1.19.4 RB 2

Co-authored-by: malte0811 <[email protected]>

.teamcity/settings.kts

@@ -38,7 +38,7 @@ project {
     params {
         text("docker_jdk_version", "17", label = "Gradle version", description = "The version of the JDK to use during execution of tasks in a JDK.", display = ParameterDisplay.HIDDEN, allowEmpty = false)
         text("docker_gradle_version", "7.5.1", label = "Gradle version", description = "The version of Gradle to use during execution of Gradle tasks.", display = ParameterDisplay.HIDDEN, allowEmpty = false)
-        text("git_main_branch", "1.19.x", label = "Git Main Branch", description = "The git main or default branch to use in VCS operations.", display = ParameterDisplay.HIDDEN, allowEmpty = false)
+        text("git_main_branch", "1.20.x", label = "Git Main Branch", description = "The git main or default branch to use in VCS operations.", display = ParameterDisplay.HIDDEN, allowEmpty = false)
         text("git_branch_spec", """
                 +:refs/heads/(main*)
                 +:refs/heads/(master*)

build.gradle

@@ -27,8 +27,8 @@ plugins {
     id 'net.minecraftforge.gradleutils' version '2.+'
     id 'eclipse'
     id 'de.undercouch.download' version '5.1.3'
-    id 'net.minecraftforge.gradle.patcher' version '[5.1.50,5.2.0)' apply false
-    id 'net.minecraftforge.gradle.mcp' version '[5.1.50,5.2.0)' apply false
+    id 'net.minecraftforge.gradle.patcher' version '[5.1.77,5.2.0)' apply false
+    id 'net.minecraftforge.gradle.mcp' version '[5.1.77,5.2.0)' apply false
 }
 
 Util.init() //Init all our extension methods!
@@ -884,6 +884,10 @@ project(':forge') {
     apply plugin: 'net.minecraftforge.gradle.patcher'
     apply plugin: 'org.cadixdev.licenser'
 
+    applyPatches { 
+        level 'WARNING'
+    }
+
     sourceSets {
         main {
             java {

docs/README.md

@@ -10,8 +10,9 @@ Forge is a free, open-source modding API all of your favourite mods use!
 
 | Version |    Support    |
 |---------| ------------- |
-| 1.19.x  |    Active     |
-| 1.18.x  |    LTS        |
+| 1.20.x  |    Active     |
+| 1.19.4  |    Legacy     |
+| 1.19.2  |    Legacy     |
 
 * [Download]
 * [Forum]

fmlloader/src/main/java/net/minecraftforge/fml/loading/UniqueModListBuilder.java

@@ -11,11 +11,17 @@ import net.minecraftforge.forgespi.language.IModInfo;
 import org.apache.maven.artifact.versioning.ArtifactVersion;
 import org.slf4j.Logger;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.List;
+import java.util.Map;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
-import static java.util.stream.Collectors.*;
+import static java.util.stream.Collectors.groupingBy;
+import static java.util.stream.Collectors.joining;
+import static net.minecraftforge.fml.loading.LogMarkers.LOADING;
 
 public class UniqueModListBuilder
 {
@@ -66,28 +72,35 @@ public class UniqueModListBuilder
 
         // Its theoretically possible that some mod has somehow moved an id to a secondary place, thus causing a dupe.
         // We can't handle this
-        final List<IModInfo> dupedMods = modIds.values().stream()
+        final List<String> dupedModErrors = modIds.values().stream()
                 .filter(modInfos -> modInfos.size() > 1)
-                .map(modInfos -> modInfos.get(0))
-                .toList();
+                .map(mods -> String.format("\tMod ID: '%s' from mod files: %s",
+                        mods.get(0).getModId(),
+                        mods.stream()
+                                .map(modInfo -> modInfo.getOwningFile().getFile().getFileName()).collect(joining(", "))
+                )).toList();
 
-        if (!dupedMods.isEmpty()) {
-            final List<EarlyLoadingException.ExceptionData> duplicateModErrors = dupedMods.stream()
-                                                                                   .map(dm -> new EarlyLoadingException.ExceptionData("fml.modloading.dupedmod", dm, Objects.toString(dm)))
-                                                                                   .toList();
-            throw new EarlyLoadingException("Duplicate mods found", null,  duplicateModErrors);
+        if (!dupedModErrors.isEmpty()) {
+            LOGGER.error(LOADING, "Found duplicate mods:\n{}", dupedModErrors.stream().collect(joining("\n")));
+            throw new EarlyLoadingException("Duplicate mods found", null, dupedModErrors.stream()
+                    .map(s -> new EarlyLoadingException.ExceptionData(s))
+                    .toList());
         }
 
-        final List<ModFile> dupedLibs = versionedLibIds.values().stream()
-                .filter(modFiles -> modFiles.size() > 1)
-                .map(modFiles -> modFiles.get(0))
-                .toList();
 
-        if (!dupedLibs.isEmpty()) {
-            final List<EarlyLoadingException.ExceptionData> duplicateLibErrors = dupedLibs.stream()
-                .map(dm -> new EarlyLoadingException.ExceptionData("fml.modloading.dupedlib.versioned", dm, Objects.toString(dm)))
-                .toList();
-            throw new EarlyLoadingException("Duplicate plugins or libraries found", null,  duplicateLibErrors);
+        final List<String> dupedLibErrors = versionedLibIds.values().stream()
+                .filter(modFiles -> modFiles.size() > 1)
+                .map(mods -> String.format("\tLibrary: '%s' from files: %s",
+                        getModId(mods.get(0)),
+                        mods.stream()
+                                .map(modFile -> modFile.getFileName()).collect(joining(", "))
+                )).toList();
+
+        if (!dupedLibErrors.isEmpty()) {
+            LOGGER.error(LOADING, "Found duplicate plugins or libraries:\n{}", dupedLibErrors.stream().collect(joining("\n")));
+            throw new EarlyLoadingException("Duplicate plugins or libraries found", null, dupedLibErrors.stream()
+                    .map(s -> new EarlyLoadingException.ExceptionData(s))
+                    .toList());
         }
 
         // Collect unique mod files by module name. This will be used for deduping purposes

patches/minecraft/net/minecraft/client/KeyMapping.java.patch

@@ -12,6 +12,15 @@
     private static final Set<String> f_90811_ = Sets.newHashSet();
     public static final String f_167805_ = "key.categories.movement";
     public static final String f_167806_ = "key.categories.misc";
+@@ -41,7 +_,7 @@
+    private int f_90818_;
+ 
+    public static void m_90835_(InputConstants.Key p_90836_) {
+-      KeyMapping keymapping = f_90810_.get(p_90836_);
++      for (KeyMapping keymapping : f_90810_.getAll(p_90836_))
+       if (keymapping != null) {
+          ++keymapping.f_90818_;
+       }
 @@ -49,7 +_,7 @@
     }
  

patches/minecraft/net/minecraft/client/gui/screens/ConnectScreen.java.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/client/gui/screens/ConnectScreen.java
++++ b/net/minecraft/client/gui/screens/ConnectScreen.java
+@@ -72,6 +_,8 @@
+                }
+ 
+                if (!optional.isPresent()) {
++                  ConnectScreen.f_95683_.error("Couldn't connect to server: Unknown host \"{}\"", p_249536_.m_171863_());
++                  net.minecraftforge.network.DualStackUtils.logInitialPreferences();
+                   p_251955_.execute(() -> {
+                      p_251955_.m_91152_(new DisconnectedScreen(ConnectScreen.this.f_95686_, CommonComponents.f_130661_, ConnectScreen.f_169260_));
+                   });

patches/minecraft/net/minecraft/client/gui/screens/PauseScreen.java.patch

@@ -0,0 +1,10 @@
+--- a/net/minecraft/client/gui/screens/PauseScreen.java
++++ b/net/minecraft/client/gui/screens/PauseScreen.java
+@@ -83,6 +_,7 @@
+       } else {
+          gridlayout$rowhelper.m_264139_(this.m_262456_(f_262254_, SocialInteractionsScreen::new));
+       }
++      gridlayout$rowhelper.m_264108_(Button.m_253074_(Component.m_237115_("fml.menu.mods"), button -> this.f_96541_.m_91152_(new net.minecraftforge.client.gui.ModListScreen(this))).m_252780_(f_262268_).m_253136_(), 2);
+ 
+       Component component = this.f_96541_.m_91090_() ? f_262217_ : f_262246_;
+       this.f_252482_ = gridlayout$rowhelper.m_264108_(Button.m_253074_(component, (p_275864_) -> {

patches/minecraft/net/minecraft/client/gui/screens/advancements/AdvancementsScreen.java.patch

