroups.put(binaryName, entry)
+                }
+            }
+
+            // Process normal lines, remove invalid and remove narrowing
+            else {
+                def jcls = inheritance.get(binaryName)
+                if (jcls === null) {
+                    itr.remove()
+                    reporter.report("Invalid: $key")
+                } else if (entry.desc == '') {
+                    if (accessLevel(jcls.access) > accessStr(entry.modifier) && (entry.comment === null || !entry.comment.startsWith('#force '))) {
+                        itr.remove()
+                        reporter.report("Invalid Narrowing: $key")
+                    }
+                } else if (!entry.desc.contains('(')) {
+                    if (!jcls.fields || !jcls.fields.containsKey(entry.desc)) {
+                        itr.remove()
+                        reporter.report("Invalid: $key")
+                    } else {
+                        final value = jcls.fields[entry.desc]
+                        if (accessLevel(value.access) > accessStr(entry.modifier) && (entry.comment === null || !entry.comment.startsWith('#force '))) {
+                            itr.remove()
+                            reporter.report("Invalid Narrowing: $key - ${entry.comment}")
+                        }
+                    }
+                } else {
+                    final jdesc = entry.desc.replace('(', ' (')
+                    if (!jcls.methods || !jcls.methods.containsKey(jdesc)) {
+                        itr.remove()
+                        reporter.report("Invalid: $key")
+                    } else {
+                        final value = jcls.methods[jdesc]
+                        if (accessLevel(value.access) > accessStr(entry.modifier) && (entry.comment === null || !entry.comment.startsWith('#force '))) {
+                            itr.remove()
+                            reporter.report("Invalid Narrowing: $key")
+                        }
+                    }
+                }
+            }
+        }
+
+        inheritance.each { tcls, value ->
+            if (!value.methods || ((value.access & Opcodes.ACC_ABSTRACT) !== 0)) return
+            String parent = tcls
+            while (parent !== null) {
+                constructorGroups[parent]?.tap { entry ->
+                    value.methods.each { mtd, v ->
+                        if (mtd.startsWith('<init>')) {
+                            final child = tcls.replaceAll('/', '\\.') + ' ' + mtd.replace(' ', '')
+                            if (accessLevel(v.access) < 3) {
+                                if (lines.containsKey(child)) {
+                                    toRemove.add(child)
+                                } else if (child !in entry.existing) {
+                                    reporter.report("Missing group entry: $child")
+                                }
+                                entry.children.add(child)
+                            } else if (lines.containsKey(child)) {
+                                toRemove.add(child)
+                                reporter.report("Found invalid group entry: $child")
+                            }
+                        }
+                    }
+                }
+                parent = inheritance[parent]?.superName
+            }
+        }
+        constructorGroups.values().each { entry -> entry.existing.findAll { it !in entry.children }.each{  reporter.report("Found invalid group entry: $it") } }
+
+        toRemove.each(lines.&remove)
+
+        return lines
+    }
+
+    private static List<String> joinBack(TreeMap<String, ATParser.Entry> lines, Map<String, InheritanceData> inheritance) {
+        final data = [] as List<String>
+        lines.each { key, value ->
+            if (!value.group) {
+                def comment = null //value.comment
+                data.add(value.modifier + ' ' + key + (comment ? ' ' + comment : ''))
+            } else {
+                data.add(('#group ' + value.modifier + ' ' + key + ' ' + (value.comment ?: '')).trim())
+                value.children.each {
+                    final line = value.modifier + ' ' + it
+                    final entry = ATParser.parseEntry(line)
+                    final comment = null //entry.comment
+                    data.add(line + (comment ? ' ' + comment : ''))
+                }
+                data.add('#endgroup')
+            }
+        }
+        return data
+    }
+
+    static int accessStr(String access) {
+        if (access.endsWith('-f') || access.endsWith('+f')) return 4
+        switch (access.toLowerCase()) {
+            case 'public':    return 3
+            case 'protected': return 2
+            case 'default':   return 1
+            case 'private':   return 0
+            default:          return -1
+        }
+    }
+
+    static int accessLevel(int access) {
+        if ((access & Opcodes.ACC_PUBLIC)    !== 0) return 3
+        if ((access & Opcodes.ACC_PROTECTED) !== 0) return 2
+        if ((access & Opcodes.ACC_PRIVATE)   !== 0) return 0
+        return 1
+    }
+}
+
+@CompileStatic
+class ATParser {
+    static TreeMap<String, Entry> parse(List<String> lines, CheckTask.Reporter reporter) {
+        TreeMap<String, Entry> outLines = new TreeMap<>()
+        Entry group = null
+        for (final line : lines) {
+            if (line.isEmpty()) continue
+            if (line.startsWith('#group ')) {
+                final entry = parseEntry(line.substring(7))
+
+                if (entry.desc != '*' && entry.desc != '*()' && entry.desc != '<init>') {
+                    reporter.report("Invalid group: $line", false)
+                }
+
+                entry.group = true
+                entry.children = []
+                entry.existing = []
+
+                group = entry
+
+                if (outLines.containsKey(entry.key)) {
+                    reporter.report("Duplicate group: $line", false)
+                }
+
+                outLines[entry.key] = group
+            } else if (group !== null) {
+                if (line.startsWith('#endgroup')) {
+                    group = null
+                } else {
+                    final key = parseEntry(line).key
+                    group.existing.add(key)
+                }
+            } else if (line.startsWith('#endgroup')) {
+                reporter.report("Invalid group ending: $line", false)
+            } else if (line.startsWith('#')) {
+                //Nom
+            } else {
+                final entry = parseEntry(line)
+                if (outLines.containsKey(entry.key)) {
+                    reporter.report("Found duplicate: $line")
+                    continue
+                }
+                outLines[entry.key] = entry
+            }
+        }
+        return outLines
+    }
+
+    static Entry parseEntry(String line) {
+        final idx = line.indexOf('#')
+        final String comment = idx === -1 ? null : line.substring(idx)
+        if (idx !== -1) line = line.substring(0, idx - 1)
+        final data = (line.trim() + '     ').split(' ', -1)
+    	data[1] = data[1].replaceAll('/', '.') // Convert to Source names, internal names are fine by spec, but not supported by old AST based AT implementations.
+        new Entry(data[0], data[1], data[2], comment)
+    }
+
+    @TupleConstructor
+    static final class Entry {
+        String modifier, cls, desc, comment
+
+        Set<String> existing
+        TreeSet<String> children
+        boolean group = false
+
+        @Lazy
+        String key = {cls + (desc.isEmpty() ? '' : ' ' + desc)}()
+
+        Object getAt(String key) {
+            return getProperty(key)
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckExcs.groovy

@@ -0,0 +1,95 @@
+package net.minecraftforge.forge.tasks.checks
+
+import net.minecraftforge.forge.tasks.Util
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.InputFiles
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.ClassVisitor
+import org.objectweb.asm.MethodVisitor
+import org.objectweb.asm.Type
+
+import java.util.zip.ZipEntry
+import java.util.zip.ZipInputStream
+
+abstract class CheckExcs extends CheckTask {
+
+    @InputFile abstract RegularFileProperty getBinary()
+    @InputFiles abstract ConfigurableFileCollection getExcs()
+
+    @Override
+    void check(Reporter reporter, boolean fix) {
+        final Set<String> known = []
+        collectKnown(known)
+
+        excs.each { f ->
+            final lines = []
+            f.eachLine { line ->
+                int idx = line.indexOf('#')
+                if (idx === 0 || line.isEmpty()) {
+                    return
+                }
+
+                if (idx !== -1) line = line.substring(0, idx - 1)
+
+                if (!line.contains('=')) {
+                    reporter.report("Invalid: $line")
+                    return
+                }
+
+                def (String key, String value) = line.split('=', 2)
+                if (!known.contains(key)) {
+                    reporter.report("Unknown: $line")
+                    return
+                }
+
+                String desc = key.split('\\.', 2)[1]
+                if (!desc.contains('(')) {
+                    reporter.report("Invalid: $line")
+                    return
+                }
+                desc = '(' + desc.split('\\(', 2)[1]
+
+                def (exceptions, String args) = value.contains('|') ? value.split('|', 2) : [value, '']
+
+                if (args.split(',').length !== Type.getArgumentTypes(desc).length) {
+                    reporter.report("Invalid: $line")
+                    return
+                }
+                lines.add(line)
+
+                return
+            }
+
+            if (fix) f.text = lines.sort().join('\n')
+        }
+    }
+
+    private void collectKnown(Collection<String> known) {
+        binary.get().asFile.withInputStream { i ->
+            new ZipInputStream(i).withCloseable { zin ->
+                final visitor = new ClassVisitor(Util.ASM_LEVEL) {
+                    private String cls
+                    @Override
+                    void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+                        this.cls = name
+                    }
+
+                    @Override
+                    MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
+                        known.add(this.cls + '.' + name + descriptor)
+                        super.visitMethod(access, name, descriptor, signature, exceptions)
+                    }
+                }
+                ZipEntry zein
+                while ((zein = zin.nextEntry) !== null) {
+                    if (zein.name.endsWith('.class')) {
+                        ClassReader reader = new ClassReader(zin)
+                        reader.accept(visitor, ClassReader.SKIP_CODE | ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES)
+                    }
+                }
+            }
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckMode.groovy

@@ -0,0 +1,11 @@
+package net.minecraftforge.forge.tasks.checks
+
+import groovy.transform.CompileStatic
+
+@CompileStatic
+enum CheckMode {
+    CHECK,
+    FIX
+
+    CheckMode() {}
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckPatches.groovy

@@ -0,0 +1,182 @@
+package net.minecraftforge.forge.tasks.checks
+
+import groovy.transform.CompileStatic
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.provider.ListProperty
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputDirectory
+import org.gradle.api.tasks.Optional
+
+import java.nio.file.Files
+import java.nio.file.Path
+import java.util.regex.Pattern
+
+@CompileStatic
+abstract class CheckPatches extends CheckTask {
+
+    private static final Pattern HUNK_START_PATTERN = Pattern.compile('^@@ -[0-9,]* \\+[0-9,_]* @@$')
+    private static final Pattern WHITESPACE_PATTERN = Pattern.compile('^[+\\-]\\s*$')
+    private static final Pattern IMPORT_PATTERN = Pattern.compile('^[+\\-]\\s*import.*')
+    private static final Pattern FIELD_PATTERN = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final)?([^=;]*)(=.*)?;\\s*$')
+    private static final Pattern METHOD_PATTERN = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final)?([^(]*)[(]([^)]*)?[)]\\s*[{]\\s*$')
+    private static final Pattern CLASS_PATTERN = Pattern.compile('^[+\\-][\\s]*((public|protected|private)[\\s]*)?(static[\\s]*)?(final[\\s]*)?(class|interface)([^{]*)[{]\\s*$')
+    private static final Map<String, Integer> ACCESS_MAP = [private: 0, protected: 2, public: 3].tap { it.put(null, 1) }
+
+    @InputDirectory abstract DirectoryProperty getPatchDir()
+    @Input @Optional abstract ListProperty<String> getPatchesWithS2SArtifact()
+
+    @Override
+    void check(Reporter reporter, boolean fix) {
+        final patchDir = getPatchDir().get().asFile.toPath()
+        Files.walk(patchDir).withCloseable {
+            it.filter(Files.&isRegularFile).forEach { path ->
+                final String relativeName = patchDir.relativize(path).toString()
+                verifyPatch(path, reporter, fix, relativeName, patchesWithS2SArtifact.get().contains(relativeName.replace('\\', '/')))
+            }
+        }
+    }
+    
+    static boolean accessChange(String previous, String current) {
+        //return ACCESS_MAP[previous] < ACCESS_MAP[current]
+        return previous != current
+    }
+
+    void verifyPatch(Path patch, Reporter reporter, boolean fix, String patchPath, boolean hasS2SArtifact) {
+        int oldFixedErrors = reporter.fixed.size()
+
+        final lines = Files.readAllLines(patch)
+
+        int hunksStart = 0
+        boolean onlyWhiteSpace = false
+
+        final List<String> newLines = []
+
+        // First two lines are file name ++/-- and we do not care
+        newLines.add(lines[0] + '\n')
+        newLines.add(lines[1] + '\n')
+
+        int i
+        for (i = 2; i < lines.size(); ++i) {
+            def line = lines[i]
+            newLines.add(line + '\n')
+
+            if (HUNK_START_PATTERN.matcher(line).find()) {
+                if (onlyWhiteSpace) {
+                    if (!hasS2SArtifact)
+                        reporter.report("Patch contains only white space hunk starting at line ${hunksStart + 1}, file: $patchPath")
+                    int toRemove = i - hunksStart
+                    while (toRemove-- > 0)
+                        newLines.remove(newLines.size() - 1)
+                }
+                hunksStart = i
+                onlyWhiteSpace = true
+                continue
+            }
+
+            if (line.startsWithAny('+','-')) {
+                def prefixChange = false
+                def prevLine = lines[i - 1]
+
+                if (line.charAt(0) == (char)'+' && prevLine.charAt(0) == (char)'-') {
+                    def prevTrim = prevLine.substring(1).replaceAll("\\s", "")
+                    def currTrim = line.substring(1).replaceAll("\\s", "")
+
+                    if (prevTrim == currTrim) {
+                        prefixChange = true
+                    }
+
+                    def pMatcher = FIELD_PATTERN.matcher(prevLine)
+                    def cMatcher = FIELD_PATTERN.matcher(line)
+
+                    if (pMatcher.find() && cMatcher.find() &&
+                            pMatcher.group(6) == cMatcher.group(6) && // = ...
+                            pMatcher.group(5) == cMatcher.group(5) && // field name
+                            pMatcher.group(3) == cMatcher.group(3) && // static
+                            (accessChange(pMatcher.group(2), cMatcher.group(2)) || pMatcher.group(4) != cMatcher.group(4))) {
+                        reporter.report("Patch contains access changes or final removal at line ${i + 1}, file: $patchPath", false)
+                    }
+
+                    pMatcher = METHOD_PATTERN.matcher(prevLine)
+                    cMatcher = METHOD_PATTERN.matcher(line)
+
+                    if (pMatcher.find() && cMatcher.find() &&
+                            pMatcher.group(6) == cMatcher.group(6) && // params
+                            pMatcher.group(5) == cMatcher.group(5) && // <T> void name
+                            pMatcher.group(3) == cMatcher.group(3) && // static
+                            (accessChange(pMatcher.group(2), cMatcher.group(2)) || pMatcher.group(4) != cMatcher.group(4))) {
+                        reporter.report("Patch contains access changes or final removal at line ${i + 1}, file: $patchPath", false)
+                    }
+
+                    pMatcher = CLASS_PATTERN.matcher(prevLine)
+                    cMatcher = CLASS_PATTERN.matcher(line)
+
+                    if (pMatcher.find() && cMatcher.find() &&
+                            pMatcher.group(6) == cMatcher.group(6) && // ClassName<> extends ...
+                            pMatcher.group(5) == cMatcher.group(5) && // class | interface
+                            pMatcher.group(3) == cMatcher.group(3) && // static
+                            (accessChange(pMatcher.group(2), cMatcher.group(2)) || pMatcher.group(4) != cMatcher.group(4))) {
+                        reporter.report("Patch contains access changes or final removal at line ${i + 1}, file: $patchPath", false)
+                    }
+                }
+
+                if (line.charAt(0) == (char)'-' && i + 1 < lines.size()) {
+                    final nextLine = lines[i + 1]
+                    if (nextLine.charAt(0) == (char)'+') {
+                        final nextTrim = nextLine.substring(1).replaceAll("\\s", "")
+                        final currTrim = line.substring(1).replaceAll("\\s", "")
+
+                        if (nextTrim == currTrim) {
+                            prefixChange = true
+                        }
+                    }
+                }
+
+                final isWhiteSpaceChange = WHITESPACE_PATTERN.matcher(line).find()
+
+                if (!prefixChange && !isWhiteSpaceChange) {
+                    onlyWhiteSpace = hasS2SArtifact && IMPORT_PATTERN.matcher(line).find()
+                } else if (isWhiteSpaceChange) {
+                    final prevLineChange = prevLine.startsWithAny('+','-')
+                    final nextLineChange = i + 1 < lines.size() && lines[i + 1].startsWithAny('+','-')
+
+                    if (!prevLineChange && !nextLineChange) {
+                        reporter.report("Patch contains white space change in valid hunk at line ${i + 1}, file: $patchPath \n$prevLine\n$line\n${lines[i+1]}", false)
+                    }
+                }
+
+                if (line.contains('\t')) {
+                    reporter.report("Patch contains tabs on line ${i + 1}, file: $patchPath")
+                    line = line.replaceAll('\t', '    ')
+                    newLines.remove(newLines.size() - 1)
+                    newLines.add(line + '\n')
+                }
+
+                if (IMPORT_PATTERN.matcher(line).find() && !hasS2SArtifact) {
+                    reporter.report("Patch contains import change on line ${i + 1}, file: $patchPath", false)
+                }
+            }
+        }
+
+        if (onlyWhiteSpace) {
+            if (!hasS2SArtifact)
+                reporter.report("Patch contains only white space hunk starting at line ${hunksStart + 1}, file: $patchPath")
+            def toRemove = i - hunksStart;
+            while (toRemove-- > 0)
+                newLines.remove(newLines.size() - 1)
+        }
+
+        if ((reporter.fixed.size() > oldFixedErrors && fix) || hasS2SArtifact) {
+            if (newLines.size() <= 2) {
+                logger.lifecycle("Patch is now empty removing, file: {}", patchPath)
+                Files.delete(patch)
+            }
+            else {
+                if (!hasS2SArtifact)
+                    logger.lifecycle("*** Updating patch file. Please run setup then genPatches again. ***")
+                Files.newBufferedWriter(patch).withCloseable {
+                    newLines.each { l -> it.write(l) }
+                }
+            }
+        }
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckSAS.groovy

@@ -0,0 +1,110 @@
+package net.minecraftforge.forge.tasks.checks
+
+import groovy.transform.CompileStatic
+import net.minecraftforge.forge.tasks.Annotatable
+import net.minecraftforge.forge.tasks.InheritanceData
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.InputFiles
+
+@CompileStatic
+abstract class CheckSAS extends CheckTask {
+
+    @InputFile abstract RegularFileProperty getInheritance()
+    @InputFiles abstract ConfigurableFileCollection getSass()
+
+    @Override
+    void check(Reporter reporter, boolean fix) {
+        final inheritance = InheritanceData.parse(this.inheritance.get().asFile)
+
+        sass.each { f ->
+            final lines = []
+            f.eachLine { line ->
+                if (line[0] == '\t') return // Skip any tabbed lines, those are ones we add
+                final idx = line.indexOf('#')
+                if (idx == 0 || line.isEmpty()) {
+                    lines.add(line)
+                    return
+                }
+                def comment = idx == -1 ? null : line.substring(idx)
+                if (idx != -1) line = line.substring(0, idx - 1)
+                final spl = (line.trim().replace('(', ' (') + '     ').split(' ', -1)
+                def (String cls, String name, String desc) = [spl[0], spl[1], spl[2]]
+                cls = cls.replaceAll('\\.', '/')
+
+                if (inheritance[cls] === null) {
+                    reporter.report("Invalid: $line")
+                } else if (name.isEmpty()) { //Class SAS
+                    final toAdd = []
+                    final clsSided = isSided(inheritance[cls])
+                    boolean sided = clsSided
+
+                    /* TODO: MergeTool doesn't do fields
+                    if (json[cls]['fields'] != null) {
+                        for (entry in json[cls]['fields']) {
+                            if (isSided(entry.value)) {
+                                sided = true
+                                toAdd.add('\t' + cls + ' ' + entry.key)
+                            }
+						}
+                    } */
+
+                    final clsInh = inheritance[cls]
+                    if (clsInh.methods) {
+                        for (entry in clsInh.methods) {
+                            if (isSided(entry.value)) {
+                                sided = true
+                                toAdd.add('\t' + cls + ' ' + entry.key.replaceAll(' ', ''))
+                                findChildMethods(inheritance, cls, entry.key).each { lines.add('\t' + it) }
+                                findChildMethods(inheritance, cls, entry.key).each { println(line + ' -- ' + it) }
+                            } else if (clsSided) {
+                                findChildMethods(inheritance, cls, entry.key).each { lines.add('\t' + it) }
+                                findChildMethods(inheritance, cls, entry.key).each { println(line + ' -- ' + it) }
+                            }
+                        }
+                    }
+
+                    if (sided) {
+                        lines.add(cls + (comment == null ? '' : ' ' + comment))
+                        lines.addAll(toAdd.sort())
+                    } else {
+                        reporter.report("Invalid: $line")
+                    }
+
+                } else if (desc.isEmpty()) { // Fields
+                    /* TODO: MergeTool doesn't do fields
+                    if (json[cls]['fields'] != null && isSided(json[cls]['fields'][name]))
+                        lines.add(cls + ' ' + name + (comment == null ? '' : ' ' + comment))
+                    else */
+                    reporter.report("Invalid: $line")
+                } else { // Methods
+                    final clsInh = inheritance[cls]
+                    if (clsInh.methods === null || !isSided(clsInh.methods[name + ' ' + desc]))
+                        reporter.report("Invalid: $line")
+                    else {
+                        lines.add(cls + ' ' + name + desc + (comment == null ? '' : ' ' + comment))
+                        findChildMethods(inheritance, cls, name + ' ' + desc).each { println(line + ' -- ' + it) }
+                        findChildMethods(inheritance, cls, name + ' ' + desc).each { lines.add('\t' + it) }
+                    }
+                }
+            }
+
+            if (fix) f.text = lines.join('\n')
+        }
+    }
+
+    protected static boolean isSided(Annotatable annotatable) {
+        if (annotatable === null) return false
+        for (ann in annotatable.annotations) {
+            if ('Lnet/minecraftforge/api/distmarker/OnlyIn;' == ann.desc)
+                return true
+        }
+        return false
+    }
+    
+    protected static findChildMethods(Map<String, InheritanceData> json, String cls, String desc) {
+        return json.values().findAll{ it.methods !== null && it.methods[desc] !== null && it.methods[desc].override == cls && isSided(it.methods[desc]) }
+                .collect { it.name + ' ' + desc.replace(' ', '') } as TreeSet
+    }
+}

buildSrc/src/main/groovy/net/minecraftforge/forge/tasks/checks/CheckTask.groovy

@@ -0,0 +1,114 @@
+package net.minecraftforge.forge.tasks.checks
+
+import groovy.transform.CompileStatic
+import groovy.transform.stc.ClosureParams
+import groovy.transform.stc.ThirdParam
+import net.minecraftforge.forge.tasks.Util
+import org.gradle.api.Action
+import org.gradle.api.DefaultTask
+import org.gradle.api.logging.LogLevel
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.TaskAction
+import org.gradle.api.tasks.TaskContainer
+import org.gradle.api.tasks.VerificationTask
+
+@CompileStatic
+abstract class CheckTask extends DefaultTask implements VerificationTask {
+    @Input
+    abstract Property<CheckMode> getMode()
+
+    private boolean ignoreFailures = false
+
+    @Input
+    @Override
+    boolean getIgnoreFailures() {
+        return ignoreFailures
+    }
+
+    @Override
+    void setIgnoreFailures(boolean ignoreFailures) {
+        this.ignoreFailures = ignoreFailures
+    }
+
+    @TaskAction
+    void run() {
+        Util.init()
+
+        boolean doFix = getMode().get() === CheckMode.FIX
+        final Reporter reporter = new Reporter(doFix)
+        check(reporter, doFix)
+
+        if (reporter.messages) {
+            if (getMode().get() === CheckMode.CHECK) {
+                logger.error("Check task '{}' found errors:\n{}", name, reporter.messages.join('\n'))
+                if (!ignoreFailures) {
+                    throw new IllegalArgumentException("${reporter.messages.size()} errors were found!")
+                }
+            } else {
+                if (logger.isEnabled(LogLevel.DEBUG)) {
+                    logger.warn("Check task '{}' found {} errors and fixed {}:\n{}", name, reporter.messages.size(), reporter.fixed.size(), reporter.fixed.join('\n'))
+                } else {
+                    logger.warn("Check task '{}' found {} errors and fixed {}.", name, reporter.messages.size(), reporter.fixed.size())
+                }
+
+                if (reporter.notFixed) {
+                    logger.error('{} errors could not be fixed:\n{}', reporter.notFixed.size(), reporter.notFixed.join('\n'))
+                    if (!ignoreFailures) {
+                        throw new IllegalArgumentException("${reporter.notFixed.size()} errors which cannot be fixed were found!")
+                    }
+                }
+            }
+        }
+    }
+
+    abstract void check(Reporter reporter, boolean fix)
+
+    @CompileStatic
+    static final class Reporter {
+        final boolean trackFixed
+        Reporter(boolean trackFixed) {
+            this.trackFixed = trackFixed
+        }
+
+        public final List<String> messages = []
+
+        public final List<String> fixed = []
+        public final List<String> notFixed = []
+
+        void report(String message, boolean canBeFixed = true) {
+            messages.add(message)
+
+            if (trackFixed) {
+                if (canBeFixed) {
+                    fixed.add(message)
+                } else {
+                    notFixed.add(message)
+                }
+            }
+        }
+    }
+
+    static <T extends CheckTask> void registerTask(TaskContainer tasks, String taskName, @DelegatesTo.Target('type') Class<T> clazz,
+                                                   @DelegatesTo(genericTypeIndex = 0, target = 'type')
+                                                   @ClosureParams(ThirdParam.FirstGenericType) Closure configuration) {
+        taskName = taskName.capitalize()
+        tasks.register("check$taskName", clazz) { CheckTask task ->
+            def castedTask = task as T
+            configuration.setDelegate(castedTask)
+            configuration.call(castedTask)
+            castedTask.mode.set(CheckMode.CHECK)
+            castedTask.group = 'checks'
+        }
+        tasks.named('checkAll').configure { it.dependsOn("check$taskName") }
+
+        tasks.register("checkAndFix$taskName", clazz) { CheckTask task ->
+            def castedTask = task as T
+            configuration.setDelegate(castedTask)
+            configuration.call(castedTask)
+            castedTask.mode.set(CheckMode.FIX)
+            castedTask.group = 'checks'
+        }
+        tasks.named('checkAllAndFix').configure { it.dependsOn("checkAndFix$taskName") }
+    }
+}

build_clean.gradle

@@ -0,0 +1,73 @@
+plugins {
+    id 'java-library'
+    id 'net.minecraftforge.gradle.patcher'
+}
+
+evaluationDependsOn(':mcp')
+
+repositories {
+    mavenCentral()
+    maven gradleutils.forgeMaven
+    maven gradleutils.minecraftLibsMaven
+}
+    
+java.toolchain.languageVersion = JavaLanguageVersion.of(JAVA_VERSION)
+
+dependencies {
+	implementation(libs.forgespi)
+}
+
+patcher {
+	parent = project(':mcp')
+	mcVersion = MC_VERSION
+	patchedSrc = file('src/main/java')
+
+	mappings channel: MAPPING_CHANNEL, version: MAPPING_VERSION
+
+	runs {
+		clean_client {
+			client true
+			taskName 'clean_client'
+			ideaModule "${rootProject.name}.${project.name}.main"
+
+			main 'net.minecraft.client.main.Main'
+			workingDirectory project.file('run/client')
+
+			args '--gameDir', '.'
+			args '--version', MC_VERSION
+			args '--assetsDir', downloadAssets.output
+			args '--assetIndex', '{asset_index}'
+			args '--accessToken', '0'
+		}
+
+		clean_server {
+			client false
+			taskName 'clean_server'
+			ideaModule "${rootProject.name}.${project.name}.main"
+
+			main 'net.minecraft.server.Main'
+			workingDirectory project.file('run/server')
+		}
+	}
+}
+
+tasks.withType(JavaCompile).configureEach {
+    options.encoding = 'UTF-8' // Use the UTF-8 charset for Java compilation
+    options.warnings = false // Shutup deprecated for removal warnings
+}
+
+eclipse.classpath.file.whenMerged {
+	// Disable optional warnings on the minecraft decompiled source code. It just muddies the warning window and hides warnings in our own codebase
+	def src = entries.find { it.path == 'src/main/java' }
+    if (src == null) throw new IllegalStateException("You must run `setup` task before importing")
+    src.entryAttributes['ignore_optional_problems'] = 'true'
+}
+
+tasks.named('genPatches').configure {
+    onlyIf { false }
+}
+
+tasks.named('extractRangeMap').configure {
+    onlyIf { false }
+    tool = 'net.minecraftforge:Srg2Source:8.1.0:fatjar'
+}

build_shared.gradle

@@ -0,0 +1,89 @@
+import net.minecraftforge.forge.tasks.CleanProperties
+
+apply plugin: 'eclipse'
+apply plugin: 'idea'
+apply plugin: 'net.minecraftforge.gradleutils'
+
+group = 'net.minecraftforge'
+version = VERSION
+println("Version: $version")
+
+repositories {
+    mavenCentral()
+    maven gradleutils.forgeMaven
+    maven gradleutils.minecraftLibsMaven
+    //mavenLocal()
+}
+
+tasks.withType(Javadoc).configureEach {
+    options.tags = [
+        'apiNote:a:<em>API Note:</em>',
+        'implSpec:a:<em>Implementation Requirements:</em>',
+        'implNote:a:<em>Implementation Note:</em>'
+    ]
+    options.addStringOption('Xdoclint:all,-missing', '-public')
+}
+
+// We need to write the manifest to the binary file so we have properly versioned packaged at dev time.
+tasks.register('writeManifest') {
+    doLast {
+        if (plugins.findPlugin('net.minecraftforge.gradle.patcher')) // Forge project
+            universalJar.manifest.writeTo(rootProject.file('src/main/resources/META-INF/MANIFEST.MF'))
+        else
+            jar.manifest.writeTo(project.file('src/main/resources/META-INF/MANIFEST.MF'))
+    }
+}
+
+tasks.register('generateResources') {
+    dependsOn('writeManifest')
+}
+
+tasks.named('processResources') {
+    dependsOn(generateResources)
+}
+
+// Make sure out manifests get written before compiling the code, IDEA calls this task if you tell it to use the gradle build.
+tasks.withType(JavaCompile).configureEach {
+    dependsOn 'generateResources'
+    dependsOn 'processResources' // Needed because we merge the output of this with the output of the compile task. And gradle detects downstream tasks using the output without a hard dep
+    options.encoding = 'UTF-8' // Use the UTF-8 charset for Java compilation
+    options.warnings = false // Shutup deprecated for removal warnings
+    options.forkOptions.jvmArgs += '-Xmx6G' // Needed to make compiling faster, and not run out of heap space in some cases.
+}
+
+// Merge the resources and classes into the same directory. We'll need to split them at runtime because
+// Minecraft and Forge are in the same sourceSet as they are inter dependent.. for now..
+sourceSets.each {
+    def dir = layout.buildDirectory.dir("classes/java/$it.name")
+    it.output.resourcesDir = dir
+    it.java.destinationDirectory = dir
+}
+
+tasks.register('copyEclipseSettings') {
+    doLast {
+        rootProject.fileTree('ide/eclipse/template/.settings/').matching { include '**/*.prefs' }.each { file ->
+            def target = project.file('.settings/' + file.name)
+            def temp = new CleanProperties().load(file)
+            def exst = new CleanProperties().load(target)
+            exst.put('eclipse.preferences.version', '1')
+            exst.putAll(temp)
+            exst.store(target)
+        }
+    }
+}
+
+// TODO: [Gradle][IntelliJ] Auto trigger these tasks on import.
+eclipse {
+    // Run everytime eclipse builds the code
+    //autoBuildTasks writeManifest
+    // Run when importing the project
+    synchronizationTasks generateResources, copyEclipseSettings, eclipseClasspath, eclipseProject
+}
+
+idea {
+    module {
+        // IntelliJ IDEA does not do this by itself anymore...
+        downloadJavadoc = true
+        downloadSources = true
+    }
+}

docs/CONTRIBUTING.md

@@ -1,13 +1,13 @@
 Contributing to Forge
 =====================
 
-1) Keep patches to Minecraft classes minimal. If you need a lot of things done, you may either add to relevant forge classes or make a new class.
+1) Keep patches to Minecraft classes together. If you need a lot of things done, you may either add to relevant forge classes or make a new class. Try not to spread out your patches across multiple disjoint lines, as this makes maintenance of your patches difficult.
 
