Merge branch '0.11.0-interf' into dev/0.11.0

# Conflicts:
#	.github/workflows/test.yml
#	build.gradle
#	src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java
#	src/main/java/net/fabricmc/loom/build/JarRemapper.java
#	src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java
#	src/main/java/net/fabricmc/loom/build/ModCompileRemapper.java
#	src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java
#	src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java
#	src/main/java/net/fabricmc/loom/configuration/JarManifestConfiguration.java
#	src/main/java/net/fabricmc/loom/configuration/RemapConfiguration.java
#	src/main/java/net/fabricmc/loom/configuration/ide/RunConfig.java
#	src/main/java/net/fabricmc/loom/configuration/ide/SetupIntelijRunConfigs.java
#	src/main/java/net/fabricmc/loom/configuration/providers/LaunchProvider.java
#	src/main/java/net/fabricmc/loom/configuration/providers/MinecraftProviderImpl.java
#	src/main/java/net/fabricmc/loom/configuration/providers/minecraft/MinecraftMappedProvider.java
#	src/main/java/net/fabricmc/loom/extension/MixinExtensionImpl.java
#	src/main/java/net/fabricmc/loom/task/LoomTasks.java
#	src/main/java/net/fabricmc/loom/task/RemapJarTask.java
#	src/main/java/net/fabricmc/loom/task/RemapSourcesJarTask.java
#	src/main/java/net/fabricmc/loom/util/Constants.java
#	src/test/groovy/net/fabricmc/loom/test/unit/layeredmappings/LayeredMappingSpecBuilderTest.groovy

.github/workflows/test.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - uses: gradle/wrapper-validation-action@v1
-      - run: gradle build check -x test --stacktrace
+      - run: gradle build check -x test --stacktrace --warning-mode fail
 
   # This job is used to feed the test matrix of next job to allow the tests to run in parallel
   prepare_test_matrix:
@@ -27,7 +27,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
-      - run: gradle writeActionsTestMatrix --stacktrace
+      - run: gradle writeActionsTestMatrix --stacktrace --warning-mode fail
       - id: set-matrix
         run: echo "::set-output name=matrix::$(cat build/test_matrix.json)"
 
@@ -50,7 +50,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
-      - run: gradle test --tests ${{ matrix.test }} --stacktrace
+      - run: gradle test --tests ${{ matrix.test }} --stacktrace --warning-mode fail
         env:
           TEST_WARNING_MODE: fail
 
@@ -77,7 +77,7 @@ jobs:
         uses: actions/setup-java@v1
         with:
           java-version: ${{ matrix.java }}
-      - run: ./gradlew test --tests ${{ matrix.test }} --stacktrace
+      - run: ./gradlew test --tests ${{ matrix.test }} --stacktrace --warning-mode fail
         env:
           TEST_WARNING_MODE: fail
 

build.gradle

@@ -207,8 +207,8 @@ jacoco {
 jacocoTestReport {
 	dependsOn test
 	reports {
-		xml.enabled false
-		csv.enabled false
+		xml.required = false
+		csv.required = false
 		html.destination file("${buildDir}/jacocoHtml")
 	}
 }
@@ -220,6 +220,7 @@ test {
 }
 
 import me.shedaniel.javaversionbridge.BridgeTransformingTask
+import org.gradle.util.GradleVersion
 import org.w3c.dom.Document
 import org.w3c.dom.Element
 import org.w3c.dom.Node
@@ -338,6 +339,27 @@ tasks.named('wrapper') {
 	distributionType = Wrapper.DistributionType.ALL
 }
 
+/**
+ * Run this task to download the gradle sources next to the api jar, you may need to manually attach the sources jar
+ */
+task downloadGradleSources() {
+	doLast {
+		// Awful hack to find the gradle api location
+		def gradleApiFile = project.configurations.detachedConfiguration(dependencies.gradleApi()).files.stream()
+			.filter {
+				it.name.startsWith("gradle-api")
+			}.findFirst().orElseThrow()
+
+		def gradleApiSources = new File(gradleApiFile.absolutePath.replace(".jar", "-sources.jar"))
+		def url = "https://services.gradle.org/distributions/gradle-${GradleVersion.current().getVersion()}-src.zip"
+
+		gradleApiSources.delete()
+
+		println("Downloading (${url}) to (${gradleApiSources})")
+		gradleApiSources << new URL(url).newInputStream()
+	}
+}
+
 tasks.withType(GenerateModuleMetadata) {
 	enabled = false
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.2-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

src/main/java/net/fabricmc/loom/LoomGradleExtension.java

@@ -26,15 +26,17 @@ package net.fabricmc.loom;
 
 import java.io.File;
 import java.util.List;
-import java.util.Set;
 import java.util.function.Supplier;
 
 import org.cadixdev.lorenz.MappingSet;
 import org.cadixdev.mercury.Mercury;
+import org.gradle.api.Action;
 import org.gradle.api.NamedDomainObjectProvider;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.file.FileCollection;
+import org.gradle.api.tasks.SourceSet;
 
 import net.fabricmc.loom.api.LoomGradleExtensionAPI;
 import net.fabricmc.loom.configuration.InstallerData;
@@ -61,7 +63,12 @@ public interface LoomGradleExtension extends LoomGradleExtensionAPI {
 
 	LoomFiles getFiles();
 
-	NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name);
+	default NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name) {
+		return createLazyConfiguration(name, config -> {
+		});
+	}
+
+	NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name, Action<? super Configuration> configurationAction);
 
 	NamedDomainObjectProvider<Configuration> getLazyConfigurationProvider(String name);
 
@@ -95,16 +102,12 @@ public interface LoomGradleExtension extends LoomGradleExtensionAPI {
 		return getMappingsProvider().mappedProvider;
 	}
 
-	File getNextMixinMappings();
+	File getMixinMappings(SourceSet sourceSet);
 
-	Set<File> getAllMixinMappings();
+	FileCollection getAllMixinMappings();
 
 	boolean isRootProject();
 
-	default boolean ideSync() {
-		return Boolean.parseBoolean(System.getProperty("idea.sync.active", "false"));
-	}
-
 	default String getIntermediaryUrl(String minecraftVersion) {
 		return String.format(this.getIntermediaryUrl().get(), minecraftVersion);
 	}

src/main/java/net/fabricmc/loom/LoomGradlePlugin.java

@@ -43,6 +43,7 @@ import net.fabricmc.loom.configuration.CompileConfiguration;
 import net.fabricmc.loom.configuration.FabricApiExtension;
 import net.fabricmc.loom.configuration.MavenPublication;
 import net.fabricmc.loom.configuration.ide.IdeConfiguration;
+import net.fabricmc.loom.configuration.ide.idea.IdeaConfiguration;
 import net.fabricmc.loom.decompilers.DecompilerConfiguration;
 import net.fabricmc.loom.extension.LoomFiles;
 import net.fabricmc.loom.extension.LoomGradleExtensionImpl;
@@ -93,5 +94,6 @@ public class LoomGradlePlugin implements BootstrappedPlugin {
 		MavenPublication.configure(project);
 		LoomTasks.registerTasks(project);
 		DecompilerConfiguration.setup(project);
+		IdeaConfiguration.setup(project);
 	}
 }

src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java

@@ -28,6 +28,7 @@ import java.util.List;
 import java.util.function.Consumer;
 
 import org.gradle.api.Action;
+import org.gradle.api.DomainObjectCollection;
 import org.gradle.api.NamedDomainObjectContainer;
 import org.gradle.api.artifacts.Dependency;
 import org.gradle.api.file.ConfigurableFileCollection;
@@ -63,7 +64,7 @@ public interface LoomGradleExtensionAPI {
 		getShareRemapCaches().set(true);
 	}
 
-	ListProperty<LoomDecompiler> getGameDecompilers();
+	DomainObjectCollection<LoomDecompiler> getGameDecompilers();
 
 	default void addDecompiler(LoomDecompiler decompiler) {
 		getGameDecompilers().add(decompiler);
@@ -140,6 +141,15 @@ public interface LoomGradleExtensionAPI {
 	 */
 	Property<String> getIntermediaryUrl();
 
+	/**
+	 * When true loom will inject interfaces declared in mod manifests into the minecraft jar file.
+	 * This is used to expose interfaces that are implemented on Minecraft classes by mixins at runtime
+	 * in the dev environment.
+	 *
+	 * @return the property controlling interface injection.
+	 */
+	Property<Boolean> getEnableInterfaceInjection();
+
 	// ===================
 	//  Architectury Loom
 	// ===================

src/main/java/net/fabricmc/loom/api/decompilers/LoomDecompiler.java

@@ -26,6 +26,10 @@ package net.fabricmc.loom.api.decompilers;
 
 import java.nio.file.Path;
 
+import org.gradle.api.Project;
+import org.gradle.api.file.FileCollection;
+import org.jetbrains.annotations.Nullable;
+
 public interface LoomDecompiler {
 	String name();
 
@@ -37,4 +41,12 @@ public interface LoomDecompiler {
 	 * @param metaData Additional information that may or may not be needed while decompiling
 	 */
 	void decompile(Path compiledJar, Path sourcesDestination, Path linemapDestination, DecompilationMetadata metaData);
+
+	/**
+	 * Add additional classpath entries to the decompiler classpath, can return a configuration.
+	 */
+	@Nullable
+	default FileCollection getBootstrapClasspath(Project project) {
+		return null;
+	}
 }

src/main/java/net/fabricmc/loom/api/mappings/layered/spec/LayeredMappingSpecBuilder.java