@@ -34,7 +34,7 @@
                 this.f_97334_.m_104401_(advancementtab.m_97182_(), true);
                 break;
              }
-@@ -98,6 +_,11 @@
+@@ -98,9 +_,15 @@
        int i = (this.f_96543_ - 252) / 2;
        int j = (this.f_96544_ - 140) / 2;
        this.m_7333_(p_97361_);
@@ -46,6 +46,10 @@
        this.m_97373_(p_97361_, p_97362_, p_97363_, i, j);
        this.m_97356_(p_97361_, i, j);
        this.m_97381_(p_97361_, p_97362_, p_97363_, i, j);
++      super.m_86412_(p_97361_, p_97362_, p_97363_, p_97364_);
+    }
+ 
+    public boolean m_7979_(double p_97347_, double p_97348_, int p_97349_, double p_97350_, double p_97351_) {
 @@ -138,10 +_,12 @@
           RenderSystem.m_157456_(0, f_97330_);
  

patches/minecraft/net/minecraft/client/particle/TerrainParticle.java.patch

@@ -1,5 +1,14 @@
 --- a/net/minecraft/client/particle/TerrainParticle.java
 +++ b/net/minecraft/client/particle/TerrainParticle.java
+@@ -28,7 +_,7 @@
+       this.f_107227_ = 0.6F;
+       this.f_107228_ = 0.6F;
+       this.f_107229_ = 0.6F;
+-      if (!p_172458_.m_60713_(Blocks.f_50440_)) {
++      if (net.minecraftforge.client.extensions.common.IClientBlockExtensions.of(p_172458_).areBreakingParticlesTinted(p_172458_, p_172451_, p_172459_)) {
+          int i = Minecraft.m_91087_().m_91298_().m_92577_(p_172458_, p_172451_, p_172459_, 0);
+          this.f_107227_ *= (float)(i >> 16 & 255) / 255.0F;
+          this.f_107228_ *= (float)(i >> 8 & 255) / 255.0F;
 @@ -69,7 +_,13 @@
     public static class Provider implements ParticleProvider<BlockParticleOption> {
        public Particle m_6966_(BlockParticleOption p_108304_, ClientLevel p_108305_, double p_108306_, double p_108307_, double p_108308_, double p_108309_, double p_108310_, double p_108311_) {

patches/minecraft/net/minecraft/client/server/LanServerDetection.java.patch

@@ -9,21 +9,13 @@
           this.f_120088_.setSoTimeout(5000);
           this.f_120088_.joinGroup(this.f_120087_);
        }
-@@ -87,7 +_,19 @@
+@@ -87,7 +_,11 @@
           String s = LanServerPinger.m_120111_(p_120097_);
           String s1 = LanServerPinger.m_120116_(p_120097_);
           if (s1 != null) {
 -            s1 = p_120098_.getHostAddress() + ":" + s1;
 +            if (net.minecraftforge.network.DualStackUtils.checkIPv6(p_120098_)) {
-+               final String ip;
-+
-+               // compress to short form if enabled in config
-+               if (net.minecraftforge.common.ForgeConfig.CLIENT.compressLanIPv6Addresses.get())
-+                  ip = com.google.common.net.InetAddresses.toAddrString(p_120098_);
-+               else
-+                  ip = p_120098_.getHostAddress();
-+
-+               s1 = "[" + ip + "]:" + s1;
++               s1 = "[" + com.google.common.net.InetAddresses.toAddrString(p_120098_) + "]:" + s1;
 +            } else {
 +               s1 = p_120098_.getHostAddress() + ":" + s1;
 +            }

patches/minecraft/net/minecraft/client/server/LanServerPinger.java.patch

@@ -1,6 +1,6 @@
 --- a/net/minecraft/client/server/LanServerPinger.java
 +++ b/net/minecraft/client/server/LanServerPinger.java
-@@ -16,7 +_,7 @@
+@@ -13,7 +_,7 @@
  public class LanServerPinger extends Thread {
     private static final AtomicInteger f_120101_ = new AtomicInteger(0);
     private static final Logger f_120102_ = LogUtils.getLogger();
@@ -9,7 +9,7 @@
     public static final int f_174975_ = 4445;
     private static final long f_174976_ = 1500L;
     private final String f_120103_;
-@@ -39,7 +_,7 @@
+@@ -36,7 +_,7 @@
  
        while(!this.isInterrupted() && this.f_120105_) {
           try {

patches/minecraft/net/minecraft/server/dedicated/DedicatedServer.java.patch

@@ -1,5 +1,14 @@
 --- a/net/minecraft/server/dedicated/DedicatedServer.java
 +++ b/net/minecraft/server/dedicated/DedicatedServer.java
+@@ -68,6 +_,8 @@
+    private MinecraftServerGui f_139605_;
+    @Nullable
+    private final TextFilterClient f_139606_;
++   @Nullable
++   private net.minecraft.client.server.LanServerPinger dediLanPinger;
+ 
+    public DedicatedServer(Thread p_214789_, LevelStorageSource.LevelStorageAccess p_214790_, PackRepository p_214791_, WorldStem p_214792_, DedicatedServerSettings p_214793_, DataFixer p_214794_, Services p_214795_, ChunkProgressListenerFactory p_214796_) {
+       super(p_214789_, p_214790_, p_214791_, p_214792_, Proxy.NO_PROXY, p_214794_, p_214795_, p_214796_);
 @@ -79,6 +_,7 @@
     public boolean m_7038_() throws IOException {
        Thread thread = new Thread("Server console handler") {
@@ -22,7 +31,7 @@
           if (dedicatedserverproperties.f_139744_ != null) {
              this.m_129900_().m_46170_(GameRules.f_46153_).m_46246_(dedicatedserverproperties.f_139744_, this);
           }
-@@ -183,12 +_,13 @@
+@@ -183,12 +_,18 @@
              thread1.start();
           }
  
@@ -33,7 +42,34 @@
           }
  
 -         return true;
++         if (net.minecraftforge.common.ForgeConfig.SERVER.advertiseDedicatedServerToLan.get()) {
++            this.dediLanPinger = new net.minecraft.client.server.LanServerPinger(this.m_129916_(), String.valueOf(this.m_7448_()));
++            this.dediLanPinger.start();
++         }
++
 +         return net.minecraftforge.server.ServerLifecycleHooks.handleServerStarting(this);
        }
     }
  
+@@ -263,6 +_,10 @@
+          this.f_139601_.m_7530_();
+       }
+ 
++      if (this.dediLanPinger != null) {
++         this.dediLanPinger.interrupt();
++         this.dediLanPinger = null;
++      }
+    }
+ 
+    public void m_5703_(BooleanSupplier p_139661_) {
+@@ -492,6 +_,10 @@
+ 
+    public void m_7041_() {
+       super.m_7041_();
++      if (this.dediLanPinger != null) {
++         this.dediLanPinger.interrupt();
++         this.dediLanPinger = null;
++      }
+       Util.m_137580_();
+       SkullBlockEntity.m_196704_();
+    }

patches/minecraft/net/minecraft/server/network/ServerLoginPacketListenerImpl.java.patch

@@ -15,6 +15,16 @@
           this.m_10055_();
        } else if (this.f_10019_ == ServerLoginPacketListenerImpl.State.DELAY_ACCEPT) {
           ServerPlayer serverplayer = this.f_10018_.m_6846_().m_11259_(this.f_10021_.getId());
+@@ -138,7 +_,8 @@
+    }
+ 
+    public String m_10056_() {
+-      return this.f_10021_ != null ? this.f_10021_ + " (" + this.f_10013_.m_129523_() + ")" : String.valueOf((Object)this.f_10013_.m_129523_());
++      final String addressString = net.minecraftforge.network.DualStackUtils.getAddressString(this.f_10013_.m_129523_());
++      return this.f_10021_ != null ? this.f_10021_ + " (" + addressString + ")" : addressString;
+    }
+ 
+    public void m_5990_(ServerboundHelloPacket p_10047_) {
 @@ -147,14 +_,14 @@
        GameProfile gameprofile = this.f_10018_.m_236731_();
        if (gameprofile != null && p_10047_.f_238040_().equalsIgnoreCase(gameprofile.getName())) {

patches/minecraft/net/minecraft/server/packs/repository/PackRepository.java.patch

@@ -5,7 +5,7 @@
  
     public PackRepository(RepositorySource... p_251886_) {
 -      this.f_10497_ = ImmutableSet.copyOf(p_251886_);
-+      this.f_10497_ = new java.util.HashSet<>(List.of(p_251886_)); //Forge: This needs to be a mutable set, so that we can add to it later on.
++      this.f_10497_ = new java.util.LinkedHashSet<>(List.of(p_251886_)); //Forge: This needs to be a mutable set, so that we can add to it later on.
     }
  
     public void m_10506_() {

patches/minecraft/net/minecraft/server/players/PlayerList.java.patch

@@ -8,7 +8,15 @@
  
     public PlayerList(MinecraftServer p_203842_, LayeredRegistryAccess<RegistryLayer> p_251844_, PlayerDataStorage p_203844_, int p_203845_) {
        this.f_11195_ = p_203842_;
-@@ -168,6 +_,7 @@
+@@ -161,13 +_,14 @@
+       p_11263_.m_143425_(serverlevel1);
+       String s1 = "local";
+       if (p_11262_.m_129523_() != null) {
+-         s1 = p_11262_.m_129523_().toString();
++         s1 = net.minecraftforge.network.DualStackUtils.getAddressString(p_11262_.m_129523_());
+       }
+ 
+       f_11188_.info("{}[{}] logged in with entity id {} at ({}, {}, {})", p_11263_.m_7755_().getString(), s1, p_11263_.m_19879_(), p_11263_.m_20185_(), p_11263_.m_20186_(), p_11263_.m_20189_());
        LevelData leveldata = serverlevel1.m_6106_();
        p_11263_.m_143427_(compoundtag);
        ServerGamePacketListenerImpl servergamepacketlistenerimpl = new ServerGamePacketListenerImpl(this.f_11195_, p_11262_, p_11263_);

patches/minecraft/net/minecraft/world/entity/Entity.java.patch

@@ -160,7 +160,7 @@
           this.m_5496_(soundtype.m_56776_(), soundtype.m_56773_() * 0.15F, soundtype.m_56774_());
        }
     }
-@@ -1074,19 +_,22 @@
+@@ -1074,31 +_,38 @@
  
     public void m_5844_() {
        if (this.m_6069_()) {
@@ -188,6 +188,24 @@
     }
  
     void m_20074_() {
+       Entity entity = this.m_20202_();
++      java.util.function.BooleanSupplier updateFluidHeight = () -> this.m_204031_(FluidTags.f_13131_, 0.014D);
+       if (entity instanceof Boat boat) {
+          if (!boat.m_5842_()) {
+             this.f_19798_ = false;
+-            return;
++            updateFluidHeight = () -> {
++               this.updateFluidHeightAndDoFluidPushing(state -> this.shouldUpdateFluidWhileBoating(state, boat));
++               return false;
++            };
+          }
+       }
+ 
+-      if (this.m_204031_(FluidTags.f_13131_, 0.014D)) {
++      if (updateFluidHeight.getAsBoolean()) {
+          if (!this.f_19798_ && !this.f_19803_) {
+             this.m_5841_();
+          }
 @@ -1115,6 +_,7 @@
     private void m_20323_() {
        this.f_19800_ = this.m_204029_(FluidTags.f_13131_);
@@ -414,19 +432,24 @@
           });
        }
  
