Allow UPDATE mixin to soft-fail on Fabric (#1654)

This allows Carpet's mixin to take priorty, and UPDATE will simply be
disabled on Fabric in that case. Fixes #1605

worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/FabricPlatform.java

@@ -19,6 +19,7 @@
 
 package com.sk89q.worldedit.fabric;
 
+import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
 import com.mojang.brigadier.CommandDispatcher;
 import com.sk89q.worldedit.command.util.PermissionCondition;
@@ -29,6 +30,7 @@
 import com.sk89q.worldedit.extension.platform.MultiUserPlatform;
 import com.sk89q.worldedit.extension.platform.Preference;
 import com.sk89q.worldedit.extension.platform.Watchdog;
+import com.sk89q.worldedit.fabric.internal.ExtendedChunk;
 import com.sk89q.worldedit.util.SideEffect;
 import com.sk89q.worldedit.world.DataFixer;
 import com.sk89q.worldedit.world.World;
@@ -42,6 +44,7 @@
 import net.minecraft.server.world.ServerWorld;
 import net.minecraft.util.Identifier;
 import net.minecraft.util.registry.Registry;
+import net.minecraft.world.chunk.WorldChunk;
 import net.minecraft.world.level.ServerWorldProperties;
 import org.enginehub.piston.Command;
 import org.enginehub.piston.CommandManager;
@@ -212,17 +215,22 @@ public Map<Capability, Preference> getCapabilities() {
         return capabilities;
     }
 
+    private static final Set<SideEffect> SUPPORTED_SIDE_EFFECTS_NO_MIXIN = Sets.immutableEnumSet(
+        SideEffect.VALIDATION,
+        SideEffect.ENTITY_AI,
+        SideEffect.LIGHTING,
+        SideEffect.NEIGHBORS
+    );
+
     private static final Set<SideEffect> SUPPORTED_SIDE_EFFECTS = Sets.immutableEnumSet(
-            SideEffect.VALIDATION,
+        Iterables.concat(SUPPORTED_SIDE_EFFECTS_NO_MIXIN, Collections.singleton(SideEffect.UPDATE))
-            SideEffect.ENTITY_AI,
-            SideEffect.LIGHTING,
-            SideEffect.NEIGHBORS,
-            SideEffect.UPDATE
     );
 
     @Override
     public Set<SideEffect> getSupportedSideEffects() {
-        return SUPPORTED_SIDE_EFFECTS;
+        return ExtendedChunk.class.isAssignableFrom(WorldChunk.class)
+            ? SUPPORTED_SIDE_EFFECTS
+            : SUPPORTED_SIDE_EFFECTS_NO_MIXIN;
     }
 
     @Override

worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/internal/MixinConfigPlugin.java

@@ -0,0 +1,73 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.fabric.internal;
+
+import net.fabricmc.loader.api.FabricLoader;
+import org.objectweb.asm.tree.ClassNode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.spongepowered.asm.mixin.Mixins;
+import org.spongepowered.asm.mixin.extensibility.IMixinConfigPlugin;
+import org.spongepowered.asm.mixin.extensibility.IMixinInfo;
+
+import java.util.List;
+import java.util.Set;
+
+public class MixinConfigPlugin implements IMixinConfigPlugin {
+    private static final Logger LOGGER = LoggerFactory.getLogger(MixinConfigPlugin.class);
+
+    @Override
+    public void onLoad(String mixinPackage) {
+    }
+
+    @Override
+    public String getRefMapperConfig() {
+        return null;
+    }
+
+    @Override
+    public boolean shouldApplyMixin(String targetClassName, String mixinClassName) {
+        if (mixinClassName.equals("com.sk89q.worldedit.fabric.mixin.MixinWorldChunkSetBlockHook")) {
+            boolean carpet = FabricLoader.getInstance().getModContainer("carpet").isPresent();
+            if (carpet) {
+                LOGGER.warn("Carpet detected, disabling UPDATE mixin " + mixinClassName);
+            }
+            return !carpet;
+        }
+        return true;
+    }
+
+    @Override
+    public void acceptTargets(Set<String> myTargets, Set<String> otherTargets) {
+    }
+
+    @Override
+    public List<String> getMixins() {
+        return null;
+    }
+
+    @Override
+    public void preApply(String targetClassName, ClassNode targetClass, String mixinClassName, IMixinInfo mixinInfo) {
+    }
+
+    @Override
+    public void postApply(String targetClassName, ClassNode targetClass, String mixinClassName, IMixinInfo mixinInfo) {
+    }
+}

worldedit-fabric/src/main/java/com/sk89q/worldedit/fabric/mixin/MixinWorldChunkSetBlockHook.java

@@ -26,6 +26,7 @@
 import net.minecraft.world.World;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.WorldChunk;
+import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Redirect;
@@ -33,8 +34,8 @@
 
 import javax.annotation.Nullable;
 
-@Mixin(WorldChunk.class)
+@Mixin(value = WorldChunk.class)
-public abstract class MixinWorldChunk implements Chunk, ExtendedChunk {
+public abstract class MixinWorldChunkSetBlockHook implements Chunk, ExtendedChunk {
     private boolean shouldUpdate = true;
 
     @Nullable

worldedit-fabric/src/main/resources/worldedit.mixins.json

@@ -6,11 +6,12 @@
         "MixinBiomeArray",
         "MixinServerPlayerEntity",
         "MixinMinecraftServer",
-        "MixinWorldChunk",
+        "MixinWorldChunkSetBlockHook",
         "AccessorClientSettingsC2SPacket",
         "AccessorLevelProperties",
         "AccessorServerChunkManager"
     ],
+    "plugin": "com.sk89q.worldedit.fabric.internal.MixinConfigPlugin",
     "server": [
     ],
     "injectors": {