-2) An example mod must be provided for all PRs adding events/hooks to Forge. Whether it's a full mod using your proposed hooks, or just a pastebin containing a simple example, an example mod is required. Please also explain in detail what your new hook does.
+2) TODO: Test Mods
 
-3) Follow Forge coding guidelines (braces on newlines, spaces instead of tabs, etc)
+3) Follow the code style of the class you're working in (braces on newlines & spaces instead of tabs in Forge classes, inline brackets in patches, etc).
 
-For more information, refer to [the wiki](https://github.com/MinecraftForge/MinecraftForge/wiki/If-you-want-to-contribute-to-Forge)
+For more information, refer to [the wiki][Wiki].
 
 
 Contributor License Agreement
@@ -16,3 +16,5 @@ Contributor License Agreement
 - You assign copyright ownership of your contributions to the patches codebase (everything under patches) to Forge, where it will be licensed under the LGPLv2.1 license.
 
 "Forge" is Forge Development LLC, a legally incorporated entity in Oregon, USA.
+
+[Wiki]: https://github.com/MinecraftForge/MinecraftForge/wiki/If-you-want-to-contribute-to-Forge

docs/EnergySystems.md

@@ -1,9 +0,0 @@
-# On the Contribution of an RF-lite Energy System: "Energy"
-Forge has acquired an Energy system, after many years of debate on the topic. The prevalence of the RF API has warranted the inclusion of a similar (but simpler) implementation to forge for 1.10.2 and onwards.
-Those who wish to use an RF like API, feel free to use it. If you don't want to think about Energy, but know you need it, you can use it *if you wish*. If you want to interoperate with other energy systems, feel free to use this to broker with them.
-
-# On Diversity in Energy Systems
-Forge has always supported diversity in energy-like systems. If you have a burning desire to simulate electricity flow in all it's glory, we fully support you and look forward to playing your mod. If you wish to have pneumatic power, we have no objections, and would love to see your wonderful creations. If you have a power system of your own devising that is simply beyond our imagination, please, blow us away.
-
-# On Modder Obligations
-As a modder, you are under *no* obligation to use or support the forge Energy system. If anyone, user, mod-pack maker or even us, tells you otherwise, refer them to this statement. The Forge energy system is not intended to supplant diversity in energy systems. It is not intended to be one-size-fits-all. The choice to support it, is the choice of the modder.

docs/NewFML.md

@@ -1,127 +0,0 @@
-# FML
-
-Entrypoint : ```FMLServiceProvider.onLoad```
-
-- Verify environment
--- Check all libraries are present: ```accesstransformer```, ```coremod```, ```deobfuscator```
--- Check versions are suitable: ```modlauncher```, ```accesstransformer```, ```coremod```, ```deobfuscator```
-- Find deobfuscated and patched MC
--- If not found, trigger job to generate that (loaded later at FMLLaunchProvider.launch)
-
-Injected arguments:
-
-- ```mods``` : CSV list of mod files to load
-- ```modlist``` : JSON formatted list of mod files in a maven-like repository format
-
-Entrypoint : ```FMLServiceProvider.initializer```
-- Setup paths
--- ```mods``` folder
--- ```config``` folder
-- FML config file read (JSON?)
-- Trigger initial loading
-
-Entrypoint : ```FMLLaunchProvider.launch```
-- Launches the patched and deobfuscated game
-- - If that wasn't found it'll be generated from the vanilla jar and patch/deobf files (see above)
-- Possible we'll use an alternative launch for the development environment
-
-(A goal is that we pre-generate this JAR during forge installation or modpack installation)
-
-## Loading
-
-- First we discover all mods
-- - IModLocator instances present in system are found and queried to compile a master list of all mod artifacts of the three types
-- LANGPROVIDERs are added to the supported language system : IModLanguageProvider
-- The MODS from the list have their META-INF/mods.json file queried for mod instances to load
-- - MODS are cross-referenced for their language being available
-- - MODS are cross-referenced for their libraries being available
-- - MODS are cross-referenced for their MOD dependencies being available
-- - MODS with META-INF/coremods.json specification are loaded into the COREMOD system
-- - MODS with META-INF/accesstransformer.json are loaded into the ACCESSTRANSFORMER system
-- - MODS are enqueued to the background loading system
-- FMLLaunchProvider will be triggered from the ModLauncher to start the game
-
-## Game loading
-
-- Events triggered from loadGame will launch various phases of modloading as before
--- Deprecation of old "FML" events in favour of Forge events
--- If a mod hasn't completed scanning there might be a pause waiting for it to complete before loading (testing indicates this should be a very rare occurrence and isn't worse than existing status quo where all scanning and loading is on-thread)
-
-### ```IModLocator```
-
-Finds mods from various sources of various types
-manifest is queried for type: FMLModType
-
-- MOD : this file will be scanned as a mod. This is default if nothing is present
-- LIBRARY : this file will be added to the classpath and no further processing is done
-- LANGPROVIDER : this file will be loaded as a language provider
-
-#### ```ModsFolderLocator```
-
-- scans for jar files from mods folder
--- able to load all types
--- loads in all environments
--- maybe able to do runtime name transformation for dev time?
-
-Standard mechanism to find and load mods
-
-#### ```ExplodedDirectoryLocator```
-
-- loads a directory as a mod
--- only able to load mods
--- should only load in dev env
-
-Intended as a mechanism to allow development of mods easily by pointing at a compiled output directory
-
-#### ```ArgumentModsLocator``` : NYI
-
-- loads mods from the arguments on the command line
--- able to load all types
--- loads in all environments
-
-### ```IModLanguageProvider```
-
-Provides mod and language provider services
-
-- Provides a means to transform a Mod File (from the IModLocator) into a list of modcontainer objects based on mods.json
-- Scanning work will be done in background threads
-- Language providers can be provided as JARs via the modlocator for ease of distribution
-
-#### ```FMLModLanguageProvider```
-
-This is the standard Java @Mod implementation provider
-
-- provided by default (always supported)
-- All scanning for @Mod will be done in the background thread
-
-#### ```ScalaModLanguageProvider```
-
-This is the scala language provider. It'll be provided separately as a JAR mod download.
-
-- API contract will need definition
-
-Other languages? Kotlin? Alternative Scala versions? Javascript?
-
-## Coremods
-
-Coremods are now forcefully separated into _injection_ and _runtime_ phases.
-
-### Injection
-
-Injection is the act of intercepting the loading of a class and modifying the inbound class with alterations such as additions, replacements and deletions
-
-Injections will be written using Javascript. Two functions are required: a function providing the list of injection sites, and the function to transform the injection site.
-
-All injection sites will need to be pre-specified by the coremod in their metadata. Lookup services should be provided in the Javascript API.
-
-Javascript API for common coremod injection tasks needs to be developed, to allow common best-practice tooling for these complex tasks.
-
-Runtime coremod code (code that has been injected) is Java as usual.
-
-## Background loading thread
-
-Early in loading, a background thread is triggered which will perform scanning tasks for common resources, such as @Mod instances and other annotations. This thread will also be responsible for loading any cached resources, either those defined at build time or pre-computed from previous runs. It may also be tasked with writing those precomputed resources.
-
-There will be a IPreLoaderJobProvider that will allow extension of the scope of these tasks
-
-

docs/README.md

@@ -2,28 +2,24 @@
 
 MinecraftForge
 =============
-[![Stable Release](https://img.shields.io/badge/dynamic/json?url=https://files.minecraftforge.net/net/minecraftforge/forge/promotions_slim.json&label=Stable&prefix=1.17.1-&query=$.promos["1.17.1-recommended"]&color=brightgreen&logo=data:image/svg+xml;base64,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)](https://files.minecraftforge.net)
-[![Latest Release](https://img.shields.io/badge/dynamic/json?url=https://files.minecraftforge.net/net/minecraftforge/forge/promotions_slim.json&label=Latest&prefix=1.17.1-&query=$.promos["1.17.1-latest"]&color=blue&logo=data:image/svg+xml;base64,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
-)](https://files.minecraftforge.net) [![Discord](https://img.shields.io/discord/313125603924639766.svg?color=%237289da&label=Discord&logo=discord&logoColor=%237289da)](https://discord.gg/UvedJ9m) [![Support](https://img.shields.io/badge/Patreon-Support-orange.svg?logo=Patreon)](https://www.patreon.com/LexManos)
+[![Stable Release](https://img.shields.io/badge/dynamic/json?url=https://files.minecraftforge.net/net/minecraftforge/forge/promotions_slim.json&label=Stable&prefix=1.21.11-&query=$.promos["1.21.11-recommended"]&color=brightgreen&logo=data:image/svg+xml;base64,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)][Download]
+[![Latest Release](https://img.shields.io/badge/dynamic/json?url=https://files.minecraftforge.net/net/minecraftforge/forge/promotions_slim.json&label=Latest&prefix=26.1.2-&query=$.promos["26.1.2-latest"]&color=blue&logo=data:image/svg+xml;base64,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
+)][Download] [![Discord](https://img.shields.io/discord/313125603924639766.svg?color=%237289da&label=Discord&logo=discord&logoColor=%237289da)][Discord] [![Support](https://img.shields.io/badge/Patreon-Support-orange.svg?logo=Patreon)][Patreon]
 
 Forge is a free, open-source modding API all of your favourite mods use!
 
-|    Version    |    Support    |
-| ------------- | ------------- |
-|    1.17.x     |    Active     |
-|    1.16.x     |    LTS        |
+| Version      | Support                     |
+|--------------|-----------------------------|
+| All versions | [Supported][Support-Policy] |
 
 * [Download]
 * [Forum]
 * [Discord]
 * [Documentation]
 
-#### Notes:
-- Introduced in 1.13 was a new FML, information found [here](NewFML.md).
-
 # Installing Forge
 
-Go to [the Forge website](https://files.minecraftforge.net)
+Go to [the Forge website][Download]
  and select the Minecraft version you wish to get Forge for from the list.
 
 You can download the installer for the *Recommended Build* or the
@@ -32,37 +28,76 @@ You can download the installer for the *Recommended Build* or the
  into your vanilla launcher environment, where you can then create a new
  profile using that version and play the game!
  
-For support and questions, visit [the Support Forum](https://www.minecraftforge.net/forum/forum/18-support-bug-reports/).
+For support and questions, visit [the Support Forum][Support-Forum] or [the Forge Discord server][Discord].
 
-[Here is a short video from Rorax showing how to install and setup Forge.](https://www.youtube.com/watch?v=lB3ArN_-3Oc)
+## Required Java Versions
+
+We require the version of Java that Minecraft requires, which is currently:
+
+| Minecraft        | Java              |
+|------------------|-------------------|
+| 26.1+            | [25][Adoptium-25] |
+| 1.20.6 - 1.21.11 | [21][Adoptium-21] |
+| 1.18 - 1.20.4    | [17][Adoptium-17] |
+| 1.17.1           | [16][Adoptium-16] |
+| 1.16.5-          | [8][Adoptium-8]   |
+
+**If you are on Windows and have difficulty using Java to launch JAR files, consider using [Jarfix by Johann Löfflmann][Jarfix].**
 
 # Creating Mods
 
-[See the "Getting Started" section in the Forge Documentation](https://mcforge.readthedocs.io/en/latest/gettingstarted/).
+[See the "Getting Started" section in the Forge Documentation][Getting-Started].
 
 # Contribute to Forge
 
 If you wish to actually inspect Forge, submit PRs or otherwise work
  with Forge itself, you're in the right place!
- 
- [See the guide to setting up a Forge workspace](http://mcforge.readthedocs.io/en/latest/forgedev/).
+
+ [See the guide to setting up a Forge workspace][ForgeDev].
 
 ### Pull requests
 
-[See the "Making Changes and Pull Requests" section in the Forge documentation](https://mcforge.readthedocs.io/en/latest/forgedev/#making-changes-and-pull-requests).
+[See the "Making Changes and Pull Requests" section in the Forge documentation][Pull-Requests].
 
-Please read the contributing guidelines found [here](CONTRIBUTING.md) before making a pull request.
+Please read the contributing guidelines found [here][Contributing] before making a pull request.
 
 ### Contributor License Agreement
-We require all contributors to acknowledge the [Forge Contributor
- License Agreement](https://cla-assistant.io/MinecraftForge/MinecraftForge). Please ensure you have a valid email address
- associated with your GitHub account to do this. If you have previously
+We require all contributors to acknowledge the [Forge Contributor License Agreement][CLA]. 
+Please ensure you have a valid email address associated with your GitHub account to do this. If you have previously 
  signed it, you should be OK.
 
 #### Donate
-*Forge is a large project with many collaborators working on it around the clock. Forge is and will always remain free to use and modify. However, it costs money to run such a large project as this, so please consider [becoming a patron](https://www.patreon.com/LexManos).*
+*Forge is a large project with many collaborators working on it around the clock. Forge is and will always remain free 
+ to use and modify. However, it costs money to run such a large project as this, so please consider 
+ [becoming a patron][Patreon].*
+
+### Thanks
+[![YourKit](https://www.yourkit.com/images/yklogo.png)](https://www.yourkit.com/)
+
+YourKit for providing us accesss to their [YourKit Java Profiler] which helps identify bottlenecks and places for improvment.
+
+[Contributing]: ./CONTRIBUTING.md
+[CLA]: https://cla-assistant.io/MinecraftForge/MinecraftForge
 
 [Download]: https://files.minecraftforge.net/
-[Forum]: https://www.minecraftforge.net/forum/
-[Discord]: https://discord.gg/UvedJ9m
-[Documentation]: https://mcforge.readthedocs.io
+
+[Adoptium-25]: https://adoptium.net/temurin/releases/?version=25
+[Adoptium-21]: https://adoptium.net/temurin/releases/?version=21
+[Adoptium-17]: https://adoptium.net/temurin/releases/?version=17
+[Adoptium-16]: https://adoptium.net/temurin/releases/?version=16
+[Adoptium-8]: https://adoptium.net/temurin/releases/?version=8
+[Jarfix]: https://johann.loefflmann.net/en/software/jarfix/index.html
+
+[Forum]: https://forums.minecraftforge.net/
+[Support-Forum]: https://forums.minecraftforge.net/forum/18-support-bug-reports/
+[Support-Policy]: https://forums.minecraftforge.net/topic/144690-new-tiered-support-policy
+
+[Discord]: https://discord.minecraftforge.net/
+
+[Documentation]: https://docs.minecraftforge.net/
+[Getting-Started]: https://docs.minecraftforge.net/en/latest/gettingstarted/
+[ForgeDev]: https://docs.minecraftforge.net/en/latest/forgedev/
+[Pull-Requests]: https://docs.minecraftforge.net/en/latest/forgedev/#making-changes-and-pull-requests
+
+[Patreon]: https://www.patreon.com/LexManos
+[YourKit Java Profiler]: https://www.yourkit.com/java/profiler/

docs/SUPPORT.md

@@ -1,7 +1,7 @@
 Getting Support Surrounding Forge
 =================================
 
-**If you do not want to read the following wall of text, no matter its relevance for helping get your issue resolved quickly, please refer to the [Forge Forums](http://www.minecraftforge.net/forum/forum/18-support-bug-reports/) for support.**
+**If you do not want to read the following wall of text, no matter its relevance for helping get your issue resolved quickly, please refer to the [Forge Forums][Bug-Reports] for support.**
 
 Before reporting an issue on this repository's bug tracker, please carefully read this document. There are various resources that are more likely to be able to help you with certain kinds of issues. This document provides instructions on how to determine which place best to report to.
 
@@ -44,7 +44,7 @@ You can generally tell pretty quickly what caused the error at the head of your
  1. If you can find the name of a mod in the trace, that mod most likely is the culprit.
     - Be aware that you may find multiple mods as participants of a crash. In that case, you can either report to both or try to reason (using the names in the stacktrace) about which mod is at fault.
  2. If you can only find Forge (usually starting with `net.minecraftforge`) alongside Vanilla (usually starting with `net.minecraft`) references, chances are that you have found a bug in Forge. In this case, use one of the various [support channels](#forge-support) listed below.
-    - The occurence of a single call to Forge somewhere in the stacktrace *does not* warrant a report to Forge if there are mods present in the crash report.
+    - The occurrence of a single call to Forge somewhere in the stacktrace *does not* warrant a report to Forge if there are mods present in the crash report.
  3. If there's no mention of Forge or a mod, but any Vanilla class, you might have found a Vanilla bug. You should probably still report it via the Forge channels first, however, due the nature of modded environments and the rarity of Vanilla crash bugs.
  4. Always check whether there's a mention of coremods at the beginning of a crash report. If there is and you can't find any clear culprit, consider reporting to these coremods first, since they are free to change any of the code executed in your environment.
 
@@ -74,17 +74,18 @@ Please note that this list has to be considered incomplete as there is a large n
 
 If you're certain you've found an issue that is directly caused by Forge, you have the following three platforms available for dealing with it, with decreasing relevance for end-users:
 
- 1. **Forge Forums:** There's a dedicated [Support & Bug Report](http://www.minecraftforge.net/forum/forum/18-support-bug-reports/) section on the Forge forums, which is led by team of moderators and volunteers who will try to deal with your reports as quickly as possible. *As a player you should probably report here first.*
-   - For modders, there also is a separate [Modder Support](http://www.minecraftforge.net/forum/forum/70-modder-support/) section where you can ask all your development-related questions. *You should prefer this section for coding help.*
- 2. **Forge IRC Channel:** You can find a lot of help on the official [`#minecraftforge`](irc://irc.esper.net:6667/minecraftforge) channel on EsperNet. Especially smaller issues that you quickly need help with could be reported there. *Be aware that the channel is more suited towards development questions, so while you may get support there as a player, you should almost always prefer the forums.*
- 3. **Forge Issue Tracker:** If you're absolutely certain that you've found an issue in the Forge codebase (e.g. you're a modder yourself and have analyzed the stacktrace and relevant code), don't refrain from reporting it on this repository's [issue tracker](https://github.com/MinecraftForge/MinecraftForge/issues). *Please do not use the issues as a means of getting coding help. For developers, the IRC and the [official documentation](https://mcforge.readthedocs.io) are the best sources of information.*
+ 1. **Forge Forums:** There's a dedicated [Support & Bug Report][Bug-Reports] section on the Forge forums, which is led by team of moderators and volunteers who will try to deal with your reports as quickly as possible. *As a player you should probably report here first.*
+   - For modders, there also is a separate [Modder Support][Modder-Support] section where you can ask all your development-related questions. *You should prefer this section for coding help.*
+ 2. **Forge Discord Server:** You can find a lot of help on the official [Discord Server][Discord], especially smaller issues that you quickly need help with. *Be aware that the channel is more suited towards development questions, so while you may get support there as a player, you should almost always prefer the forums.*
+ 3. **Forge Issue Tracker:** If you're absolutely certain that you've found an issue in the Forge codebase (e.g. you're a modder yourself and have analyzed the stacktrace and relevant code), don't refrain from reporting it on this repository's [issue tracker](https://github.com/MinecraftForge/MinecraftForge/issues). *Please do not use the issues as a means of getting coding help. For developers, the IRC and the [official documentation][Documentation] are the best sources of information.*
 
 ### Mod Support
 
 A lot of mods also use GitHub or other source management systems and their integrated issue trackers. The following options will give you the best chances of reporting your issue in the right place:
 
  - **CurseForge:** Many mods are hosted on the [CurseForge platform](https://minecraft.curseforge.com) nowadays. Chances are you already downloaded them from there or as a part of a modpack hosted there. Projects may specify an issue reporting link on their own page, so simply look for it on the mod's project page and you should be directed to the preferred means of error reporting.
- - **Searching for a repository directly:** You may need to try and find a repository directly on source control sites. The most common ones are [GitHub](https://github.com) and [BitBucket](https://bitbucket.org). Both come with search capabilities, so simply try to search for the mod's name.
+ - **Modrinth:** Some modders use [Modrinth](https://modrinth.com/mods) to host their mods, but be mindful that not all mods on this platform are for the Forge modloader.
+ - **Searching for a repository directly:** You may need to try and find a repository directly on source control sites. The most common ones are [GitHub](https://github.com), [GitLab](https://gitlab.com), and [BitBucket](https://bitbucket.org). Both come with search capabilities, so simply try to search for the mod's name.
 
 ### Vanilla Support
 
@@ -98,7 +99,7 @@ Now that you've identified the source of your issue and decided on the correct s
 ### Preventing Duplicates and Unnecessary Reports
 Use the target issue tracker's search functionality to look for issues which have descriptions similar to yours, but make sure to also search for already closed issues. If you can find one, verify it is in fact the same (or a very similar issue) and simply comment on it if you have anything else to contribute to the discussion, such as other steps to reproduce it. *Do not create duplicates of an existing issue, since it only puts extra effort on maintainers to recognize and close/mark them.*
 
-Additionally, always check the *latest* changelogs of Forge and participating mods to find out if the bug was already noticed and fixed by the developer. Often the maintainer may only support newer versions of the game, so also check the changelogs for versions of Minecraft you don't actually actively play. If the issue was adressed already, *do not report it*, even if the fix only exists for a newer version of the game, since the developer probably had a good reason to do so. If your issue only exists with versions of a mod that are for very old versions of the game, also refrain from reporting them, considering most modders only support the two latest versions of Minecraft, if at all.
+Additionally, always check the *latest* changelogs of Forge and participating mods to find out if the bug was already noticed and fixed by the developer. Often the maintainer may only support newer versions of the game, so also check the changelogs for versions of Minecraft you don't actually actively play. If the issue was addressed already, *do not report it*, even if the fix only exists for a newer version of the game, since the developer probably had a good reason to do so. If your issue only exists with versions of a mod that are for very old versions of the game, also refrain from reporting them, considering most modders only support the two latest versions of Minecraft, if at all.
 
 ### Required Information
 If you're certain that your issue went unnoticed up until now, you can get to actually writing up the report. Below you can find a list of the *required* information any bug report should contain:
@@ -143,4 +144,11 @@ After you have written your bug report, it is time to *wait*. Please be *patient
 
 Every project has a different way of dealing with issues, so don't wonder if there's no comment on it, but somebody "labels" it with certain markers. This helps developers to more easily keep track of bugs and priorities. When any further input from you is required, you will be asked specifically. Do not bug anyone through other channels about resolving your issue.
 