-@@ -2861,9 +_,17 @@
+@@ -2861,9 +_,22 @@
        this.f_19859_ = this.m_146908_();
     }
  
-+   @Deprecated // Forge: Use no parameter version instead, only for vanilla Tags
++   @Deprecated // Forge: Use predicate version instead, only for vanilla Tags
     public boolean m_204031_(TagKey<Fluid> p_204032_, double p_204033_) {
-+      this.updateFluidHeightAndDoFluidPushing();
++      this.updateFluidHeightAndDoFluidPushing(com.google.common.base.Predicates.alwaysTrue());
 +      if(p_204032_ == FluidTags.f_13131_) return this.isInFluidType(net.minecraftforge.common.ForgeMod.WATER_TYPE.get());
 +      else if (p_204032_ == FluidTags.f_13132_) return this.isInFluidType(net.minecraftforge.common.ForgeMod.LAVA_TYPE.get());
 +      else return false;
 +   }
 +
++   @Deprecated(forRemoval = true, since = "1.19.4")
 +   public void updateFluidHeightAndDoFluidPushing() {
++      this.updateFluidHeightAndDoFluidPushing(com.google.common.base.Predicates.alwaysTrue());
++   }
++
++   public void updateFluidHeightAndDoFluidPushing(Predicate<FluidState> shouldUpdate) {
        if (this.m_146899_()) {
 -         return false;
 +         return;
@@ -446,7 +469,7 @@
                    FluidState fluidstate = this.f_19853_.m_6425_(blockpos$mutableblockpos);
 -                  if (fluidstate.m_205070_(p_204032_)) {
 +                  net.minecraftforge.fluids.FluidType fluidType = fluidstate.getFluidType();
-+                  if (!fluidType.isAir()) {
++                  if (!fluidType.isAir() && shouldUpdate.test(fluidstate)) {
                       double d1 = (double)((float)i2 + fluidstate.m_76155_(this.f_19853_, blockpos$mutableblockpos));
                       if (d1 >= aabb.f_82289_) {
                          flag1 = true;

patches/minecraft/net/minecraft/world/level/levelgen/feature/treedecorators/AlterGroundDecorator.java.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/level/levelgen/feature/treedecorators/AlterGroundDecorator.java
++++ b/net/minecraft/world/level/levelgen/feature/treedecorators/AlterGroundDecorator.java
+@@ -72,7 +_,7 @@
+       for(int i = 2; i >= -3; --i) {
+          BlockPos blockpos = p_225975_.m_6630_(i);
+          if (Feature.m_65788_(p_225974_.m_226058_(), blockpos)) {
+-            p_225974_.m_226061_(blockpos, this.f_69303_.m_213972_(p_225974_.m_226067_(), p_225975_));
++            p_225974_.m_226061_(blockpos, net.minecraftforge.event.ForgeEventFactory.alterGround(p_225974_.m_226058_(), p_225974_.m_226067_(), blockpos, this.f_69303_.m_213972_(p_225974_.m_226067_(), p_225975_)));
+             break;
+          }
+ 

src/generated_test/resources/assets/minecraft/particles/cloud.json

@@ -0,0 +1,12 @@
+{
+  "textures": [
+    "minecraft:generic_7",
+    "minecraft:generic_6",
+    "minecraft:generic_5",
+    "minecraft:generic_4",
+    "minecraft:generic_3",
+    "minecraft:generic_2",
+    "minecraft:generic_1",
+    "minecraft:generic_0"
+  ]
+}

src/generated_test/resources/assets/minecraft/particles/dripping_lava.json

@@ -0,0 +1,5 @@
+{
+  "textures": [
+    "minecraft:drip_hang"
+  ]
+}

src/generated_test/resources/assets/minecraft/particles/enchant.json

@@ -0,0 +1,30 @@
+{
+  "textures": [
+    "minecraft:sga_a",
+    "minecraft:sga_b",
+    "minecraft:sga_c",
+    "minecraft:sga_d",
+    "minecraft:sga_e",
+    "minecraft:sga_f",
+    "minecraft:sga_g",
+    "minecraft:sga_h",
+    "minecraft:sga_i",
+    "minecraft:sga_j",
+    "minecraft:sga_k",
+    "minecraft:sga_l",
+    "minecraft:sga_m",
+    "minecraft:sga_n",
+    "minecraft:sga_o",
+    "minecraft:sga_p",
+    "minecraft:sga_q",
+    "minecraft:sga_r",
+    "minecraft:sga_s",
+    "minecraft:sga_t",
+    "minecraft:sga_u",
+    "minecraft:sga_v",
+    "minecraft:sga_w",
+    "minecraft:sga_x",
+    "minecraft:sga_y",
+    "minecraft:sga_z"
+  ]
+}

src/generated_test/resources/assets/minecraft/particles/fishing.json

@@ -0,0 +1,8 @@
+{
+  "textures": [
+    "minecraft:splash_0",
+    "minecraft:splash_1",
+    "minecraft:splash_2",
+    "minecraft:splash_3"
+  ]
+}

src/main/java/net/minecraftforge/client/extensions/IForgeDimensionSpecialEffects.java

@@ -67,15 +67,15 @@ public interface IForgeDimensionSpecialEffects
      * Allows for manipulating the coloring of the lightmap texture.
      * Will be called for each 16*16 combination of sky/block light values.
      *
-     * @param level        The current level (client-side).
-     * @param partialTicks Progress between ticks.
-     * @param skyDarken    Current darkness of the sky.
-     * @param skyLight     Sky light brightness factor.
-     * @param blockLight   Block light brightness factor.
-     * @param pixelX       X-coordinate of the lightmap texture.
-     * @param pixelY       Y-coordinate of the lightmap texture.
-     * @param colors       The color values that will be used: [r, g, b].
+     * @param level                The current level (client-side).
+     * @param partialTicks         Progress between ticks.
+     * @param skyDarken            Current darkness of the sky (can be used to calculate sky light).
+     * @param blockLightRedFlicker Block light flicker factor (red color) (can be used to calculate block light).
+     * @param skyLight             Sky light brightness (accounting for sky darkness).
+     * @param pixelX               X-coordinate of the lightmap texture (block).
+     * @param pixelY               Y-coordinate of the lightmap texture (sky).
+     * @param colors               The color values that will be used: [r, g, b].
      * @see LightTexture#updateLightTexture(float)
      */
-    default void adjustLightmapColors(ClientLevel level, float partialTicks, float skyDarken, float skyLight, float blockLight, int pixelX, int pixelY, Vector3f colors) {}
+    default void adjustLightmapColors(ClientLevel level, float partialTicks, float skyDarken, float blockLightRedFlicker, float skyLight, int pixelX, int pixelY, Vector3f colors) {}
 }

src/main/java/net/minecraftforge/client/extensions/common/IClientBlockExtensions.java

@@ -5,6 +5,7 @@
 
 package net.minecraftforge.client.extensions.common;
 
+import net.minecraft.client.multiplayer.ClientLevel;
 import net.minecraft.client.particle.ParticleEngine;
 import net.minecraft.core.BlockPos;
 import net.minecraft.world.effect.MobEffects;
@@ -14,6 +15,7 @@ import net.minecraft.world.item.enchantment.EnchantmentHelper;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.LevelReader;
 import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.material.Material;
 import net.minecraft.world.phys.HitResult;
@@ -111,4 +113,17 @@ public interface IClientBlockExtensions
         }
         return originalColor;
     }
+
+    /**
+     * Returns true if the breaking particles created from the {@link BlockState} passed should be tinted with biome colors. 
+     * 
+     * @param state The state of this block
+     * @param level The level the particles are spawning in
+     * @param pos The position of the block
+     * @return {@code true} if the particles should be tinted.
+     */
+    default boolean areBreakingParticlesTinted(BlockState state, ClientLevel level, BlockPos pos)
+    {
+        return !state.is(Blocks.GRASS_BLOCK);
+    }
 }

src/main/java/net/minecraftforge/client/gui/overlay/ForgeGui.java

@@ -496,6 +496,13 @@ public class ForgeGui extends Gui
         }
     }
 
+    @Override
+    public void clearCache()
+    {
+        super.clearCache();
+        this.debugOverlay.clearChunkCache();
+    }
+
     protected void renderRecordOverlay(int width, int height, float partialTick, PoseStack pStack)
     {
         if (overlayMessageTime > 0)

src/main/java/net/minecraftforge/client/settings/KeyMappingLookup.java

@@ -27,6 +27,7 @@ public class KeyMappingLookup
         }
     }
 
+    @Deprecated(forRemoval = true)
     @Nullable
     public KeyMapping get(InputConstants.Key keyCode)
     {
@@ -59,6 +60,16 @@ public class KeyMappingLookup
         return null;
     }
 