@@ -27,9 +27,10 @@ package net.fabricmc.loom.api.mappings.layered.spec;
 import groovy.lang.Closure;
 import groovy.lang.DelegatesTo;
 import org.gradle.api.Action;
-import org.gradle.util.ConfigureUtil;
 import org.jetbrains.annotations.ApiStatus;
 
+import net.fabricmc.loom.util.ClosureAction;
+
 /**
  * Used to configure a layered mapping spec.
  */
@@ -52,7 +53,7 @@ public interface LayeredMappingSpecBuilder {
 	 */
 	@SuppressWarnings("rawtypes")
 	default LayeredMappingSpecBuilder officialMojangMappings(@DelegatesTo(value = MojangMappingsSpecBuilder.class, strategy = Closure.DELEGATE_FIRST) Closure closure) {
-		return officialMojangMappings(mojangMappingsSpecBuilder -> ConfigureUtil.configure(closure, mojangMappingsSpecBuilder));
+		return officialMojangMappings(new ClosureAction<>(closure));
 	}
 
 	/**
@@ -66,7 +67,7 @@ public interface LayeredMappingSpecBuilder {
 
 	@SuppressWarnings("rawtypes")
 	default LayeredMappingSpecBuilder parchment(Object object, @DelegatesTo(value = ParchmentMappingsSpecBuilder.class, strategy = Closure.DELEGATE_FIRST) Closure closure) {
-		return parchment(object, parchmentMappingsSpecBuilder -> ConfigureUtil.configure(closure, parchmentMappingsSpecBuilder));
+		return parchment(object, new ClosureAction<>(closure));
 	}
 
 	LayeredMappingSpecBuilder parchment(Object object, Action<ParchmentMappingsSpecBuilder> action);

src/main/java/net/fabricmc/loom/build/JarRemapper.java

@@ -1,179 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2020 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.build;
-
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.function.BiConsumer;
-import java.util.function.BiFunction;
-
-import dev.architectury.tinyremapper.IMappingProvider;
-import dev.architectury.tinyremapper.InputTag;
-import dev.architectury.tinyremapper.OutputConsumerPath;
-import dev.architectury.tinyremapper.TinyRemapper;
-import org.gradle.api.Action;
-import org.gradle.api.Project;
-import org.objectweb.asm.commons.Remapper;
-
-import net.fabricmc.loom.util.CloseableList;
-import net.fabricmc.loom.util.LoggerFilter;
-import net.fabricmc.stitch.util.Pair;
-
-public class JarRemapper {
-	private final List<IMappingProvider> mappingProviders = new ArrayList<>();
-	private final Set<Path> classPath = new HashSet<>();
-	private final List<RemapData> remapData = new ArrayList<>();
-	private List<Action<TinyRemapper.Builder>> remapOptions;
-
-	public void addMappings(IMappingProvider mappingProvider) {
-		mappingProviders.add(mappingProvider);
-	}
-
-	public void addToClasspath(Path... paths) {
-		classPath.addAll(Arrays.asList(paths));
-	}
-
-	public RemapData scheduleRemap(Path input, Path output) {
-		RemapData data = new RemapData(input, output);
-		remapData.add(data);
-		return data;
-	}
-
-	public void remap(Project project) throws IOException {
-		LoggerFilter.replaceSystemOut();
-		TinyRemapper.Builder remapperBuilder = TinyRemapper.newRemapper();
-		remapperBuilder.logger(project.getLogger()::lifecycle);
-		remapperBuilder.logUnknownInvokeDynamic(false);
-		mappingProviders.forEach(remapperBuilder::withMappings);
-
-		if (remapOptions != null) {
-			for (Action<TinyRemapper.Builder> remapOption : remapOptions) {
-				remapOption.execute(remapperBuilder);
-			}
-		}
-
-		TinyRemapper remapper = remapperBuilder.build();
-
-		Path[] remapClasspath = classPath.stream()
-				.filter(path ->
-						remapData.stream().noneMatch(remapData -> remapData.input.toString().equals(path.toString()))
-				)
-				.toArray(Path[]::new);
-
-		remapper.readClassPathAsync(remapClasspath);
-
-		for (RemapData data : remapData) {
-			InputTag tag = remapper.createInputTag();
-			data.tag = tag;
-			project.getLogger().info(":remapper input -> " + data.input.getFileName().toString());
-
-			try {
-				remapper.readInputsAsync(tag, data.input);
-			} catch (Exception e) {
-				throw new RuntimeException("Failed to read remapper input " + data.input.getFileName().toString(), e);
-			}
-		}
-
-		//noinspection MismatchedQueryAndUpdateOfCollection
-		try (CloseableList<OutputConsumerPath> outputConsumers = new CloseableList<>()) {
-			for (RemapData data : remapData) {
-				OutputConsumerPath outputConsumer;
-				project.getLogger().info(":remapper output -> " + data.output.getFileName().toString());
-
-				try {
-					Files.deleteIfExists(data.output);
-					outputConsumer = new OutputConsumerPath.Builder(data.output).build();
-				} catch (Exception e) {
-					throw new RuntimeException("Failed to create remapper output " + data.output.getFileName().toString(), e);
-				}
-
-				outputConsumers.add(outputConsumer);
-
-				outputConsumer.addNonClassFiles(data.input);
-
-				data.processAccessWidener(remapper.getRemapper());
-				remapper.apply(outputConsumer, data.tag);
-			}
-
-			remapper.finish();
-		} catch (Exception e) {
-			for (RemapData data : remapData) {
-				// Cleanup bad outputs
-				Files.deleteIfExists(data.output);
-			}
-
-			throw new IOException("Failed to remap %s files".formatted(remapData.size()), e);
-		}
-
-		remapData.forEach(RemapData::complete);
-	}
-
-	public void addOptions(List<Action<TinyRemapper.Builder>> remapOptions) {
-		this.remapOptions = remapOptions;
-	}
-
-	public static class RemapData {
-		public final Path input;
-		public final Path output;
-		BiFunction<RemapData, Remapper, Pair<String, byte[]>> accesWidenerSupplier;
-		BiConsumer<RemapData, Pair<String, byte[]>> onComplete;
-
-		private InputTag tag;
-		private Pair<String, byte[]> accessWidener;
-
-		public RemapData(Path input, Path output) {
-			this.input = input;
-			this.output = output;
-		}
-
-		public RemapData complete(BiConsumer<RemapData, Pair<String, byte[]>> onComplete) {
-			this.onComplete = onComplete;
-			return this;
-		}
-
-		public RemapData supplyAccessWidener(BiFunction<RemapData, Remapper, Pair<String, byte[]>> beforeFinish) {
-			this.accesWidenerSupplier = beforeFinish;
-			return this;
-		}
-
-		private void complete() {
-			if (onComplete != null) {
-				onComplete.accept(this, accessWidener);
-			}
-		}
-
-		private void processAccessWidener(Remapper remapper) {
-			if (accesWidenerSupplier != null) {
-				accessWidener = accesWidenerSupplier.apply(this, remapper);
-			}
-		}
-	}
-}

src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java

@@ -27,13 +27,9 @@ package net.fabricmc.loom.build;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStreamReader;
-import java.io.UncheckedIOException;
-import java.nio.file.Path;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.Objects;
 import java.util.stream.Collectors;
-import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
@@ -41,74 +37,35 @@ import java.util.zip.ZipFile;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
-import org.gradle.api.Project;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
-import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.LoomGradlePlugin;
-import net.fabricmc.loom.extension.MixinExtension;
-import net.fabricmc.loom.util.Pair;
-import net.fabricmc.loom.util.ZipUtils;
 
 public final class MixinRefmapHelper {
 	private MixinRefmapHelper() { }
 
 	private static final String FABRIC_MOD_JSON = "fabric.mod.json";
 
-	public static boolean addRefmapName(Project project, Path outputPath) {
-		try {
-			MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
-			File output = outputPath.toFile();
-
-			Collection<String> allMixinConfigs = LoomGradleExtension.get(project).isForge() ? LoomGradleExtension.get(project).getForge().getMixinConfigs().get() : getMixinConfigurationFiles(readFabricModJson(output));
-
-			return mixin.getMixinSourceSetsStream().map(sourceSet -> {
-				MixinExtension.MixinInformationContainer container = Objects.requireNonNull(
-						MixinExtension.getMixinInformationContainer(sourceSet)
-				);
-
-				Stream<String> mixinConfigs = sourceSet.getResources()
-						.matching(container.mixinConfigPattern())
-						.getFiles()
-						.stream()
-						.map(File::getName)
-						.filter(allMixinConfigs::contains);
-
-				String refmapName = container.refmapNameProvider().get();
-
-				try {
-					return ZipUtils.transformJson(JsonObject.class, outputPath, mixinConfigs.map(f -> new Pair<>(f, json -> {
-						if (!json.has("refmap")) {
-							json.addProperty("refmap", refmapName);
-						}
-
-						return json;
-					}))) > 0;
-				} catch (IOException e) {
-					throw new UncheckedIOException("Failed to transform mixin configs in jar", e);
-				}
-			}).reduce(false, Boolean::logicalOr);
-		} catch (Exception e) {
-			project.getLogger().error(e.getMessage());
-			return false;
-		}
-	}
-
-	@NotNull
-	private static JsonObject readFabricModJson(File output) {
+	@Nullable
+	public static JsonObject readFabricModJson(File output) {
 		try (ZipFile zip = new ZipFile(output)) {
 			ZipEntry entry = zip.getEntry(FABRIC_MOD_JSON);
 