-Once your issue is closed, you will know whether it was valid or turned out to be irreproducible. If you included all of the data from above in your report, chances are that the latter won't be the case.
+Once your issue is closed, you will know whether it was valid or turned out to be unreproducible. If you included all of the data from above in your report, chances are that the latter won't be the case.
+
+[Bug-Reports]: https://forums.minecraftforge.net/forum/18-support-bug-reports/
+[Modder-Support]: https://forums.minecraftforge.net/forum/70-modder-support/
+
+[Discord]: https://discord.minecraftforge.net/
+
+[Documentation]: https://docs.minecraftforge.net/

docs/assets/Forge_logo.svg

@@ -1,12 +1,7 @@
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-		<polygon points="437.69 407.72 437.69 400.36 456.41 400.36 456.41 390.09 437.69 390.09 437.69 383.77 457.44 383.77 457.44 373.5 426.72 373.5 426.72 417.99 458.48 417.99 458.48 407.72"/>
-	</g>
-	<path d="m243.63 379.09l-37.842-1.852 46.229-0.034v-3.727h-52.125l-1e-3 7.798v6.201c0 0.115-1.52-9.144-1.87-11.734h-4.098v13.029c0 0.123-1.753-10.888-1.939-12.264h-27.914c1.902 1.648 12.401 10.598 19.865 14.28 3.741 1.846 8.33 1.86 12.414 1.974 2.075 0.06 4.25 0.217 5.803 1.754 2.255 2.236 2.758 5.704 0.814 8.33-1.922 2.594-7.335 3.156-7.335 3.156l-4.509 5.531v6.424h10.251l0.319-6.348 8.863-6.285c-0.946 0.757-3.058 2.783-6.229 7.666-0.717 1.102-1.275 2.306-1.711 3.49 2.238-1.896 6.84-3.194 12.153-3.194 5.307 0 9.903 1.295 12.146 3.188-0.437-1.185-0.994-2.385-1.709-3.483-3.172-4.883-5.284-6.909-6.229-7.666l8.863 6.285 0.32 6.348h9.565v-6.424l-4.507-5.531s-6.675-0.425-8.423-3.156c-5.032-7.869 2.115-20.082 18.836-23.756z" fill="#1E2D41"/>
+<svg xmlns="http://www.w3.org/2000/svg" xml:space="preserve" viewBox="164.072 372.466 294.41 46.56">
+  <g fill="#DFA86A">
+    <path d="M266.16 417.99h10.96v-16.94h17.97v-10.27h-17.97v-7.01h19.06V373.5h-30.02zM337.33 378.7c-2.103-2.057-4.629-3.64-7.51-4.704-2.743-1.015-5.786-1.528-9.041-1.528l-.356.002c-3.362 0-6.503.556-9.338 1.651-2.857 1.106-5.357 2.707-7.434 4.761-2.073 2.052-3.714 4.559-4.877 7.45-1.158 2.876-1.748 6.104-1.748 9.59 0 3.417.59 6.582 1.753 9.403 1.163 2.829 2.807 5.297 4.88 7.329 2.073 2.03 4.572 3.621 7.425 4.724 2.834 1.096 5.975 1.651 9.339 1.651h.023c3.402-.043 6.57-.639 9.42-1.772 2.863-1.142 5.375-2.757 7.465-4.804 2.091-2.051 3.742-4.524 4.91-7.358 1.162-2.823 1.75-5.987 1.75-9.402 0-3.487-.588-6.705-1.748-9.568-1.168-2.874-2.82-5.371-4.913-7.425zm-4.644 16.762c0 1.96-.302 3.782-.896 5.413-.587 1.607-1.42 3.011-2.479 4.167-1.05 1.147-2.335 2.065-3.821 2.728-1.479.656-3.164.99-5.008.99-1.84 0-3.514-.333-4.973-.988-1.47-.662-2.747-1.578-3.799-2.729-1.062-1.156-1.895-2.559-2.479-4.167-.595-1.63-.896-3.451-.896-5.413 0-1.801.298-3.497.887-5.044.584-1.536 1.419-2.894 2.479-4.037 1.048-1.132 2.323-2.03 3.792-2.674 1.465-.642 3.145-.968 4.988-.968 1.848 0 3.539.326 5.025.971 1.481.643 2.766 1.541 3.812 2.671 1.062 1.143 1.896 2.501 2.479 4.036.589 1.548.889 3.245.889 5.044zM376.27 395.65c1.902-2.327 2.867-5.221 2.867-8.603 0-2.614-.508-4.84-1.506-6.613-.997-1.762-2.354-3.188-4.035-4.234-1.603-.995-3.445-1.705-5.482-2.114-1.938-.388-3.969-.583-6.037-.583h-16.021v44.487h10.961v-17.282h2.35l9.447 17.282h13.127l-11.199-18.646c2.262-.728 4.116-1.964 5.528-3.694zm-19.254-12.223h4.426c.844 0 1.73.054 2.636.16.784.094 1.503.283 2.132.568.496.225.888.553 1.193.998.283.415.428 1.031.428 1.836 0 .931-.16 1.643-.459 2.06-.34.472-.771.813-1.32 1.046-.686.289-1.459.477-2.301.554-.975.089-1.963.136-2.938.136h-3.795l-.002-7.358z"/>
+    <path d="M394.82 386.38c1.05-1.132 2.325-2.03 3.793-2.674 1.464-.642 3.144-.968 4.988-.968 1.843 0 3.611.311 5.26.921 1.609.599 2.992 1.449 4.107 2.531l1.314 1.278 8.019-8.105-1.454-1.298c-2.355-2.103-5.066-3.586-8.058-4.407-2.879-.789-5.987-1.189-9.247-1.189-3.361 0-6.503.556-9.339 1.651-2.856 1.106-5.355 2.707-7.431 4.761-2.074 2.052-3.716 4.559-4.88 7.45-1.158 2.876-1.746 6.104-1.746 9.59 0 3.417.59 6.582 1.752 9.403 1.164 2.829 2.807 5.297 4.88 7.329 2.073 2.03 4.572 3.621 7.425 4.724 2.832 1.096 5.975 1.651 9.339 1.651 6.501 0 12.475-1.432 17.751-4.25l.979-.522v-23.814h-19.313v10.27h8.354v6.639c-.871.397-1.834.709-2.881.933-1.5.314-3.127.478-4.83.478-1.841 0-3.514-.333-4.973-.988-1.472-.662-2.748-1.578-3.801-2.729-1.06-1.156-1.893-2.559-2.478-4.167-.595-1.63-.896-3.451-.896-5.413 0-1.801.299-3.497.887-5.044.586-1.54 1.421-2.897 2.479-4.041zM437.69 407.72v-7.36h18.72v-10.27h-18.72v-6.32h19.75V373.5h-30.72v44.49h31.76v-10.27z"/>
+  </g>
+  <path fill="#1E2D41" d="m243.63 379.09-37.842-1.852 46.229-.034v-3.727h-52.125l-.001 7.798v6.201c0 .115-1.52-9.144-1.87-11.734h-4.098v13.029c0 .123-1.753-10.888-1.939-12.264H164.07c1.902 1.648 12.401 10.598 19.865 14.28 3.741 1.846 8.33 1.86 12.414 1.974 2.075.06 4.25.217 5.803 1.754 2.255 2.236 2.758 5.704.814 8.33-1.922 2.594-7.335 3.156-7.335 3.156l-4.509 5.531v6.424h10.251l.319-6.348 8.863-6.285c-.946.757-3.058 2.783-6.229 7.666-.717 1.102-1.275 2.306-1.711 3.49 2.238-1.896 6.84-3.194 12.153-3.194 5.307 0 9.903 1.295 12.146 3.188-.437-1.185-.994-2.385-1.709-3.483-3.172-4.883-5.284-6.909-6.229-7.666l8.863 6.285.32 6.348h9.565v-6.424l-4.507-5.531s-6.675-.425-8.423-3.156c-5.032-7.869 2.115-20.082 18.836-23.756z"/>
 </svg>

dump.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+for file in $(find repo | grep --invert-match -e md5 -e sha | grep -e .jar -e .zip); do
+    file_path=$(realpath $file)
+    file_name=$(basename $file)
+    
+    echo "$file_name"
+    files=$(unzip -l $file | awk '{print $4}')
+    for f in $files; do
+        out="_actual/$file_name/$f"
+        parent=$(dirname "$out")
+        echo $out
+        
+        if [ ! -d "$parent" ]; then
+            mkdir -p "$parent"
+        fi
+            
+        if [[ $f == *.class ]]; then
+            javap -v -p jar:file://$file_path!/$f | tail -n +4 >$out.txt
+        elif [[ $f != */ && $f != "Name" && $f != "----" ]]; then
+            unzip -o -q $file $f -d _actual/$file_name
+        fi
+    done
+done

fmlcore/build.gradle

@@ -1,64 +1,68 @@
-plugins {
-    id 'com.github.ben-manes.versions'
-    id 'org.javamodularity.moduleplugin' version '1.8.3' apply false
-}
-apply plugin: 'java-library'
-apply plugin: 'jacoco'
-apply plugin: 'org.javamodularity.moduleplugin'
+import net.minecraftforge.gradleutils.PomUtils
 
-dependencyUpdates.rejectVersionIf { isNonStable(it.candidate.version) }
+plugins {
+    id 'java-library'
+    id 'maven-publish'
+    id 'net.minecraftforge.licenser'
+    id 'net.minecraftforge.gradleutils'
+}
+
+apply from: rootProject.file('build_shared.gradle')
 
 dependencies {
-    compileOnly('org.jetbrains:annotations:21.0.1')
+    compileOnly(libs.jetbrains.annotations)
+
+    api(libs.eventbus)
+    annotationProcessor(libs.eventbus.validator)
+
     implementation(project(':fmlloader'))
-    api('net.minecraftforge:eventbus:5.0.+')
-    implementation('commons-io:commons-io:2.5')
+    implementation(libs.commons.io)
 }
 
-task sourcesJar(type: Jar) {
-    archiveClassifier = 'sources'
-    from sourceSets.main.allSource
+java {
+    toolchain.languageVersion = JavaLanguageVersion.of(JAVA_VERSION)
+    withSourcesJar()
 }
 
-ext {
-    MANIFESTS = [
-        '': [
-            'FMLModType': 'LIBRARY',
-            'Timestamp': new Date().format("yyyy-MM-dd'T'HH:mm:ssZ"),
-            'Git-Commit': GIT_INFO.abbreviatedId,
-            'Git-Branch': GIT_INFO.branch,
-            'Build-Number': "${System.getenv('BUILD_NUMBER')?:0}"
-        ] as LinkedHashMap,
-        'net/minecraftforge/fml/loading/': [
-            'Specification-Title':      'FMLLoader',
+tasks.named('jar', Jar).configure {
+    manifest {
+        attributes([
+            'Automatic-Module-Name': 'net.minecraftforge.fmlcore',
+            'FMLModType': 'LIBRARY'
+        ] as LinkedHashMap)
+        attributes([
+            'Specification-Title':      'FML',
             'Specification-Vendor':     'Forge Development LLC',
             'Specification-Version':    '1',
-            'Implementation-Title':     'FML Loader',
+            'Implementation-Title':     'FML',
             'Implementation-Version':   '1.0',
-            'Implementation-Vendor':    'Forge'
-        ] as LinkedHashMap
-    ]
-}
-
-jar.doFirst {
-    MANIFESTS.each { pkg, values ->
-        if (pkg == '')
-            manifest.attributes(values)
-        else
-            manifest.attributes(values, pkg)
+            'Implementation-Vendor':    'Forge Development LLC'
+        ] as LinkedHashMap, 'net/minecraftforge/fml/')
     }
 }
 
-tasks.withType(JavaCompile) {
-    options.compilerArgs << '-Xlint:unchecked'
+tasks.withType(JavaCompile).configureEach {
+    options.compilerArgs << '-Xlint:-unchecked'
 }
 
-artifacts {
-    archives jar
-    archives sourcesJar
+license {
+    header = rootProject.file('LICENSE-header.txt')
 }
 
-publishing.publications.mavenJava(MavenPublication) {
-    from components.java
-    artifact sourcesJar
-}
+publishing {
+    publications.register('mavenJava', MavenPublication).configure {
+        from components.java
+        artifactId = 'fmlcore'
+        pom {
+            name = project.name
+            description = 'Modifactions to Minecraft to enable mod developers.'
+            url = 'https://github.com/MinecraftForge/MinecraftForge'
+            PomUtils.setGitHubDetails(pom, 'MinecraftForge')
+            license PomUtils.Licenses.LGPLv2_1
+        }
+    }
+    
+    repositories {
+        maven gradleutils.publishingForgeMaven
+    }
+}

fmlcore/src/main/java/net/minecraftforge/fml/Bindings.java

@@ -1,35 +1,43 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
-import cpw.mods.modlauncher.util.ServiceLoaderUtils;
-import net.minecraftforge.eventbus.api.IEventBus;
+import net.minecraftforge.eventbus.api.bus.BusGroup;
 import net.minecraftforge.fml.config.IConfigEvent;
 import net.minecraftforge.fml.loading.FMLLoader;
 
+import java.util.ServiceConfigurationError;
 import java.util.ServiceLoader;
 import java.util.function.Supplier;
 
+/**
+ * Used to allow access to certain things from the game layer
+ */
 public class Bindings {
-    private static final Bindings INSTANCE = new Bindings();
+    private Bindings() {}
 
-    private final IBindingsProvider provider;
+    /**
+     * The provider of the bindings
+     * @implNote May also throw a {@link ServiceConfigurationError}
+     */
+    private static final IBindingsProvider PROVIDER = ServiceLoader.load(FMLLoader.getGameLayer(), IBindingsProvider.class)
+            .findFirst().orElseThrow(() -> new IllegalStateException("Could not find bindings provider"));
 
-    private Bindings() {
-        final var providers = ServiceLoaderUtils.streamServiceLoader(()->ServiceLoader.load(FMLLoader.getGameLayer(), IBindingsProvider.class), sce->{}).toList();
-        if (providers.size() != 1) {
-            throw new IllegalStateException("Could not find bindings provider");
-        }
-        this.provider = providers.get(0);
-    }
-
-    public static Supplier<IEventBus> getForgeBus() {
-        return INSTANCE.provider.getForgeBusSupplier();
+    /**
+     * @return A supplier of net.minecraftforge.common.MinecraftForge#EVENT_BUS
+     */
+    public static Supplier<BusGroup> getForgeBus() {
+        return PROVIDER.getForgeBusSupplier();
     }
 
     public static Supplier<I18NParser> getMessageParser() {
-        return INSTANCE.provider.getMessageParser();
+        return PROVIDER.getMessageParser();
     }
 
     public static Supplier<IConfigEvent.ConfigConfig> getConfigConfiguration() {
-        return INSTANCE.provider.getConfigConfiguration();
+        return PROVIDER.getConfigConfiguration();
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/CrashReportCallables.java

@@ -1,32 +1,97 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
+import com.mojang.logging.LogUtils;
+import org.slf4j.Logger;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.function.BooleanSupplier;
 import java.util.function.Supplier;
 
-public class CrashReportCallables {
+public class CrashReportCallables
+{
+    private static final Logger LOGGER = LogUtils.getLogger();
     private static final List<ISystemReportExtender> crashCallables = Collections.synchronizedList(new ArrayList<>());
 
+    /**
+     * Register a custom {@link ISystemReportExtender}
+     */
     public static void registerCrashCallable(ISystemReportExtender callable)
     {
         crashCallables.add(callable);
     }
 
-    public static void registerCrashCallable(String headerName, Supplier<String> reportGenerator) {
-        registerCrashCallable(new ISystemReportExtender() {
+    /**
+     * Register a {@link ISystemReportExtender system report extender} with the given header name and content
+     * generator, which will always be appended to the system report
+     * @param headerName The name of the system report entry
+     * @param reportGenerator The report generator to be called when a crash report is built
+     */
+    public static void registerCrashCallable(String headerName, Supplier<String> reportGenerator)
+    {
+        registerCrashCallable(new ISystemReportExtender()
+        {
             @Override
-            public String getLabel() {
+            public String getLabel()
+            {
                 return headerName;
             }
+
             @Override
-            public String get() {
+            public String get()
+            {
                 return reportGenerator.get();
             }
         });
     }
 
-    public static List<ISystemReportExtender> allCrashCallables() {
+    /**
+     * Register a {@link ISystemReportExtender system report extender} with the given header name and content
+     * generator, which will only be appended to the system report when the given {@link BooleanSupplier} returns true
+     * @param headerName The name of the system report entry
+     * @param reportGenerator The report generator to be called when a crash report is built
+     * @param active The supplier of the flag to be checked when a crash report is built
+     */
+    public static void registerCrashCallable(String headerName, Supplier<String> reportGenerator, BooleanSupplier active)
+    {
+        registerCrashCallable(new ISystemReportExtender()
+        {
+            @Override
+            public String getLabel()
+            {
+                return headerName;
+            }
+
+            @Override
+            public String get()
+            {
+                return reportGenerator.get();
+            }
+
+            @Override
+            public boolean isActive()
+            {
+                try
+                {
+                    return active.getAsBoolean();
+                }
+                catch (Throwable t)
+                {
+                    LOGGER.warn("CrashCallable '{}' threw an exception while checking the active flag, disabling", headerName, t);
+                    return false;
+                }
+            }
+        });
+    }
+
+    public static List<ISystemReportExtender> allCrashCallables()
+    {
         return List.copyOf(crashCallables);
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/DeferredWorkQueue.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
@@ -25,9 +11,11 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
 import java.util.concurrent.ConcurrentLinkedDeque;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
 import java.util.function.Supplier;
 
 import com.google.common.base.Stopwatch;
@@ -67,17 +55,31 @@ public class DeferredWorkQueue
     public void runTasks() {
         if (tasks.isEmpty()) return;
         LOGGER.debug(LOADING, "Dispatching synchronous work for work queue {}: {} jobs", modLoadingStage, tasks.size());
+        RuntimeException aggregate = new RuntimeException();
         Stopwatch timer = Stopwatch.createStarted();
-        tasks.forEach(t->makeRunnable(t, Runnable::run));
+        for (TaskInfo t : tasks) {
+            makeRunnable(t, Runnable::run, aggregate);
+        }
         timer.stop();
-        LOGGER.debug(LOADING, "Synchronous work queue completed in {}", timer);
+        if (aggregate.getSuppressed().length > 0) {
+            LOGGER.fatal(
+                    LOADING,
+                    "Synchronous work queue completed exceptionally in {}, see suppressed exceptions for details:",
+                    timer,
+                    aggregate
+            );
+            throw aggregate;
+        } else {
+            LOGGER.debug(LOADING, "Synchronous work queue completed in {}", timer);
+        }
     }
 
-    private static void makeRunnable(TaskInfo ti, Executor executor) {
+    private static void makeRunnable(TaskInfo ti, Executor executor, RuntimeException aggregate) {
         executor.execute(() -> {
             Stopwatch timer = Stopwatch.createStarted();
             ModLoadingContext.get().setActiveContainer(ti.owner);
             try {
+                ti.future.exceptionally(t -> captureException(ti.owner.getModId(), aggregate, t));
                 ti.task.run();
             } finally {
                 ModLoadingContext.get().setActiveContainer(null);
@@ -89,13 +91,38 @@ public class DeferredWorkQueue
         });
     }
 
+    private static <T> T captureException(String modId, RuntimeException aggregate, Throwable throwable) {
+        if (throwable instanceof CompletionException ce) {
+            throwable = ce.getCause();
+        }
+        aggregate.addSuppressed(throwable);
+        LOGGER.error("Mod '{}' encountered an error in a deferred task:", modId, throwable);
+        return null;
+    }
+
     public CompletableFuture<Void> enqueueWork(final ModContainer modInfo, final Runnable work) {
-        return CompletableFuture.runAsync(work, r->tasks.add(new TaskInfo(modInfo, r)));
+        return enqueueWork(modInfo, taskInfo -> CompletableFuture.runAsync(work, r -> taskInfo.task = r));
     }
 
     public <T> CompletableFuture<T> enqueueWork(final ModContainer modInfo, final Supplier<T> work) {
-        return CompletableFuture.supplyAsync(work, r->tasks.add(new TaskInfo(modInfo, r)));
+        return enqueueWork(modInfo, taskInfo -> CompletableFuture.supplyAsync(work, r -> taskInfo.task = r));
     }
 
-    record TaskInfo(ModContainer owner, Runnable task) {}
+    private <T> CompletableFuture<T> enqueueWork(final ModContainer modInfo, Function<TaskInfo, CompletableFuture<T>> futureGen) {
+        TaskInfo taskInfo = new TaskInfo(modInfo);
+        CompletableFuture<T> future = futureGen.apply(taskInfo);
+        taskInfo.future = future;
+        tasks.add(taskInfo);
+        return future;
+    }
+
+    private static final class TaskInfo {
+        private final ModContainer owner;
+        private Runnable task;
+        private CompletableFuture<?> future;
+
+        private TaskInfo(ModContainer owner) {
+            this.owner = owner;
+        }
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/DistExecutor.java

@@ -1,276 +0,0 @@
-/*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- */
-
-package net.minecraftforge.fml;
-
-import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.fml.loading.FMLEnvironment;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-
-import java.io.Serializable;
-import java.lang.invoke.SerializedLambda;
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.util.Objects;
-import java.util.concurrent.Callable;
-import java.util.function.Supplier;
-
-/**
- * Use to execute code conditionally based on sidedness.
- * <ul>
- * <li>When you want to call something on one side and return a result {@link #safeCallWhenOn(Dist, Supplier)}</li>
- * <li>When you want to call one thing on one side, another thing on the other and return a result {@link #safeRunForDist(Supplier, Supplier)}</li>
- * <li>When you want to run something on one side {@link #safeRunWhenOn(Dist, Supplier)}</li>
- * </ul>
- */
-public final class DistExecutor
-{
-    private static final Logger LOGGER = LogManager.getLogger();
-    private DistExecutor() {}
-
-    /**
-     * Run the callable in the supplier only on the specified {@link Dist}.
-     * This method is NOT sided-safe and special care needs to be taken in code using this method that implicit class
-     * loading is not triggered by the Callable.
-     *
-     * This method can cause unexpected ClassNotFound exceptions.
-     *
-     * Use {@link #safeCallWhenOn(Dist, Supplier)} where possible.
-     *
-     * @param dist The dist to run on
-     * @param toRun A supplier of the callable to run (Supplier wrapper to ensure classloading only on the appropriate dist)
-     * @param <T> The return type from the callable
-     * @return The callable's result
-     * @deprecated use {@link #safeCallWhenOn(Dist, Supplier)} instead. This remains for advanced use cases.
-     */
-    @Deprecated
-    public static <T> T callWhenOn(Dist dist, Supplier<Callable<T>> toRun) {
-        return unsafeCallWhenOn(dist, toRun);
-    }
-
-    public static <T> T unsafeCallWhenOn(Dist dist, Supplier<Callable<T>> toRun) {
-        if (dist == FMLEnvironment.dist) {
-            try
-            {
-                return toRun.get().call();
-            }
-            catch (Exception e)
-            {
-                throw new RuntimeException(e);
-            }
-        }
-        return null;
-    }
-
-    /**
-     * Call the SafeCallable when on the correct {@link Dist}.
-     *
-     * <strong>The lambda supplied here is required to be a method reference to a method defined in
-     * another class, otherwise an invalid SafeReferent error will be thrown</strong>
-     * @param dist the dist which this will run on
-     * @param toRun the SafeCallable to run and return the result from
-     * @param <T> The type of the SafeCallable
-     * @return the result of the SafeCallable or null if on the wrong side
-     */
-    public static <T> T safeCallWhenOn(Dist dist, Supplier<SafeCallable<T>> toRun) {
-        validateSafeReferent(toRun);
-        return callWhenOn(dist, toRun::get);
-    }
-
-    /**
-     * Runs the supplied Runnable on the speicified side. Same warnings apply as {@link #callWhenOn(Dist, Supplier)}.
-     *
-     * This method can cause unexpected ClassNotFound exceptions.
-     *
-     * @see #callWhenOn(Dist, Supplier)
-     * @param dist Dist to run this code on
-     * @param toRun The code to run
-     * @deprecated use {@link #safeRunWhenOn(Dist, Supplier)} where possible. Advanced uses only.
-     */
-    @Deprecated
-    public static void runWhenOn(Dist dist, Supplier<Runnable> toRun) {
-        unsafeRunWhenOn(dist, toRun);
-    }
-    /**
-     * Runs the supplied Runnable on the speicified side. Same warnings apply as {@link #unsafeCallWhenOn(Dist, Supplier)}.
-     *
-     * This method can cause unexpected ClassNotFoundException problems in common scenarios. Understand the pitfalls of
-     * the way the class verifier works to load classes before using this.
-     *
-     * Use {@link #safeRunWhenOn(Dist, Supplier)} if you can.
-     *
-     * @see #unsafeCallWhenOn(Dist, Supplier)
-     * @param dist Dist to run this code on
-     * @param toRun The code to run
-     */
-    public static void unsafeRunWhenOn(Dist dist, Supplier<Runnable> toRun) {
-        if (dist == FMLEnvironment.dist) {
-            toRun.get().run();
-        }
-    }
-
-    /**
-     * Call the supplied SafeRunnable when on the correct Dist.
-     * @param dist The dist to run on
-     * @param toRun The code to run
-     */
-    public static void safeRunWhenOn(Dist dist, Supplier<SafeRunnable> toRun) {
-        validateSafeReferent(toRun);
-        if (dist == FMLEnvironment.dist)  {
-            toRun.get().run();
-        }
-    }
-    /**
-     * Executes one of the two suppliers, based on which side is active.
-     *
-     * <p>
-     *     Example (replacement for old SidedProxy):<br/>
-     * {@code Proxy p = DistExecutor.runForDist(()->ClientProxy::new, ()->ServerProxy::new);}
-     *
-     * NOTE: the double supplier is required to avoid classloading the secondary target.
-     *
-     * @param clientTarget The supplier supplier to run when on the {@link Dist#CLIENT}
-     * @param serverTarget The supplier supplier to run when on the {@link Dist#DEDICATED_SERVER}
-     * @param <T> The common type to return
-     * @return The returned instance
-     * @deprecated Use {@link #safeRunForDist(Supplier, Supplier)}
-     */
-    @Deprecated
-    public static <T> T runForDist(Supplier<Supplier<T>> clientTarget, Supplier<Supplier<T>> serverTarget) {
-        return unsafeRunForDist(clientTarget, serverTarget);
-    }
-
-    /**
-     * Unsafe version of {@link #safeRunForDist(Supplier, Supplier)}. Use only when you know what you're doing
-     * and understand why the verifier can cause unexpected ClassNotFoundException crashes even when code is apparently
-     * not sided. Ensure you test both sides fully to be confident in using this.
-     *
-     * @param clientTarget The supplier supplier to run when on the {@link Dist#CLIENT}
-     * @param serverTarget The supplier supplier to run when on the {@link Dist#DEDICATED_SERVER}
-     * @param <T> The common type to return
-     * @return The returned instance
-     */
-    public static <T> T unsafeRunForDist(Supplier<Supplier<T>> clientTarget, Supplier<Supplier<T>> serverTarget) {
-        switch (FMLEnvironment.dist)
-        {
-            case CLIENT:
-                return clientTarget.get().get();
-            case DEDICATED_SERVER:
-                return serverTarget.get().get();
-            default:
-                throw new IllegalArgumentException("UNSIDED?");
-        }
-    }
-    /**
-     * Executes one of the two suppliers, based on which side is active.
-     *
-     * <p>
-     *     Example (replacement for old SidedProxy):<br/>
-     * {@code Proxy p = DistExecutor.safeRunForDist(()->ClientProxy::new, ()->ServerProxy::new);}
-     *
-     * NOTE: the double supplier is required to avoid classloading the secondary target.
-     *
-     * @param clientTarget The supplier supplier to run when on the {@link Dist#CLIENT}
-     * @param serverTarget The supplier supplier to run when on the {@link Dist#DEDICATED_SERVER}
-     * @param <T> The common type to return
-     * @return The returned instance
-     */
-    public static <T> T safeRunForDist(Supplier<SafeSupplier<T>> clientTarget, Supplier<SafeSupplier<T>> serverTarget) {
-        validateSafeReferent(clientTarget);
-        validateSafeReferent(serverTarget);
-        switch (FMLEnvironment.dist)
-        {
-            case CLIENT:
-                return clientTarget.get().get();
-            case DEDICATED_SERVER:
-                return serverTarget.get().get();
-            default:
-                throw new IllegalArgumentException("UNSIDED?");
-        }
-    }
-
-    /**
-     * A safe referent. This will assert that it is being called via a separated class method reference. This will
-     * avoid the common pitfalls of {@link #callWhenOn(Dist, Supplier)} above.
-     *
-     * SafeReferents assert that they are defined as a separate method outside the scope of the calling class.
-     *
-     * <strong>Implementations need to be defined in a separate class to the referring site, with appropriate
-     * visibility to be accessible at the callsite (generally, avoid private methods).</strong>
-     *
-     * <p>
-     * Valid:<br/>
-     *
-     * {@code DistExecutor.safeCallWhenOn(Dist.CLIENT, ()->AnotherClass::clientOnlyMethod);}
-     *
-     * <p>
-     * Invalid:<br/>
-     *
-     * {@code DistExecutor.safeCallWhenOn(Dist.CLIENT, ()->()->Minecraft.getInstance().world);}
-     */
-    public interface SafeReferent {}
-
-    /**
-     * SafeCallable version of {@link SafeReferent}.
-     * @see SafeReferent
-     * @param <T> The return type of the Callable
-     */
-    public interface SafeCallable<T> extends SafeReferent, Callable<T>, Serializable {}
-
-    /**
-     * SafeSupplier version of {@link SafeReferent}
-     * @param <T> The return type of the Supplier
-     */
-    public interface SafeSupplier<T> extends SafeReferent, Supplier<T>, Serializable {}
-
-    /**
-     * SafeRunnable version of {@link SafeReferent}
-     */
-    public interface SafeRunnable extends SafeReferent, Runnable, Serializable {}
-
-    private static final void validateSafeReferent(Supplier<? extends SafeReferent> safeReferentSupplier) {
-        if (FMLEnvironment.production) return;
-        final SafeReferent setter;
-        try {
-            setter = safeReferentSupplier.get();
-        } catch (Exception e) {
-            // Typically a class cast exception, just return out, expected.
-            return;
-        }
-
-        for (Class<?> cl = setter.getClass(); cl != null; cl = cl.getSuperclass()) {
-            try {
-                Method m = cl.getDeclaredMethod("writeReplace");
-                m.setAccessible(true);
-                Object replacement = m.invoke(setter);
-                if (!(replacement instanceof SerializedLambda))
-                    break;// custom interface implementation
-                SerializedLambda l = (SerializedLambda) replacement;
-                if (Objects.equals(l.getCapturingClass(), l.getImplClass())) {
-                    LOGGER.fatal("Detected unsafe referent usage, please view the code at {}",Thread.currentThread().getStackTrace()[3]);
-                    throw new RuntimeException("Unsafe Referent usage found in safe referent method");
-                }
-            } catch (NoSuchMethodException e) {
-            } catch (IllegalAccessException | InvocationTargetException e) {
-                break;
-            }
-        }
-    }
-}

fmlcore/src/main/java/net/minecraftforge/fml/I18NParser.java

@@ -1,3 +1,8 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
 public interface I18NParser {

fmlcore/src/main/java/net/minecraftforge/fml/IBindingsProvider.java

@@ -1,12 +1,17 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.IEventBus;
+import net.minecraftforge.eventbus.api.bus.BusGroup;
 import net.minecraftforge.fml.config.IConfigEvent;
 
 import java.util.function.Supplier;
 
 public interface IBindingsProvider {
-    Supplier<IEventBus> getForgeBusSupplier();
+    Supplier<BusGroup> getForgeBusSupplier();
     Supplier<I18NParser> getMessageParser();
     Supplier<IConfigEvent.ConfigConfig> getConfigConfiguration();
 }

fmlcore/src/main/java/net/minecraftforge/fml/ICrashCallable.java

@@ -0,0 +1,5 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+

fmlcore/src/main/java/net/minecraftforge/fml/IExtensionPoint.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
@@ -22,41 +8,114 @@ package net.minecraftforge.fml;
 import java.util.function.BiPredicate;
 import java.util.function.Supplier;
 