+    /**
+     * Returns all active keys associated with the given key code and the active
+     * modifiers and conflict context.
+     *
+     * This could probably be renamed to something like getActiveMappings, but
+     * that would be a breaking change.
+     *
+     * @param keyCode the key being pressed
+     * @return the list of key mappings
+     */
     public List<KeyMapping> getAll(InputConstants.Key keyCode)
     {
         List<KeyMapping> matchingBindings = new ArrayList<KeyMapping>();
@@ -67,7 +78,11 @@ public class KeyMappingLookup
             Collection<KeyMapping> bindings = bindingsMap.get(keyCode);
             if (bindings != null)
             {
-                matchingBindings.addAll(bindings);
+                for (KeyMapping binding : bindings)
+                {
+                    if (binding.isConflictContextAndModifierActive())
+                        matchingBindings.add(binding);
+                }
             }
         }
         return matchingBindings;

src/main/java/net/minecraftforge/common/ForgeConfig.java

@@ -30,6 +30,8 @@ public class ForgeConfig {
 
         public final ConfigValue<String> permissionHandler;
 
+        public final BooleanValue advertiseDedicatedServerToLan;
+
         Server(ForgeConfigSpec.Builder builder) {
             builder.comment("Server configuration settings")
                    .push("server");
@@ -69,6 +71,11 @@ public class ForgeConfig {
                     .translation("forge.configgui.permissionHandler")
                     .define("permissionHandler", "forge:default_handler");
 
+            advertiseDedicatedServerToLan = builder
+                    .comment("Set this to true to enable advertising the dedicated server to local LAN clients so that it shows up in the Multiplayer screen automatically.")
+                    .translation("forge.configgui.advertiseDedicatedServerToLan")
+                    .define("advertiseDedicatedServerToLan", true);
+
             builder.pop();
         }
     }
@@ -123,6 +130,7 @@ public class ForgeConfig {
 
         public final BooleanValue useCombinedDepthStencilAttachment;
 
+        @Deprecated(since = "1.20.1", forRemoval = true) // Config option ignored.
         public final BooleanValue compressLanIPv6Addresses;
 
         Client(ForgeConfigSpec.Builder builder) {
@@ -152,7 +160,7 @@ public class ForgeConfig {
                     .define("useCombinedDepthStencilAttachment", false);
 
             compressLanIPv6Addresses = builder
-                    .comment("When enabled, Forge will convert discovered 'Open to LAN' IPv6 addresses to their more compact, compressed representation")
+                    .comment("[DEPRECATED] [NOW IN COMMON CONFIG] When enabled, Forge will convert discovered 'Open to LAN' IPv6 addresses to their more compact, compressed representation")
                     .translation("forge.configgui.compressLanIPv6Addresses")
                     .define("compressLanIPv6Addresses", true);
 

src/main/java/net/minecraftforge/common/MinecraftForge.java

@@ -10,6 +10,7 @@ import net.minecraftforge.client.ClientCommandHandler;
 import net.minecraftforge.eventbus.api.BusBuilder;
 import net.minecraftforge.eventbus.api.IEventBus;
 import net.minecraftforge.fml.loading.FMLEnvironment;
+import net.minecraftforge.network.DualStackUtils;
 import net.minecraftforge.versions.forge.ForgeVersion;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -42,6 +43,7 @@ public class MinecraftForge
        UsernameCache.load();
        TierSortingRegistry.init();
        if (FMLEnvironment.dist == Dist.CLIENT) ClientCommandHandler.init();
+       DualStackUtils.initialise();
    }
 
 /*

src/main/java/net/minecraftforge/common/data/ParticleDescriptionProvider.java

@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.common.data;
+
+import com.google.common.base.Preconditions;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonObject;
+import net.minecraft.Util;
+import net.minecraft.client.particle.ParticleEngine;
+import net.minecraft.client.particle.ParticleProvider;
+import net.minecraft.core.particles.ParticleType;
+import net.minecraft.data.CachedOutput;
+import net.minecraft.data.DataProvider;
+import net.minecraft.data.PackOutput;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.packs.PackType;
+import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
+import net.minecraftforge.registries.ForgeRegistries;
+import org.jetbrains.annotations.VisibleForTesting;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.Stream;
+
+/**
+ * A data provider for {@link net.minecraft.client.particle.ParticleDescription}s.
+ *
+ * <p>To use this provider, extend this class and implement {@link #addDescriptions()}.
+ * Then, register an instance using {@link net.minecraft.data.DataGenerator#addProvider(boolean, Factory)}
+ * via the {@link net.minecraftforge.data.event.GatherDataEvent} on the {@linkplain FMLJavaModLoadingContext#getModEventBus() mod event bus}.
+ *
+ * <p>A description can be added to a {@link ParticleType} which uses a {@linkplain #sprite(ParticleType, ResourceLocation) sprite}
+ * or {@linkplain #spriteSet(ParticleType, Iterable) sprite set}.
+ *
+ * <pre>{@code
+ * @Override
+ * protected void addDescriptions() {
+ *     // Single sprite
+ *     this.sprite(ParticleTypes.DRIPPING_LAVA, new ResourceLocation("drip_hang"));
+ *
+ *     // Multiple sprites
+ *     this.spriteSet(ParticleTypes.CLOUD, new ResourceLocation("generic"), 8, true);
+ * }
+ * }</pre>
+ *
+ * <p>A particle description holds a list of textures used when rendering the
+ * particle to the screen. All registered particle descriptions are stitched
+ * together into a texture atlas called {@link net.minecraft.client.renderer.texture.TextureAtlas#LOCATION_PARTICLES}.
+ * A {@link ParticleType} whose particle uses the texture atlas, typically via
+ * the {@link net.minecraft.client.particle.ParticleRenderType}, can then reference
+ * the necessary texture during rendering.
+ *
+ * <p>Particles with a particle description must have their particle providers
+ * attached to a {@link ParticleType} as a {@linkplain net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSprite(ParticleType, ParticleProvider.Sprite) sprite}
+ * or {@linkplain net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSpriteSet(ParticleType, ParticleEngine.SpriteParticleRegistration) sprite set}
+ * consumer.
+ *
+ * @see DataProvider
+ * @see net.minecraft.client.particle.ParticleDescription
+ */
+public abstract class ParticleDescriptionProvider implements DataProvider {
+
+    private final PackOutput.PathProvider particlesPath;
+    @VisibleForTesting
+    protected final ExistingFileHelper fileHelper;
+    @VisibleForTesting
+    protected final Map<ResourceLocation, List<String>> descriptions;
+
+    /**
+     * Creates an instance of the data provider.
+     *
+     * @param output the expected root directory the data generator outputs to
+     * @param fileHelper the helper used to validate a texture's existence
+     */
+    protected ParticleDescriptionProvider(PackOutput output, ExistingFileHelper fileHelper) {
+        this.particlesPath = output.createPathProvider(PackOutput.Target.RESOURCE_PACK, "particles");
+        this.fileHelper = fileHelper;
+        this.descriptions = new HashMap<>();
+    }
+
+    /**
+     * Registers the particle descriptions generated by {@link #sprite(ParticleType, ResourceLocation)}
+     * or one of the {@link #spriteSet(ParticleType, Iterable) sprite set methods}.
+     */
+    protected abstract void addDescriptions();
+
+    /**
+     * Creates a new particle description that contains a single texture for the
+     * associated {@link ParticleType}.
+     *
+     * <p>Particle types with this description should be attached to a particle provider
+     * via {@link net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSprite(ParticleType, ParticleProvider.Sprite)}.
+     *
+     * @param type                      the particle type the textures are applied
+     *                                  for
+     * @param texture                   the texture to render for the particle type
+     * @throws NullPointerException     if the particle type is not registered
+     * @throws IllegalArgumentException if a texture does not have an associated PNG
+     *                                  file, or the particle type has already been
+     *                                  provided
+     */
+    protected void sprite(ParticleType<?> type, ResourceLocation texture) {
+        this.spriteSet(type, texture);
+    }
+
+    /**
+     * Creates a new particle description that contains multiple textures for the
+     * associated {@link ParticleType}. The textures are generated from a common
+     * name and appended with a number representing the state of the animation.
+     *
+     * <pre>{@code
+     * minecraft:generic_0
+     * minecraft:generic_1
+     * minecraft:generic_2
+     * // ...
+     * }</pre>
+     *
+     * <p>Particle types with this description should be attached to a particle provider
+     * via {@link net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSpriteSet(ParticleType, ParticleEngine.SpriteParticleRegistration)}.
+     *
+     * @param type                      the particle type the textures are applied
+     *                                  for
+     * @param baseName                  the common name of all the textures
+     * @param numOfTextures             the number of textures within the set
+     * @param reverse                   when {@code true}, the textures will be
+     *                                  listed in descending order
+     * @throws NullPointerException     if the particle type is not registered
+     * @throws IllegalArgumentException if a texture does not have an associated PNG
+     *                                  file, or the particle type has already been
+     *                                  provided
+     */
+    protected void spriteSet(ParticleType<?> type, ResourceLocation baseName, int numOfTextures, boolean reverse) {
+        Preconditions.checkArgument(numOfTextures > 0, "The number of textures to generate must be positive");
+        this.spriteSet(type, () -> new Iterator<>() {
+
+            private int counter = 0;
+
+            @Override
+            public boolean hasNext() {
+                return this.counter < numOfTextures;
+            }
+
+            @Override
+            public ResourceLocation next() {
+                var texture = baseName.withSuffix("_" + (reverse ? numOfTextures - this.counter - 1 : this.counter));
+                this.counter++;
+                return texture;
+            }
+        });
+    }
+
+    /**
+     * Creates a new particle description that contains multiple textures for the
+     * associated {@link ParticleType}. The textures are passed as varargs with
+     * at least one texture present.
+     *
+     * <p>Particle types with this description should be attached to a particle provider
+     * via {@link net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSpriteSet(ParticleType, ParticleEngine.SpriteParticleRegistration)}.
+     *
+     * @param type                      the particle type the textures are applied
+     *                                  for
+     * @param texture                   the first texture in the description
+     * @param textures                  a list of subsequent textures to render for
+     *                                  the particle type
+     * @throws NullPointerException     if the particle type is not registered
+     * @throws IllegalArgumentException if a texture does not have an associated PNG
+     *                                  file, or the particle type has already been
+     *                                  provided
+     */
+    protected void spriteSet(ParticleType<?> type, ResourceLocation texture, ResourceLocation... textures) {
+        this.spriteSet(type, Stream.concat(Stream.of(texture), Arrays.stream(textures))::iterator);
+    }
+
+    /**
+     * Creates a new particle description that contains multiple textures for the
+     * associated {@link ParticleType}. The textures are passed as an iterable.
+     *
+     * <p>Particle types with this description should be attached to a particle provider
+     * via {@link net.minecraftforge.client.event.RegisterParticleProvidersEvent#registerSpriteSet(ParticleType, ParticleEngine.SpriteParticleRegistration)}.
+     *
+     * @param type                      the particle type the textures are applied
+     *                                  for
+     * @param textures                  a list of textures to render for the
+     *                                  particle type
+     * @throws NullPointerException     if the particle type is not registered
+     * @throws IllegalArgumentException if there are no textures provided, a texture
+     *                                  does not have an associated PNG file, or
+     *                                  the particle type has already been provided
+     */
+    protected void spriteSet(ParticleType<?> type, Iterable<ResourceLocation> textures) {
+        // Make sure particle type is registered
+        var particle = Preconditions.checkNotNull(ForgeRegistries.PARTICLE_TYPES.getKey(type), "The particle type is not registered");
+
+        // Validate textures
+        List<String> desc = new ArrayList<>();
+        for (var texture : textures) {
+            Preconditions.checkArgument(this.fileHelper.exists(texture, PackType.CLIENT_RESOURCES, ".png", "textures/particle"),
+                    "Texture '%s' does not exist in any known resource pack", texture);
+            desc.add(texture.toString());
+        }
+        Preconditions.checkArgument(desc.size() > 0, "The particle type '%s' must have one texture", particle);
+
+        // Insert into map
+        if (this.descriptions.putIfAbsent(particle, desc) != null) {
+            throw new IllegalArgumentException(String.format("The particle type '%s' already has a description associated with it", particle));
+        }
+    }
+
+    @Override
+    public CompletableFuture<?> run(CachedOutput cache) {
+        this.addDescriptions();
+
+        return CompletableFuture.allOf(
+                this.descriptions.entrySet().stream().map(entry -> {
+                    // Map entries to the description format
+                    var textures = new JsonArray();
+                    entry.getValue().forEach(textures::add);
+                    return DataProvider.saveStable(cache,
+                            Util.make(new JsonObject(), obj -> obj.add("textures", textures)),
+                            this.particlesPath.json(entry.getKey())
+                    );
+                }).toArray(CompletableFuture[]::new)
+        );
+    }
+
+    @Override
+    public String getName() {
+        return "Particle Descriptions";
+    }
+}