+			if (entry == null) {
+				return null;
+			}
+
 			try (InputStreamReader reader = new InputStreamReader(zip.getInputStream(entry))) {
 				return LoomGradlePlugin.GSON.fromJson(reader, JsonObject.class);
 			}
 		} catch (IOException e) {
-			throw new RuntimeException("Cannot read file fabric.mod.json in the output jar.", e);
+			throw new RuntimeException("Cannot read file fabric.mod.json in the jar.", e);
 		}
 	}
 
 	@NotNull
-	private static Collection<String> getMixinConfigurationFiles(JsonObject fabricModJson) {
+	public static Collection<String> getMixinConfigurationFiles(JsonObject fabricModJson) {
 		JsonArray mixins = fabricModJson.getAsJsonArray("mixins");
 
 		if (mixins == null) {

src/main/java/net/fabricmc/loom/build/ModCompileRemapper.java

@@ -29,7 +29,6 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Supplier;
-import java.util.zip.ZipFile;
 
 import com.google.common.base.Suppliers;
 import com.google.common.io.Files;
@@ -59,6 +58,7 @@ import net.fabricmc.loom.configuration.processors.dependency.ModDependencyInfo;
 import net.fabricmc.loom.configuration.processors.dependency.RemapData;
 import net.fabricmc.loom.util.Checksum;
 import net.fabricmc.loom.util.Constants;
+import net.fabricmc.loom.util.ModUtils;
 import net.fabricmc.loom.util.OperatingSystem;
 import net.fabricmc.loom.util.SourceRemapper;
 
@@ -94,7 +94,7 @@ public class ModCompileRemapper {
 					String name = extension.isForgeAndOfficial() ? "B" + checksum.get() : artifact.getModuleVersion().getId().getName();
 					String version = extension.isForgeAndOfficial() ? "B" + checksum.get() : replaceIfNullOrEmpty(artifact.getModuleVersion().getId().getVersion(), () -> Checksum.truncatedSha256(artifact.getFile()));
 
-					if (!shouldRemapMod(logger, artifact.getFile(), artifact.getId(), extension.isForge(), sourceConfig.getName())) {
+					if (!ModUtils.shouldRemapMod(artifact.getFile(), artifact.getId(), extension.isForge(), sourceConfig.getName())) {
 						addToRegularCompile(project, regularConfig, artifact);
 						continue;
 					}
@@ -121,7 +121,7 @@ public class ModCompileRemapper {
 
 					// Create a mod dependency for each file in the file collection
 					for (File artifact : files) {
-						if (!shouldRemapMod(logger, artifact, artifact.getName(), extension.isForge(), sourceConfig.getName())) {
+						if (!ModUtils.shouldRemapMod(artifact, artifact.getName(), extension.isForge(), sourceConfig.getName())) {
 							dependencies.add(regularConfig.getName(), project.files(artifact));
 							continue;
 						}
@@ -165,37 +165,6 @@ public class ModCompileRemapper {
 		}
 	}
 
-	/**
-	 * Checks if an artifact is a fabric mod, according to the presence of a fabric.mod.json.
-	 */
-	private static boolean shouldRemapMod(Logger logger, File artifact, Object id, boolean forge, String config) {
-		try (ZipFile zipFile = new ZipFile(artifact)) {
-			if (zipFile.getEntry("architectury.common.marker") != null) {
-				logger.info("Found architectury common mod in " + config + ": {}", id);
-				return true;
-			}
-
-			if (forge) {
-				if (zipFile.getEntry("META-INF/mods.toml") != null) {
-					logger.info("Found Forge mod in " + config + ": {}", id);
-					return true;
-				}
-
-				logger.lifecycle(":could not find forge mod in " + config + " but forcing: {}", id);
-				return true;
-			} else {
-				if (zipFile.getEntry("fabric.mod.json") != null) {
-					logger.info("Found Fabric mod in " + config + ": {}", id);
-					return true;
-				}
-			}
-
-			return false;
-		} catch (IOException e) {
-			return false;
-		}
-	}
-
 	private static void addToRegularCompile(Project project, Configuration regularCompile, ResolvedArtifact artifact) {
 		project.getLogger().info(":providing " + artifact);
 		DependencyHandler dependencies = project.getDependencies();

src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java

@@ -40,8 +40,9 @@ import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.artifacts.ConfigurationContainer;
 import org.gradle.api.tasks.SourceSet;
 
-import net.fabricmc.loom.extension.MixinExtension;
 import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.configuration.ide.idea.IdeaUtils;
+import net.fabricmc.loom.extension.MixinExtension;
 import net.fabricmc.loom.util.Constants;
 
 /**
@@ -85,7 +86,7 @@ public abstract class AnnotationProcessorInvoker<T extends Task> {
 			Path mappings = loom.isForge() ? loom.getMappingsProvider().mixinTinyMappingsWithSrg : loom.getMappingsProvider().tinyMappings;
 			Map<String, String> args = new HashMap<>() {{
 					put(Constants.MixinArguments.IN_MAP_FILE_NAMED_INTERMEDIARY, mappings.toFile().getCanonicalPath());
-					put(Constants.MixinArguments.OUT_MAP_FILE_NAMED_INTERMEDIARY, loom.getNextMixinMappings().getCanonicalPath());
+					put(Constants.MixinArguments.OUT_MAP_FILE_NAMED_INTERMEDIARY, loom.getMixinMappings(sourceSet).getCanonicalPath());
 					put(Constants.MixinArguments.OUT_REFMAP_FILE, getRefmapDestination(task, refmapName));
 					put(Constants.MixinArguments.DEFAULT_OBFUSCATION_ENV, "named:intermediary");
 				}};
@@ -99,9 +100,8 @@ public abstract class AnnotationProcessorInvoker<T extends Task> {
 
 	public void configureMixin() {
 		ConfigurationContainer configs = project.getConfigurations();
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
 
-		if (!extension.ideSync()) {
+		if (!IdeaUtils.isIdeaSync()) {
 			for (Configuration processorConfig : apConfigurations) {
 				project.getLogger().info("Adding mixin to classpath of AP config: " + processorConfig.getName());
 				// Pass named MC classpath to mixin AP classpath

src/main/java/net/fabricmc/loom/build/mixin/JavaApInvoker.java

@@ -58,7 +58,7 @@ public class JavaApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 
 	@Override
 	protected File getRefmapDestinationDir(JavaCompile task) {
-		return task.getDestinationDir();
+		return task.getDestinationDirectory().getAsFile().get();
 	}
 
 	private static String getAptConfigurationName(String sourceSet) {

src/main/java/net/fabricmc/loom/build/mixin/KaptApInvoker.java

@@ -84,7 +84,7 @@ public class KaptApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 				try {
 					String refmapName = Objects.requireNonNull(MixinExtension.getMixinInformationContainer(sourceSet)).refmapNameProvider().get();
 					Path src = Paths.get(getRefmapDestination(task, refmapName));
-					Path dest = Paths.get(task.getDestinationDir().toString(), refmapName);
+					Path dest = Paths.get(task.getDestinationDirectory().get().getAsFile().toString(), refmapName);
 
 					// Possible that no mixin annotations exist
 					if (Files.exists(src)) {

src/main/java/net/fabricmc/loom/build/mixin/ScalaApInvoker.java

@@ -59,6 +59,6 @@ public class ScalaApInvoker extends AnnotationProcessorInvoker<ScalaCompile> {
 
 	@Override
 	protected File getRefmapDestinationDir(ScalaCompile task) {
-		return task.getDestinationDir();
+		return task.getDestinationDirectory().get().getAsFile();
 	}
 }