+/**
+ * An extension point for a mod container.
+ *
+ * <p>An extension point can be registered for a mod container using {@link ModContainer#registerExtensionPoint(Class, Supplier)}
+ * and retrieved (if present) using {@link ModContainer#getCustomExtension(Class)}. An extension point allows a mod to
+ * supply an arbitrary value as a record class to another mod or framework through their mod container class, avoiding
+ * the use of {@link InterModComms} or other external frameworks to pass around these values.</p>
+ *
+ * <p>The usual way to declare an extension point is to implement this interface on a record class, with the type
+ * parameter being a reference to the class itself. For example, {@code record MyExtension(...) extends
+ * IExtensionPoint<MyExtension>} would declare an extension point which supplies a {@code MyExtension} object. However,
+ * there is no hard requirement that an extension point's type parameter must be in reference to itself; the type
+ * parameter may reference another record class instead.</p>
+ *
+ * @param <T> the type of the record which is held by the extension point
+ */
+@SuppressWarnings("unused") // Type parameter T
+// TODO: Complete re-write, this hasnt actually be used in a generic way by mods and we could make it a lot simpler.
 public interface IExtensionPoint<T extends Record>
 {
     /**
-     * Compatibility display test for the mod.
-     * Used for displaying compatibility with remote servers with the same mod, and on disk saves.
+     * Extension point for the compatibility display test used on the server selection screen.
      *
-     * The supplier provides my "local" version for sending across the impl or writing to disk
-     * The predicate tests the version from a remote instance or save for acceptability (Boolean is true for impl, false for local save)
-     * and returns true if the version is compatible.
+     * <em>Note: "server" and "client" refers to the {@linkplain net.minecraftforge.api.distmarker.Dist#DEDICATED_SERVER dedicated server}
+     * and {@linkplain net.minecraftforge.api.distmarker.Dist#CLIENT game client} physical distributions, rather than the
+     * {@linkplain LogicalSide logical server and client}.</em>
      *
-     * <p>Return {@code net.minecraftforge.impl.impl.FMLNetworkConstants#IGNORESERVERONLY} in the supplier, if you wish to be ignored
-     * as a server side only mod.</p>
-     * <p>Return true in the predicate for all values of the input string (when impl boolean is true) if you are client side,
-     * and don't care about matching any potential server version.</p>
+     * <p>The {@link Supplier} provides the local compatibility version, which is sent from the server to the client
+     * for multiplayer connections or stored to disk for the world save. The {@link BiPredicate} accepts the remote
+     * compatibility version and a boolean indicating whether the remote version is from the server or a world save,
+     * where {@code true} means it is from the server and {@code false} means it is from the world save. The return
+     * value of the predicate determines whether the remote version is "compatible" for the purposes of the display test.</p>
      *
-     * <p>
-     * Examples: A server only mod
-     * </p>
+     * <p>The local compatibility version may be of the value {@link DisplayTest#IGNORESERVERONLY},
+     * in which case clients will ignore the mod's presence if it is present on the server but not on the client.
+     * However, the remote version test predicate must still accept this value as a remote version in order to display
+     * as compatible if the mod is present on the client.</p>
+     *
+     * <p><strong>The compatibility display test does not necessarily indicate the success or failure of an actual
+     * connection attempt.</strong> Factors such as display test extension misconfiguration, truncation of ping data,
+     * difference of registry data or network channels between server and client, and others may cause the result of the
+     * compatibility test to not reflect the actual likelihood of a connection successfully being established between
+     * the server and the client.</p>
+     *
+     * <p>An example declaration of a display test extension registration for a regular mod (requires to be present on
+     * server and client) is as follows:</p>
      * <pre>{@code
-     *     registerExtensionPoint(DISPLAYTEST, ()->Pair.of(
-     *      ()->FMLNetworkConstants.IGNORESERVERONLY, // ignore me, I'm a server only mod
-     *      (s,b)->true // i accept anything from the server or the save, if I'm asked
-     *     )
+     * String compatibilityVersion = "1"; // Could be linked with a network channel version or mod version
+     * ModLoadingContext.get().registerExtensionPoint(IExtensionPoint.DisplayTest.class,
+     *         () -> new IExtensionPoint.DisplayTest(
+     *                 () -> compatibilityVersion,
+     *                 (remoteVersion, isFromServer) -> remoteVersion.equals(compatibilityVersion)
+     *         )
+     * );
      * }</pre>
      *
-     * <p>
-     * Examples: A client only mod
-     * </p>
+     * <p>An example declaration of a display test extension registration for a <em>server-side-only</em> mod (does not
+     * require to be present on the client) is as follows:</p>
      * <pre>{@code
-     *     registerExtensionPoint(DISPLAYTEST, ()->Pair.of(
-     *      ()->"anything. i don't care", // if i'm actually on the server, this string is sent but i'm a client only mod, so it won't be
-     *      (remoteversionstring,networkbool)->networkbool // i accept anything from the server, by returning true if it's asking about the server
-     *     )
+     * ModLoadingContext.get().registerExtensionPoint(IExtensionPoint.DisplayTest.class,
+     *         () -> new IExtensionPoint.DisplayTest(
+     *                 // Ignore this mod if not present on the client
+     *                 () -> NetworkConstants.IGNORESERVERONLY,
+     *                 // If present on the client, accept any version if from a server
+     *                 (remoteVersion, isFromServer) -> isFromServer
+     *         )
+     * );
      * }</pre>
      *
+     * <p>An example declaration of a display test extension registration for a <em>client-side-only</em> mod (does not
+     * require to be present on the server) is as follows:</p>
+     * <pre>{@code
+     * ModLoadingContext.get().registerExtensionPoint(IExtensionPoint.DisplayTest.class,
+     *         () -> new IExtensionPoint.DisplayTest(
+     *                 // Send any version from server to client, since we will be accepting any version as well
+     *                 () -> "dQw4w9WgXcQ",
+     *                 // Accept any version on the client, from server or from save
+     *                 (remoteVersion, isFromServer) -> true
+     *         )
+     * );
+     * }</pre>
+     *
+     * @see net.minecraftforge.network.ServerStatusPing
+     * @see net.minecraftforge.client.ForgeHooksClient#processForgeListPingData(net.minecraft.network.protocol.status.ServerStatus, net.minecraft.client.multiplayer.ServerData)
      */
-    record DisplayTest(Supplier<String> suppliedVersion, BiPredicate<String, Boolean> remoteVersionTest) implements IExtensionPoint<DisplayTest> {}
+    @SuppressWarnings("JavadocReference") // reference to NetworkConstants, ForgeHooksClient
+    record DisplayTest(Supplier<String> suppliedVersion, BiPredicate<String, Boolean> remoteVersionTest) implements IExtensionPoint<DisplayTest> {
+        public static final String IGNORESERVERONLY = "SERVER_ONLY";
+
+        /**
+         * Ignores any version information coming from the server - use for server only mods
+         */
+        public static final Supplier<DisplayTest> IGNORE_SERVER_VERSION = () -> new DisplayTest(IGNORESERVERONLY, (remoteVersion, isFromServer) -> true);
+
+        /**
+         * Ignores all information and provides no information
+         * <p>Note: If your mod is purely client-side and has no multiplayer functionality (be it dedicated servers or
+         * Open to LAN), consider setting {@code clientSideOnly=true} in the root of your mods.toml.</p>
+         */
+        public static final Supplier<DisplayTest> IGNORE_ALL_VERSION = () -> new DisplayTest("", (remoteVersion, isFromServer) -> true);
+
+        /**
+         * An optional alternative to {@link #DisplayTest(Supplier, BiPredicate)} which accepts a constant version string
+         * instead of a {@link Supplier}.
+         * <p>Internally, the provided version string is wrapped in a Supplier for you.</p>
+         */
+        public DisplayTest(String version, BiPredicate<String, Boolean> remoteVersionTest) {
+            this(() -> version, remoteVersionTest);
+        }
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/IModLoadingState.java

@@ -1,25 +1,99 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.Event;
-import net.minecraftforge.fml.event.IModBusEvent;
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 
-import java.util.List;
-import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
-import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.function.IntSupplier;
+import java.util.function.Supplier;
 
+/**
+ * A mod loading state. During mod loading, the mod loader transitions between states in a defined sorted list of states,
+ * grouped into various {@link ModLoadingPhase phases}.
+ *
+ * @see IModStateProvider
+ */
+@NullMarked
 public interface IModLoadingState {
+    /**
+     * {@return the name of this state}
+     */
     String name();
-    String previous();
-    ModLoadingPhase phase();
-    Function<ModList, String> message();
-    Optional<Consumer<ModList>> inlineRunnable();
 
-    default <T extends Event & IModBusEvent> Optional<CompletableFuture<List<Throwable>>> buildTransition(final Executor syncExecutor, final Executor parallelExecutor) {
-        return buildTransition(syncExecutor, parallelExecutor, e->CompletableFuture.runAsync(()->{}, e), e->CompletableFuture.runAsync(()->{}, e));
+    /**
+     * {@return the name of the state immediately previous to this state} This may be a blank name, which indicates this
+     * is either the first mod loading state or an exceptional mod loading state (such as a situation where errors
+     * prevent the loading process from continuing normally).
+     */
+    String previous();
+
+    /**
+     * {@return the mod loading phase this state belongs to} For exceptional mod loading states, this should be
+     * {@link ModLoadingPhase#ERROR}.
+     */
+    ModLoadingPhase phase();
+
+    /**
+     * {@return a function returning a human-friendly message for this state}
+     */
+    Supplier<String> message();
+
+    /**
+     * @return a function that computes the size of this transition based on the size of the modlist.
+     * Used to compute progress.
+     */
+    default IntSupplier size() {
+        return ModList::size;
     }
 
-    <T extends Event & IModBusEvent> Optional<CompletableFuture<List<Throwable>>> buildTransition(Executor syncExecutor, Executor parallelExecutor, Function<Executor, CompletableFuture<Void>> preSyncTask, Function<Executor, CompletableFuture<Void>> postSyncTask);
+    /**
+     * {@return an optional runnable, which runs before starting the transition from this state to the next}
+     * @see #buildTransition(Executor, Executor, ProgressMeter, Function, Function)
+     */
+    @Nullable Runnable inlineRunnable();
+
+    /**
+     * Builds the transition task for this state with a blank pre-sync and post-sync task.
+     *
+     * @param syncExecutor     a synchronous executor
+     * @param parallelExecutor a parallel executor
+     * @param progressBar      a progress meter for tracking progress
+     * @return a transition task for this state
+     * @see #buildTransition(Executor, Executor, ProgressMeter, Function, Function)
+     */
+    default @Nullable CompletableFuture<Void> buildTransition(
+        final Executor syncExecutor,
+        final Executor parallelExecutor,
+        final ProgressMeter progressBar
+    ) {
+        return buildTransition(syncExecutor, parallelExecutor, progressBar,
+            _ -> CompletableFuture.completedFuture(null),
+            _ -> CompletableFuture.completedFuture(null)
+        );
+    }
+
+    /**
+     * Builds the transition task for this state. The pre-sync and post-sync task functions allow the transition builder
+     * to run these tasks on the same executor as the actual event dispatch and pre/post hooks.
+     *
+     * @param syncExecutor     a synchronous executor
+     * @param parallelExecutor a parallel executor
+     * @param progressBar      a progress meter for tracking progress
+     * @param preSyncTask      a function which returns a task to run before event pre-dispatch hook
+     * @param postSyncTask     a function which returns a task to run after event post-dispatch hook
+     * @return a transition task for this state
+     */
+    @Nullable CompletableFuture<Void> buildTransition(final Executor syncExecutor,
+                                                      final Executor parallelExecutor,
+                                                      final ProgressMeter progressBar,
+                                                      final Function<Executor, CompletableFuture<Void>> preSyncTask,
+                                                      final Function<Executor, CompletableFuture<Void>> postSyncTask);
 }

fmlcore/src/main/java/net/minecraftforge/fml/IModStateProvider.java

@@ -1,7 +1,21 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
 import java.util.List;
 
+/**
+ * Provides a list of mod loading states which the mod loader may transition between.
+ *
+ * <p>There may be multiple mod state providers in a single application, where all states from each provider is
+ * combined into a single list and ordered.</p>
+ */
 public interface IModStateProvider {
+    /**
+     * {@return the list of mod loading states known to this provider}
+     */
     List<IModLoadingState> getAllStates();
 }

fmlcore/src/main/java/net/minecraftforge/fml/IModStateTransition.java

@@ -1,87 +1,51 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.Event;
 import net.minecraftforge.fml.event.IModBusEvent;
 
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
 import java.util.function.BiFunction;
 import java.util.function.Function;
-import java.util.function.Supplier;
-import java.util.stream.Stream;
 
-@SuppressWarnings("unchecked")
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+import org.jetbrains.annotations.Nullable;
+
 public interface IModStateTransition {
     static IModStateTransition buildNoopTransition() {
-        return new NoopTransition();
+        return ModStateTransitionHelper.NOOP;
     }
 
-    default <T extends Event & IModBusEvent> CompletableFuture<List<Throwable>> build(Executor syncExecutor, Executor parallelExecutor, Function<Executor, CompletableFuture<Void>> preSyncTask, Function<Executor, CompletableFuture<Void>> postSyncTask) {
-        List<CompletableFuture<List<Throwable>>> cfs = new ArrayList<>();
-        this.eventFunctionStream().get()
-                .map(f->(EventGenerator<T>)f)
-                .reduce((head, tail)-> addCompletableFutureTaskForModDispatch(syncExecutor, parallelExecutor, cfs, head, ModLoadingStage::currentState, tail))
-                .ifPresent(last-> addCompletableFutureTaskForModDispatch(syncExecutor, parallelExecutor, cfs, last, nextModLoadingStage(), null));
-        final CompletableFuture<Void> preSyncTaskCF = preSyncTask.apply(syncExecutor);
-        final CompletableFuture<List<Throwable>> eventDispatchCF = ModList.gather(cfs).thenCompose(ModList::completableFutureFromExceptionList);
-        final CompletableFuture<List<Throwable>> postEventDispatchCF = preSyncTaskCF.thenComposeAsync(n -> eventDispatchCF, parallelExecutor).thenApply(r -> {
-            postSyncTask.apply(syncExecutor);
-            return r;
-        });
-        return this.finalActivityGenerator().apply(syncExecutor, postEventDispatchCF);
+    default CompletableFuture<Void> build(
+        final String name,
+        final Executor syncExecutor,
+        final Executor parallelExecutor,
+        final ProgressMeter progressBar,
+        final Function<Executor, CompletableFuture<Void>> preSyncTask,
+        final Function<Executor, CompletableFuture<Void>> postSyncTask
+    ) {
+        return ModStateTransitionHelper.build(this, name, syncExecutor, parallelExecutor, progressBar, preSyncTask, postSyncTask);
     }
 
     default BiFunction<ModLoadingStage, Throwable, ModLoadingStage> nextModLoadingStage() {
         return ModLoadingStage::nextState;
     }
 
-    private <T extends Event & IModBusEvent> EventGenerator<T> addCompletableFutureTaskForModDispatch(final Executor syncExecutor, final Executor parallelExecutor, final List<CompletableFuture<List<Throwable>>> completeableFutures, final EventGenerator<T> eventGenerator, BiFunction<ModLoadingStage, Throwable, ModLoadingStage> nextState, final EventGenerator<T> nextGenerator) {
-        completeableFutures.add(((BiFunction<Executor, EventGenerator<T>, CompletableFuture<List<Throwable>>>)preDispatchHook()).apply(threadSelector().apply(syncExecutor, parallelExecutor), eventGenerator));
-        completeableFutures.add(ModList.get().futureVisitor(eventGenerator, nextState).apply(threadSelector().apply(syncExecutor, parallelExecutor)));
-        completeableFutures.add(((BiFunction<Executor, EventGenerator<T>, CompletableFuture<List<Throwable>>>)postDispatchHook()).apply(threadSelector().apply(syncExecutor, parallelExecutor), eventGenerator));
-        return nextGenerator;
+    @Nullable
+    default <T extends IModBusEvent> EventGenerator<T> eventFunction() {
+        return null;
     }
 
-    Supplier<Stream<EventGenerator<?>>> eventFunctionStream();
     ThreadSelector threadSelector();
-    BiFunction<Executor, CompletableFuture<List<Throwable>>, CompletableFuture<List<Throwable>>> finalActivityGenerator();
-    BiFunction<Executor, ? extends EventGenerator<?>, CompletableFuture<List<Throwable>>> preDispatchHook();
-    BiFunction<Executor, ? extends EventGenerator<?>, CompletableFuture<List<Throwable>>> postDispatchHook();
+    BiFunction<Executor, CompletableFuture<Void>, CompletableFuture<Void>> finalActivityGenerator();
 
-    interface EventGenerator<T extends Event & IModBusEvent> extends Function<ModContainer, T> {
-        static <FN extends Event & IModBusEvent> EventGenerator<FN> fromFunction(Function<ModContainer, FN> fn) {
+    interface EventGenerator<T extends IModBusEvent> extends Function<ModContainer, T> {
+        static <FN extends IModBusEvent> EventGenerator<FN> fromFunction(Function<ModContainer, FN> fn) {
             return fn::apply;
         }
     }
 }
-
-record NoopTransition() implements IModStateTransition {
-
-    @Override
-    public Supplier<Stream<EventGenerator<?>>> eventFunctionStream() {
-        return Stream::of;
-    }
-
-    @Override
-    public ThreadSelector threadSelector() {
-        return ThreadSelector.SYNC;
-    }
-
-    @Override
-    public BiFunction<Executor, CompletableFuture<List<Throwable>>, CompletableFuture<List<Throwable>>> finalActivityGenerator() {
-        return (e, t) -> t.thenApplyAsync(Function.identity(), e);
-    }
-
-    @Override
-    public BiFunction<Executor, ? extends EventGenerator<?>, CompletableFuture<List<Throwable>>> preDispatchHook() {
-        return (t, f)-> CompletableFuture.completedFuture(Collections.emptyList());
-    }
-
-    @Override
-    public BiFunction<Executor, ? extends EventGenerator<?>, CompletableFuture<List<Throwable>>> postDispatchHook() {
-        return (t, f)-> CompletableFuture.completedFuture(Collections.emptyList());
-    }
-}

fmlcore/src/main/java/net/minecraftforge/fml/ISystemReportExtender.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
@@ -24,4 +10,9 @@ import java.util.function.Supplier;
 public interface ISystemReportExtender extends Supplier<String>
 {
     String getLabel();
+
+    default boolean isActive()
+    {
+        return true;
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/InterModComms.java

@@ -1,81 +1,24 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-
 import java.util.Iterator;
 import java.util.Spliterator;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentLinkedQueue;
-import java.util.concurrent.ConcurrentMap;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
-public class InterModComms
-{
-    public record IMCMessage(String senderModId, String modId, String method, Supplier<?> messageSupplier) {
+public final class InterModComms {
+    public record IMCMessage(String senderModId, String modId, String method, Supplier<?> messageSupplier) {}
 
-        /**
-         * Deprecated: use {@link #senderModId()}
-         * @return The modid of the sender. This is supplied by the caller, or by the active mod container context.
-         * Consider it unreliable.
-         */
-        @Deprecated
-        public final String getSenderModId() {
-            return this.senderModId;
-        }
-
-        /**
-         * Deprecated: use {@link #modId()}
-         * @return The modid being sent to.
-         */
-        @Deprecated
-        public final String getModId() {
-            return this.modId;
-        }
-
-        /**
-         * Deprecated: use {@link #method()}
-         * @return The method being sent to.
-         */
-        @Deprecated
-        public final String getMethod() {
-            return this.method;
-        }
-
-        /**
-         * @param <T> The type of the message.
-         * @return A {@link Supplier} of the message.
-         * Use {@link #messageSupplier()}
-         */
-        @SuppressWarnings("unchecked")
-        @Deprecated
-        public final <T> Supplier<T> getMessageSupplier() {
-            return (Supplier<T>) this.messageSupplier;
-        }
-    }
-
-    private static ConcurrentMap<String, ConcurrentLinkedQueue<IMCMessage>> containerQueues = new ConcurrentHashMap<>();
+    private static final ConcurrentHashMap<String, ConcurrentLinkedQueue<IMCMessage>> containerQueues = new ConcurrentHashMap<>();
 
     /**
      * Send IMC to remote. Sender will default to the active modcontainer, or minecraft if not.
@@ -86,8 +29,9 @@ public class InterModComms
      * @return true if the message was enqueued for sending (the target modid is loaded)
      */
     public static boolean sendTo(final String modId, final String method, final Supplier<?> thing) {
-        if (!ModList.get().isLoaded(modId)) return false;
-        containerQueues.computeIfAbsent(modId, k->new ConcurrentLinkedQueue<>()).add(new IMCMessage(ModLoadingContext.get().getActiveContainer().getModId(), modId, method, thing));
+        if (!ModList.isLoaded(modId)) return false;
+        containerQueues.computeIfAbsent(modId, _ -> new ConcurrentLinkedQueue<>())
+                .add(new IMCMessage(ModLoadingContext.get().getContainer().getModId(), modId, method, thing));
         return true;
     }
 
@@ -101,8 +45,9 @@ public class InterModComms
      * @return true if the message was enqueued for sending (the target modid is loaded)
      */
     public static boolean sendTo(final String senderModId, final String modId, final String method, final Supplier<?> thing) {
-        if (!ModList.get().isLoaded(modId)) return false;
-        containerQueues.computeIfAbsent(modId, k->new ConcurrentLinkedQueue<>()).add(new IMCMessage(senderModId, modId, method, thing));
+        if (!ModList.isLoaded(modId)) return false;
+        containerQueues.computeIfAbsent(modId, _ -> new ConcurrentLinkedQueue<>())
+                .add(new IMCMessage(senderModId, modId, method, thing));
         return true;
     }
 
@@ -126,19 +71,17 @@ public class InterModComms
      * @return All messages
      */
     public static Stream<IMCMessage> getMessages(final String modId) {
-        return getMessages(modId, s->Boolean.TRUE);
+        return getMessages(modId, _ -> true);
     }
 
-    private static class QueueFilteringSpliterator implements Spliterator<IMCMessage>
-    {
-        private final ConcurrentLinkedQueue<IMCMessage> queue;
-        private final Predicate<String> methodFilter;
-        private final Iterator<IMCMessage> iterator;
+    private record QueueFilteringSpliterator(
+            ConcurrentLinkedQueue<IMCMessage> queue,
+            Predicate<String> methodFilter,
+            Iterator<IMCMessage> iterator
+    ) implements Spliterator<IMCMessage> {
 
         public QueueFilteringSpliterator(final ConcurrentLinkedQueue<IMCMessage> queue, final Predicate<String> methodFilter) {
-            this.queue = queue;
-            this.iterator = queue.iterator();
-            this.methodFilter = methodFilter;
+            this(queue, methodFilter, queue.iterator());
         }
 
         @Override
@@ -152,13 +95,10 @@ public class InterModComms
         }
 
         @Override
-        public boolean tryAdvance(final Consumer<? super IMCMessage> action)
-        {
+        public boolean tryAdvance(final Consumer<? super IMCMessage> action) {
             IMCMessage next;
-            do
-            {
-                if (!iterator.hasNext())
-                {
+            do {
+                if (!iterator.hasNext()) {
                     return false;
                 }
                 next = this.iterator.next();
@@ -173,6 +113,5 @@ public class InterModComms
         public Spliterator<IMCMessage> trySplit() {
             return null;
         }
-
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/LoadingFailedException.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;

fmlcore/src/main/java/net/minecraftforge/fml/Logging.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;

fmlcore/src/main/java/net/minecraftforge/fml/LogicalSide.java

@@ -1,41 +1,54 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-public enum LogicalSide
-{
-    CLIENT, SERVER;
+import net.minecraftforge.api.distmarker.Dist;
+
+/**
+ * A logical side of the Minecraft game.
+ * <p>
+ * The {@linkplain Dist#CLIENT client distribution} has a copy of the logical client and the logical server, while the
+ * {@linkplain Dist#DEDICATED_SERVER dedicated server distribution} only holds
+ * the logical server.
+ *
+ * @see Dist
+ */
+public enum LogicalSide {
+    /**
+     * The logical client of the Minecraft game, which interfaces with the player's inputs and renders the player's
+     * viewpoint.
+     * <p>
+     * The logical client is only shipped with the client distribution of the game.
+     *
+     * @see Dist#CLIENT
+     */
+    CLIENT,
 
     /**
-     * @return if the logical side is a server.
+     * The logical server of the Minecraft game, responsible for connecting to clients and running the simulation logic
+     * on the level.
+     * <p>
+     * The logical server is shipped with both client and dedicated server distributions. The client distribution runs
+     * the logical server for singleplayer mode and LAN play.
+     *
+     * @see Dist#DEDICATED_SERVER
      */
-    public boolean isServer()
-    {
+    SERVER;
+
+    /**
+     * {@return if this logical side is the server}
+     */
+    public boolean isServer() {
         return !isClient();
     }
 
     /**
-     * @return if the logical side is a client.
+     * {@return if the logical side is the client}
      */
-    public boolean isClient()
-    {
+    public boolean isClient() {
         return this == CLIENT;
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModContainer.java

@@ -1,40 +1,24 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.Event;
+import net.minecraftforge.eventbus.api.bus.BusGroup;
 import net.minecraftforge.fml.config.IConfigEvent;
 import net.minecraftforge.fml.config.ModConfig;
 import net.minecraftforge.fml.event.IModBusEvent;
 import net.minecraftforge.forgespi.language.IModInfo;
 
 import java.util.EnumMap;
-import java.util.HashMap;
+import java.util.HashSet;
 import java.util.IdentityHashMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.Executor;
-import java.util.function.BiFunction;
-import java.util.function.Consumer;
+import java.util.Set;
+import java.util.function.BiPredicate;
 import java.util.function.Supplier;
 
 /**
@@ -45,89 +29,77 @@ import java.util.function.Supplier;
  * a mechanism by which we can wrap actual mod code so that the loader and other
  * facilities can treat mods at arms length.
  * </p>
- *
- * @author cpw
- *
  */
-
-public abstract class ModContainer
-{
+public abstract class ModContainer {
     protected final String modId;
     protected final String namespace;
     protected final IModInfo modInfo;
     protected ModLoadingStage modLoadingStage;
     protected Supplier<?> contextExtension;
-    protected final Map<ModLoadingStage, Runnable> activityMap = new HashMap<>();
+    protected final Map<ModLoadingStage, Runnable> activityMap = new EnumMap<>(ModLoadingStage.class);
     protected final Map<Class<? extends IExtensionPoint<?>>, Supplier<?>> extensionPoints = new IdentityHashMap<>();
     protected final EnumMap<ModConfig.Type, ModConfig> configs = new EnumMap<>(ModConfig.Type.class);
-    @SuppressWarnings("OptionalUsedAsFieldOrParameterType")
-    protected Optional<Consumer<IConfigEvent>> configHandler = Optional.empty();
+    final Set<ModContainer> dependencies = new HashSet<>();
 