src/main/java/net/minecraftforge/common/extensions/IForgeBoat.java

@@ -5,6 +5,7 @@
 
 package net.minecraftforge.common.extensions;
 
+import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.vehicle.Boat;
 import net.minecraft.world.level.material.FluidState;
 import net.minecraftforge.fluids.FluidType;
@@ -37,4 +38,17 @@ public interface IForgeBoat
     {
         return type.supportsBoating(self());
     }
+
+    /**
+     * When {@code false}, the fluid will no longer update its height value while
+     * within a boat while it is not within a fluid ({@link Boat#isUnderWater()}.
+     *
+     * @param state the state of the fluid the rider is within
+     * @param rider the rider of the boat
+     * @return {@code true} if the fluid height should be updated, {@code false} otherwise
+     */
+    default boolean shouldUpdateFluidWhileRiding(FluidState state, Entity rider)
+    {
+        return state.shouldUpdateWhileBoating(self(), rider);
+    }
 }

src/main/java/net/minecraftforge/common/extensions/IForgeEntity.java

@@ -13,6 +13,7 @@ import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.ai.attributes.AttributeInstance;
 import net.minecraft.world.entity.boss.enderdragon.EnderDragon;
 import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.entity.vehicle.Boat;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.entity.Entity;
@@ -424,4 +425,17 @@ public interface IForgeEntity extends ICapabilitySerializable<CompoundTag>
     {
         return false;
     }
+
+    /**
+     * When {@code false}, the fluid will no longer update its height value while
+     * within a boat while it is not within a fluid ({@link Boat#isUnderWater()}.
+     *
+     * @param state the state of the fluid the rider is within
+     * @param boat the boat the rider is within that is not inside a fluid
+     * @return {@code true} if the fluid height should be updated, {@code false} otherwise
+     */
+    default boolean shouldUpdateFluidWhileBoating(FluidState state, Boat boat)
+    {
+        return boat.shouldUpdateFluidWhileRiding(state, self());
+    }
 }

src/main/java/net/minecraftforge/common/extensions/IForgeFluid.java

@@ -6,6 +6,7 @@
 package net.minecraftforge.common.extensions;
 
 import net.minecraft.core.BlockPos;
+import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.Mob;
 import net.minecraft.world.entity.vehicle.Boat;
@@ -94,6 +95,20 @@ public interface IForgeFluid
         return getFluidType().supportsBoating(state, boat);
     }
 
+    /**
+     * When {@code false}, the fluid will no longer update its height value while
+     * within a boat while it is not within a fluid ({@link Boat#isUnderWater()}.
+     *
+     * @param state the state of the fluid the rider is within
+     * @param boat the boat the rider is within that is not inside a fluid
+     * @param rider the rider of the boat
+     * @return {@code true} if the fluid height should be updated, {@code false} otherwise
+     */
+    default boolean shouldUpdateWhileBoating(FluidState state, Boat boat, Entity rider)
+    {
+        return getFluidType().shouldUpdateWhileBoating(state, boat, rider);
+    }
+
     /**
      * Gets the path type of this fluid when an entity is pathfinding. When
      * {@code null}, uses vanilla behavior.

src/main/java/net/minecraftforge/common/extensions/IForgeFluidState.java

@@ -6,6 +6,7 @@
 package net.minecraftforge.common.extensions;
 
 import net.minecraft.core.BlockPos;
+import net.minecraft.world.entity.Entity;
 import net.minecraft.world.entity.LivingEntity;
 import net.minecraft.world.entity.Mob;
 import net.minecraft.world.entity.vehicle.Boat;
@@ -88,6 +89,19 @@ public interface IForgeFluidState
         return self().getType().supportsBoating(self(), boat);
     }
 
+    /**
+     * When {@code false}, the fluid will no longer update its height value while
+     * within a boat while it is not within a fluid ({@link Boat#isUnderWater()}.
+     *
+     * @param boat the boat the rider is within that is not inside a fluid
+     * @param rider the rider of the boat
+     * @return {@code true} if the fluid height should be updated, {@code false} otherwise
+     */
+    default boolean shouldUpdateWhileBoating(Boat boat, Entity rider)
+    {
+        return self().getType().shouldUpdateWhileBoating(self(), boat, rider);
+    }
+
     /**
      * Gets the path type of this fluid when an entity is pathfinding. When
      * {@code null}, uses vanilla behavior.

src/main/java/net/minecraftforge/energy/EmptyEnergyStorage.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.energy;
+
+/**
+ * Implementation of {@link IEnergyStorage} that cannot store, receive, or provide energy.
+ * Use the {@link #INSTANCE}, don't instantiate. Example:
+ * <pre>{@code
+ * ItemStack stack = ...;
+ * IEnergyStorage storage = stack.getCapability(ForgeCapabilities.ENERGY).orElse(EmptyEnergyStorage.INSTANCE);
+ * // Use storage without checking whether it's present.
+ * }</pre>
+ */
+public class EmptyEnergyStorage implements IEnergyStorage
+{
+    public static final EmptyEnergyStorage INSTANCE = new EmptyEnergyStorage();
+
+    protected EmptyEnergyStorage() {}
+
+    @Override
+    public int receiveEnergy(int maxReceive, boolean simulate)
+    {
+        return 0;
+    }
+
+    @Override
+    public int extractEnergy(int maxExtract, boolean simulate)
+    {
+        return 0;
+    }
+
+    @Override
+    public int getEnergyStored()
+    {
+        return 0;
+    }
+
+    @Override
+    public int getMaxEnergyStored()
+    {
+        return 0;
+    }
+
+    @Override
+    public boolean canExtract()
+    {
+        return false;
+    }
+
+    @Override
+    public boolean canReceive()
+    {
+        return false;
+    }
+}

src/main/java/net/minecraftforge/event/ForgeEventFactory.java

@@ -29,6 +29,7 @@ import net.minecraft.world.DifficultyInstance;
 import net.minecraft.world.entity.MobCategory;
 import net.minecraft.world.entity.projectile.Projectile;
 import net.minecraft.world.entity.projectile.ThrownEnderpearl;
+import net.minecraft.world.level.LevelSimulatedReader;
 import net.minecraft.world.level.biome.MobSpawnSettings;
 import net.minecraft.world.level.chunk.LevelChunk;
 import net.minecraft.world.level.levelgen.feature.ConfiguredFeature;
@@ -125,6 +126,7 @@ import net.minecraftforge.event.entity.player.PlayerWakeUpEvent;
 import net.minecraftforge.event.entity.player.SleepingLocationCheckEvent;
 import net.minecraftforge.event.entity.player.SleepingTimeCheckEvent;
 import net.minecraftforge.event.furnace.FurnaceFuelBurnTimeEvent;
+import net.minecraftforge.event.level.AlterGroundEvent;
 import net.minecraftforge.event.level.BlockEvent;
 import net.minecraftforge.event.level.BlockEvent.BlockToolModificationEvent;
 import net.minecraftforge.event.level.BlockEvent.CreateFluidSourceEvent;
@@ -680,6 +682,13 @@ public class ForgeEventFactory
         return event;
     }
 