src/main/java/net/fabricmc/loom/build/nesting/IncludedJarFactory.java

@@ -0,0 +1,212 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.build.nesting;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.charset.StandardCharsets;
+import java.util.Collection;
+import java.util.Locale;
+import java.util.Set;
+
+import com.google.common.collect.Sets;
+import com.google.common.hash.Hashing;
+import com.google.gson.JsonObject;
+import org.apache.commons.io.FileUtils;
+import org.gradle.api.Project;
+import org.gradle.api.Task;
+import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.artifacts.Dependency;
+import org.gradle.api.artifacts.ProjectDependency;
+import org.gradle.api.artifacts.ResolvedArtifact;
+import org.gradle.api.artifacts.ResolvedConfiguration;
+import org.gradle.api.artifacts.ResolvedDependency;
+import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.plugins.JavaPlugin;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.tasks.bundling.AbstractArchiveTask;
+import org.jetbrains.annotations.Nullable;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.LoomGradlePlugin;
+import net.fabricmc.loom.task.RemapTaskConfiguration;
+import net.fabricmc.loom.util.ModUtils;
+import net.fabricmc.loom.util.ZipUtils;
+
+public final class IncludedJarFactory {
+	private final Project project;
+
+	public IncludedJarFactory(Project project) {
+		this.project = project;
+	}
+
+	public Provider<ConfigurableFileCollection> getNestedJars(final Configuration configuration) {
+		return project.provider(() -> {
+			final ConfigurableFileCollection files = project.files();
+			final Set<String> visited = Sets.newHashSet();
+
+			files.from(getProjectDeps(configuration, visited));
+			files.from(getFileDeps(configuration, visited));
+			files.builtBy(configuration.getBuildDependencies());
+			return files;
+		});
+	}
+
+	private ConfigurableFileCollection getFileDeps(Configuration configuration, Set<String> visited) {
+		final ConfigurableFileCollection files = project.files();
+
+		final ResolvedConfiguration resolvedConfiguration = configuration.getResolvedConfiguration();
+		final Set<ResolvedDependency> dependencies = resolvedConfiguration.getFirstLevelModuleDependencies();
+
+		for (ResolvedDependency dependency : dependencies) {
+			if (!visited.add(dependency.getModuleGroup() + ":" + dependency.getModuleName() + ":" + dependency.getModuleVersion())) {
+				continue;
+			}
+
+			for (ResolvedArtifact artifact : dependency.getModuleArtifacts()) {
+				Metadata metadata = new Metadata(
+						dependency.getModuleGroup(),
+						dependency.getModuleName(),
+						dependency.getModuleVersion(),
+						artifact.getClassifier()
+				);
+
+				files.from(project.provider(() -> getNestableJar(artifact.getFile(), metadata)));
+			}
+		}
+
+		return files;
+	}
+
+	private ConfigurableFileCollection getProjectDeps(Configuration configuration, Set<String> visited) {
+		final ConfigurableFileCollection files = project.files();
+
+		for (Dependency dependency : configuration.getDependencies()) {
+			if (dependency instanceof ProjectDependency projectDependency) {
+				if (!visited.add(dependency.getGroup() + ":" + dependency.getName() + ":" + dependency.getVersion())) {
+					continue;
+				}
+
+				// Get the outputs of the project
+				final Project dependentProject = projectDependency.getDependencyProject();
+
+				Collection<Task> remapJarTasks = dependentProject.getTasksByName(RemapTaskConfiguration.REMAP_JAR_TASK_NAME, false);
+				Collection<Task> jarTasks = dependentProject.getTasksByName(JavaPlugin.JAR_TASK_NAME, false);
+
+				if (remapJarTasks.isEmpty() && jarTasks.isEmpty()) {
+					throw new UnsupportedOperationException("%s does not have a remapJar or jar task, cannot nest it".formatted(dependentProject.getName()));
+				}
+
+				for (Task task : remapJarTasks.isEmpty() ? jarTasks : remapJarTasks) {
+					if (task instanceof AbstractArchiveTask archiveTask) {
+						final Metadata metadata = new Metadata(
+								projectDependency.getGroup(),
+								projectDependency.getName(),
+								projectDependency.getVersion(),
+								archiveTask.getArchiveClassifier().getOrNull()
+						);
+
+						Provider<File> provider = archiveTask.getArchiveFile().map(regularFile -> getNestableJar(regularFile.getAsFile(), metadata));
+						files.from(provider);
+						files.builtBy(task);
+					} else {
+						throw new UnsupportedOperationException("Cannot nest none AbstractArchiveTask task: " + task.getName());
+					}
+				}
+			}
+		}
+
+		return files;
+	}
+
+	private File getNestableJar(final File input, final Metadata metadata) {
+		if (ModUtils.isMod(input)) {
+			// Input is a mod, nothing needs to be done.
+			return input;
+		}
+
+		LoomGradleExtension extension = LoomGradleExtension.get(project);
+		File tempDir = new File(extension.getFiles().getUserCache(), "temp/modprocessing");
+
+		if (!tempDir.exists()) {
+			tempDir.mkdirs();
+		}
+
+		File tempFile = new File(tempDir, input.getName());
+
+		if (tempFile.exists()) {
+			tempFile.delete();
+		}
+
+		try {
+			FileUtils.copyFile(input, tempFile);
+			ZipUtils.add(tempFile.toPath(), "fabric.mod.json", generateModForDependency(metadata).getBytes(StandardCharsets.UTF_8));
+		} catch (IOException e) {
+			throw new UncheckedIOException("Failed to add dummy mod while including %s".formatted(input), e);
+		}
+
+		return tempFile;
+	}
+
+	// Generates a barebones mod for a dependency
+	private static String generateModForDependency(Metadata metadata) {
+		String modId = (metadata.group() + "_" + metadata.name() + metadata.classifier())
+				.replaceAll("\\.", "_")
+				.toLowerCase(Locale.ENGLISH);
+
+		// Fabric Loader can't handle modIds longer than 64 characters
+		if (modId.length() > 64) {
+			String hash = Hashing.sha256()
+					.hashString(modId, StandardCharsets.UTF_8)
+					.toString();
+			modId = modId.substring(0, 50) + hash.substring(0, 14);
+		}
+
+		final JsonObject jsonObject = new JsonObject();
+		jsonObject.addProperty("schemaVersion", 1);
+
+		jsonObject.addProperty("id", modId);
+		jsonObject.addProperty("version", metadata.version());
+		jsonObject.addProperty("name", metadata.name());
+
+		JsonObject custom = new JsonObject();
+		custom.addProperty("fabric-loom:generated", true);
+		jsonObject.add("custom", custom);
+
+		return LoomGradlePlugin.GSON.toJson(jsonObject);
+	}
+
+	private record Metadata(String group, String name, String version, @Nullable String classifier) {
+		@Override
+		public String classifier() {
+			if (classifier == null) {
+				return "";
+			} else {
+				return "_" + classifier;
+			}
+		}
+	}
+}

src/main/java/net/fabricmc/loom/build/nesting/JarNester.java

@@ -36,7 +36,7 @@ import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import org.gradle.api.UncheckedIOException;
-import org.gradle.api.logging.Logger;
+import org.slf4j.Logger;
 
 import net.fabricmc.loom.util.ModUtils;
 import net.fabricmc.loom.util.Pair;
@@ -69,6 +69,7 @@ public class JarNester {
 
 				for (File file : jars) {
 					String nestedJarPath = "META-INF/jars/" + file.getName();
+					Preconditions.checkArgument(ModUtils.isMod(file), "Cannot nest none mod jar: " + file.getName());
 
 					for (JsonElement nestedJar : nestedJars) {
 						JsonObject jsonObject = nestedJar.getAsJsonObject();