-    public ModContainer(IModInfo info)
-    {
+    public ModContainer(IModInfo info) {
         this.modId = info.getModId();
         // TODO: Currently not reading namespace from configuration..
         this.namespace = this.modId;
         this.modInfo = info;
         this.modLoadingStage = ModLoadingStage.CONSTRUCT;
-        // default displaytest extension checks for version string match
-        registerExtensionPoint(IExtensionPoint.DisplayTest.class, () -> new IExtensionPoint.DisplayTest(()->this.modInfo.getVersion().toString(),
-                (incoming, isNetwork)->Objects.equals(incoming, this.modInfo.getVersion().toString())));
+
+        final String displayTestString = info.getConfig().<String>getConfigElement("displayTest")
+                .orElseGet(() -> info.getOwningFile().isClientSideOnly() ? "IGNORE_ALL_VERSION" : "MATCH_VERSION");
+        Supplier<IExtensionPoint.DisplayTest> displayTestSupplier = switch (displayTestString) {
+            case "MATCH_VERSION" -> // default displaytest checks for version string match
+                    () -> new IExtensionPoint.DisplayTest(() -> this.modInfo.getVersion().toString(),
+                        (incoming, isNetwork) -> Objects.equals(incoming, this.modInfo.getVersion().toString()));
+            case "IGNORE_SERVER_VERSION" -> // Ignores any version information coming from the server - use for server only mods
+                    IExtensionPoint.DisplayTest.IGNORE_SERVER_VERSION;
+            case "IGNORE_ALL_VERSION" -> // Ignores all information and provides no information
+                    IExtensionPoint.DisplayTest.IGNORE_ALL_VERSION;
+            case "NONE" -> null; // NO display test at all - use this if you're going to do your own display test
+            default -> // any other value throws an exception
+                    throw new IllegalArgumentException("Invalid displayTest value supplied in mods.toml");
+        };
+        if (displayTestSupplier != null)
+            registerExtensionPoint(IExtensionPoint.DisplayTest.class, displayTestSupplier);
+        else
+            extensionPoints.remove(IExtensionPoint.DisplayTest.class);
     }
 
     /**
      * Errored container state, used for filtering. Does nothing.
      */
-    ModContainer()
-    {
+    ModContainer() {
         this.modLoadingStage = ModLoadingStage.ERROR;
         modId = "BROKEN";
         namespace = "BROKEN";
         modInfo = null;
     }
+
     /**
      * @return the modid for this mod
      */
-    public final String getModId()
-    {
+    public final String getModId() {
         return modId;
     }
 
     /**
      * @return the resource prefix for the mod
      */
-    public final String getNamespace()
-    {
+    public final String getNamespace() {
         return namespace;
     }
 
     /**
      * @return The current loading stage for this mod
      */
-    public ModLoadingStage getCurrentState()
-    {
+    public ModLoadingStage getCurrentState() {
         return modLoadingStage;
     }
 
-    public static <T extends Event & IModBusEvent> CompletableFuture<Void> buildTransitionHandler(
-            final ModContainer target,
-            final IModStateTransition.EventGenerator<T> eventGenerator,
-            final BiFunction<ModLoadingStage, Throwable, ModLoadingStage> stateChangeHandler,
-            final Executor executor) {
-        return CompletableFuture
-                .runAsync(() -> {
-                    ModLoadingContext.get().setActiveContainer(target);
-                    target.activityMap.getOrDefault(target.modLoadingStage, ()->{}).run();
-                    target.acceptEvent(eventGenerator.apply(target));
-                }, executor)
-                .whenComplete((mc, exception) -> {
-                    target.modLoadingStage = stateChangeHandler.apply(target.modLoadingStage, exception);
-                    ModLoadingContext.get().setActiveContainer(null);
-                });
-    }
-
-    public IModInfo getModInfo()
-    {
+    public IModInfo getModInfo() {
         return modInfo;
     }
 
@@ -136,18 +108,31 @@ public abstract class ModContainer
         return Optional.ofNullable((T)extensionPoints.getOrDefault(point,()-> null).get());
     }
 
-    public <T extends Record & IExtensionPoint<T>> void registerExtensionPoint(Class<? extends IExtensionPoint<T>> point, Supplier<T> extension)
-    {
+    public <T extends Record & IExtensionPoint<T>> void registerExtensionPoint(Class<? extends IExtensionPoint<T>> point, Supplier<T> extension) {
         extensionPoints.put(point, extension);
     }
 
+    public void registerDisplayTest(IExtensionPoint.DisplayTest displayTest) {
+        registerExtensionPoint(IExtensionPoint.DisplayTest.class, () -> displayTest);
+    }
+
+    public void registerDisplayTest(Supplier<IExtensionPoint.DisplayTest> displayTest) {
+        registerExtensionPoint(IExtensionPoint.DisplayTest.class, displayTest);
+    }
+
+    public void registerDisplayTest(String version, BiPredicate<String, Boolean> remoteVersionTest) {
+        registerDisplayTest(new IExtensionPoint.DisplayTest(version, remoteVersionTest));
+    }
+
+    public void registerDisplayTest(Supplier<String> suppliedVersion, BiPredicate<String, Boolean> remoteVersionTest) {
+        registerDisplayTest(new IExtensionPoint.DisplayTest(suppliedVersion, remoteVersionTest));
+    }
+
     public void addConfig(final ModConfig modConfig) {
        configs.put(modConfig.getType(), modConfig);
     }
 
-    public void dispatchConfigEvent(IConfigEvent event) {
-        configHandler.ifPresent(configHandler->configHandler.accept(event));
-    }
+    public void dispatchConfigEvent(IConfigEvent event) {}
 
     /**
      * Does this mod match the supplied mod?
@@ -162,9 +147,17 @@ public abstract class ModContainer
      */
     public abstract Object getMod();
 
+    /**
+     * @return the mod bus group for this specific mod, or null if there is none.
+     *         Leave null if you use {@link BusGroup#DEFAULT} for your mod lifecycle events.
+     */
+    public BusGroup getModBusGroup() {
+        return null;
+    }
+
     /**
      * Accept an arbitrary event for processing by the mod. Probably posted to an event bus in the lower level container.
      * @param e Event to accept
      */
-    protected <T extends Event & IModBusEvent> void acceptEvent(T e) {}
+    protected <T extends IModBusEvent> void acceptEvent(T e) {}
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModList.java

@@ -1,53 +1,26 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.Event;
-import net.minecraftforge.fml.event.IModBusEvent;
+import net.minecraftforge.fml.loading.LoadingModList;
 import net.minecraftforge.forgespi.language.IModFileInfo;
 import net.minecraftforge.forgespi.language.IModInfo;
 import net.minecraftforge.forgespi.language.ModFileScanData;
 import net.minecraftforge.fml.loading.moddiscovery.ModFile;
 import net.minecraftforge.fml.loading.moddiscovery.ModFileInfo;
-import net.minecraftforge.fml.loading.moddiscovery.ModInfo;
 import net.minecraftforge.forgespi.locating.IModFile;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 
-import java.util.AbstractMap;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.CompletionException;
-import java.util.concurrent.CompletionStage;
-import java.util.concurrent.Executor;
-import java.util.concurrent.ForkJoinPool;
-import java.util.concurrent.ForkJoinWorkerThread;
 import java.util.function.BiConsumer;
-import java.util.function.BiFunction;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.stream.Collectors;
@@ -57,188 +30,131 @@ import java.util.stream.Stream;
  * Master list of all mods - game-side version. This is classloaded in the game scope and
  * can dispatch game level events as a result.
  */
-public class ModList
-{
-    private static Logger LOGGER = LogManager.getLogger();
-    private static ModList INSTANCE;
-    private final List<IModFileInfo> modFiles;
-    private final List<IModInfo> sortedList;
-    private final Map<String, ModFileInfo> fileById;
-    private List<ModContainer> mods;
-    private Map<String, ModContainer> indexedMods;
-    private List<ModFileScanData> modFileScanData;
+public final class ModList {
+    private ModList() {}
 
-    private ModList(final List<ModFile> modFiles, final List<ModInfo> sortedList)
-    {
-        this.modFiles = modFiles.stream().map(ModFile::getModFileInfo).map(ModFileInfo.class::cast).collect(Collectors.toList());
-        this.sortedList = sortedList.stream().
-                map(ModInfo.class::cast).
-                collect(Collectors.toList());
-        this.fileById = this.modFiles.stream().map(IModFileInfo::getMods).flatMap(Collection::stream).
-                map(ModInfo.class::cast).
-                collect(Collectors.toMap(ModInfo::getModId, ModInfo::getOwningFile));
-        CrashReportCallables.registerCrashCallable("Mod List", this::crashReport);
+    private static final List<IModFileInfo> MOD_FILES;
+    private static final List<IModInfo> SORTED_LIST;
+    private static final Map<String, IModFileInfo> FILE_BY_ID;
+    private static List<ModContainer> mods;
+    private static Map<String, ModContainer> indexedMods;
+    private static List<ModContainer> sortedContainers;
+
+    static {
+        var loadingModFiles = LoadingModList.getModFiles().stream().map(ModFileInfo::getFile).toList();
+        var loadingSortedList = LoadingModList.getMods();
+
+        var modFileInfos = MOD_FILES = loadingModFiles.stream().map(ModFile::getModFileInfo).toList();
+        SORTED_LIST = loadingSortedList.stream().map(IModInfo.class::cast).toList();
+        var byId = new HashMap<String, IModFileInfo>();
+        for (var file : modFileInfos) {
+            for (var mod : file.getMods())
+                byId.put(mod.getModId(), mod.getOwningFile());
+        }
+        FILE_BY_ID = Map.copyOf(byId);
+        CrashReportCallables.registerCrashCallable("Mod List", ModList::crashReport);
     }
 
-    private String getModContainerState(String modId) {
+    private static String getModContainerState(String modId) {
         return getModContainerById(modId).map(ModContainer::getCurrentState).map(Object::toString).orElse("NONE");
     }
 
-    private String fileToLine(IModFile mf) {
-        return String.format("%-50.50s|%-30.30s|%-30.30s|%-20.20s|%-10.10s|Manifest: %s", mf.getFileName(),
-                mf.getModInfos().get(0).getDisplayName(),
-                mf.getModInfos().get(0).getModId(),
-                mf.getModInfos().get(0).getVersion(),
-                getModContainerState(mf.getModInfos().get(0).getModId()),
+    private static String fileToLine(IModFile mf) {
+        var mainMod = mf.getModInfos().getFirst();
+        return String.format(Locale.ENGLISH, "%-50.50s|%-30.30s|%-30.30s|%-20.20s|%-10.10s|Manifest: %s", mf.getFileName(),
+                mainMod.getDisplayName(),
+                mainMod.getModId(),
+                mainMod.getVersion(),
+                getModContainerState(mainMod.getModId()),
                 ((ModFileInfo)mf.getModFileInfo()).getCodeSigningFingerprint().orElse("NOSIGNATURE"));
     }
-    private String crashReport() {
-        return "\n"+applyForEachModFile(this::fileToLine).collect(Collectors.joining("\n\t\t", "\t\t", ""));
+
+    private static String crashReport() {
+        return "\n" + applyForEachModFile(ModList::fileToLine).collect(Collectors.joining("\n\t\t", "\t\t", ""));
     }
 
-    public static ModList of(List<ModFile> modFiles, List<ModInfo> sortedList)
-    {
-        INSTANCE = new ModList(modFiles, sortedList);
-        return INSTANCE;
+    public static void init() {}
+
+    public static List<IModFileInfo> getModFiles() {
+        return MOD_FILES;
     }
 
-    public static ModList get() {
-        return INSTANCE;
+    public static IModFileInfo getModFileById(String modid) {
+        return FILE_BY_ID.get(modid);
     }
 
-    private static ForkJoinWorkerThread newForkJoinWorkerThread(ForkJoinPool pool) {
-        ForkJoinWorkerThread thread = ForkJoinPool.defaultForkJoinWorkerThreadFactory.newThread(pool);
-        thread.setName("modloading-worker-" + thread.getPoolIndex());
-        // The default sets it to the SystemClassloader, so copy the current one.
-        thread.setContextClassLoader(Thread.currentThread().getContextClassLoader());
-        return thread;
+    static void setLoadedMods(final List<ModContainer> modContainers) {
+        mods = modContainers;
+        sortedContainers = modContainers.stream().sorted(Comparator.comparingInt(c -> SORTED_LIST.indexOf(c.getModInfo()))).toList();
+        indexedMods = modContainers.stream().collect(Collectors.toUnmodifiableMap(ModContainer::getModId, Function.identity()));
     }
 
-    public List<IModFileInfo> getModFiles()
-    {
-        return modFiles;
-    }
-
-    public IModFileInfo getModFileById(String modid)
-    {
-        return this.fileById.get(modid);
-    }
-
-    <T extends Event & IModBusEvent> Function<Executor, CompletableFuture<List<Throwable>>> futureVisitor(
-            final IModStateTransition.EventGenerator<T> eventGenerator,
-            final BiFunction<ModLoadingStage, Throwable, ModLoadingStage> stateChange) {
-        return executor -> gather(
-                this.mods.stream()
-                .map(mod -> ModContainer.buildTransitionHandler(mod, eventGenerator, stateChange, executor))
-                .collect(Collectors.toList()))
-            .thenComposeAsync(ModList::completableFutureFromExceptionList, executor);
-    }
-    static CompletionStage<List<Throwable>> completableFutureFromExceptionList(List<? extends Map.Entry<?, Throwable>> t) {
-        if (t.stream().noneMatch(e->e.getValue()!=null)) {
-            return CompletableFuture.completedFuture(Collections.emptyList());
-        } else {
-            final List<Throwable> throwables = t.stream().filter(e -> e.getValue() != null).map(Map.Entry::getValue).collect(Collectors.toList());
-            CompletableFuture<List<Throwable>> cf = new CompletableFuture<>();
-            final RuntimeException accumulator = new RuntimeException();
-            cf.completeExceptionally(accumulator);
-            throwables.forEach(exception -> {
-                if (exception instanceof CompletionException) {
-                    exception = exception.getCause();
-                }
-                if (exception.getSuppressed().length!=0) {
-                    Arrays.stream(exception.getSuppressed()).forEach(accumulator::addSuppressed);
-                } else {
-                    accumulator.addSuppressed(exception);
-                }
-            });
-            return cf;
-        }
-    }
-
-    static <V> CompletableFuture<List<Map.Entry<V, Throwable>>> gather(List<? extends CompletableFuture<? extends V>> futures) {
-        List<Map.Entry<V, Throwable>> list = new ArrayList<>(futures.size());
-        CompletableFuture<?>[] results = new CompletableFuture[futures.size()];
-        futures.forEach(future -> {
-            int i = list.size();
-            list.add(null);
-            results[i] = future.whenComplete((result, exception) -> list.set(i, new AbstractMap.SimpleImmutableEntry<>(result, exception)));
-        });
-        return CompletableFuture.allOf(results).handle((r, th)->null).thenApply(res -> list);
-    }
-
-    void setLoadedMods(final List<ModContainer> modContainers)
-    {
-        this.mods = modContainers;
-        this.indexedMods = modContainers.stream().collect(Collectors.toMap(ModContainer::getModId, Function.identity()));
+    static void clearLoadedMods() {
+        mods = List.of();
+        indexedMods = Map.of();
+        sortedContainers = List.of();
     }
 
     @SuppressWarnings("unchecked")
-    public <T> Optional<T> getModObjectById(String modId)
-    {
+    public static <T> Optional<T> getModObjectById(String modId) {
         return getModContainerById(modId).map(ModContainer::getMod).map(o -> (T) o);
     }
 
-    public Optional<? extends ModContainer> getModContainerById(String modId)
-    {
-        return Optional.ofNullable(this.indexedMods.get(modId));
+    public static Optional<? extends ModContainer> getModContainerById(String modId) {
+        return Optional.ofNullable(indexedMods.get(modId));
     }
 
-    public Optional<? extends ModContainer> getModContainerByObject(Object obj)
-    {
+    public static Optional<? extends ModContainer> getModContainerByObject(Object obj) {
         return mods.stream().filter(mc -> mc.getMod() == obj).findFirst();
     }
 
-    public List<IModInfo> getMods()
-    {
-        return this.sortedList;
+    public static List<IModInfo> getMods() {
+        return SORTED_LIST;
     }
 
-    public boolean isLoaded(String modTarget)
-    {
-        return this.indexedMods.containsKey(modTarget);
+    public static boolean isLoaded(String modTarget) {
+        return indexedMods.containsKey(modTarget);
     }
 
-    public int size()
-    {
+    public static int size() {
         return mods.size();
     }
 
-    public List<ModFileScanData> getAllScanData()
-    {
-        if (modFileScanData == null)
-        {
-            modFileScanData = this.sortedList.stream().
-                    map(IModInfo::getOwningFile).
-                    filter(Objects::nonNull).
-                    map(IModFileInfo::getFile).
-                    distinct().
-                    map(IModFile::getScanResult).
-                    collect(Collectors.toList());
+    public static List<ModFileScanData> getAllScanData() {
+        final class LazyInit {
+            private LazyInit() {}
+            private static final List<ModFileScanData> MOD_FILE_SCAN_DATA = SORTED_LIST.stream()
+                    .map(IModInfo::getOwningFile)
+                    .filter(Objects::nonNull)
+                    .map(IModFileInfo::getFile)
+                    .distinct()
+                    .map(IModFile::getScanResult)
+                    .toList();
         }
-        return modFileScanData;
-
+        return LazyInit.MOD_FILE_SCAN_DATA;
     }
 
-    public void forEachModFile(Consumer<IModFile> fileConsumer)
-    {
-        modFiles.stream().map(IModFileInfo::getFile).forEach(fileConsumer);
+    public static void forEachModFile(Consumer<IModFile> fileConsumer) {
+        MOD_FILES.stream().map(IModFileInfo::getFile).forEach(fileConsumer);
     }
 
-    public <T> Stream<T> applyForEachModFile(Function<IModFile, T> function) {
-        return modFiles.stream().map(IModFileInfo::getFile).map(function);
+    public static <T> Stream<T> applyForEachModFile(Function<IModFile, T> function) {
+        return MOD_FILES.stream().map(IModFileInfo::getFile).map(function);
     }
 
-    public void forEachModContainer(BiConsumer<String, ModContainer> modContainerConsumer) {
+    public static void forEachModContainer(BiConsumer<String, ModContainer> modContainerConsumer) {
         indexedMods.forEach(modContainerConsumer);
     }
 
-    public <T> Stream<T> applyForEachModContainer(Function<ModContainer, T> function) {
-        return indexedMods.values().stream().map(function);
+    public static void forEachModInOrder(Consumer<ModContainer> containerConsumer) {
+        sortedContainers.forEach(containerConsumer);
     }
 
-    private static class UncaughtModLoadingException extends ModLoadingException {
-        public UncaughtModLoadingException(ModLoadingStage stage, Throwable originalException) {
-            super(null, stage, "fml.modloading.uncaughterror", originalException);
-        }
+    public static List<ModContainer> getLoadedMods() {
+        return sortedContainers;
+    }
+
+    public static <T> Stream<T> applyForEachModContainer(Function<ModContainer, T> function) {
+        return indexedMods.values().stream().map(function);
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModLoader.java

@@ -1,51 +1,32 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-import com.google.common.collect.ImmutableList;
-import net.minecraftforge.eventbus.api.Event;
+import net.minecraftforge.eventbus.api.bus.BusGroup;
 import net.minecraftforge.fml.event.IModBusEvent;
-import net.minecraftforge.fml.loading.FMLLoader;
-import net.minecraftforge.fml.loading.LoadingModList;
+import net.minecraftforge.fml.loading.*;
 import net.minecraftforge.fml.loading.moddiscovery.InvalidModIdentifier;
-import net.minecraftforge.fml.loading.moddiscovery.ModFile;
 import net.minecraftforge.fml.loading.moddiscovery.ModFileInfo;
-import net.minecraftforge.fml.loading.progress.StartupMessageManager;
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
 import net.minecraftforge.forgespi.language.IModInfo;
 import net.minecraftforge.forgespi.language.IModLanguageProvider;
+import net.minecraftforge.forgespi.locating.ForgeFeature;
+import net.minecraftforge.forgespi.locating.IModFile;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Optional;
+import java.util.*;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.Executor;
+import java.util.function.BiConsumer;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.stream.Collectors;
-
 import static net.minecraftforge.fml.Logging.CORE;
 import static net.minecraftforge.fml.Logging.LOADING;
 
@@ -85,190 +66,271 @@ import static net.minecraftforge.fml.Logging.LOADING;
  *     and completes the mod loading sequence.</dd>
  * </dl>
  */
-public class ModLoader
-{
+public final class ModLoader {
+    private ModLoader() {}
+
     private static final Logger LOGGER = LogManager.getLogger();
-    private static ModLoader INSTANCE;
-    private final LoadingModList loadingModList;
+    private static final ArrayList<ModLoadingException> LOADING_EXCEPTIONS = new ArrayList<>();
+    private static final ArrayList<ModLoadingWarning> LOADING_WARNINGS = new ArrayList<>();
+    private static final Consumer<String> STATUS_CONSUMER = StartupNotificationManager.modLoaderConsumer().orElse(_ -> {});
+    private static final HashSet<IModLoadingState> COMPLETED_STATES = new HashSet<>();
+    private static boolean loadingStateValid;
 
-    private final List<ModLoadingException> loadingExceptions;
-    private final List<ModLoadingWarning> loadingWarnings;
-    private final ModStateManager stateManager;
-    private boolean loadingStateValid;
-    @SuppressWarnings("OptionalUsedAsFieldOrParameterType")
-    private final Optional<Consumer<String>> statusConsumer = StartupMessageManager.modLoaderConsumer();
-    private ModList modList;
-
-    private ModLoader()
-    {
-        INSTANCE = this;
-        this.loadingModList = FMLLoader.getLoadingModList();
-        this.loadingExceptions = FMLLoader.getLoadingModList().getErrors().stream()
-                .flatMap(ModLoadingException::fromEarlyException)
-                .collect(Collectors.toList());
-        this.loadingWarnings = FMLLoader.getLoadingModList().getBrokenFiles().stream()
-                .map(file -> new ModLoadingWarning(null, ModLoadingStage.VALIDATE, InvalidModIdentifier.identifyJarProblem(file.getFilePath()).orElse("fml.modloading.brokenfile"), file.getFileName()))
-                .collect(Collectors.toList());
-        FMLLoader.getLoadingModList().getModFiles().stream()
-                .filter(ModFileInfo::missingLicense) //Search for files with missing licenses
-                .filter(modFileInfo -> modFileInfo.getMods().stream().noneMatch(thisModInfo -> this.loadingExceptions.stream().map(ModLoadingException::getModInfo).anyMatch(otherInfo -> otherInfo == thisModInfo))) //Ignore files where any other mod already encountered an error
-                .map(modFileInfo -> new ModLoadingException(null, ModLoadingStage.VALIDATE, "fml.modloading.missinglicense", null, modFileInfo.getFile()))
-                .forEach(this.loadingExceptions::add);
-        this.stateManager = new ModStateManager();
-        CrashReportCallables.registerCrashCallable("ModLauncher", FMLLoader::getLauncherInfo);
-        CrashReportCallables.registerCrashCallable("ModLauncher launch target", FMLLoader::launcherHandlerName);
-        CrashReportCallables.registerCrashCallable("ModLauncher naming", FMLLoader::getNaming);
-        CrashReportCallables.registerCrashCallable("ModLauncher services", this::computeModLauncherServiceList);
-        CrashReportCallables.registerCrashCallable("FML Language Providers", this::computeLanguageList);
+    private static String computeLanguageList() {
+        return "\n" + LanguageLoadingProvider
+                .applyForEach(lp -> lp.name() + '@' + lp.getClass().getPackage().getImplementationVersion())
+                .collect(Collectors.joining("\n\t\t", "\t\t", ""));
     }
 
-    private String computeLanguageList() {
-        return "\n"+FMLLoader.getLanguageLoadingProvider().applyForEach(lp->lp.name() +"@"+ lp.getClass().getPackage().getImplementationVersion()).collect(Collectors.joining("\n\t\t", "\t\t", ""));
-    }
-
-    private String computeModLauncherServiceList() {
+    private static String computeModLauncherServiceList() {
         final List<Map<String, String>> mods = FMLLoader.modLauncherModList();
-        return "\n"+mods.stream().map(mod->mod.getOrDefault("file","nofile")+
-                " "+mod.getOrDefault("name", "missing")+
-                " "+mod.getOrDefault("type","NOTYPE")+
-                " "+mod.getOrDefault("description", "")).
+        return "\n" + mods.stream().map(mod -> mod.getOrDefault("file","nofile") +
+                ' ' + mod.getOrDefault("name", "missing") +
+                ' ' + mod.getOrDefault("type","NOTYPE") +
+                ' ' + mod.getOrDefault("description", "")).
                 collect(Collectors.joining("\n\t\t","\t\t",""));
     }
 