+    public static BlockState alterGround(LevelSimulatedReader level, RandomSource random, BlockPos pos, BlockState altered)
+    {
+        AlterGroundEvent event = new AlterGroundEvent(level, random, pos, altered);
+        MinecraftForge.EVENT_BUS.post(event);
+        return event.getNewAlteredState();
+    }
+
     public static void fireChunkTicketLevelUpdated(ServerLevel level, long chunkPos, int oldTicketLevel, int newTicketLevel, @Nullable ChunkHolder chunkHolder)
     {
         if (oldTicketLevel != newTicketLevel)

src/main/java/net/minecraftforge/event/level/AlterGroundEvent.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.event.level;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.util.RandomSource;
+import net.minecraft.world.level.LevelSimulatedReader;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.level.levelgen.feature.treedecorators.TreeDecorator;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.eventbus.api.Cancelable;
+import net.minecraftforge.eventbus.api.Event;
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * This event is fired when {@link net.minecraft.world.level.levelgen.feature.treedecorators.AlterGroundDecorator#placeBlockAt(TreeDecorator.Context, BlockPos)}
+ * attempts to alter a ground block when generating a feature. An example of this would be large spruce trees converting grass blocks into podzol.
+ * <p>
+ * This event is not {@linkplain Cancelable cancellable}.
+ * <p>
+ * This event is fired on the {@linkplain MinecraftForge#EVENT_BUS main Forge event bus}
+ * only on the {@linkplain net.minecraftforge.fml.LogicalSide#SERVER logical server}.
+ */
+public class AlterGroundEvent extends Event {
+    private final LevelSimulatedReader level;
+    private final RandomSource random;
+    private final BlockPos pos;
+    private final BlockState originalAltered;
+    private BlockState newAltered;
+
+    @ApiStatus.Internal
+    public AlterGroundEvent(LevelSimulatedReader level, RandomSource random, BlockPos pos, BlockState altered) {
+        super();
+        this.level = level;
+        this.random = random;
+        this.pos = pos;
+        this.originalAltered = altered;
+        this.newAltered = altered;
+    }
+
+    public LevelSimulatedReader getLevel() {
+        return this.level;
+    }
+
+    public RandomSource getRandom() {
+        return this.random;
+    }
+
+    /**
+     * {@return the position of the block that will be altered}
+     */
+    public BlockPos getPos() {
+        return this.pos;
+    }
+
+    /**
+     * {@return the original block state that would be placed by the ground decorator}
+     */
+    public BlockState getOriginalAlteredState() {
+        return this.originalAltered;
+    }
+
+    /**
+     * {@return the new block state to be placed by the ground decorator}
+     */
+    public BlockState getNewAlteredState() {
+        return this.newAltered;
+    }
+
+    /**
+     * @param newAltered the new block state to be placed by the ground decorator
+     */
+    public void setNewAlteredState(BlockState newAltered) {
+        this.newAltered = newAltered;
+    }
+}

src/main/java/net/minecraftforge/fluids/FluidType.java

@@ -355,6 +355,20 @@ public class FluidType
         return this.supportsBoating(boat);
     }
 
+    /**
+     * When {@code false}, the fluid will no longer update its height value while
+     * within a boat while it is not within a fluid ({@link Boat#isUnderWater()}.
+     *
+     * @param state the state of the fluid the rider is within
+     * @param boat the boat the rider is within that is not inside a fluid
+     * @param rider the rider of the boat
+     * @return {@code true} if the fluid height should be updated, {@code false} otherwise
+     */
+    public boolean shouldUpdateWhileBoating(FluidState state, Boat boat, Entity rider)
+    {
+        return !this.supportsBoating(state, boat);
+    }
+
     /**
      * Returns whether the entity can ride in this vehicle under the fluid.
      *

src/main/java/net/minecraftforge/fluids/FluidUtil.java

@@ -147,7 +147,9 @@ public class FluidUtil
                         }
                         else
                         {
-                            containerFluidHandler.fill(simulatedTransfer, IFluidHandler.FluidAction.SIMULATE);
+                            // We are acting on a COPY of the stack, so performing changes on the source is acceptable even if we are simulating.
+                            // We need to perform the change otherwise the call to getContainer() will be incorrect.
+                            containerFluidHandler.fill(simulatedTransfer, IFluidHandler.FluidAction.EXECUTE);
                         }
 
                         ItemStack resultContainer = containerFluidHandler.getContainer();

src/main/java/net/minecraftforge/fluids/capability/wrappers/BlockWrapper.java

@@ -15,8 +15,6 @@ import net.minecraftforge.fluids.FluidType;
 import net.minecraftforge.fluids.FluidUtil;
 import net.minecraftforge.fluids.capability.templates.VoidFluidHandler;
 
-import net.minecraftforge.fluids.capability.IFluidHandler.FluidAction;
-
 /**
  * Wrapper around any block, only accounts for fluid placement, otherwise the block acts a void.
  * If the block in question inherits from the Forge implementations,
@@ -73,11 +71,11 @@ public class BlockWrapper extends VoidFluidHandler
                 BlockState state = world.getBlockState(blockPos);
                 if (liquidContainer.canPlaceLiquid(world, blockPos, state, resource.getFluid()))
                 {
-                    //If we are executing try to actually fill the container, if it failed return that we failed
-                    if (action.simulate() || liquidContainer.placeLiquid(world, blockPos, state, resource.getFluid().getFluidType().getStateForPlacement(world, blockPos, resource)))
+                    if (action.execute())
                     {
-                        return FluidType.BUCKET_VOLUME;
+                        liquidContainer.placeLiquid(world, blockPos, state, resource.getFluid().getFluidType().getStateForPlacement(world, blockPos, resource));
                     }
+                    return FluidType.BUCKET_VOLUME;
                 }
             }
             return 0;

src/main/java/net/minecraftforge/network/DualStackUtils.java

@@ -5,12 +5,21 @@
 
 package net.minecraftforge.network;
 
+import com.mojang.logging.LogUtils;
+import com.google.common.net.InetAddresses;
 import net.minecraft.client.multiplayer.resolver.ResolvedServerAddress;
 import net.minecraft.client.multiplayer.resolver.ServerAddress;
 import net.minecraft.client.multiplayer.resolver.ServerNameResolver;
 import net.minecraft.util.HttpUtil;
+import org.jetbrains.annotations.ApiStatus;
+import org.slf4j.Logger;
 
 import javax.annotation.Nullable;
+import java.net.Inet4Address;
+import net.minecraftforge.common.ForgeConfig;
+
+import javax.annotation.Nullable;
+import java.net.SocketAddress;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
@@ -19,6 +28,19 @@ import java.util.Optional;
 
 public class DualStackUtils
 {
+    private static final String INITIAL_PREFER_IPv4_STACK = System.getProperty("java.net.preferIPv4Stack") == null ? "false" : System.getProperty("java.net.preferIPv4Stack");
+    private static final String INITIAL_PREFER_IPv6_ADDRESSES = System.getProperty("java.net.preferIPv6Addresses") == null ? "false" : System.getProperty("java.net.preferIPv6Addresses");
+
+    private static final Logger LOGGER = LogUtils.getLogger();
+
+    /**
+     * Called by {@link net.minecraftforge.common.MinecraftForge} to load this class so that the initial network
+     * property constants are set before any of the other methods in this class are called. This is so we can
+     * distinguish what Java's read once on JVM start vs what we've set for Netty.
+     */
+    @ApiStatus.Internal
+    public static void initialise() {}
+
     /**
      * Resolve the address and see if Java and the OS return an IPv6 or IPv4 one, then let Netty know
      * accordingly (it doesn't understand the {@code java.net.preferIPv6Addresses=system} property).
@@ -45,14 +67,49 @@ public class DualStackUtils
      */
     public static boolean checkIPv6(final InetAddress inetAddress)
     {
-        if (inetAddress instanceof Inet6Address)
+        // only log debug messages if we're not in the server pinger thread, as otherwise it's unclear which IP
+        // corresponds to which server as soon as you have more than one server in the multiplayer server list
+        final String currentThreadName = Thread.currentThread().getName();
+        final boolean shouldLogDebug = !currentThreadName.contains("Server Pinger #");
+
+        if (inetAddress instanceof Inet6Address addr)
         {
+            if (shouldLogDebug)
+                LOGGER.debug("Detected IPv6 address: \"" + addr.getHostAddress() + "\"");
+
             System.setProperty("java.net.preferIPv4Stack", "false");
             System.setProperty("java.net.preferIPv6Addresses", "true");
             return true;
         }
+        else if (inetAddress instanceof Inet4Address addr)
+        {
+            if (shouldLogDebug)
+                LOGGER.debug("Detected IPv4 address: \"" + addr.getHostAddress() + "\"");
+
+            System.setProperty("java.net.preferIPv4Stack", "true");
+            System.setProperty("java.net.preferIPv6Addresses", "false");
+            return false;
+        }
         else
         {
+            if (shouldLogDebug) {
+                final String addr = inetAddress == null ? "null" : "\"" + inetAddress.getHostAddress() + "\"";
+                LOGGER.debug("Unable to determine IP version of address: " + addr);
+            }
+
+            if (INITIAL_PREFER_IPv4_STACK.equalsIgnoreCase("false") && INITIAL_PREFER_IPv6_ADDRESSES.equalsIgnoreCase("true"))
+            {
+                if (shouldLogDebug)
+                    LOGGER.debug("Assuming IPv6 as Java was explicitly told to prefer it...");
+
+                System.setProperty("java.net.preferIPv4Stack", "false");
+                System.setProperty("java.net.preferIPv6Addresses", "true");
+                return true;
+            }
+
+            if (shouldLogDebug)
+                LOGGER.debug("Assuming IPv4...");
+
             System.setProperty("java.net.preferIPv4Stack", "true");
             System.setProperty("java.net.preferIPv6Addresses", "false");
             return false;
@@ -81,8 +138,43 @@ public class DualStackUtils
         }
     }
 