src/main/java/net/fabricmc/loom/build/nesting/NestedDependencyProvider.java

@@ -1,281 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2019-2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.build.nesting;
-
-import java.io.File;
-import java.io.IOException;
-import java.io.UncheckedIOException;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Locale;
-import java.util.Set;
-
-import javax.annotation.Nullable;
-
-import com.google.gson.JsonObject;
-import org.apache.commons.io.FileUtils;
-import org.gradle.api.Project;
-import org.gradle.api.Task;
-import org.gradle.api.artifacts.Configuration;
-import org.gradle.api.artifacts.Dependency;
-import org.gradle.api.artifacts.DependencySet;
-import org.gradle.api.artifacts.ProjectDependency;
-import org.gradle.api.artifacts.ResolvedArtifact;
-import org.gradle.api.artifacts.ResolvedConfiguration;
-import org.gradle.api.artifacts.ResolvedDependency;
-import org.gradle.api.tasks.bundling.AbstractArchiveTask;
-
-import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.LoomGradlePlugin;
-import net.fabricmc.loom.task.RemapJarTask;
-import net.fabricmc.loom.util.Constants;
-import net.fabricmc.loom.util.ZipUtils;
-
-public final class NestedDependencyProvider implements NestedJarProvider {
-	final Project project;
-	final List<DependencyInfo<?>> files;
-
-	private NestedDependencyProvider(Project project, List<DependencyInfo<?>> files) {
-		this.project = project;
-		this.files = files;
-	}
-
-	public static NestedDependencyProvider createNestedDependencyProviderFromConfiguration(Project project, Configuration configuration) {
-		List<DependencyInfo<?>> fileList = new ArrayList<>();
-		Set<String> visited = new HashSet<>();
-
-		fileList.addAll(populateProjectDependencies(configuration, visited));
-		fileList.addAll(populateResolvedDependencies(configuration, visited));
-
-		return new NestedDependencyProvider(project, fileList);
-	}
-
-	// Looks for any deps that require a sub project to be built first
-	public static List<RemapJarTask> getRequiredTasks(Project project) {
-		List<RemapJarTask> remapTasks = new ArrayList<>();
-
-		Configuration configuration = project.getConfigurations().getByName(Constants.Configurations.INCLUDE);
-		DependencySet dependencies = configuration.getDependencies();
-
-		for (Dependency dependency : dependencies) {
-			if (dependency instanceof ProjectDependency projectDependency) {
-				Project dependencyProject = projectDependency.getDependencyProject();
-
-				for (Task task : dependencyProject.getTasksByName("remapJar", false)) {
-					if (task instanceof RemapJarTask remapJarTask) {
-						remapTasks.add(remapJarTask);
-					}
-				}
-			}
-		}
-
-		return remapTasks;
-	}
-
-	private static List<DependencyInfo<ProjectDependency>> populateProjectDependencies(Configuration configuration, Set<String> visited) {
-		List<DependencyInfo<ProjectDependency>> fileList = new ArrayList<>();
-
-		for (Dependency dependency : configuration.getDependencies()) {
-			if (dependency instanceof ProjectDependency projectDependency) {
-				Project dependencyProject = projectDependency.getDependencyProject();
-
-				visited.add(dependency.getGroup() + ":" + dependency.getName() + ":" + dependency.getVersion());
-
-				Collection<Task> remapJarTasks = dependencyProject.getTasksByName("remapJar", false);
-				Collection<Task> jarTasks = dependencyProject.getTasksByName("jar", false);
-
-				for (Task task : remapJarTasks.isEmpty() ? jarTasks : remapJarTasks) {
-					if (task instanceof AbstractArchiveTask abstractArchiveTask) {
-						fileList.add(new DependencyInfo<>(
-								projectDependency,
-								new ProjectDependencyMetaExtractor(),
-								abstractArchiveTask.getArchiveFile().get().getAsFile(),
-								abstractArchiveTask.getArchiveClassifier().getOrNull()
-						));
-					}
-				}
-			}
-		}
-
-		return fileList;
-	}
-
-	private static List<DependencyInfo<ResolvedDependency>> populateResolvedDependencies(Configuration configuration, Set<String> visited) {
-		ResolvedConfiguration resolvedConfiguration = configuration.getResolvedConfiguration();
-		Set<ResolvedDependency> dependencies = resolvedConfiguration.getFirstLevelModuleDependencies();
-
-		List<DependencyInfo<ResolvedDependency>> fileList = new ArrayList<>();
-
-		for (ResolvedDependency dependency : dependencies) {
-			if (visited.contains(dependency.getModuleGroup() + ":" + dependency.getModuleName() + ":" + dependency.getModuleVersion())) {
-				continue;
-			}
-
-			for (ResolvedArtifact artifact : dependency.getModuleArtifacts()) {
-				fileList.add(new DependencyInfo<>(
-						dependency,
-						new ResolvedDependencyMetaExtractor(),
-						artifact.getFile(),
-						artifact.getClassifier()
-				));
-			}
-		}
-
-		return fileList;
-	}
-
-	@Override
-	public List<File> provide() {
-		List<File> fileList = new ArrayList<>();
-
-		for (DependencyInfo<?> metaFile : files) {
-			metaFile.validateInputs();
-
-			File file = metaFile.file;
-
-			//A lib that doesnt have a mod.json, we turn it into a fake mod
-			if (!ZipUtils.contains(file.toPath(), "fabric.mod.json")) {
-				LoomGradleExtension extension = LoomGradleExtension.get(project);
-				File tempDir = new File(extension.getFiles().getUserCache(), "temp/modprocessing");
-
-				if (!tempDir.exists()) {
-					tempDir.mkdirs();
-				}
-
-				File tempFile = new File(tempDir, file.getName());
-
-				if (tempFile.exists()) {
-					tempFile.delete();
-				}
-
-				try {
-					FileUtils.copyFile(file, tempFile);
-				} catch (IOException e) {
-					throw new RuntimeException("Failed to copy file", e);
-				}
-
-				try {
-					ZipUtils.add(tempFile.toPath(), "fabric.mod.json", generateModForDependency(metaFile).getBytes());
-				} catch (IOException e) {
-					throw new UncheckedIOException("Failed to add dummy mod while including %s".formatted(file), e);
-				}
-
-				fileList.add(tempFile);
-			} else {
-				// Default copy the jar right in
-				fileList.add(file);
-			}
-		}
-
-		return fileList;
-	}
-
-	// Generates a barebones mod for a dependency
-	private static <D> String generateModForDependency(DependencyInfo<D> info) {
-		DependencyMetaExtractor<D> metaExtractor = info.metaExtractor;
-		D dependency = info.dependency;
-
-		JsonObject jsonObject = new JsonObject();
-		jsonObject.addProperty("schemaVersion", 1);
-
-		jsonObject.addProperty("id",
-				(metaExtractor.group(dependency) + "_" + metaExtractor.name(dependency) + info.getClassifierSuffix())
-						.replaceAll("\\.", "_")
-						.toLowerCase(Locale.ENGLISH)
-		);
-		jsonObject.addProperty("version", metaExtractor.version(dependency));
-		jsonObject.addProperty("name", metaExtractor.name(dependency));
-
-		JsonObject custom = new JsonObject();
-		custom.addProperty("fabric-loom:generated", true);
-		jsonObject.add("custom", custom);
-
-		return LoomGradlePlugin.GSON.toJson(jsonObject);
-	}
-
-	private record DependencyInfo<D>(D dependency, DependencyMetaExtractor<D> metaExtractor, File file, @Nullable String classifier) {
-		void validateInputs() {
-			if (!file.exists()) {
-				throw new RuntimeException("Failed to include nested jars, as it could not be found @ " + file.getAbsolutePath());
-			}
-
-			if (file.isDirectory() || !file.getName().endsWith(".jar")) {
-				throw new RuntimeException("Failed to include nested jars, as file was not a jar: " + file.getAbsolutePath());
-			}
-		}
-
-		String getClassifierSuffix() {
-			if (classifier == null) {
-				return "";
-			} else {
-				return "_" + classifier;
-			}
-		}
-	}
-
-	private interface DependencyMetaExtractor<D> {
-		String group(D dependency);
-
-		String version(D dependency);
-
-		String name(D dependency);
-	}
-
-	private static final class ProjectDependencyMetaExtractor implements DependencyMetaExtractor<ProjectDependency> {
-		@Override
-		public String group(ProjectDependency dependency) {
-			return dependency.getGroup();
-		}
-
-		@Override
-		public String version(ProjectDependency dependency) {
-			return dependency.getVersion();
-		}
-
-		@Override
-		public String name(ProjectDependency dependency) {
-			return dependency.getName();
-		}
-	}
-
-	private static final class ResolvedDependencyMetaExtractor implements DependencyMetaExtractor<ResolvedDependency> {
-		@Override
-		public String group(ResolvedDependency dependency) {
-			return dependency.getModuleGroup();
-		}
-
-		@Override
-		public String version(ResolvedDependency dependency) {
-			return dependency.getModuleVersion();
-		}
-
-		@Override
-		public String name(ResolvedDependency dependency) {
-			return dependency.getModuleName();
-		}
-	}
-}

src/main/java/net/fabricmc/loom/build/nesting/NestedJarPathProvider.java

@@ -1,69 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2016-2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.build.nesting;
-
-import java.io.File;
-import java.util.Collection;
-import java.util.Set;
-
-import com.google.common.base.Preconditions;
-import org.gradle.api.Project;
-
-import net.fabricmc.loom.util.ModUtils;
-
-public final class NestedJarPathProvider implements NestedJarProvider {
-	private final Set<Object> nestedPaths;
-	private Set<File> files = null;
-	public NestedJarPathProvider(Set<Object> nestedPaths) {
-		this.nestedPaths = nestedPaths;
-	}
-
-	private Set<File> resolve(Project project) {
-		return project.files(nestedPaths).getFiles();
-	}
-
-	@Override
-	public void prepare(Project project) {
-		if (files == null) {
-			files = resolve(project);
-		}
-	}
-
-	@Override
-	public Collection<File> provide() {
-		validateFiles();
-		return files;
-	}
-
-	private void validateFiles() {
-		Preconditions.checkNotNull(files, "null files to nest, was prepare called?");
-
-		for (File file : files) {
-			Preconditions.checkArgument(file.getName().endsWith(".jar"), String.format("Tried to nest %s but it is not a jar", file.getAbsolutePath()));
-			Preconditions.checkArgument(file.exists(), String.format("Tried to nest jar %s but it does not exist", file.getAbsolutePath()));
-			Preconditions.checkArgument(ModUtils.isMod(file), String.format("Cannot use nest none mod jar %s", file.getAbsolutePath()));
-		}
-	}
-}

src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java

@@ -24,22 +24,24 @@
 
 package net.fabricmc.loom.configuration;
 
+import java.io.File;
 import java.nio.charset.StandardCharsets;
 
+import org.gradle.api.NamedDomainObjectProvider;
 import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.plugins.JavaPlugin;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.JavaPluginExtension;
 import org.gradle.api.tasks.AbstractCopyTask;
 import org.gradle.api.tasks.SourceSet;
+import org.gradle.api.tasks.TaskContainer;
 import org.gradle.api.tasks.compile.JavaCompile;
 import org.gradle.api.tasks.javadoc.Javadoc;
-import org.gradle.jvm.tasks.Jar;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.build.mixin.JavaApInvoker;
 import net.fabricmc.loom.build.mixin.KaptApInvoker;
 import net.fabricmc.loom.build.mixin.ScalaApInvoker;
-import net.fabricmc.loom.configuration.ide.SetupIntelijRunConfigs;
 import net.fabricmc.loom.configuration.providers.LaunchProvider;
 import net.fabricmc.loom.configuration.providers.MinecraftProviderImpl;
 import net.fabricmc.loom.configuration.providers.forge.FieldMigratedMappingsProvider;
@@ -51,7 +53,9 @@ import net.fabricmc.loom.configuration.providers.forge.PatchProvider;
 import net.fabricmc.loom.configuration.providers.forge.SrgProvider;
 import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
 import net.fabricmc.loom.extension.MixinExtension;
+import net.fabricmc.loom.task.GenerateSourcesTask;
 import net.fabricmc.loom.task.GenVsCodeProjectTask;
+import net.fabricmc.loom.task.UnpickJarTask;
 import net.fabricmc.loom.util.Constants;
 
 public final class CompileConfiguration {
@@ -73,12 +77,17 @@ public final class CompileConfiguration {
 			}
 		});
 