-    public static ModLoader get()
-    {
-        return INSTANCE == null ? INSTANCE = new ModLoader() : INSTANCE;
-    }
-
     /**
      * Run on the primary starting thread by ClientModLoader and ServerModLoader
      * @param syncExecutor An executor to run tasks on the main thread
      * @param parallelExecutor An executor to run tasks on a parallel loading thread pool
      * @param periodicTask Optional periodic task to perform on the main thread while other activities run
      */
-    public void gatherAndInitializeMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
-        loadingStateValid = true;
-        statusConsumer.ifPresent(c->c.accept("Waiting for scan to complete"));
-        FMLLoader.backgroundScanHandler.waitForScanToComplete(periodicTask);
-        statusConsumer.ifPresent(c->c.accept("Loading mods"));
-        final ModList modList = ModList.of(loadingModList.getModFiles().stream().map(ModFileInfo::getFile).toList(),
-                loadingModList.getMods());
-        if (!this.loadingExceptions.isEmpty()) {
-            LOGGER.fatal(CORE, "Error during pre-loading phase", loadingExceptions.get(0));
-            modList.setLoadedMods(Collections.emptyList());
-            loadingStateValid = false;
-            throw new LoadingFailedException(loadingExceptions);
-        }
-        statusConsumer.ifPresent(c->c.accept("Building Mod List"));
-        final List<ModContainer> modContainers = loadingModList.getModFiles().stream()
-                .map(ModFileInfo::getFile)
-                .map(this::buildMods)
-                .<ModContainer>mapMulti(Iterable::forEach)
+    public static void gatherAndInitializeMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
+        var loadingExceptions = LoadingModList.getErrors().stream()
+                .flatMap(ModLoadingException::fromEarlyException)
                 .toList();
-        if (!loadingExceptions.isEmpty()) {
-            LOGGER.fatal(CORE, "Failed to initialize mod containers", loadingExceptions.get(0));
-            modList.setLoadedMods(Collections.emptyList());
+        ModLoader.LOADING_EXCEPTIONS.addAll(loadingExceptions);
+        LOADING_WARNINGS.addAll(LoadingModList.getBrokenFiles().stream()
+                .map(file -> new ModLoadingWarning(null, ModLoadingStage.VALIDATE, InvalidModIdentifier.identifyJarProblem(file.getFilePath()).orElse("fml.modloading.brokenfile"), file.getFileName()))
+                .toList());
+        Set<IModInfo> erroredModInfos;
+        if (loadingExceptions.isEmpty()) {
+            erroredModInfos = Collections.emptySet();
+        } else {
+            erroredModInfos = Collections.newSetFromMap(new IdentityHashMap<>());
+            erroredModInfos.addAll(loadingExceptions.stream().map(ModLoadingException::getModInfo).toList());
+        }
+        LoadingModList.getModFiles().stream()
+                .filter(ModFileInfo::missingLicense)
+                .filter(modFileInfo -> modFileInfo.getMods().stream().noneMatch(erroredModInfos::contains)) //Ignore files where any other mod already encountered an error
+                .map(modFileInfo -> new ModLoadingException(null, ModLoadingStage.VALIDATE, "fml.modloading.missinglicense", null, modFileInfo.getFile()))
+                .forEach(LOADING_EXCEPTIONS::add);
+        CrashReportCallables.registerCrashCallable("ModLauncher", FMLLoader::getLauncherInfo);
+        CrashReportCallables.registerCrashCallable("ModLauncher launch target", FMLLoader::launcherHandlerName);
+        CrashReportCallables.registerCrashCallable("ModLauncher naming", FMLLoader::getNaming);
+        CrashReportCallables.registerCrashCallable("ModLauncher services", ModLoader::computeModLauncherServiceList);
+        CrashReportCallables.registerCrashCallable("FML Language Providers", ModLoader::computeLanguageList);
+
+        ForgeFeature.registerFeature("javaVersion", ForgeFeature.VersionFeatureTest.forVersionString(IModInfo.DependencySide.BOTH, System.getProperty("java.version")));
+        ForgeFeature.registerFeature("openGLVersion", ForgeFeature.VersionFeatureTest.forVersionString(IModInfo.DependencySide.CLIENT, ImmediateWindowHandler.getGLVersion()));
+        loadingStateValid = true;
+        FMLLoader.backgroundScanHandler.waitForScanToComplete(periodicTask);
+        if (!LOADING_EXCEPTIONS.isEmpty()) {
+            LOGGER.fatal(CORE, "Error during pre-loading phase", LOADING_EXCEPTIONS.getFirst());
+            STATUS_CONSUMER.accept("ERROR DURING MOD LOADING");
+            ModList.clearLoadedMods();
             loadingStateValid = false;
-            throw new LoadingFailedException(loadingExceptions);
+            throw new LoadingFailedException(LOADING_EXCEPTIONS);
         }
-        modList.setLoadedMods(modContainers);
-        this.modList = modList;
-        statusConsumer.ifPresent(c->c.accept("Dispatching gathering events"));
-        stateManager.getStates(ModLoadingPhase.GATHER).forEach(mls->dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask));
-        statusConsumer.ifPresent(c->c.accept("Gathering phase complete"));
+        var failedBounds = new ArrayList<ForgeFeature.Bound>();
+        for (var mod : LoadingModList.getMods()) {
+            for (var feature : mod.getForgeFeatures()) {
+                if (!ForgeFeature.testFeature(FMLEnvironment.dist, feature))
+                    failedBounds.add(feature);
+            }
+        }
+
+        if (!failedBounds.isEmpty()) {
+            LOGGER.fatal(CORE, "Failed to validate feature bounds for mods: {}", failedBounds);
+            STATUS_CONSUMER.accept("ERROR DURING MOD LOADING");
+            ModList.clearLoadedMods();
+            loadingStateValid = false;
+            throw new LoadingFailedException(failedBounds.stream()
+                    .map(fb -> new ModLoadingException(fb.modInfo(), ModLoadingStage.CONSTRUCT, "fml.modloading.feature.missing", null, fb, ForgeFeature.featureValue(fb)))
+                    .toList());
+        }
+
+        final var modContainers = new HashMap<String, ModContainer>();
+        for (var file : LoadingModList.getModFiles()) {
+            var containers = buildMods(file.getFile());
+            for (var container : containers)
+                modContainers.put(container.getModId(), container);
+        }
+
+        if (!LOADING_EXCEPTIONS.isEmpty()) {
+            LOGGER.fatal(CORE, "Failed to initialize mod containers", LOADING_EXCEPTIONS.getFirst());
+            STATUS_CONSUMER.accept("ERROR DURING MOD LOADING");
+            ModList.clearLoadedMods();
+            loadingStateValid = false;
+            throw new LoadingFailedException(LOADING_EXCEPTIONS);
+        }
+
+        // Gather all dependencies, so we can make sure they have finished their transition events before we fire ours
+        for (var mod : modContainers.values()) {
+            for (var dep : mod.getModInfo().getDependencies()) {
+                var target = modContainers.get(dep.getModId());
+                if (target == null)
+                    continue;
+
+                switch (dep.getOrdering()) {
+                    case AFTER:
+                        mod.dependencies.add(target);
+                        break;
+                    case BEFORE:
+                        target.dependencies.add(mod);
+                        break;
+                    default:
+                        break;
+                }
+            }
+        }
+
+        ModList.setLoadedMods(modContainers.values().stream().toList());
+        var stateList = ModStateManager.getStates(ModLoadingPhase.GATHER);
+        var progress = StartupMessageManager.addProgressBar("Mod Gather", stateList.stream().mapToInt(mls -> mls.size().getAsInt()).sum());
+        for (IModLoadingState mls : stateList) {
+            dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask, progress);
+        }
+        progress.complete();
     }
 
-    public void loadMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
-        statusConsumer.ifPresent(c->c.accept("Performing load phase"));
-        stateManager.getStates(ModLoadingPhase.LOAD).forEach(mls->dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask));
-        statusConsumer.ifPresent(c->c.accept("Mod setup complete"));
+    public static void loadMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
+        var stateList = ModStateManager.getStates(ModLoadingPhase.LOAD);
+        var progress = StartupMessageManager.addProgressBar("Mod Loading", stateList.stream().mapToInt(mls -> mls.size().getAsInt()).sum());
+        for (IModLoadingState mls : stateList) {
+            dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask, progress);
+        }
+        progress.complete();
     }
 
-    public void finishMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
-        statusConsumer.ifPresent(c->c.accept("Performing completion phase"));
-        stateManager.getStates(ModLoadingPhase.COMPLETE).forEach(mls->dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask));
-        statusConsumer.ifPresent(c->c.accept(String.format("Mod loading complete - %d mods loaded", this.modList.size())));
+    public static void finishMods(final ModWorkManager.DrivenExecutor syncExecutor, final Executor parallelExecutor, final Runnable periodicTask) {
+        var stateList = ModStateManager.getStates(ModLoadingPhase.COMPLETE);
+        var progress = StartupMessageManager.addProgressBar("Mod Complete", stateList.stream().mapToInt(mls -> mls.size().getAsInt()).sum());
+        for (IModLoadingState mls : stateList) {
+            dispatchAndHandleError(mls, syncExecutor, parallelExecutor, periodicTask, progress);
+        }
+
+        var modBusGroups = Set.of(
+                ModList.getLoadedMods().stream()
+                        .map(ModContainer::getModBusGroup)
+                        .filter(Objects::nonNull)
+                        .toArray(BusGroup[]::new)
+        );
+        for (var modBusGroup : modBusGroups) {
+            parallelExecutor.execute(modBusGroup::trim);
+        }
+        parallelExecutor.execute(BusGroup.DEFAULT::trim);
+
+        STATUS_CONSUMER.accept("Mod loading complete - %d mods loaded".formatted(ModList.size()));
+        progress.complete();
     }
 
-    private void dispatchAndHandleError(IModLoadingState state, ModWorkManager.DrivenExecutor syncExecutor, Executor parallelExecutor, final Runnable ticker) {
+    private static void dispatchAndHandleError(IModLoadingState state, ModWorkManager.DrivenExecutor syncExecutor, Executor parallelExecutor, final Runnable ticker, final ProgressMeter progressBar) {
         if (!isLoadingStateValid()) {
             LOGGER.error("Cowardly refusing to process mod state change request from {}", state);
             return;
         }
-        statusConsumer.ifPresent(c->c.accept(state.message().apply(this.modList)));
-        state.inlineRunnable().ifPresent(a->a.accept(this.modList));
-        state.buildTransition(syncExecutor, parallelExecutor).ifPresent(t->waitForTransition(state, syncExecutor, ticker, t));
+        progressBar.label(progressBar.name() + " working");
+        syncExecutor.drive(ticker);
+
+        var inlineRunnable = state.inlineRunnable();
+        if (inlineRunnable != null) handleInlineTransition(inlineRunnable, state, syncExecutor, ticker);
+
+        var transition = state.buildTransition(syncExecutor, parallelExecutor, progressBar);
+        if (transition != null) waitForTransition(state, syncExecutor, ticker, transition);
+
+        COMPLETED_STATES.add(state);
     }
 
-    private void dispatchAndHandleError(IModLoadingState state, ModWorkManager.DrivenExecutor syncExecutor, Executor parallelExecutor, final Runnable ticker, Function<Executor, CompletableFuture<Void>> preSyncTask, Function<Executor, CompletableFuture<Void>> postSyncTask) {
-        if (!isLoadingStateValid()) {
-            LOGGER.error("Cowardly refusing to process mod state change request from {}", state);
-            return;
-        }
-        statusConsumer.ifPresent(c->c.accept(state.message().apply(this.modList)));
-        state.inlineRunnable().ifPresent(a->a.accept(this.modList));
-        state.buildTransition(syncExecutor, parallelExecutor, preSyncTask, postSyncTask).ifPresent(t->waitForTransition(state, syncExecutor, ticker, t));
+    private static void handleInlineTransition(final Runnable transition, final IModLoadingState state, final ModWorkManager.DrivenExecutor syncExecutor, final Runnable ticker) {
+        var pb = StartupMessageManager.addProgressBar("State transition " + state.name() + " running", 0);
+        syncExecutor.drive(ticker);
+        transition.run();
+        syncExecutor.drive(ticker);
+        pb.complete();
+        syncExecutor.drive(ticker);
     }
 
-    private void waitForTransition(final IModLoadingState state, final ModWorkManager.DrivenExecutor syncExecutor, final Runnable ticker, final CompletableFuture<List<Throwable>> transition) {
+    private static void waitForTransition(final IModLoadingState state, final ModWorkManager.DrivenExecutor syncExecutor, final Runnable ticker, final CompletableFuture<Void> transition) {
         while (!transition.isDone()) {
             syncExecutor.drive(ticker);
         }
+
         try {
             transition.join();
         } catch (CompletionException e) {
             loadingStateValid = false;
             Throwable t = e.getCause();
-            final List<Throwable> notModLoading = Arrays.stream(t.getSuppressed())
-                    .filter(obj -> !(obj instanceof ModLoadingException))
-                    .collect(Collectors.toList());
-            if (!notModLoading.isEmpty()) {
+            boolean hasNotModLoadingEx = Arrays.stream(t.getSuppressed())
+                    .anyMatch(obj -> !(obj instanceof ModLoadingException));
+            if (hasNotModLoadingEx) {
                 LOGGER.fatal("Encountered non-modloading exceptions!", e);
+                STATUS_CONSUMER.accept("ERROR DURING MOD LOADING");
                 throw e;
             }
 
             final List<ModLoadingException> modLoadingExceptions = Arrays.stream(t.getSuppressed())
                     .filter(ModLoadingException.class::isInstance)
                     .map(ModLoadingException.class::cast)
-                    .collect(Collectors.toList());
+                    .toList();
             LOGGER.fatal(LOADING,"Failed to complete lifecycle event {}, {} errors found", state.name(), modLoadingExceptions.size());
+            STATUS_CONSUMER.accept("ERROR DURING MOD LOADING");
             throw new LoadingFailedException(modLoadingExceptions);
         }
     }
 
-    private List<ModContainer> buildMods(final ModFile modFile)
-    {
-        final Map<String, IModInfo> modInfoMap = modFile.getModFileInfo().getMods().stream().collect(Collectors.toMap(IModInfo::getModId, Function.identity()));
+    private static List<ModContainer> buildMods(final IModFile modFile) {
+        final Map<String, IModInfo> modInfoMap = new HashMap<>();
+        for (var mod : modFile.getModFileInfo().getMods())
+            modInfoMap.put(mod.getModId(), mod);
 
         LOGGER.trace(LOADING, "ModContainer is {}", ModContainer.class.getClassLoader());
-        final List<ModContainer> containers = modFile.getScanResult().getTargets()
-                .entrySet()
-                .stream()
-                .map(e -> buildModContainerFromTOML(modFile, modInfoMap, e))
-                .filter(Objects::nonNull)
-                .collect(Collectors.toList());
-        if (containers.size() != modInfoMap.size()) {
-            LOGGER.fatal(LOADING,"File {} constructed {} mods: {}, but had {} mods specified: {}",
-                    modFile.getFilePath(),
-                    containers.size(), containers.stream().map(c -> c != null ? c.getModId() : "(null)").sorted().collect(Collectors.toList()),
-                    modInfoMap.size(), modInfoMap.values().stream().map(IModInfo::getModId).sorted().collect(Collectors.toList()));
-            loadingExceptions.add(new ModLoadingException(null, ModLoadingStage.CONSTRUCT, "fml.modloading.missingclasses", null, modFile.getFilePath()));
+        final List<ModContainer> containers = new ArrayList<>();
+        for (var entry : modFile.getScanResult().getTargets().entrySet()) {
+            var container = buildModContainerFromTOML(modFile, modInfoMap, entry.getKey(), entry.getValue());
+            if (container != null)
+                containers.add(container);
         }
+
+        if (containers.size() != modInfoMap.size()) {
+            var modIds = modInfoMap.values().stream().map(IModInfo::getModId).sorted().toList();
+            var containerIds = containers.stream().map(c -> c != null ? c.getModId() : "(null)").sorted().toList();
+
+            LOGGER.fatal(LOADING, "File {} constructed {} mods: {}, but had {} mods specified: {}",
+                    modFile.getFilePath(),
+                    containers.size(), containerIds,
+                    modInfoMap.size(), modIds);
+
+            var missingClasses = new ArrayList<>(modIds);
+            missingClasses.removeAll(containerIds);
+            LOGGER.fatal(LOADING, "The following classes are missing, but are reported in the mods.toml: {}", missingClasses);
+
+            var missingMods = new ArrayList<>(containerIds);
+            missingMods.removeAll(modIds);
+            LOGGER.fatal(LOADING, "The following mods are missing, but have classes in the jar: {}", missingMods);
+
+            LOADING_EXCEPTIONS.add(new ModLoadingException(null, ModLoadingStage.CONSTRUCT, "fml.modloading.missingclasses", null, modFile.getFilePath()));
+        }
+
         // remove errored mod containers
-        return containers.stream().filter(mc -> mc.modLoadingStage != ModLoadingStage.ERROR).collect(Collectors.toList());
+        return containers.stream().filter(mc -> mc.modLoadingStage != ModLoadingStage.ERROR).toList();
     }
 
-    private ModContainer buildModContainerFromTOML(final ModFile modFile, final Map<String, IModInfo> modInfoMap, final Map.Entry<String, ? extends IModLanguageProvider.IModLanguageLoader> idToProviderEntry) {
+    private static ModContainer buildModContainerFromTOML(final IModFile modFile, final Map<String, IModInfo> modInfoMap,
+        final String modId, final IModLanguageProvider.IModLanguageLoader languageLoader
+    ) {
         try {
-            final String modId = idToProviderEntry.getKey();
-            final IModLanguageProvider.IModLanguageLoader languageLoader = idToProviderEntry.getValue();
-            IModInfo info = Optional.ofNullable(modInfoMap.get(modId)).
-                    // throw a missing metadata error if there is no matching modid in the modInfoMap from the mods.toml file
-                    orElseThrow(()->new ModLoadingException(null, ModLoadingStage.CONSTRUCT, "fml.modloading.missingmetadata", null, modId));
+            IModInfo info = modInfoMap.get(modId);
+            // throw a missing metadata error if there is no matching modid in the modInfoMap from the mods.toml file
+            if (info == null)
+                throw new ModLoadingException(null, ModLoadingStage.CONSTRUCT, "fml.modloading.missingmetadata", null, modId);
+
             return languageLoader.loadMod(info, modFile.getScanResult(), FMLLoader.getGameLayer());
         } catch (ModLoadingException mle) {
             // exceptions are caught and added to the error list for later handling
-            loadingExceptions.add(mle);
+            LOADING_EXCEPTIONS.add(mle);
             // return an errored container instance here, because we tried and failed building a container.
             return new ErroredModContainer();
         }
@@ -279,33 +341,67 @@ public class ModLoader
      * and don't want to cause extraneous crashes due to trying to do things that aren't possible in a "broken load"
      */
     public static boolean isLoadingStateValid() {
-        return get().loadingStateValid;
+        return loadingStateValid;
     }
 
-    public <T extends Event & IModBusEvent> void runEventGenerator(Function<ModContainer, T> generator) {
+    public static boolean hasCompletedState(IModLoadingState state) {
+        return COMPLETED_STATES.contains(state);
+    }
+
+    public static <T extends IModBusEvent> void runEventGenerator(Function<ModContainer, T> generator) {
         if (!loadingStateValid) {
             LOGGER.error("Cowardly refusing to send event generator to a broken mod state");
             return;
         }
-        ModList.get().forEachModContainer((id, mc) -> mc.acceptEvent(generator.apply(mc)));
+        for (var mod : ModList.getLoadedMods())
+            mod.acceptEvent(generator.apply(mod));
     }
 
-    public <T extends Event & IModBusEvent> void postEvent(T e) {
+    public static <T extends IModBusEvent> void postEvent(T e) {
         if (!loadingStateValid) {
             LOGGER.error("Cowardly refusing to send event {} to a broken mod state", e.getClass().getName());
             return;
         }
-        ModList.get().forEachModContainer((id, mc) -> mc.acceptEvent(e));
+        for (var mod : ModList.getLoadedMods())
+            mod.acceptEvent(e);
     }
 
-    public List<ModLoadingWarning> getWarnings()
-    {
-        return ImmutableList.copyOf(this.loadingWarnings);
+    public static <T extends IModBusEvent> T postEventWithReturn(T e) {
+        if (!loadingStateValid) {
+            LOGGER.error("Cowardly refusing to send event {} to a broken mod state", e.getClass().getName());
+            return e;
+        }
+        for (var mod : ModList.getLoadedMods())
+            mod.acceptEvent(e);
+        return e;
     }
 
-    public void addWarning(ModLoadingWarning warning)
-    {
-        this.loadingWarnings.add(warning);
+    @SuppressWarnings("removal")
+    public static <T extends IModBusEvent> void postEventWrapContainerInModOrder(T event) {
+        postEventWithWrapInModOrder(event,
+            (mc, e) -> ModLoadingContext.get().setActiveContainer(mc),
+            (mc, e) -> ModLoadingContext.get().setActiveContainer(null)
+        );
+    }
+
+    public static <T extends IModBusEvent> void postEventWithWrapInModOrder(T e, BiConsumer<ModContainer, T> pre, BiConsumer<ModContainer, T> post) {
+        if (!loadingStateValid) {
+            LOGGER.error("Cowardly refusing to send event {} to a broken mod state", e.getClass().getName());
+            return;
+        }
+        for (var mod : ModList.getLoadedMods()) {
+            pre.accept(mod, e);
+            mod.acceptEvent(e);
+            post.accept(mod, e);
+        }
+    }
+
+    public static List<ModLoadingWarning> getWarnings() {
+        return List.copyOf(LOADING_WARNINGS);
+    }
+
+    public static void addWarning(ModLoadingWarning warning) {
+        LOADING_WARNINGS.add(warning);
     }
 
     private static boolean runningDataGen = false;
@@ -314,7 +410,7 @@ public class ModLoader
         return runningDataGen;
     }
 
-    private static class ErroredModContainer extends ModContainer {
+    private static final class ErroredModContainer extends ModContainer {
         public ErroredModContainer() {
             super();
         }

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingContext.java

@@ -1,54 +1,56 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
+import com.mojang.logging.LogUtils;
 import net.minecraftforge.fml.config.IConfigSpec;
 import net.minecraftforge.fml.config.ModConfig;
-
+import org.slf4j.Logger;
+import java.util.function.BiPredicate;
 import java.util.function.Supplier;
 
-public class ModLoadingContext
-{
+public class ModLoadingContext {
+    private static final Logger LOGGER = LogUtils.getLogger();
     private static final ThreadLocal<ModLoadingContext> context = ThreadLocal.withInitial(ModLoadingContext::new);
+    private ModContainer activeContainer;
     private Object languageExtension;
-    private ModLoadingStage stage;
 
+    /**
+     * @deprecated Use the context provided by your language loader in your mod's constructor. Example for Java mods: {@snippet :
+     * @Mod("examplemod")
+     * public final class ExampleMod {
+     *      public ExampleMod(FMLJavaModLoadingContext context) {
+     *           // Use context from the param instead of FMLJavaModLoadingContext.get() or ModLoadingContext.get()
+     *      }
+     * }}
+     */
+    @Deprecated(forRemoval = true, since="1.21.1")
     public static ModLoadingContext get() {
         return context.get();
     }
 
-    private ModContainer activeContainer;
-
-    public void setActiveContainer(final ModContainer container) {
+    void setActiveContainer(final ModContainer container) {
         this.activeContainer = container;
         this.languageExtension = container == null ? null : container.contextExtension.get();
     }
 
-    public ModContainer getActiveContainer() {
-        return activeContainer == null ? ModList.get().getModContainerById("minecraft").orElseThrow(()->new RuntimeException("Where is minecraft???!")) : activeContainer;
-    }
-
+    /**
+     * @deprecated Going to be moved to ForgeHooks for Internal use.
+     */
+    @Deprecated(forRemoval = true, since="1.21.1")
     public String getActiveNamespace() {
         return activeContainer == null ? "minecraft" : activeContainer.getNamespace();
     }
 
+    public ModContainer getContainer() {
+        return activeContainer == null
+                ? ModList.getModContainerById("minecraft").orElseThrow(()->new RuntimeException("Where is minecraft???!"))
+                : activeContainer;
+    }
+
     /**
      * Register an {@link IExtensionPoint} with the mod container.
      * @param point The extension point to register
@@ -56,17 +58,66 @@ public class ModLoadingContext
      * @param <T> The type signature of the extension operator
      */
     public <T extends Record & IExtensionPoint<T>> void registerExtensionPoint(Class<? extends IExtensionPoint<T>> point, Supplier<T> extension) {
-        getActiveContainer().registerExtensionPoint(point, extension);
+        getContainer().registerExtensionPoint(point, extension);
+    }
+
+    /**
+     * Register a {@link IExtensionPoint.DisplayTest} with the mod container.
+     * <p>A shorthand for registering a DisplayTest with {@link #registerExtensionPoint(Class, Supplier)}.</p>
+     * @param displayTest The {@link IExtensionPoint.DisplayTest} to register
+     */
+    public void registerDisplayTest(IExtensionPoint.DisplayTest displayTest) {
+        getContainer().registerDisplayTest(() -> displayTest);
+    }
+
+    /**
+     * Register a {@link IExtensionPoint.DisplayTest} with the mod container.
+     * <p>A shorthand for registering a DisplayTest supplier with {@link #registerExtensionPoint(Class, Supplier)}.</p>
+     * @param displayTest The {@link Supplier<IExtensionPoint.DisplayTest>} to register
+     */
+    public void registerDisplayTest(Supplier<IExtensionPoint.DisplayTest> displayTest) {
+        getContainer().registerDisplayTest(displayTest);
+    }
+
+    /**
+     * Register a {@link IExtensionPoint.DisplayTest} with the mod container.
+     * <p>A shorthand for registering a DisplayTest with {@link #registerExtensionPoint(Class, Supplier)} that also
+     * creates the DisplayTest instance for you using the provided parameters.</p>
+     * @see IExtensionPoint.DisplayTest#DisplayTest(String, BiPredicate)
+     */
+    public void registerDisplayTest(String version, BiPredicate<String, Boolean> remoteVersionTest) {
+        getContainer().registerDisplayTest(new IExtensionPoint.DisplayTest(version, remoteVersionTest));
+    }
+
+    /**
+     * Register a {@link IExtensionPoint.DisplayTest} with the mod container.
+     * <p>A shorthand for registering a DisplayTest with {@link #registerExtensionPoint(Class, Supplier)} that also
+     * creates the DisplayTest instance for you using the provided parameters.</p>
+     * @see IExtensionPoint.DisplayTest#DisplayTest(Supplier, BiPredicate)
+     */
+    public void registerDisplayTest(Supplier<String> suppliedVersion, BiPredicate<String, Boolean> remoteVersionTest) {
+        getContainer().registerDisplayTest(new IExtensionPoint.DisplayTest(suppliedVersion, remoteVersionTest));
     }
 
     public void registerConfig(ModConfig.Type type, IConfigSpec<?> spec) {
-        getActiveContainer().addConfig(new ModConfig(type, spec, getActiveContainer()));
+        if (spec.isEmpty()) {
+            // This handles the case where a mod tries to register a config, without any options configured inside it.
+            LOGGER.debug("Attempted to register an empty config for type {} on mod {}", type, getContainer().getModId());
+            return;
+        }
+
+        getContainer().addConfig(new ModConfig(type, spec, getContainer()));
     }
 
     public void registerConfig(ModConfig.Type type, IConfigSpec<?> spec, String fileName) {
-        getActiveContainer().addConfig(new ModConfig(type, spec, getActiveContainer(), fileName));
-    }
+        if (spec.isEmpty()) {
+            // This handles the case where a mod tries to register a config, without any options configured inside it.
+            LOGGER.debug("Attempted to register an empty config for type {} on mod {} using file name {}", type, getContainer().getModId(), fileName);
+            return;
+        }
 
+        getContainer().addConfig(new ModConfig(type, spec, getContainer(), fileName));
+    }
 
     @SuppressWarnings("unchecked")
     public <T> T extension() {

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingException.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingPhase.java

@@ -1,9 +1,38 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
+/**
+ * Phases of mod loading, for grouping mod loading states.
+ */
 public enum ModLoadingPhase {
+    /**
+     * Special phase for exceptional situations and error handling, where mod loading cannot continue normally.
+     *
+     * <p>There is conventionally only one state with this phase.</p>
+     */
     ERROR, // Special state for error handling
+    /**
+     * Phase for discovering and gathering mods for loading.
+     */
     GATHER,
+    /**
+     * Phase for the loading of mods found from mod discovery.
+     *
+     * @see #GATHER
+     */
     LOAD,
+    /**
+     * Phase after mod loading has completed, for post-loading tasks.
+     *
+     * @see #LOAD
+     */
     COMPLETE,
-    DONE;
+    /**
+     * Marker phase for the last state in the full mod loading process.
+     */
+    DONE
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingStage.java

@@ -1,34 +1,57 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
+/**
+ * Mod loading stage of mod containers during the mod loading process. These will have a corresponding {@link ModLoadingState}
+ * in the basic mod loading process provided by FML.
+ *
+ * <p>Each mod loading stage has a global {@link DeferredWorkQueue}, which is populated during the execution of the state
+ * associated with this stage and emptied at the end of the state's execution.</p>
+ */
 public enum ModLoadingStage
 {
+    /**
+     * Special stage for exceptional situations and error handling.
+     */
     ERROR,
+    /**
+     * Validation of the mod list.
+     * TODO: figure out where this is used and why this exists instead of CONSTRUCT being the first normal stage
+     */
     VALIDATE,
+    /**
+     * Default stage of mod containers after construction.
+     */
     CONSTRUCT,
+    /**
+     * Common (non-side-specific) setup and initialization.
+     */
     COMMON_SETUP,
+    /**
+     * Side-specific setup and initialization.
+     *
+     * @see net.minecraftforge.api.distmarker.Dist
+     */
     SIDED_SETUP,
+    /**
+     * Stage for enqueuing {@link net.minecraftforge.fml.InterModComms} messages for later processing.
+     */
     ENQUEUE_IMC,
+    /**
+     * Stage for processing received messages though {@link net.minecraftforge.fml.InterModComms}.
+     */
     PROCESS_IMC,
+    /**
+     * Marks the completion of mod loading for this container.
+     */
     COMPLETE,
+    /**
+     * Marks the completion of the full mod loading process.
+     */
     DONE;
 
     private final DeferredWorkQueue deferredWorkQueue;
@@ -37,14 +60,27 @@ public enum ModLoadingStage
         deferredWorkQueue = new DeferredWorkQueue(this);
     }
 
+    /**
+     * {@return the next stage after this stage, or {@link #ERROR} if the exception is not {@code null}}
+     *
+     * @param exception the exception that occurred during this stage, may be {@code null}
+     */
     ModLoadingStage nextState(Throwable exception) {
         return exception != null ? ERROR : values()[this.ordinal()+1];
     }
 
+    /**
+     * {@return this stage, or {@link #ERROR} if the exception is not {@code null}}
+     *
+     * @param exception the exception that occurred during this stage, may be {@code null}
+     */
     public ModLoadingStage currentState(Throwable exception) {
         return exception != null ? ERROR : this;
     }
 
+    /**
+     * {@return the deferred work queue for this stage}
+     */
     public DeferredWorkQueue getDeferredWorkQueue() {
         return deferredWorkQueue;
     }

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingState.java

@@ -1,33 +1,182 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
-import net.minecraftforge.eventbus.api.Event;
-import net.minecraftforge.fml.event.IModBusEvent;
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 
-import java.util.List;
-import java.util.Optional;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
-import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.function.IntSupplier;
+import java.util.function.Supplier;
 