+    /**
+     * Used for the "Open to LAN" feature.
+     * @return The multicast group to use for LAN discovery - IPv6 if available, IPv4 otherwise.
+     */
     public static String getMulticastGroup() {
         if (checkIPv6(getLocalAddress())) return "FF75:230::60";
         else return "224.0.2.60";
     }
+
+    /**
+     * Logs the initial values of the {@code java.net.preferIPv4Stack} and {@code java.net.preferIPv6Addresses} system
+     * properties that Java has read on JVM start. Useful for debugging hostname lookup failures.
+     */
+    public static void logInitialPreferences() {
+        LOGGER.debug("Initial IPv4 stack preference: " + INITIAL_PREFER_IPv4_STACK);
+        LOGGER.debug("Initial IPv6 addresses preference: " + INITIAL_PREFER_IPv6_ADDRESSES);
+    }
+
+    /**
+     * {@link SocketAddress#toString()} but with IPv6 address compression support
+     */
+    public static String getAddressString(final SocketAddress address) {
+        if (address instanceof final InetSocketAddress inetAddress) {
+            String formatted;
+            if (inetAddress.isUnresolved()) {
+                formatted = inetAddress.getHostName() + "/<unresolved>";
+            } else {
+                formatted = InetAddresses.toAddrString(inetAddress.getAddress());
+                if (inetAddress.getAddress() instanceof Inet6Address)
+                    formatted = '[' + formatted + ']';
+
+                formatted = '/' + formatted;
+            }
+
+            return formatted + ':' + inetAddress.getPort();
+        }
+
+        return address.toString();
+    }
 }

src/main/java/net/minecraftforge/resource/DelegatingPackResources.java

@@ -103,7 +103,7 @@ public class DelegatingPackResources extends AbstractPackResources
         {
             IoSupplier<InputStream> ioSupplier = pack.getResource(type, location);
             if (ioSupplier != null)
-                return pack.getResource(type, location);
+                return ioSupplier;
         }
 
         return null;

src/main/resources/forge.sas

@@ -4,4 +4,6 @@
 # checkAndFixSAS will populate all overrides as nessasary. Prefixing added lines with \t
 # checkAndFixSAS also supports names using . so simplest way to find the correct line to add is to get the AT line from the bot
 #   and remove the access modifier.
-#==================================================================================================================================
+# You need to run the setup task again after running checkAndFixSAS for genPatches to pick up the changes.
+#==================================================================================================================================
+net/minecraft/client/server/LanServerPinger

src/test/java/net/minecraftforge/debug/AlterGroundEventTest.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.debug;
+
+import net.minecraft.world.level.block.Blocks;
+import net.minecraftforge.event.level.AlterGroundEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
+import net.minecraftforge.fml.common.Mod;
+
+@Mod("alter_ground_event_test")
+@Mod.EventBusSubscriber
+public class AlterGroundEventTest {
+    public static final boolean ENABLE = true;
+
+    @SubscribeEvent
+    public static void onAlterGround(AlterGroundEvent event)
+    {
+        if (ENABLE) {
+            if (event.getOriginalAlteredState().is(Blocks.PODZOL)) {
+                event.setNewAlteredState(Blocks.REDSTONE_BLOCK.defaultBlockState());
+            }
+        }
+    }
+}

src/test/java/net/minecraftforge/debug/DataGeneratorTest.java

@@ -15,6 +15,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -34,6 +35,7 @@ import net.minecraft.DetectedVersion;
 import net.minecraft.Util;
 import net.minecraft.advancements.critereon.InventoryChangeTrigger;
 import net.minecraft.core.*;
+import net.minecraft.core.particles.ParticleTypes;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.data.CachedOutput;
 import net.minecraft.data.PackOutput;
@@ -169,6 +171,7 @@ public class DataGeneratorTest
         gen.addProvider(event.includeClient(), itemModels);
         gen.addProvider(event.includeClient(), new BlockStates(packOutput, itemModels.existingFileHelper));
         gen.addProvider(event.includeClient(), new SoundDefinitions(packOutput, event.getExistingFileHelper()));
+        gen.addProvider(event.includeClient(), new ParticleDescriptions(packOutput, event.getExistingFileHelper()));
 
         gen.addProvider(event.includeServer(), new Recipes(packOutput));
         gen.addProvider(event.includeServer(), new Tags(packOutput, lookupProvider, event.getExistingFileHelper()));
@@ -1120,6 +1123,80 @@ public class DataGeneratorTest
         }
     }
 
+    private static class ParticleDescriptions extends ParticleDescriptionProvider {
+
+        public ParticleDescriptions(PackOutput output, ExistingFileHelper fileHelper) {
+            super(output, fileHelper);
+        }
+
+        @Override
+        protected void addDescriptions() {
+            this.sprite(ParticleTypes.DRIPPING_LAVA, new ResourceLocation("drip_hang"));
+
+            this.spriteSet(ParticleTypes.CLOUD, new ResourceLocation("generic"), 8, true);
+
+            this.spriteSet(ParticleTypes.FISHING,
+                    new ResourceLocation("splash_0"),
+                    new ResourceLocation("splash_1"),
+                    new ResourceLocation("splash_2"),
+                    new ResourceLocation("splash_3")
+            );
+
+            this.spriteSet(ParticleTypes.ENCHANT, () -> new Iterator<>() {
+
+                private final ResourceLocation base = new ResourceLocation("sga");
+                private char suffix = 'a';
+
+                @Override
+                public boolean hasNext() {
+                    return this.suffix <= 'z';
+                }
+
+                @Override
+                public ResourceLocation next() {
+                    return this.base.withSuffix("_" + this.suffix++);
+                }
+            });
+        }
+
+        @Override
+        public CompletableFuture<?> run(CachedOutput cache) {
+            return super.run(cache).thenRun(this::validateResults);
+        }
+
+        private void validateResults() {
+            var errors = Stream.of(ParticleTypes.DRIPPING_LAVA, ParticleTypes.CLOUD, ParticleTypes.FISHING, ParticleTypes.ENCHANT)
+                    .map(ForgeRegistries.PARTICLE_TYPES::getKey).map(particle -> {
+                        try (var resource = this.fileHelper.getResource(particle, PackType.CLIENT_RESOURCES, ".json", "particles").openAsReader()) {
+                            var existingTextures = GSON.fromJson(resource, JsonObject.class).get("textures").getAsJsonArray();
+                            var generatedTextures = this.descriptions.get(particle);
+
+                            // Check texture size
+                            if (existingTextures.size() != generatedTextures.size()) {
+                                LOGGER.error("%s had a different number of sprites, expected %s, actual %s", particle, existingTextures.size(), generatedTextures.size());
+                                return particle;
+                            }
+
+                            boolean error = false;
+                            for (int i = 0; i < generatedTextures.size(); ++i) {
+                                if (!existingTextures.get(i).getAsString().equals(generatedTextures.get(i))) {
+                                    LOGGER.error("%s index %s: expected %s, actual %s", particle, i, existingTextures.get(i).getAsString(), generatedTextures.get(i));
+                                    error = true;
+                                }
+                            }
+
+                            return error ? particle : null;
+                        } catch (IOException e) {
+                            throw new RuntimeException(e);
+                        }
+                    }).filter(Objects::nonNull).toList();
+
+            if (!errors.isEmpty()) {
+                throw new AssertionError(String.format("Validation errors found in %s; see above for details", errors.stream().reduce("", (str, rl) -> str + ", " + rl, (str1, str2) -> str1 + ", " + str2)));
+            }
+        }
+    }
+
     private static <T extends ModelBuilder<T>> List<String> testModelResults(Map<ResourceLocation, T> models, ExistingFileHelper existingFileHelper, Set<ResourceLocation> toIgnore) {
         List<String> ret = new ArrayList<>();
         models.forEach((loc, model) -> {

src/test/java/net/minecraftforge/debug/FluidUtilTest.java

@@ -38,6 +38,7 @@ public class FluidUtilTest
 	private static void runTests(FMLCommonSetupEvent commonSetupEvent)
 	{
 		test_tryEmptyContainer();
+		test_tryFillContainer();
 		test_tryEmptyContainerAndStow_stackable();
 
 		LogManager.getLogger().info("FluidUtilTest ok!");
@@ -70,6 +71,35 @@ public class FluidUtilTest
 		checkItemStack(sourceStack, Items.WATER_BUCKET, 2); // Apparently the stack is not supposed to be modified
 	}
 