-		extension.createLazyConfiguration(Constants.Configurations.MOD_COMPILE_CLASSPATH).configure(configuration -> configuration.setTransitive(true));
-		extension.createLazyConfiguration(Constants.Configurations.MOD_COMPILE_CLASSPATH_MAPPED).configure(configuration -> configuration.setTransitive(false));
-		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_NAMED).configure(configuration -> configuration.setTransitive(false)); // The launchers do not recurse dependencies
-		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_DEPENDENCIES).configure(configuration -> configuration.setTransitive(false));
-		extension.createLazyConfiguration(Constants.Configurations.LOADER_DEPENDENCIES).configure(configuration -> configuration.setTransitive(false));
-		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT).configure(configuration -> configuration.setTransitive(false));
+		extension.createLazyConfiguration(Constants.Configurations.MOD_COMPILE_CLASSPATH, configuration -> configuration.setTransitive(true));
+		extension.createLazyConfiguration(Constants.Configurations.MOD_COMPILE_CLASSPATH_MAPPED, configuration -> configuration.setTransitive(false));
+		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_NAMED, configuration -> configuration.setTransitive(false)); // The launchers do not recurse dependencies
+		NamedDomainObjectProvider<Configuration> serverDeps = extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_SERVER_DEPENDENCIES, configuration -> configuration.setTransitive(false));
+		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_DEPENDENCIES, configuration -> {
+			configuration.extendsFrom(serverDeps.get());
+			configuration.setTransitive(false);
+		});
+		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT_NATIVES, configuration -> configuration.setTransitive(false));
+		extension.createLazyConfiguration(Constants.Configurations.LOADER_DEPENDENCIES, configuration -> configuration.setTransitive(false));
+		extension.createLazyConfiguration(Constants.Configurations.MINECRAFT, configuration -> configuration.setTransitive(false));
 
 		if (extension.isForge()) {
 			extension.createLazyConfiguration(Constants.Configurations.FORGE).configure(configuration -> configuration.setTransitive(false));
@@ -113,11 +122,10 @@ public final class CompileConfiguration {
 		}
 
 		if (extension.supportsInclude()) {
-			extension.createLazyConfiguration(Constants.Configurations.INCLUDE).configure(configuration -> configuration.setTransitive(false)); // Dont get transitive deps
+			extension.createLazyConfiguration(Constants.Configurations.INCLUDE, configuration -> configuration.setTransitive(false)); // Dont get transitive deps
 		}
-
 		extension.createLazyConfiguration(Constants.Configurations.MAPPING_CONSTANTS);
-		extension.createLazyConfiguration(Constants.Configurations.NAMED_ELEMENTS).configure(configuration -> {
+		extension.createLazyConfiguration(Constants.Configurations.NAMED_ELEMENTS, configuration -> {
 			configuration.setCanBeConsumed(true);
 			configuration.setCanBeResolved(false);
 			configuration.extendsFrom(project.getConfigurations().getByName(JavaPlugin.API_CONFIGURATION_NAME));
@@ -173,16 +181,15 @@ public final class CompileConfiguration {
 	}
 
 	public static void configureCompile(Project p) {
-		JavaPluginConvention javaModule = (JavaPluginConvention) p.getConvention().getPlugins().get("java");
+		final JavaPluginExtension javaPluginExtension = p.getExtensions().getByType(JavaPluginExtension.class);
+		LoomGradleExtension extension = LoomGradleExtension.get(p);
 
-		SourceSet main = javaModule.getSourceSets().getByName(SourceSet.MAIN_SOURCE_SET_NAME);
-
-		Javadoc javadoc = (Javadoc) p.getTasks().getByName(JavaPlugin.JAVADOC_TASK_NAME);
-		javadoc.setClasspath(main.getOutput().plus(main.getCompileClasspath()));
+		p.getTasks().named(JavaPlugin.JAVADOC_TASK_NAME, Javadoc.class).configure(javadoc -> {
+			final SourceSet main = javaPluginExtension.getSourceSets().getByName(SourceSet.MAIN_SOURCE_SET_NAME);
+			javadoc.setClasspath(main.getOutput().plus(main.getCompileClasspath()));
+		});
 
 		p.afterEvaluate(project -> {
-			LoomGradleExtension extension = LoomGradleExtension.get(project);
-
 			LoomDependencyManager dependencyManager = new LoomDependencyManager();
 			extension.setDependencyManager(dependencyManager);
 
@@ -208,31 +215,23 @@ public final class CompileConfiguration {
 
 			dependencyManager.handleDependencies(project);
 
-			project.getTasks().getByName("idea").finalizedBy(project.getTasks().getByName("genIdeaWorkspace"));
-			project.getTasks().getByName("eclipse").finalizedBy(project.getTasks().getByName("genEclipseRuns"));
-			project.getTasks().getByName("cleanEclipse").finalizedBy(project.getTasks().getByName("cleanEclipseRuns"));
-
-			SetupIntelijRunConfigs.setup(project);
-			GenVsCodeProjectTask.generate(project);
 			extension.getRemapArchives().finalizeValue();
 
-			// Enables the default mod remapper
-			if (extension.getRemapArchives().get()) {
-				RemapConfiguration.setupDefaultRemap(project);
-			} else {
-				Jar jarTask = (Jar) project.getTasks().getByName("jar");
-				extension.getUnmappedModCollection().from(jarTask);
-			}
-
 			MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 
 			if (mixin.getUseLegacyMixinAp().get()) {
 				setupMixinAp(project, mixin);
 			}
+
+			configureDecompileTasks(project);
 		});
 
+		finalizedBy(p, "idea", "genIdeaWorkspace");
+		finalizedBy(p, "eclipse", "genEclipseRuns");
+		finalizedBy(p, "cleanEclipse", "cleanEclipseRuns");
+
 		// Add the "dev" jar to the "namedElements" configuration
-		p.artifacts(artifactHandler -> artifactHandler.add(Constants.Configurations.NAMED_ELEMENTS, p.getTasks().getByName("jar")));
+		p.artifacts(artifactHandler -> artifactHandler.add(Constants.Configurations.NAMED_ELEMENTS, p.getTasks().named("jar")));
 
 		// Ensure that the encoding is set to UTF-8, no matter what the system default is
 		// this fixes some edge cases with special characters not displaying correctly
@@ -269,7 +268,47 @@ public final class CompileConfiguration {
 		}
 	}
 
+	private static void configureDecompileTasks(Project project) {
+		final TaskContainer tasks = project.getTasks();
+		final LoomGradleExtension extension = LoomGradleExtension.get(project);
+
+		MappingsProviderImpl mappingsProvider = extension.getMappingsProvider();
+
+		File mappedJar = mappingsProvider.mappedProvider.getMappedJar();
+
+		if (mappingsProvider.hasUnpickDefinitions()) {
+			File outputJar = mappingsProvider.mappedProvider.getUnpickedJar();
+
+			tasks.register("unpickJar", UnpickJarTask.class, unpickJarTask -> {
+				unpickJarTask.getUnpickDefinitions().set(mappingsProvider.getUnpickDefinitionsFile());
+				unpickJarTask.getInputJar().set(mappingsProvider.mappedProvider.getMappedJar());
+				unpickJarTask.getOutputJar().set(outputJar);
+			});
+
+			mappedJar = outputJar;
+		}
+
+		final File inputJar = mappedJar;
+
+		extension.getGameDecompilers().configureEach(decompiler -> {
+			String taskName = "genSourcesWith" + decompiler.name();
+
+			// Set the input jar for the task after evaluation has occurred.
+			tasks.named(taskName, GenerateSourcesTask.class).configure(task -> {
+				task.getInputJar().set(inputJar);
+
+				if (mappingsProvider.hasUnpickDefinitions()) {
+					task.dependsOn(tasks.named("unpickJar"));
+				}
+			});
+		});
+	}
+
 	private static void extendsFrom(String a, String b, Project project) {
 		project.getConfigurations().getByName(a, configuration -> configuration.extendsFrom(project.getConfigurations().getByName(b)));
 	}
+
+	private static void finalizedBy(Project project, String a, String b) {
+		project.getTasks().named(a).configure(task -> task.finalizedBy(project.getTasks().named(b)));
+	}
 }