-public record ModLoadingState(String name, String previous, Function<ModList, String> message, ModLoadingPhase phase, Optional<Consumer<ModList>> inlineRunnable, Optional<IModStateTransition> transition) implements IModLoadingState {
+/**
+ * Implementation of the {@link IModLoadingState} interface.
+ *
+ * @param name           the name of this state
+ * @param previous       the name of the state immediately previous to this state
+ * @param message        a function returning a human-friendly message for this state
+ * @param phase          the mod loading phase this state belongs to
+ * @param inlineRunnable an optional runnable, which runs before starting the transition from this state to the next
+ * @param transition     optional state transition information
+ */
+@NullMarked
+public record ModLoadingState(
+    String name,
+    String previous,
+    Supplier<String> message,
+    IntSupplier size,
+    ModLoadingPhase phase,
+    @Nullable Runnable inlineRunnable,
+    @Nullable IModStateTransition transition
+) implements IModLoadingState {
     @Override
-    public <T extends Event & IModBusEvent> Optional<CompletableFuture<List<Throwable>>> buildTransition(final Executor syncExecutor, final Executor parallelExecutor, Function<Executor, CompletableFuture<Void>> preSyncTask, Function<Executor, CompletableFuture<Void>> postSyncTask) {
-        return transition.map(t->t.build(syncExecutor, parallelExecutor, preSyncTask, postSyncTask));
+    public @Nullable CompletableFuture<Void> buildTransition(
+        final Executor syncExecutor,
+        final Executor parallelExecutor,
+        final ProgressMeter progressBar,
+        final Function<Executor, CompletableFuture<Void>> preSyncTask,
+        final Function<Executor, CompletableFuture<Void>> postSyncTask
+    ) {
+        if (transition == null) return null;
+        return transition.build(name, syncExecutor, parallelExecutor, progressBar, preSyncTask, postSyncTask);
     }
 
+    /**
+     * {@return an empty mod loading state} The mod loading state has a blank human-readable message, no inline runnable,
+     * and no state transition information.
+     *
+     * @param name     the name of the state
+     * @param previous the name of the immediately previous state to this state
+     * @param phase    the mod loading phase the state belongs to
+     *
+     * @deprecated Use the builder
+     */
+    @Deprecated(since = "1.21.3", forRemoval = true)
     public static ModLoadingState empty(final String name, final String previous, final ModLoadingPhase phase) {
-        return new ModLoadingState(name, previous, ml->"", phase, Optional.empty(), Optional.empty());
+        return new ModLoadingState(name, previous, () -> "", () -> 0, phase, null, null);
     }
 
-    public static ModLoadingState withTransition(final String name, final String previous, final ModLoadingPhase phase, IModStateTransition transition) {
-        return new ModLoadingState(name, previous, ml->"Processing transition "+name, phase, Optional.empty(), Optional.of(transition));
+    /**
+     * Returns a mod loading state with state transition information and a default human-friendly message of
+     * {@code Processing transition [name]}.
+     *
+     * @param name       the name of the state
+     * @param previous   the name of the immediately previous state to this state
+     * @param phase      the mod loading phase the state belongs to
+     * @param transition the state transition information
+     *
+     * @deprecated Use the builder
+     */
+    @Deprecated(since = "1.21.3", forRemoval = true)
+    public static ModLoadingState withTransition(final String name, final String previous, final ModLoadingPhase phase,
+                                                 final IModStateTransition transition) {
+        return of(name, phase).after(previous).withTransition(transition);
     }
 
-    public static ModLoadingState withTransition(final String name, final String previous, final Function<ModList, String> message, final ModLoadingPhase phase, IModStateTransition transition) {
-        return new ModLoadingState(name, previous, message, phase, Optional.empty(), Optional.of(transition));
+    /**
+     * Returns a mod loading state with state transition information and a custom human-friendly message function.
+     *
+     * @param name       the name of the state
+     * @param previous   the name of the immediately previous state to this state
+     * @param message    a function returning a human-friendly message for this state
+     * @param phase      the mod loading phase the state belongs to
+     * @param transition the state transition information
+     * @return a mod loading state with state transition information and a custom message
+     *
+     * @deprecated Use the builder
+     */
+    @Deprecated(since = "1.21.3", forRemoval = true)
+    public static ModLoadingState withTransition(final String name, final String previous,
+                                                 final Supplier<String> message, final ModLoadingPhase phase,
+                                                 final IModStateTransition transition) {
+        return of(name, phase).after(previous).message(message).withTransition(transition);
     }
-    public static ModLoadingState withInline(final String name, final String previous, final ModLoadingPhase phase, Consumer<ModList> inline) {
-        return new ModLoadingState(name, previous, ml->"Processing work "+name, phase, Optional.of(inline), Optional.empty());
+
+    /**
+     * Returns a mod loading state with an inline runnable and a default human-friendly message of {@code Processing
+     * work [name]}.
+     *
+     * @param name     the name of the state
+     * @param previous the name of the immediately previous state to this state
+     * @param phase    the mod loading phase the state belongs to
+     * @param inline   an optional runnable, which runs before starting the transition from this state to the next
+     * @return a mod loading state with an inline runnable and default message
+     *
+     * @deprecated Use the builder
+     */
+    @Deprecated(since = "1.21.3", forRemoval = true)
+    public static ModLoadingState withInline(final String name, final String previous, final ModLoadingPhase phase,
+                                             final Runnable inline) {
+        return of(name, phase).after(previous).withInline(inline);
     }
-}
+
+    public static Builder of(final String name, final ModLoadingPhase phase) {
+        return new Builder(name, phase);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        return o instanceof ModLoadingState that
+                && this.phase == that.phase
+                && this.name.equals(that.name)
+                && this.previous.equals(that.previous);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = phase.hashCode();
+        result = 31 * result + name.hashCode();
+        result = 31 * result + previous.hashCode();
+        return result;
+    }
+
+    public static final class Builder {
+        private final String name;
+        private final ModLoadingPhase phase;
+        private String after = "";
+        private @Nullable Supplier<String> message = null;
+        private @Nullable IntSupplier size = null;
+
+        private Builder(final String name, final ModLoadingPhase phase) {
+            this.name = name;
+            this.phase = phase;
+        }
+
+        public Builder after(final ModLoadingState value) { return after(value.name()); }
+        public Builder after(final String value) {
+            this.after = value;
+            return this;
+        }
+
+        public Builder message(final String value) { return message(() -> value); }
+        public Builder message(final Supplier<String> value) {
+            this.message = value;
+            return this;
+        }
+
+        public Builder size(final int value) { return size(() -> value); }
+        public Builder size(final IntSupplier value) {
+            this.size = value;
+            return this;
+        }
+
+        public ModLoadingState empty() {
+            return new ModLoadingState(name, after, message != null ? message : () -> "", size != null ? size : () -> 0, phase, null, null);
+        }
+
+        public ModLoadingState withTransition(final IModStateTransition transition) {
+            return new ModLoadingState(name, after, message != null ? message : () -> "Processing transition " + name, size != null ? size : ModList::size, phase, null, transition);
+        }
+
+        public ModLoadingState withInline(final Runnable inline) {
+            return new ModLoadingState(name, after, message != null ? message : () -> "Processing work " + name, size != null ? size : () -> 0, phase, inline, null);
+        }
+    }
+}

fmlcore/src/main/java/net/minecraftforge/fml/ModLoadingWarning.java

@@ -1,60 +1,31 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
-import com.google.common.collect.Streams;
 import net.minecraftforge.forgespi.language.IModInfo;
 
-import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Stream;
 
-public class ModLoadingWarning
-{
-    /**
-     * Mod Info for mod with warning
-     */
-    private final IModInfo modInfo;
-    /**
-     * The stage where this warning was encountered
-     */
-    private final ModLoadingStage warningStage;
-
-    /**
-     * I18N message to use for display
-     */
-    private final String i18nMessage;
-
-    /**
-     * Context for message display
-     */
-    private final List<Object> context;
-
+/**
+ * @param modInfo Mod info for mod with warning
+ * @param warningStage The stage where this warning was encountered
+ * @param i18nMessage I18N message to use for display
+ * @param context Context for message display
+ */
+public record ModLoadingWarning(IModInfo modInfo, ModLoadingStage warningStage, String i18nMessage, List<Object> context) {
     public ModLoadingWarning(final IModInfo modInfo, final ModLoadingStage warningStage, final String i18nMessage, Object... context) {
-        this.modInfo = modInfo;
-        this.warningStage = warningStage;
-        this.i18nMessage = i18nMessage;
-        this.context = Arrays.asList(context);
+        this(modInfo, warningStage, i18nMessage, List.of(context));
+    }
+
+    public ModLoadingWarning {
+        context = List.copyOf(context);
     }
 
     public String formatToString() {
-        return Bindings.getMessageParser().get().parseMessage(i18nMessage, Streams.concat(Stream.of(modInfo, warningStage), context.stream()).toArray());
+        return Bindings.getMessageParser().get().parseMessage(i18nMessage, Stream.concat(Stream.of(modInfo, warningStage), context.stream()).toArray());
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModStateManager.java

@@ -1,3 +1,8 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
 import com.google.common.graph.GraphBuilder;
@@ -10,20 +15,19 @@ import java.util.function.Function;
 import java.util.stream.Collectors;
 
 @SuppressWarnings("UnstableApiUsage")
-public class ModStateManager {
-    static ModStateManager INSTANCE;
-    private final EnumMap<ModLoadingPhase, List<IModLoadingState>> stateMap;
+public final class ModStateManager {
+    private ModStateManager() {}
+    private static final EnumMap<ModLoadingPhase, List<IModLoadingState>> stateMap;
 
-    public ModStateManager() {
-        INSTANCE = this;
+    static {
         final var sp = ServiceLoader.load(FMLLoader.getGameLayer(), IModStateProvider.class);
-        this.stateMap = ServiceLoaderUtils.streamWithErrorHandling(sp, sce->{})
+        stateMap = ServiceLoaderUtils.streamWithErrorHandling(sp, _ -> {})
                 .map(IModStateProvider::getAllStates)
-                .<IModLoadingState>mapMulti(Iterable::forEach)
-                .collect(Collectors.groupingBy(IModLoadingState::phase, ()->new EnumMap<>(ModLoadingPhase.class), Collectors.toUnmodifiableList()));
+                .flatMap(List::stream)
+                .collect(Collectors.groupingBy(IModLoadingState::phase, () -> new EnumMap<>(ModLoadingPhase.class), Collectors.toUnmodifiableList()));
     }
 
-    public List<IModLoadingState> getStates(final ModLoadingPhase phase) {
+    public static List<IModLoadingState> getStates(final ModLoadingPhase phase) {
         var nodes = stateMap.get(phase);
         var lookup = nodes.stream().collect(Collectors.toMap(IModLoadingState::name, Function.identity()));
 
@@ -31,7 +35,20 @@ public class ModStateManager {
         var dummy = ModLoadingState.empty("", "", phase);
         nodes.forEach(graph::addNode);
         graph.addNode(dummy);
-        nodes.forEach(n->graph.putEdge(lookup.getOrDefault(n.previous(), dummy), n));
+        for (IModLoadingState node : nodes) {
+            graph.putEdge(lookup.getOrDefault(node.previous(), dummy), node);
+        }
         return TopologicalSort.topologicalSort(graph, Comparator.comparingInt(nodes::indexOf)).stream().filter(st->st!=dummy).toList();
     }
+
+    public static IModLoadingState findState(final String stateName) {
+        var result = stateMap.values()
+                .stream()
+                .flatMap(List::stream)
+                .filter(mls -> mls.name().equals(stateName))
+                .findFirst()
+                .orElse(null);
+        if (result != null) return result;
+        else throw new IllegalArgumentException("Unknown IModLoadingState: " + stateName);
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/ModStateTransitionHelper.java

@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.fml;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.Executor;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import org.jetbrains.annotations.ApiStatus;
+
+import net.minecraftforge.fml.IModStateTransition.EventGenerator;
+import net.minecraftforge.fml.event.IModBusEvent;
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+
+@ApiStatus.Internal
+final class ModStateTransitionHelper {
+    static final IModStateTransition NOOP = new NoopTransition();
+    record NoopTransition() implements IModStateTransition {
+        @Override
+        public ThreadSelector threadSelector() {
+            return ThreadSelector.SYNC;
+        }
+
+        @Override
+        public BiFunction<Executor, CompletableFuture<Void>, CompletableFuture<Void>> finalActivityGenerator() {
+            return (e, t) -> t.thenApplyAsync(Function.identity(), e);
+        }
+    }
+
+    static <V> CompletionStage<Void> completableFutureFromExceptionList(List<FutureResult<V>> t) {
+        if (t.stream().noneMatch(e -> e.exception() != null)) {
+            return CompletableFuture.completedFuture(null);
+        } else {
+            final var throwables = t.stream().map(FutureResult::exception).filter(Objects::nonNull).toList();
+            CompletableFuture<Void> cf = new CompletableFuture<>();
+            final RuntimeException accumulator = new RuntimeException();
+            cf.completeExceptionally(accumulator);
+            for (Throwable exception : throwables) {
+                if (exception instanceof CompletionException) {
+                    exception = exception.getCause();
+                }
+                if (exception.getSuppressed().length != 0) {
+                    for (Throwable throwable : exception.getSuppressed()) {
+                        accumulator.addSuppressed(throwable);
+                    }
+                } else {
+                    accumulator.addSuppressed(exception);
+                }
+            }
+            return cf;
+        }
+    }
+
+    /// Same as [#completableFutureFromExceptionList(List)] but specialised for a single future
+    static <V> CompletionStage<Void> completableFutureFromException(FutureResult<V> t) {
+        if (t.exception() == null) {
+            return CompletableFuture.completedFuture(null);
+        } else {
+            var exception = t.exception();
+            CompletableFuture<Void> cf = new CompletableFuture<>();
+            RuntimeException accumulator = new RuntimeException();
+            cf.completeExceptionally(accumulator);
+            if (exception instanceof CompletionException) {
+                exception = exception.getCause();
+            }
+            if (exception.getSuppressed().length != 0) {
+                for (Throwable throwable : exception.getSuppressed()) {
+                    accumulator.addSuppressed(throwable);
+                }
+            } else {
+                accumulator.addSuppressed(exception);
+            }
+            return cf;
+        }
+    }
+
+    record FutureResult<V>(V value, Throwable exception) {}
+
+    static <V> CompletableFuture<List<FutureResult<V>>> gather(Collection<? extends CompletableFuture<? extends V>> futures) {
+        var list = new ArrayList<FutureResult<V>>(futures.size());
+        var results = new CompletableFuture[futures.size()];
+
+        for (var future : futures) {
+            int i = list.size();
+            list.add(null);
+            @SuppressWarnings("unchecked") // Bypass a weird javac error with generic by forcing it to be the exact type we want.
+            var raw = ((CompletableFuture<V>)future);
+            results[i] = raw.whenComplete((result, exception) -> list.set(i, new FutureResult<>(result, exception)));
+        }
+
+        return CompletableFuture.allOf(results).handle((r, th)->null).thenApply(res -> list);
+    }
+
+    private static <T extends IModBusEvent> CompletableFuture<Void> addCompletableFutureTaskForModDispatch(
+        final Executor executor,
+        final ProgressMeter progressBar,
+        final EventGenerator<T> eventGenerator,
+        final BiFunction<ModLoadingStage, Throwable, ModLoadingStage> nextState
+     ) {
+        var modFutures = new LinkedHashMap<String, CompletableFuture<Void>>();
+        for (var mod : ModList.getLoadedMods()) {
+
+            CompletableFuture<Void> parent = null;
+            if (mod.dependencies.isEmpty()) {
+                parent = CompletableFuture.allOf();
+            } else {
+                var deps = new CompletableFuture[mod.dependencies.size()];
+                int idx = 0;
+                for (var depContainer : mod.dependencies) {
+                    var future = modFutures.get(depContainer.getModId());
+                    if (future == null)
+                        throw new IllegalStateException("Could not find dependency future " + depContainer.getModId() + " for " + mod.getModId());
+                    deps[idx++] = future;
+                }
+                parent = CompletableFuture.allOf(deps);
+            }
+
+            @SuppressWarnings("removal")
+            var dispatch = parent
+                .thenRunAsync(() -> {
+                    ModLoadingContext.get().setActiveContainer(mod);
+                    var handler = mod.activityMap.get(mod.modLoadingStage);
+                    if (handler != null)
+                        handler.run();
+                    mod.acceptEvent(eventGenerator.apply(mod));
+                }, executor)
+                .whenComplete((mc, exception) -> {
+                    mod.modLoadingStage = nextState.apply(mod.modLoadingStage, exception);
+                    progressBar.increment();
+                    ModLoadingContext.get().setActiveContainer(null);
+                });
+
+            modFutures.put(mod.getModId(), dispatch);
+        }
+
+        return gather(modFutures.values()).thenComposeAsync(ModStateTransitionHelper::completableFutureFromExceptionList, executor);
+    }
+
+    static <T extends IModBusEvent> CompletableFuture<Void> build(
+        final IModStateTransition transition,
+        final String name,
+        final Executor syncExecutor,
+        final Executor parallelExecutor,
+        final ProgressMeter progressBar,
+        final Function<Executor, CompletableFuture<Void>> preSyncTask,
+        final Function<Executor, CompletableFuture<Void>> postSyncTask
+    ) {
+        CompletableFuture<Void> future;
+        final var executor = transition.threadSelector().apply(syncExecutor, parallelExecutor);
+
+        final CompletableFuture<Void> preSyncTaskCF = preSyncTask.apply(syncExecutor);
+        CompletableFuture<Void> postEventDispatchCF = preSyncTaskCF
+            .thenRunAsync(() -> progressBar.label(progressBar.name() + ": dispatching " + name), parallelExecutor);
+
+        var eventGenerator = transition.eventFunction();
+        if (eventGenerator != null) {
+            BiFunction<ModLoadingStage, Throwable, ModLoadingStage> state = transition.nextModLoadingStage();
+            future = addCompletableFutureTaskForModDispatch(executor, progressBar, eventGenerator, state);
+
+            final CompletableFuture<Void> eventDispatchCF = future.handle(FutureResult::new)
+                    .thenCompose(ModStateTransitionHelper::completableFutureFromException);
+            postEventDispatchCF = postEventDispatchCF.thenComposeAsync(_ -> eventDispatchCF, parallelExecutor);
+        }
+
+        postEventDispatchCF = postEventDispatchCF.thenRun(() -> postSyncTask.apply(syncExecutor));
+
+        return transition.finalActivityGenerator().apply(syncExecutor, postEventDispatchCF);
+    }
+}

fmlcore/src/main/java/net/minecraftforge/fml/ModWorkManager.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
@@ -28,29 +14,20 @@ import java.util.concurrent.locks.LockSupport;
 
 import static net.minecraftforge.fml.Logging.LOADING;
 
-public class ModWorkManager {
+public final class ModWorkManager {
     private static final Logger LOGGER = LogManager.getLogger();
     private static final long PARK_TIME = TimeUnit.MILLISECONDS.toNanos(1);
-    public interface DrivenExecutor extends Executor {
-        boolean selfDriven();
-        boolean driveOne();
 
-        default void drive(Runnable ticker) {
-            if (!selfDriven()) {
-                while (driveOne()) {
-                    ticker.run();
-                }
-            } else {
-                // park for a bit so other threads can schedule
-                LockSupport.parkNanos(PARK_TIME);
-            }
-        }
+    public sealed interface DrivenExecutor extends Executor {
+        void drive(Runnable ticker);
     }
-    private static class SyncExecutor implements DrivenExecutor {
-        private ConcurrentLinkedDeque<Runnable> tasks = new ConcurrentLinkedDeque<>();
 
-        @Override
-        public boolean driveOne() {
+    private record SyncExecutor(ConcurrentLinkedDeque<Runnable> tasks) implements DrivenExecutor {
+        public SyncExecutor() {
+            this(new ConcurrentLinkedDeque<>());
+        }
+
+        private boolean driveOne() {
             final Runnable task = tasks.pollFirst();
             if (task != null) {
                 task.run();
@@ -58,45 +35,36 @@ public class ModWorkManager {
             return task != null;
         }
 
-        @Override
-        public boolean selfDriven() {
-            return false;
-        }
-
         @Override
         public void execute(final Runnable command) {
             tasks.addLast(command);
         }
+
+        @Override
+        public void drive(Runnable ticker) {
+            ticker.run();
+            while (true) {
+                if (!driveOne()) break;
+            }
+        }
     }
 
-    private static class WrappingExecutor implements DrivenExecutor {
-        private final Executor wrapped;
-
-        public WrappingExecutor(final Executor executor) {
-            this.wrapped = executor;
-        }
-
-        @Override
-        public boolean selfDriven() {
-            return true;
-        }
-
-        @Override
-        public boolean driveOne() {
-            return false;
-        }
-
+    private record WrappingExecutor(Executor wrapped) implements DrivenExecutor {
         @Override
         public void execute(final Runnable command) {
             wrapped.execute(command);
         }
+
+        @Override
+        public void drive(Runnable ticker) {
+            // Park for a bit so other threads can schedule
+            LockSupport.parkNanos(PARK_TIME);
+        }
     }
 
-    private static SyncExecutor syncExecutor;
+    private static final SyncExecutor syncExecutor = new SyncExecutor();
 
     public static DrivenExecutor syncExecutor() {
-        if (syncExecutor == null)
-            syncExecutor = new SyncExecutor();
         return syncExecutor;
     }
 
@@ -104,14 +72,8 @@ public class ModWorkManager {
         return new WrappingExecutor(executor);
     }
 
-    private static ForkJoinPool parallelThreadPool;
     public static Executor parallelExecutor() {
-        if (parallelThreadPool == null) {
-            final int loadingThreadCount = FMLConfig.loadingThreadCount();
-            LOGGER.debug(LOADING, "Using {} threads for parallel mod-loading", loadingThreadCount);
-            parallelThreadPool = new ForkJoinPool(loadingThreadCount, ModWorkManager::newForkJoinWorkerThread, null, false);
-        }
-        return parallelThreadPool;
+        return LazyInit.PARALLEL_EXECUTOR;
     }
 
     private static ForkJoinWorkerThread newForkJoinWorkerThread(ForkJoinPool pool) {
@@ -122,4 +84,14 @@ public class ModWorkManager {
         return thread;
     }
 
+    private static final class LazyInit {
+        private LazyInit() {}
+        private static final ForkJoinPool PARALLEL_EXECUTOR;
+
+        static {
+            final int loadingThreadCount = FMLConfig.getIntConfigValue(FMLConfig.ConfigValue.MAX_THREADS);
+            LOGGER.debug(LOADING, "Using {} threads for parallel mod-loading", loadingThreadCount);
+            PARALLEL_EXECUTOR = new ForkJoinPool(loadingThreadCount, ModWorkManager::newForkJoinWorkerThread, null, false);
+        }
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/OptionalMod.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
@@ -37,7 +23,7 @@ public final class OptionalMod<T>
         return new OptionalMod<>(modId);
     }
 
-    private static OptionalMod<?> EMPTY = new OptionalMod<>(true);
+    private static final OptionalMod<?> EMPTY = new OptionalMod<>(true);
     private static <T> OptionalMod<T> empty() {
         @SuppressWarnings("unchecked")
         OptionalMod<T> t = (OptionalMod<T>) EMPTY;
@@ -57,7 +43,7 @@ public final class OptionalMod<T>
     private T getValue()
     {
         if (!searched) {
-            this.value = ModList.get().<T>getModObjectById(this.modId).orElse(null);
+            this.value = ModList.<T>getModObjectById(this.modId).orElse(null);
             searched = true;
         }
         return this.value;
@@ -227,8 +213,8 @@ public final class OptionalMod<T>
     public boolean equals(Object obj)
     {
         if (this == obj) return true;
-        if (obj instanceof OptionalMod) {
-            return Objects.equals(((OptionalMod)obj).modId, modId);
+        if (obj instanceof OptionalMod<?> optionalMod) {
+            return Objects.equals(optionalMod.modId, modId);
         }
         return false;
     }

fmlcore/src/main/java/net/minecraftforge/fml/StartupMessageManager.java

@@ -1,37 +1,34 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
+import net.minecraftforge.fml.loading.progress.ProgressMeter;
+import net.minecraftforge.fml.loading.progress.StartupNotificationManager;
+
 import java.util.Optional;
 import java.util.function.Consumer;
 
 public class StartupMessageManager {
     public static void addModMessage(final String message) {
-        net.minecraftforge.fml.loading.progress.StartupMessageManager.addModMessage(message);
+        StartupNotificationManager.addModMessage(message);
     }
 
     public static Optional<Consumer<String>> modLoaderConsumer() {
-        return net.minecraftforge.fml.loading.progress.StartupMessageManager.modLoaderConsumer();
+        return StartupNotificationManager.modLoaderConsumer();
     }
 
     public static Optional<Consumer<String>> mcLoaderConsumer() {
-        return net.minecraftforge.fml.loading.progress.StartupMessageManager.mcLoaderConsumer();
+        return StartupNotificationManager.mcLoaderConsumer();
+    }
+
+    public static ProgressMeter addProgressBar(final String barName, final int count) {
+        return StartupNotificationManager.addProgressBar(barName, count);
+    }
+
+    public static ProgressMeter prependProgressBar(final String barName, final int count) {
+        return StartupNotificationManager.prependProgressBar(barName, count);
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/ThreadSelector.java

@@ -1,3 +1,8 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml;
 
 import java.util.concurrent.Executor;

fmlcore/src/main/java/net/minecraftforge/fml/VersionChecker.java

@@ -1,27 +1,12 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml;
 
 import com.google.gson.Gson;
 import net.minecraftforge.fml.loading.FMLConfig;
-import net.minecraftforge.fml.loading.FMLLoader;
 import net.minecraftforge.forgespi.language.IModInfo;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -49,81 +34,72 @@ import java.util.zip.GZIPInputStream;
 
 import static net.minecraftforge.fml.VersionChecker.Status.*;
 
-public class VersionChecker
-{
+public class VersionChecker {
     private static final Logger LOGGER = LogManager.getLogger();
     private static final int MAX_HTTP_REDIRECTS = Integer.getInteger("http.maxRedirects", 20);
     private static final int HTTP_TIMEOUT_SECS = Integer.getInteger("http.timeoutSecs", 15);
 
-    public enum Status
-    {
+    public enum Status {
         PENDING(),
         FAILED(),
         UP_TO_DATE(),
-        OUTDATED(3, true),
+        OUTDATED(3, true, true),
         AHEAD(),
         BETA(),
-        BETA_OUTDATED(6, true);
+        BETA_OUTDATED(6, true, true);
 
-        final int sheetOffset;
-        final boolean draw, animated;
+        private final int sheetOffset;
+        private final boolean draw, animated;
 
-        Status()
-        {
+        Status() {
             this(0, false, false);
         }
 
-        Status(int sheetOffset)
-        {
-            this(sheetOffset, true, false);
-        }
-
-        Status(int sheetOffset, boolean animated)
-        {
-            this(sheetOffset, true, animated);
-        }
-
-        Status(int sheetOffset, boolean draw, boolean animated)
-        {
+        Status(int sheetOffset, boolean draw, boolean animated) {
             this.sheetOffset = sheetOffset;
             this.draw = draw;
             this.animated = animated;
         }
 
-        public int getSheetOffset()
-        {
+        public int getSheetOffset() {
             return sheetOffset;
         }
 
-        public boolean shouldDraw()
-        {
+        public boolean shouldDraw() {
             return draw;
         }
 
-        public boolean isAnimated()
-        {
+        public boolean isAnimated() {
             return animated;
         }
 
+        public boolean isOutdated() {
+            return this == OUTDATED || this == BETA_OUTDATED;
+        }
     }
 
     public record CheckResult(VersionChecker.Status status, ComparableVersion target, Map<ComparableVersion, String> changes, String url) {}
 
-    public static void startVersionCheck()
-    {
-        new Thread("Forge Version Check")
-        {
+    public static void startVersionCheck() {
+        new Thread("Forge Version Check") {
             private HttpClient client;
+            private String mcVersion;
+            private String agent;
 
             @Override
-            public void run()
-            {
-                if (!FMLConfig.runVersionCheck())
-                {
+            public void run() {
+                if (!FMLConfig.getBoolConfigValue(FMLConfig.ConfigValue.VERSION_CHECK)) {
                     LOGGER.info("Global Forge version check system disabled, no further processing.");
                     return;
                 }
 