+	/**
+	 * Ensures that tryFillContainer doesn't change the target fluid handler when simulating.
+	 * Ant that the result of the simulated transfver is valid.
+	 * Regression test for the root cause of <a href="https://github.com/MinecraftForge/MinecraftForge/issues/6796">issue #6796</a>.
+	 */
+	private static void test_tryFillContainer()
+	{
+		var targetStack = new ItemStack(Items.BUCKET, 2);
+		var sourceTank = new FluidTank(10000);
+		sourceTank.setFluid(new FluidStack(Fluids.WATER, 5000));
+
+		// Simulate is not supposed to modify anything
+		var simulateResult = FluidUtil.tryFillContainer(targetStack, sourceTank, 1000, null, false);
+		if (!simulateResult.isSuccess())
+			throw new AssertionError("Failed to transfer.");
+		checkItemStack(simulateResult.getResult(), Items.WATER_BUCKET, 1);
+		// Tank and stack shouldn't be modified
+		checkItemStack(targetStack, Items.BUCKET, 2);
+		checkFluidStack(sourceTank.getFluid(), Fluids.WATER, 5000);
+
+		// Execute should modify
+		var executeResult = FluidUtil.tryFillContainer(targetStack, sourceTank, 1000, null, true);
+		if (!executeResult.isSuccess())
+			throw new AssertionError("Failed to transfer.");
+		checkItemStack(executeResult.getResult(), Items.WATER_BUCKET, 1);
+		checkFluidStack(sourceTank.getFluid(), Fluids.WATER, 4000);
+		checkItemStack(targetStack, Items.BUCKET, 2);
+	}
+
 	/**
 	 * Ensures that tryEmptyContainerAndStow doesn't duplicate fluids in the target when the container is stackable.
 	 * Regression test for <a href="https://github.com/MinecraftForge/MinecraftForge/issues/6796">issue #6796</a>.

src/test/java/net/minecraftforge/debug/KeyMappingTest.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.debug;
+
+import com.mojang.blaze3d.platform.InputConstants;
+import net.minecraft.client.KeyMapping;
+import net.minecraft.client.Minecraft;
+import net.minecraft.network.chat.Component;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.Items;
+import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.client.event.RegisterKeyMappingsEvent;
+import net.minecraftforge.common.MinecraftForge;
+import net.minecraftforge.event.TickEvent;
+import net.minecraftforge.eventbus.api.SubscribeEvent;
+import net.minecraftforge.fml.common.Mod;
+import net.minecraftforge.fml.event.lifecycle.FMLConstructModEvent;
+
+@Mod("keymapping_test")
+public class KeyMappingTest
+{
+    @Mod.EventBusSubscriber(modid = "keymapping_test", value = Dist.CLIENT, bus = Mod.EventBusSubscriber.Bus.MOD)
+    public static class ClientStuff {
+        // these are two separate keys to stand in for keys added by different
+        // mods that each do something similar with a held item from the
+        // respective mod, so the user wants them on the same physical key.
+        static KeyMapping stickKey = new KeyMapping("stick_key", InputConstants.KEY_BACKSLASH, KeyMapping.CATEGORY_MISC);
+        static KeyMapping rockKey = new KeyMapping("rock_key", InputConstants.KEY_BACKSLASH, KeyMapping.CATEGORY_MISC);
+        @SubscribeEvent
+        public static void init(FMLConstructModEvent event) {
+            MinecraftForge.EVENT_BUS.addListener(ClientStuff::tick);
+        }
+        @SubscribeEvent
+        public static void initKeys(RegisterKeyMappingsEvent event) {
+            event.register(stickKey);
+            event.register(rockKey);
+        }
+        public static void tick(TickEvent.ClientTickEvent event) {
+            if(event.phase != TickEvent.Phase.START) return;
+            if(stickKey.consumeClick()) {
+                Player player = Minecraft.getInstance().player;
+                if(player != null && player.getMainHandItem().is(Items.STICK))
+                    player.sendSystemMessage(Component.literal("stick found!"));
+            }
+            if(rockKey.consumeClick()) {
+                Player player = Minecraft.getInstance().player;
+                if(player != null && player.getMainHandItem().is(Items.COBBLESTONE))
+                    player.sendSystemMessage(Component.literal("rock found!"));
+            }
+        }
+    }
+}

src/test/java/net/minecraftforge/debug/item/CustomFluidContainerTest.java

@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) Forge Development LLC and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.debug.item;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.network.chat.Component;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.InteractionResultHolder;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.item.CreativeModeTabs;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.ClipContext;
+import net.minecraft.world.level.Level;
+import net.minecraftforge.common.capabilities.ICapabilityProvider;
+import net.minecraftforge.event.CreativeModeTabEvent;
+import net.minecraftforge.eventbus.api.IEventBus;
+import net.minecraftforge.fluids.FluidActionResult;
+import net.minecraftforge.fluids.FluidStack;
+import net.minecraftforge.fluids.FluidType;
+import net.minecraftforge.fluids.FluidUtil;
+import net.minecraftforge.fluids.capability.templates.FluidHandlerItemStackSimple;
+import net.minecraftforge.fml.common.Mod;
+import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
+import net.minecraftforge.registries.DeferredRegister;
+import net.minecraftforge.registries.ForgeRegistries;
+import net.minecraftforge.registries.RegistryObject;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.Arrays;
+import java.util.concurrent.atomic.AtomicReference;
+
+@Mod(CustomFluidContainerTest.MODID)
+public class CustomFluidContainerTest
+{
+    public static final String MODID = "custom_fluid_container_test";
+    public static final DeferredRegister<Item> ITEMS = DeferredRegister.create(ForgeRegistries.ITEMS, MODID);
+
+    public static final boolean ENABLED = true;
+
+    public static final RegistryObject<Item> CUSTOM_FLUID_CONTAINER = ITEMS.register("custom_fluid_container", () -> new CustomFluidContainer((new Item.Properties()).stacksTo(1)));
+
+    public CustomFluidContainerTest()
+    {
+        if (ENABLED)
+        {
+            IEventBus modEventBus = FMLJavaModLoadingContext.get().getModEventBus();
+            ITEMS.register(modEventBus);
+            modEventBus.addListener(this::addCreative);
+        }
+    }
+
+    private void addCreative(CreativeModeTabEvent.BuildContents event)
+    {
+        if (event.getTab() == CreativeModeTabs.INGREDIENTS)
+            event.accept(CUSTOM_FLUID_CONTAINER);
+    }
+
+    /**
+     * A custom fluid container item with a capacity of a vanilla bucket which uses the FluidUtil functionalities to pickup and place fluids.
+     */
+    private static class CustomFluidContainer extends Item
+    {
+
+        public CustomFluidContainer(Properties properties)
+        {
+            super(properties);
+        }
+
+        @Override
+        @Nonnull
+        public Component getName(@Nonnull ItemStack itemStack) {
+            AtomicReference<String> name = new AtomicReference<>("Custom Fluid Container");
+            FluidUtil.getFluidHandler(itemStack).ifPresent(fluidHandler ->
+            {
+                FluidStack fluidStack = fluidHandler.getFluidInTank(0);
+                if (fluidStack.isEmpty())
+                {
+                    name.set(name.get() + " (empty)");
+                }
+                else
+                {
+                    name.set(name.get() + " (" + fluidStack.getFluid().getFluidType().getDescription().getString() + ")");
+                }
+            });
+            return Component.literal(name.get());
+        }
+
+        @Override
+        public InteractionResultHolder<ItemStack> use(Level level, Player player, InteractionHand hand)
+        {
+            var itemStack = player.getItemInHand(hand);
+            var result = new AtomicReference<FluidActionResult>();
+            FluidUtil.getFluidHandler(itemStack).ifPresent(fluidHandler ->
+            {
+                var fluidStack = fluidHandler.getFluidInTank(0);
+                if (fluidStack.isEmpty())
+                {
+                    var blockHitResult = getPlayerPOVHitResult(level, player, ClipContext.Fluid.SOURCE_ONLY);
+                    result.set(FluidUtil.tryPickUpFluid(itemStack, player, level, blockHitResult.getBlockPos(), blockHitResult.getDirection()));
+                }
+                else
+                {
+                    var blockHitResult = getPlayerPOVHitResult(level, player, ClipContext.Fluid.NONE);
+                    //try to place fluid in hit block (waterlogging, fill tank, ...). When no success try the block on the hit side.
+                    for (BlockPos pos : Arrays.asList(blockHitResult.getBlockPos(), blockHitResult.getBlockPos().relative(blockHitResult.getDirection())))
+                    {
+                        result.set(FluidUtil.tryPlaceFluid(player, level, hand, pos, itemStack, fluidStack));
+                        if (result.get().isSuccess())
+                        {
+                            break;
+                        }
+                    }
+                }
+            });
+            if (result.get() != null && result.get().isSuccess())
+            {
+                return InteractionResultHolder.sidedSuccess(result.get().getResult(), level.isClientSide());
+            }
+            return super.use(level, player, hand);
+        }
+
+        @Override
+        public ICapabilityProvider initCapabilities(@Nonnull ItemStack stack, @Nullable CompoundTag nbt)
+        {
+            return new FluidHandlerItemStackSimple(stack, FluidType.BUCKET_VOLUME);
+        }
+
+    }
+}

src/test/resources/META-INF/mods.toml

@@ -293,6 +293,12 @@ modId="render_level_stages_test"
 modId="trade_with_villager_event_test"
 [[mods]]
 modId="chunk_event_load_new_chunk_test"
+[[mods]]
+modId="alter_ground_event_test"
+[[mods]]
+modId="custom_fluid_container_test"
+[[mods]]
+    modId="keymapping_test"
 
 
 # ADD ABOVE THIS LINE

src/test/resources/assets/custom_fluid_container_test/models/item/custom_fluid_container.json

@@ -0,0 +1,6 @@
+{
+  "parent": "item/generated",
+  "textures": {
+    "layer0": "item/bucket"
+  }
+}