src/main/java/net/fabricmc/loom/configuration/JarManifestConfiguration.java

@@ -1,92 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.configuration;
-
-import java.util.Optional;
-import java.util.jar.Attributes;
-import java.util.jar.Manifest;
-
-import dev.architectury.tinyremapper.TinyRemapper;
-import org.gradle.api.Project;
-import org.gradle.api.artifacts.Dependency;
-import org.gradle.util.GradleVersion;
-
-import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.LoomGradlePlugin;
-import net.fabricmc.loom.util.Constants;
-
-public final record JarManifestConfiguration(Project project) {
-	public void configure(Manifest manifest) {
-		// Dont set when running the reproducible build tests as it will break them when anything updates
-		if (Boolean.getBoolean("loom.test.reproducible")) {
-			return;
-		}
-
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-
-		Attributes attributes = manifest.getMainAttributes();
-		Optional<String> tinyRemapperVersion = Optional.ofNullable(TinyRemapper.class.getPackage().getImplementationVersion());
-
-		attributes.putValue("Fabric-Gradle-Version", GradleVersion.current().getVersion());
-		attributes.putValue("Fabric-Loom-Version", LoomGradlePlugin.LOOM_VERSION);
-		attributes.putValue("Fabric-Mixin-Compile-Extensions-Version", Constants.Dependencies.Versions.MIXIN_COMPILE_EXTENSIONS);
-		attributes.putValue("Fabric-Minecraft-Version", extension.getMinecraftProvider().minecraftVersion());
-		tinyRemapperVersion.ifPresent(s -> attributes.putValue("Fabric-Tiny-Remapper-Version", s));
-		getLoaderVersion().ifPresent(s -> attributes.putValue("Fabric-Loader-Version", s));
-
-		// This can be overridden by mods if required
-		if (!attributes.containsKey("Fabric-Mixin-Version")) {
-			addMixinVersion(attributes);
-		}
-	}
-
-	private void addMixinVersion(Attributes attributes) {
-		// Not super ideal that this uses the mod compile classpath, should prob look into making this not a thing at somepoint
-		Optional<Dependency> dependency = project.getConfigurations().getByName(Constants.Configurations.LOADER_DEPENDENCIES)
-				.getDependencies()
-				.stream()
-				.filter(dep -> "sponge-mixin".equals(dep.getName()))
-				.findFirst();
-
-		if (dependency.isEmpty()) {
-			project.getLogger().warn("Could not determine Mixin version for jar manifest");
-			return;
-		}
-
-		attributes.putValue("Fabric-Mixin-Version", dependency.get().getVersion());
-		attributes.putValue("Fabric-Mixin-Group", dependency.get().getGroup());
-	}
-
-	private Optional<String> getLoaderVersion() {
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-
-		if (extension.getInstallerData() == null) {
-			project.getLogger().warn("Could not determine fabric loader version for jar manifest");
-			return Optional.empty();
-		}
-
-		return Optional.of(extension.getInstallerData().version());
-	}
-}

src/main/java/net/fabricmc/loom/configuration/LoomDependencyManager.java

@@ -46,6 +46,7 @@ import net.fabricmc.loom.LoomGradlePlugin;
 import net.fabricmc.loom.LoomRepositoryPlugin;
 import net.fabricmc.loom.build.ModCompileRemapper;
 import net.fabricmc.loom.configuration.DependencyProvider.DependencyInfo;
+import net.fabricmc.loom.configuration.ide.idea.IdeaUtils;
 import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
 import net.fabricmc.loom.util.Constants;
 import net.fabricmc.loom.util.SourceRemapper;
@@ -210,7 +211,7 @@ public class LoomDependencyManager {
 			loaderDepsConfig.getDependencies().add(modDep);
 
 			// TODO: work around until https://github.com/FabricMC/Mixin/pull/60 and https://github.com/FabricMC/fabric-mixin-compile-extensions/issues/14 is fixed.
-			if (!extension.ideSync() && extension.getMixin().getUseLegacyMixinAp().get()) {
+			if (!IdeaUtils.isIdeaSync() && extension.getMixin().getUseLegacyMixinAp().get()) {
 				apDepsConfig.getDependencies().add(modDep);
 			}
 

src/main/java/net/fabricmc/loom/configuration/RemapConfiguration.java

@@ -1,249 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.configuration;
-
-import java.io.IOException;
-import java.util.Set;
-
-import com.google.common.base.Preconditions;
-import com.google.common.collect.ImmutableMap;
-import org.gradle.api.Action;
-import org.gradle.api.Project;
-import org.gradle.api.Task;
-import org.gradle.api.UnknownTaskException;
-import org.gradle.api.artifacts.ConfigurablePublishArtifact;
-import org.gradle.api.artifacts.Configuration;
-import org.gradle.api.artifacts.PublishArtifact;
-import org.gradle.api.artifacts.dsl.ArtifactHandler;
-import org.gradle.api.plugins.JavaPlugin;
-import org.gradle.api.tasks.bundling.AbstractArchiveTask;
-import org.gradle.api.tasks.bundling.Jar;
-import org.jetbrains.annotations.ApiStatus;
-
-import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.build.JarRemapper;
-import net.fabricmc.loom.build.nesting.NestedDependencyProvider;
-import net.fabricmc.loom.task.AbstractLoomTask;
-import net.fabricmc.loom.task.RemapAllSourcesTask;
-import net.fabricmc.loom.task.RemapJarTask;
-import net.fabricmc.loom.task.RemapSourcesJarTask;
-import net.fabricmc.loom.util.PropertyUtil;
-import net.fabricmc.loom.util.SourceRemapper;
-import net.fabricmc.loom.util.aw2at.Aw2At;
-
-public class RemapConfiguration {
-	private static final String DEFAULT_JAR_TASK_NAME = JavaPlugin.JAR_TASK_NAME;
-	private static final String DEFAULT_SOURCES_JAR_TASK_NAME = "sourcesJar";
-	private static final String DEFAULT_REMAP_JAR_TASK_NAME = "remapJar";
-	private static final String DEFAULT_REMAP_SOURCES_JAR_TASK_NAME = "remapSourcesJar";
-	private static final String DEFAULT_REMAP_ALL_JARS_TASK_NAME = "remapAllJars";
-	private static final String DEFAULT_REMAP_ALL_SOURCES_TASK_NAME = "remapAllSources";
-
-	public static void setupDefaultRemap(Project project) {
-		setupRemap(project, true, DEFAULT_JAR_TASK_NAME, DEFAULT_SOURCES_JAR_TASK_NAME, DEFAULT_REMAP_JAR_TASK_NAME, DEFAULT_REMAP_SOURCES_JAR_TASK_NAME, DEFAULT_REMAP_ALL_JARS_TASK_NAME, DEFAULT_REMAP_ALL_SOURCES_TASK_NAME);
-
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-		extension.getSetupRemappedVariants().finalizeValue();
-
-		if (extension.getSetupRemappedVariants().get()) {
-			ArtifactHandler artifacts = project.getArtifacts();
-			project.getTasks().named(DEFAULT_REMAP_JAR_TASK_NAME, task -> {
-				artifacts.add(JavaPlugin.API_ELEMENTS_CONFIGURATION_NAME, task, artifactConfigurationAction(task, DEFAULT_REMAP_JAR_TASK_NAME, project));
-				artifacts.add(JavaPlugin.RUNTIME_ELEMENTS_CONFIGURATION_NAME, task, artifactConfigurationAction(task, DEFAULT_REMAP_JAR_TASK_NAME, project));
-			});
-			project.getTasks().named(DEFAULT_REMAP_SOURCES_JAR_TASK_NAME, RemapSourcesJarTask.class, task -> {
-				if (!project.getConfigurations().getNames().contains(JavaPlugin.SOURCES_ELEMENTS_CONFIGURATION_NAME)) {
-					// Sources jar may not have been created with withSourcesJar
-					project.getLogger().info("Not publishing sources jar as it was not found. Use java.withSourcesJar() to fix.");
-					return;
-				}
-
-				PublishArtifact artifact = artifacts.add(JavaPlugin.SOURCES_ELEMENTS_CONFIGURATION_NAME, task.getOutput(), artifactConfigurationAction(task, DEFAULT_REMAP_ALL_SOURCES_TASK_NAME, project));
-
-				// Remove the existing artifact that does not run remapSourcesJar.
-				// It doesn't seem to hurt, but I'm not sure if the file-level duplicates cause issues.
-				Configuration configuration = project.getConfigurations().getByName(JavaPlugin.SOURCES_ELEMENTS_CONFIGURATION_NAME);
-				configuration.getArtifacts().removeIf(a -> a != artifact && artifact.getFile().equals(a.getFile()));
-				// Architectury Loom Patch
-				// Since we make sourcesJar and remapSourcesJar output files separate, we have to remove the dev sources jar file here
-				configuration.getArtifacts().removeIf(a -> a != artifact && task.getInput().get().getAsFile().equals(a.getFile()));
-			});
-
-			// Remove -dev jars from the default jar task
-			for (String configurationName : new String[] { JavaPlugin.API_ELEMENTS_CONFIGURATION_NAME, JavaPlugin.RUNTIME_ELEMENTS_CONFIGURATION_NAME }) {
-				Configuration configuration = project.getConfigurations().getByName(configurationName);
-				configuration.getArtifacts().removeIf(artifact -> {
-					Task jarTask = project.getTasks().getByName(DEFAULT_JAR_TASK_NAME);
-					// if the artifact is a -dev jar and "builtBy jar"
-					return "dev".equals(artifact.getClassifier()) && artifact.getBuildDependencies().getDependencies(null).contains(jarTask);
-				});
-			}
-		}
-	}
-
-	@ApiStatus.Experimental // This is only an api if you squint really hard, expect it to explode every 5 mins. If you must call in afterEvaluate on all projects
-	public static void setupRemap(Project project, String jarTaskName, String sourcesJarTaskName, String remapJarTaskName, String remapSourcesJarTaskName, String remapAllJarsTaskName, String remapAllSourcesTaskName) {
-		setupRemap(project, false, jarTaskName, sourcesJarTaskName, remapJarTaskName, remapSourcesJarTaskName, remapAllJarsTaskName, remapAllSourcesTaskName);
-	}
-
-	// isDefaultRemap is set to true for the standard remap task, some defaults are left out when this is false.
-	private static void setupRemap(Project project, boolean isDefaultRemap, String jarTaskName, String sourcesJarTaskName, String remapJarTaskName, String remapSourcesJarTaskName, String remapAllJarsTaskName, String remapAllSourcesTaskName) {
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-		AbstractArchiveTask jarTask = (AbstractArchiveTask) project.getTasks().getByName(jarTaskName);
-		RemapJarTask remapJarTask = (RemapJarTask) project.getTasks().findByName(remapJarTaskName);
-
-		assert remapJarTask != null;
-
-		if (!remapJarTask.getInput().isPresent() && isDefaultRemap) {
-			jarTask.getArchiveClassifier().convention("dev");
-			remapJarTask.getArchiveClassifier().convention("");
-			remapJarTask.getInput().convention(jarTask.getArchiveFile());
-		}
-
-		if (extension.isForge()) {
-			Set<String> mixinConfigs = PropertyUtil.getAndFinalize(extension.getForge().getMixinConfigs());
-
-			if (!mixinConfigs.isEmpty()) {
-				((Jar) jarTask).manifest(manifest -> {
-					manifest.attributes(ImmutableMap.of("MixinConfigs", String.join(",", mixinConfigs)));
-				});
-			}
-		}
-
-		if (isDefaultRemap) {
-			extension.getUnmappedModCollection().from(jarTask);
-			remapJarTask.getAddNestedDependencies().convention(true);
-			remapJarTask.getRemapAccessWidener().convention(true);
-
-			project.getArtifacts().add("archives", remapJarTask);
-
-			if (extension.isForge()) {
-				boolean convertAws = PropertyUtil.getAndFinalize(extension.getForge().getConvertAccessWideners());
-
-				if (convertAws) {
-					Aw2At.setup(project, remapJarTask);
-					remapJarTask.getRemapAccessWidener().set(false);
-				}
-			}
-		}
-
-		remapJarTask.dependsOn(jarTask);
-		project.getTasks().getByName("build").dependsOn(remapJarTask);
-
-		// TODO this might be wrong?
-		project.getTasks().withType(RemapJarTask.class).forEach(task -> {
-			if (extension.supportsInclude() && task.getAddNestedDependencies().getOrElse(false)) {
-				NestedDependencyProvider.getRequiredTasks(project).forEach(task::dependsOn);
-			}
-		});
-
-		SourceRemapper remapper = null;
-		// TODO what is this for?
-		Task parentTask = project.getTasks().getByName("build");
-
-		if (extension.getShareRemapCaches().get()) {
-			Project rootProject = project.getRootProject();
-
-			if (extension.isRootProject()) {
-				SourceRemapper sourceRemapper = new SourceRemapper(rootProject, false);
-				JarRemapper jarRemapper = new JarRemapper();
-
-				remapJarTask.jarRemapper = jarRemapper;
-
-				rootProject.getTasks().register(remapAllSourcesTaskName, RemapAllSourcesTask.class, task -> {
-					task.sourceRemapper = sourceRemapper;
-					task.doLast(t -> sourceRemapper.remapAll());
-				});
-
-				parentTask = rootProject.getTasks().getByName(remapAllSourcesTaskName);
-
-				rootProject.getTasks().register(remapAllJarsTaskName, AbstractLoomTask.class, task -> {
-					task.doLast(t -> {
-						try {
-							jarRemapper.remap(project);
-						} catch (IOException e) {
-							throw new RuntimeException("Failed to remap jars", e);
-						}
-					});
-				});
-			} else {
-				parentTask = rootProject.getTasks().getByName(remapAllSourcesTaskName);
-				remapper = ((RemapAllSourcesTask) parentTask).sourceRemapper;
-				Preconditions.checkNotNull(remapper);
-
-				remapJarTask.jarRemapper = ((RemapJarTask) rootProject.getTasks().getByName(remapJarTaskName)).jarRemapper;
-
-				project.getTasks().getByName("build").dependsOn(parentTask);
-				project.getTasks().getByName("build").dependsOn(rootProject.getTasks().getByName(remapAllJarsTaskName));
-				rootProject.getTasks().getByName(remapAllJarsTaskName).dependsOn(project.getTasks().getByName(remapJarTaskName));
-			}
-		}
-
-		try {
-			AbstractArchiveTask sourcesTask = (AbstractArchiveTask) project.getTasks().getByName(sourcesJarTaskName);
-
-			RemapSourcesJarTask remapSourcesJarTask = (RemapSourcesJarTask) project.getTasks().findByName(remapSourcesJarTaskName);
-			Preconditions.checkNotNull(remapSourcesJarTask, "Could not find " + remapSourcesJarTaskName + " in " + project.getName());
-			remapSourcesJarTask.getOutput().convention(sourcesTask.getArchiveFile().get());
-			String sourcesTaskClassifer = sourcesTask.getArchiveClassifier().get();
-			sourcesTask.getArchiveClassifier().set(sourcesTaskClassifer == null ? "dev" : sourcesTaskClassifer + "-dev");
-			remapSourcesJarTask.getInput().convention(sourcesTask.getArchiveFile());
-			remapSourcesJarTask.dependsOn(sourcesTask);
-
-			if (isDefaultRemap) {
-				// Do not use lambda here, see: https://github.com/gradle/gradle/pull/17087
-				//noinspection Convert2Lambda
-				remapSourcesJarTask.doLast(new Action<>() {
-					@Override
-					public void execute(Task task) {
-						project.getArtifacts().add("archives", remapSourcesJarTask.getOutput());
-					}
-				});
-			}
-
-			if (extension.getShareRemapCaches().get()) {
-				remapSourcesJarTask.setSourceRemapper(remapper);
-			}
-
-			parentTask.dependsOn(remapSourcesJarTask);
-		} catch (UnknownTaskException ignored) {
-			// pass
-		}
-	}
-
-	private static Action<ConfigurablePublishArtifact> artifactConfigurationAction(Task standardTask, String sharedTaskName, Project project) {
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-
-		return artifact -> {
-			Task remapTask = standardTask;
-
-			if (extension.getShareRemapCaches().get()) {
-				remapTask = project.getRootProject().getTasks().getByName(sharedTaskName);
-			}
-
-			artifact.builtBy(remapTask);
-		};
-	}
-}