+                var mc = ModList.getModContainerById("minecraft");
+                var forge = ModList.getModContainerById("forge");
+                this.mcVersion = mc.get().getModInfo().getVersion().toString();
+
+                this.agent = "Java-http-client/" + System.getProperty("java.version")
+                    + " MinecraftForge/" + mcVersion + '-' + forge.get().getModInfo().getVersion();
+
                 client = HttpClient.newBuilder().connectTimeout(Duration.ofSeconds(HTTP_TIMEOUT_SECS)).build();
                 gatherMods().forEach(this::process);
             }
@@ -131,22 +107,23 @@ public class VersionChecker
             /**
              * Returns the response body as a String for the given URL while following redirects
              */
-            private String openUrlString(URL url) throws IOException, URISyntaxException, InterruptedException {
+            private String openUrlString(URL url, IModInfo mod) throws IOException, URISyntaxException, InterruptedException {
                 URL currentUrl = url;
-                for (int redirects = 0; redirects < MAX_HTTP_REDIRECTS; redirects++)
-                {
+                var userAgent = this.agent + ' ' + mod.getModId() + '/' + mod.getVersion();
+
+                for (int redirects = 0; redirects < MAX_HTTP_REDIRECTS; redirects++) {
                     var request = HttpRequest.newBuilder()
                             .uri(currentUrl.toURI())
                             .timeout(Duration.ofSeconds(HTTP_TIMEOUT_SECS))
                             .setHeader("Accept-Encoding", "gzip")
+                            .setHeader("User-Agent", userAgent)
                             .GET()
                             .build();
 
                     final HttpResponse<InputStream> response = client.send(request, HttpResponse.BodyHandlers.ofInputStream());
 
                     int responseCode = response.statusCode();
-                    if (responseCode >= 300 && responseCode <= 399)
-                    {
+                    if (responseCode >= 300 && responseCode <= 399) {
                         String newLocation = response.headers().firstValue("Location")
                                 .orElseThrow(() -> new IOException("Got a 3xx response code but Location header was null while trying to fetch " + url));
                         currentUrl = new URL(currentUrl, newLocation);
@@ -156,82 +133,64 @@ public class VersionChecker
                     final boolean isGzipEncoded = response.headers().firstValue("Content-Encoding").orElse("").equals("gzip");
 
                     final String bodyStr;
-                    try (InputStream inStream = isGzipEncoded ? new GZIPInputStream(response.body()) : response.body())
-                    {
-                        try (var bufferedReader = new BufferedReader(new InputStreamReader(inStream)))
-                        {
-                            bodyStr = bufferedReader.lines().collect(Collectors.joining("\n"));
-                        }
+                    try (var inStream = isGzipEncoded ? new GZIPInputStream(response.body()) : response.body();
+                         var bufferedReader = new BufferedReader(new InputStreamReader(inStream))
+                    ) {
+                        bodyStr = bufferedReader.lines().collect(Collectors.joining("\n"));
                     }
                     return bodyStr;
                 }
                 throw new IOException("Too many redirects while trying to fetch " + url);
             }
 
-            private void process(IModInfo mod)
-            {
+            private void process(IModInfo mod) {
                 Status status = PENDING;
                 ComparableVersion target = null;
                 Map<ComparableVersion, String> changes = null;
                 String display_url = null;
-                try
-                {
+                try {
                     if (mod.getUpdateURL().isEmpty()) return;
                     URL url = mod.getUpdateURL().get();
                     LOGGER.info("[{}] Starting version check at {}", mod.getModId(), url.toString());
 
-                    String data = openUrlString(url);
+                    String data = openUrlString(url, mod);
 
                     LOGGER.debug("[{}] Received version check data:\n{}", mod.getModId(), data);
 
-
                     @SuppressWarnings("unchecked")
                     Map<String, Object> json = new Gson().fromJson(data, Map.class);
                     @SuppressWarnings("unchecked")
                     Map<String, String> promos = (Map<String, String>)json.get("promos");
                     display_url = (String)json.get("homepage");
 
-                    var mcVersion = FMLLoader.versionInfo().mcVersion();
                     String rec = promos.get(mcVersion + "-recommended");
                     String lat = promos.get(mcVersion + "-latest");
                     ComparableVersion current = new ComparableVersion(mod.getVersion().toString());
 
-                    if (rec != null)
-                    {
+                    if (rec != null) {
                         ComparableVersion recommended = new ComparableVersion(rec);
                         int diff = recommended.compareTo(current);
 
                         if (diff == 0)
                             status = UP_TO_DATE;
-                        else if (diff < 0)
-                        {
+                        else if (diff < 0) {
                             status = AHEAD;
-                            if (lat != null)
-                            {
+                            if (lat != null) {
                                 ComparableVersion latest = new ComparableVersion(lat);
-                                if (current.compareTo(latest) < 0)
-                                {
+                                if (current.compareTo(latest) < 0) {
                                     status = OUTDATED;
                                     target = latest;
                                 }
                             }
-                        }
-                        else
-                        {
+                        } else {
                             status = OUTDATED;
                             target = recommended;
                         }
-                    }
-                    else if (lat != null)
-                    {
+                    } else if (lat != null) {
                         ComparableVersion latest = new ComparableVersion(lat);
-                        if (current.compareTo(latest) < 0)
-                            status = BETA_OUTDATED;
-                        else
-                            status = BETA;
+                        status = current.compareTo(latest) < 0 ? BETA_OUTDATED : BETA;
                         target = latest;
-                    }
-                    else
+                    } else
                         status = BETA;
 
                     LOGGER.info("[{}] Found status: {} Current: {} Target: {}", mod.getModId(), status, current, target);
@@ -239,52 +198,42 @@ public class VersionChecker
                     changes = new LinkedHashMap<>();
                     @SuppressWarnings("unchecked")
                     Map<String, String> tmp = (Map<String, String>)json.get(mcVersion);
-                    if (tmp != null)
-                    {
+                    if (tmp != null) {
                         List<ComparableVersion> ordered = new ArrayList<>();
-                        for (String key : tmp.keySet())
-                        {
+                        for (String key : tmp.keySet()) {
                             ComparableVersion ver = new ComparableVersion(key);
                             if (ver.compareTo(current) > 0 && (target == null || ver.compareTo(target) < 1))
-                            {
                                 ordered.add(ver);
-                            }
                         }
                         Collections.sort(ordered);
 
-                        for (ComparableVersion ver : ordered)
-                        {
+                        for (ComparableVersion ver : ordered) {
                             changes.put(ver, tmp.get(ver.toString()));
                         }
                     }
-                }
-                catch (Exception e)
-                {
+                } catch (Exception e) {
                     LOGGER.warn("Failed to process update information", e);
                     status = FAILED;
                 }
-                results.put(mod, new CheckResult(status, target, changes, display_url));
+                RESULTS.put(mod, new CheckResult(status, target, changes, display_url));
             }
         }.start();
     }
 
     // Gather a list of mods that have opted in to this update system by providing a URL.
-    private static List<IModInfo> gatherMods()
-    {
+    private static List<IModInfo> gatherMods() {
         List<IModInfo> ret = new LinkedList<>();
-        for (IModInfo info : ModList.get().getMods()) {
+        for (IModInfo info : ModList.getMods()) {
             if (info.getUpdateURL().isPresent())
                 ret.add(info);
         }
         return ret;
     }
 
-    private static Map<IModInfo, CheckResult> results = new ConcurrentHashMap<>();
+    private static final Map<IModInfo, CheckResult> RESULTS = new ConcurrentHashMap<>();
     private static final CheckResult PENDING_CHECK = new CheckResult(PENDING, null, null, null);
 
-    public static CheckResult getResult(IModInfo mod)
-    {
-        return results.getOrDefault(mod, PENDING_CHECK);
+    public static CheckResult getResult(IModInfo mod) {
+        return RESULTS.getOrDefault(mod, PENDING_CHECK);
     }
-
 }

fmlcore/src/main/java/net/minecraftforge/fml/config/ConfigFileTypeHandler.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml.config;
@@ -24,11 +10,12 @@ import com.electronwill.nightconfig.core.file.CommentedFileConfig;
 import com.electronwill.nightconfig.core.file.FileWatcher;
 import com.electronwill.nightconfig.core.io.ParsingException;
 import com.electronwill.nightconfig.core.io.WritingMode;
+import com.mojang.logging.LogUtils;
 import net.minecraftforge.fml.loading.FMLConfig;
 import net.minecraftforge.fml.loading.FMLPaths;
 import org.apache.commons.io.FilenameUtils;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
 
 import java.io.IOException;
 import java.nio.file.Files;
@@ -38,9 +25,66 @@ import java.util.function.Function;
 import static net.minecraftforge.fml.config.ConfigTracker.CONFIG;
 
 public class ConfigFileTypeHandler {
-    private static final Logger LOGGER = LogManager.getLogger();
-    static ConfigFileTypeHandler TOML = new ConfigFileTypeHandler();
-    private static final Path defaultConfigPath = FMLPaths.GAMEDIR.get().resolve(FMLConfig.defaultConfigPath());
+    private static final Logger LOGGER = LogUtils.getLogger();
+    private static final Path defaultConfigPath = FMLPaths.GAMEDIR.get().resolve(FMLConfig.getConfigValue(FMLConfig.ConfigValue.DEFAULT_CONFIG_PATH));
+
+    private static final ConfigFileTypeHandler CLIENT = new ConfigFileTypeHandler(ModConfig.Type.CLIENT);
+    private static final ConfigFileTypeHandler COMMON = new ConfigFileTypeHandler(ModConfig.Type.COMMON);
+    private static final ConfigFileTypeHandler SERVER = new ConfigFileTypeHandler(ModConfig.Type.SERVER);
+
+    private final @Nullable ModConfig.Type type;
+    private @Nullable FileWatcher watcher;
+
+    // exists for bin compat
+    public ConfigFileTypeHandler() {
+        this(null);
+    }
+
+    private ConfigFileTypeHandler(@Nullable ModConfig.Type type) {
+        this.type = type;
+    }
+
+    /**
+     * Gets the handler for the given {@link ModConfig.Type}.
+     *
+     * @param type The type to get the handler for
+     * @return The handler
+     */
+    static ConfigFileTypeHandler get(ModConfig.Type type) {
+        return switch (type) {
+            case CLIENT -> CLIENT;
+            case COMMON -> COMMON;
+            case SERVER -> SERVER;
+        };
+    }
+
+    /**
+     * Gets the {@link FileWatcher} for this handler, creating it if it doesn't exist and/or has been stopped.
+     *
+     * @return The watcher
+     *
+     * @apiNote This is package-private so modders can't just call {@link FileWatcher#stop()} and fuck up everything.
+     */
+    FileWatcher getWatcher() {
+        if (this.watcher == null) {
+            LOGGER.debug(CONFIG, "Starting watcher for handler: {}", this);
+            this.watcher = new FileWatcher();
+        }
+
+        return this.watcher;
+    }
+
+    /**
+     * Stops the {@link FileWatcher} for this handler, and sets it to null afterward. Use this instead of
+     * {@link FileWatcher#stop()}.
+     */
+    void stopWatcher() {
+        if (this.watcher == null) return;
+
+        LOGGER.debug(CONFIG, "Stopping watcher for hander: {}", this);
+        this.watcher.stop();
+        this.watcher = null;
+    }
 
     public Function<ModConfig, CommentedFileConfig> reader(Path configBasePath) {
         return (c) -> {
@@ -51,7 +95,7 @@ public class ConfigFileTypeHandler {
                     onFileNotFound((newfile, configFormat)-> setupConfigFile(c, newfile, configFormat)).
                     writingMode(WritingMode.REPLACE).
                     build();
-            LOGGER.debug(CONFIG, "Built TOML config for {}", configPath.toString());
+            LOGGER.debug(CONFIG, "Built TOML config for {}", configPath);
             try
             {
                 configData.load();
@@ -60,13 +104,9 @@ public class ConfigFileTypeHandler {
             {
                 throw new ConfigLoadingException(c, ex);
             }
-            LOGGER.debug(CONFIG, "Loaded TOML config file {}", configPath.toString());
-            try {
-                FileWatcher.defaultInstance().addWatch(configPath, new ConfigWatcher(c, configData, Thread.currentThread().getContextClassLoader()));
-                LOGGER.debug(CONFIG, "Watching TOML config file {} for changes", configPath.toString());
-            } catch (IOException e) {
-                throw new RuntimeException("Couldn't watch config file", e);
-            }
+            LOGGER.debug(CONFIG, "Loaded TOML config file {}", configPath);
+            this.getWatcher().addWatch(configPath, new ConfigWatcher(c, configData, Thread.currentThread().getContextClassLoader()));
+            LOGGER.debug(CONFIG, "Watching TOML config file {} for changes", configPath);
             return configData;
         };
     }
@@ -74,13 +114,16 @@ public class ConfigFileTypeHandler {
     public void unload(Path configBasePath, ModConfig config) {
         Path configPath = configBasePath.resolve(config.getFileName());
         try {
-            FileWatcher.defaultInstance().removeWatch(configBasePath.resolve(config.getFileName()));
+            this.getWatcher().removeWatch(configPath);
         } catch (RuntimeException e) {
-            LOGGER.error("Failed to remove config {} from tracker!", configPath.toString(), e);
+            LOGGER.error("Failed to remove config {} from tracker!", configPath, e);
         }
     }
 
-    private boolean setupConfigFile(final ModConfig modConfig, final Path file, final ConfigFormat<?> conf) throws IOException {
+    private static boolean setupConfigFile(final ModConfig modConfig, final Path file, final ConfigFormat<?> conf) throws IOException {
+        if (!Files.isDirectory(file.getParent())) {
+            Files.createDirectories(file.getParent());
+        }
         Path p = defaultConfigPath.resolve(modConfig.getFileName());
         if (Files.exists(p)) {
             LOGGER.info(CONFIG, "Loading default config file from path {}", p);
@@ -124,17 +167,16 @@ public class ConfigFileTypeHandler {
         }
     }
 
-    private static class ConfigWatcher implements Runnable {
-        private final ModConfig modConfig;
-        private final CommentedFileConfig commentedFileConfig;
-        private final ClassLoader realClassLoader;
-
-        ConfigWatcher(final ModConfig modConfig, final CommentedFileConfig commentedFileConfig, final ClassLoader classLoader) {
-            this.modConfig = modConfig;
-            this.commentedFileConfig = commentedFileConfig;
-            this.realClassLoader = classLoader;
-        }
+    @Override
+    public String toString() {
+        return "ConfigFileTypeHandler[" + (type != null ? type : "UNKNOWN") + "]";
+    }
 
+    private record ConfigWatcher(
+            ModConfig modConfig,
+            CommentedFileConfig commentedFileConfig,
+            ClassLoader realClassLoader
+    ) implements Runnable {
         @Override
         public void run() {
             // Force the regular classloader onto the special thread

fmlcore/src/main/java/net/minecraftforge/fml/config/ConfigTracker.java

@@ -1,75 +1,77 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml.config;
 
 import com.electronwill.nightconfig.core.CommentedConfig;
 import com.electronwill.nightconfig.core.file.CommentedFileConfig;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.apache.logging.log4j.Marker;
-import org.apache.logging.log4j.MarkerManager;
+import com.mojang.logging.LogUtils;
+import net.minecraftforge.fml.loading.FMLEnvironment;
+import net.minecraftforge.fml.loading.FMLPaths;
+import org.slf4j.Logger;
+import org.slf4j.Marker;
+import org.slf4j.MarkerFactory;
 
 import java.nio.file.Path;
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 
-public class ConfigTracker {
-    private static final Logger LOGGER = LogManager.getLogger();
-    static final Marker CONFIG = MarkerManager.getMarker("CONFIG");
-    public static final ConfigTracker INSTANCE = new ConfigTracker();
-    private final ConcurrentHashMap<String, ModConfig> fileMap;
-    private final EnumMap<ModConfig.Type, Set<ModConfig>> configSets;
-    private final ConcurrentHashMap<String, Map<ModConfig.Type, ModConfig>> configsByMod;
+public final class ConfigTracker {
+    private ConfigTracker() {}
 
-    private ConfigTracker() {
-        this.fileMap = new ConcurrentHashMap<>();
-        this.configSets = new EnumMap<>(ModConfig.Type.class);
-        this.configsByMod = new ConcurrentHashMap<>();
-        this.configSets.put(ModConfig.Type.CLIENT, Collections.synchronizedSet(new LinkedHashSet<>()));
-        this.configSets.put(ModConfig.Type.COMMON, Collections.synchronizedSet(new LinkedHashSet<>()));
-//        this.configSets.put(ModConfig.Type.PLAYER, new ConcurrentSkipListSet<>());
-        this.configSets.put(ModConfig.Type.SERVER, Collections.synchronizedSet(new LinkedHashSet<>()));
-    }
+    private static final Logger LOGGER = LogUtils.getLogger();
+    static final Marker CONFIG = MarkerFactory.getMarker("CONFIG");
+    private static final ConcurrentHashMap<String, ModConfig> FILE_MAP = new ConcurrentHashMap<>();
+    private static final Map<ModConfig.Type, Set<ModConfig>> CONFIG_SETS = Map.of(
+            ModConfig.Type.CLIENT, Collections.synchronizedSet(new LinkedHashSet<>()),
+            ModConfig.Type.COMMON, Collections.synchronizedSet(new LinkedHashSet<>()),
+            ModConfig.Type.SERVER, Collections.synchronizedSet(new LinkedHashSet<>())
+    );
+    private static final ConcurrentHashMap<String, Map<ModConfig.Type, ModConfig>> CONFIGS_BY_MOD = new ConcurrentHashMap<>();
 
-    void trackConfig(final ModConfig config) {
-        if (this.fileMap.containsKey(config.getFileName())) {
-            LOGGER.error(CONFIG,"Detected config file conflict {} between {} and {}", config.getFileName(), this.fileMap.get(config.getFileName()).getModId(), config.getModId());
+    static void trackConfig(final ModConfig config) {
+        if (FILE_MAP.containsKey(config.getFileName())) {
+            LOGGER.error(CONFIG,"Detected config file conflict {} between {} and {}", config.getFileName(), FILE_MAP.get(config.getFileName()).getModId(), config.getModId());
             throw new RuntimeException("Config conflict detected!");
         }
-        this.fileMap.put(config.getFileName(), config);
-        this.configSets.get(config.getType()).add(config);
-        this.configsByMod.computeIfAbsent(config.getModId(), (k)->new EnumMap<>(ModConfig.Type.class)).put(config.getType(), config);
+        FILE_MAP.put(config.getFileName(), config);
+        CONFIG_SETS.get(config.getType()).add(config);
+        CONFIGS_BY_MOD.computeIfAbsent(config.getModId(), _ -> new EnumMap<>(ModConfig.Type.class)).put(config.getType(), config);
         LOGGER.debug(CONFIG, "Config file {} for {} tracking", config.getFileName(), config.getModId());
     }
 
-    public void loadConfigs(ModConfig.Type type, Path configBasePath) {
+    public static void loadConfigs(ModConfig.Type type, Path configBasePath) {
         LOGGER.debug(CONFIG, "Loading configs type {}", type);
-        this.configSets.get(type).forEach(config -> openConfig(config, configBasePath));
+        for (ModConfig config : CONFIG_SETS.get(type)) {
+            openConfig(config, configBasePath);
+        }
     }
 
-    public void unloadConfigs(ModConfig.Type type, Path configBasePath) {
+    // TODO: [FML] This is only called for the server (outside of forceUnload)
+    // rethink config implementation for eventual FML rewrite
+    public static void unloadConfigs(ModConfig.Type type, Path configBasePath) {
         LOGGER.debug(CONFIG, "Unloading configs type {}", type);
-        this.configSets.get(type).forEach(config -> closeConfig(config, configBasePath));
+        for (ModConfig config : CONFIG_SETS.get(type)) {
+            closeConfig(config, configBasePath);
+        }
+        ConfigFileTypeHandler.get(type).stopWatcher();
     }
 
-    private void openConfig(final ModConfig config, final Path configBasePath) {
+    // If there is a better way to do this, please tell me. Because this is FUCKED
+    public static void forceUnload() {
+        // This is how ModStateProvider handles loading configs. So we're doing the same but with unloadConfigs instead
+        if (FMLEnvironment.dist.isClient())
+            unloadConfigs(ModConfig.Type.CLIENT, FMLPaths.CONFIGDIR.get());
+
+        unloadConfigs(ModConfig.Type.COMMON, FMLPaths.CONFIGDIR.get());
+
+        // just in case server watcher is still alive somehow...
+        ConfigFileTypeHandler.get(ModConfig.Type.SERVER).stopWatcher();
+    }
+
+    private static void openConfig(final ModConfig config, final Path configBasePath) {
         LOGGER.trace(CONFIG, "Loading config file type {} at {} for {}", config.getType(), config.getFileName(), config.getModId());
         final CommentedFileConfig configData = config.getHandler().reader(configBasePath).apply(config);
         config.setConfigData(configData);
@@ -77,17 +79,21 @@ public class ConfigTracker {
         config.save();
     }
 
-    private void closeConfig(final ModConfig config, final Path configBasePath) {
+    private static void closeConfig(final ModConfig config, final Path configBasePath) {
         if (config.getConfigData() != null) {
             LOGGER.trace(CONFIG, "Closing config file type {} at {} for {}", config.getType(), config.getFileName(), config.getModId());
-            config.save();
+            // stop the filewatcher before we save the file and close it, so reload doesn't fire
             config.getHandler().unload(configBasePath, config);
+            var unloading = IConfigEvent.unloading(config);
+            if (unloading != null)
+                config.fireEvent(unloading);
+            config.save();
             config.setConfigData(null);
         }
     }
 
-    public void loadDefaultServerConfigs() {
-        configSets.get(ModConfig.Type.SERVER).forEach(modConfig -> {
+    public static void loadDefaultServerConfigs() {
+        CONFIG_SETS.get(ModConfig.Type.SERVER).forEach(modConfig -> {
             final CommentedConfig commentedConfig = CommentedConfig.inMemory();
             modConfig.getSpec().correct(commentedConfig);
             modConfig.setConfigData(commentedConfig);
@@ -95,16 +101,16 @@ public class ConfigTracker {
         });
     }
 
-    public String getConfigFileName(String modId, ModConfig.Type type) {
-        return Optional.ofNullable(configsByMod.getOrDefault(modId, Collections.emptyMap()).getOrDefault(type, null)).
+    public static String getConfigFileName(String modId, ModConfig.Type type) {
+        return Optional.ofNullable(CONFIGS_BY_MOD.getOrDefault(modId, Collections.emptyMap()).getOrDefault(type, null)).
                 map(ModConfig::getFullPath).map(Object::toString).orElse(null);
     }
 
-    public Map<ModConfig.Type, Set<ModConfig>> configSets() {
-        return configSets;
+    public static Map<ModConfig.Type, Set<ModConfig>> configSets() {
+        return CONFIG_SETS;
     }
 
-    public ConcurrentHashMap<String, ModConfig> fileMap() {
-        return fileMap;
+    public static ConcurrentHashMap<String, ModConfig> fileMap() {
+        return FILE_MAP;
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/config/IConfigEvent.java

@@ -1,12 +1,21 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml.config;
 
-import net.minecraftforge.eventbus.api.Event;
+import net.minecraftforge.eventbus.api.event.InheritableEvent;
 import net.minecraftforge.fml.Bindings;
 
 import java.util.function.Function;
 
+import org.jetbrains.annotations.Nullable;
+
 public interface IConfigEvent {
-    record ConfigConfig(Function<ModConfig, IConfigEvent> loading, Function<ModConfig, IConfigEvent> reloading) {}
+    // TODO: [FML] Get rid of this indirection somehow
+    record ConfigConfig(Function<ModConfig, IConfigEvent> loading, Function<ModConfig, IConfigEvent> reloading, @Nullable Function<ModConfig, IConfigEvent> unloading) {}
+
     ConfigConfig CONFIGCONFIG = Bindings.getConfigConfiguration().get();
 
     static IConfigEvent reloading(ModConfig modConfig) {
@@ -15,10 +24,13 @@ public interface IConfigEvent {
     static IConfigEvent loading(ModConfig modConfig) {
         return CONFIGCONFIG.loading().apply(modConfig);
     }
+    @Nullable static IConfigEvent unloading(ModConfig modConfig) {
+        return CONFIGCONFIG.unloading() == null ? null : CONFIGCONFIG.unloading().apply(modConfig);
+    }
     ModConfig getConfig();
 
     @SuppressWarnings("unchecked")
-    default <T extends Event & IConfigEvent> T self() {
+    default <T extends InheritableEvent & IConfigEvent> T self() {
         return (T) this;
     }
 }

fmlcore/src/main/java/net/minecraftforge/fml/config/IConfigSpec.java

@@ -1,3 +1,8 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
 package net.minecraftforge.fml.config;
 
 import com.electronwill.nightconfig.core.CommentedConfig;

fmlcore/src/main/java/net/minecraftforge/fml/config/ModConfig.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml.config;
@@ -27,6 +13,7 @@ import net.minecraftforge.fml.loading.StringUtils;
 
 import java.io.ByteArrayInputStream;
 import java.nio.file.Path;
+import java.util.Locale;
 import java.util.concurrent.Callable;
 
 public class ModConfig
@@ -37,15 +24,14 @@ public class ModConfig
     private final ModContainer container;
     private final ConfigFileTypeHandler configHandler;
     private CommentedConfig configData;
-    private Callable<Void> saveHandler;
 
     public ModConfig(final Type type, final IConfigSpec<?> spec, final ModContainer container, final String fileName) {
         this.type = type;
         this.spec = spec;
         this.fileName = fileName;
         this.container = container;
-        this.configHandler = ConfigFileTypeHandler.TOML;
-        ConfigTracker.INSTANCE.trackConfig(this);
+        this.configHandler = ConfigFileTypeHandler.get(type);
+        ConfigTracker.trackConfig(this);
     }
 
     public ModConfig(final Type type, final IConfigSpec<?> spec, final ModContainer activeContainer) {
@@ -54,8 +40,9 @@ public class ModConfig
 
     private static String defaultConfigName(Type type, String modId) {
         // config file name would be "forge-client.toml" and "forge-server.toml"
-        return String.format("%s-%s.toml", modId, type.extension());
+        return modId + '-' + type.extension() + ".toml";
     }
+
     public Type getType() {
         return type;
     }

fmlcore/src/main/java/net/minecraftforge/fml/event/IModBusEvent.java

@@ -1,26 +1,37 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml.event;
 
+import net.minecraftforge.eventbus.api.bus.BusGroup;
+import net.minecraftforge.eventbus.api.bus.EventBus;
+import net.minecraftforge.eventbus.api.event.InheritableEvent;
+import org.jspecify.annotations.NonNull;
+
 /**
- * Marker interface for events dispatched on the ModLifecycle event bus instead of the primary event bus
+ * Marker interface for mod lifecycle events dispatched on the
+ * {@linkplain net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext#getModBusGroup() mod BusGroup} instead
+ * of the {@linkplain BusGroup#DEFAULT default BusGroup}.
+ *
+ * @apiNote Each mod gets its own unique mod BusGroup instance, obtained from the mod loading context. Most events
+ *          should go on the default BusGroup.
  */
-public interface IModBusEvent {
+public interface IModBusEvent extends InheritableEvent {
+    /**
+     * @param modEventBusGroup Obtained from {@link net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext#getModBusGroup()} or your language provider's equivalent.
+     * @param eventClass The event type you want to get the associated bus for.
+     */
+    static <T extends IModBusEvent> @NonNull EventBus<@NonNull T> getBus(@NonNull BusGroup modEventBusGroup, @NonNull Class<T> eventClass) {
+        // Do not copy! Temporary solution until the FML rewrite is complete. May throw in future
+        // without prior notice.
+        //
+        // Mods creating their own events should directly assign the result of the create method to a
+        // static final field in their event class, without wrapping or calling multiple times.
+        //
+        // Mods using existing events should instead use the existing static final BUS field in the
+        // event class (for most events) or getBus(BusGroup) method (for mod bus events).
+        return EventBus.create(modEventBusGroup, eventClass);
+    }
 }

fmlcore/src/main/java/net/minecraftforge/fml/util/CertificateHelper.java

@@ -1,20 +1,6 @@
 /*
- * Minecraft Forge
- * Copyright (c) 2016-2021.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation version 2.1
- * of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
  */
 
 package net.minecraftforge.fml.util;