src/main/java/net/fabricmc/loom/configuration/accesswidener/AccessWidenerFile.java

@@ -37,7 +37,7 @@ import com.google.gson.JsonObject;
 import net.fabricmc.loom.util.ZipUtils;
 
 public record AccessWidenerFile(
-		String name,
+		String path,
 		String modId,
 		byte[] content
 ) {
@@ -121,7 +121,7 @@ public record AccessWidenerFile(
 
 	@Override
 	public int hashCode() {
-		int result = Objects.hash(name, modId);
+		int result = Objects.hash(path, modId);
 		result = 31 * result + Arrays.hashCode(content);
 		return result;
 	}

src/main/java/net/fabricmc/loom/configuration/accesswidener/AccessWidenerJarProcessor.java

@@ -34,14 +34,10 @@ import java.util.Arrays;
 
 import com.google.common.hash.Hashing;
 import org.gradle.api.Project;
-import org.objectweb.asm.commons.Remapper;
 
 import net.fabricmc.accesswidener.AccessWidener;
 import net.fabricmc.accesswidener.AccessWidenerReader;
-import net.fabricmc.accesswidener.AccessWidenerRemapper;
-import net.fabricmc.accesswidener.AccessWidenerWriter;
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
 import net.fabricmc.loom.configuration.processors.JarProcessor;
 import net.fabricmc.loom.util.ZipUtils;
 
@@ -96,25 +92,6 @@ public class AccessWidenerJarProcessor implements JarProcessor {
 		}
 	}
 
-	/**
-	 * Get this mods access widener remapped to the intermediary namespace.
-	 */
-	public byte[] getRemappedAccessWidener(Remapper asmRemapper, String targetNamespace) throws IOException {
-		int version = AccessWidenerReader.readVersion(modAccessWidener);
-
-		AccessWidenerWriter writer = new AccessWidenerWriter(version);
-		AccessWidenerRemapper remapper = new AccessWidenerRemapper(
-				writer,
-				asmRemapper,
-				MappingsNamespace.NAMED.toString(),
-				targetNamespace
-		);
-		AccessWidenerReader reader = new AccessWidenerReader(remapper);
-		reader.read(modAccessWidener);
-
-		return writer.write();
-	}
-
 	@Override
 	public boolean isInvalid(File file) {
 		byte[] hash;

src/main/java/net/fabricmc/loom/configuration/accesswidener/TransitiveAccessWidenerJarProcessor.java

@@ -152,7 +152,7 @@ public class TransitiveAccessWidenerJarProcessor implements JarProcessor {
 		try {
 			AccessWidenerRemapper remappingVisitor = new AccessWidenerRemapper(
 					accessWidener,
-					tinyRemapper.getRemapper(),
+					tinyRemapper.getEnvironment().getRemapper(),
 					MappingsNamespace.INTERMEDIARY.toString(),
 					MappingsNamespace.NAMED.toString()
 			);

src/main/java/net/fabricmc/loom/configuration/ide/RunConfig.java

@@ -24,15 +24,19 @@
 
 package net.fabricmc.loom.configuration.ide;
 
+import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.LinkedList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 import java.util.function.Consumer;
 
 import com.google.common.collect.ImmutableMap;
@@ -48,6 +52,9 @@ import org.w3c.dom.Node;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.configuration.InstallerData;
+import net.fabricmc.loom.configuration.ide.idea.IdeaSyncTask;
+import net.fabricmc.loom.configuration.providers.BundleMetadata;
+import net.fabricmc.loom.util.Constants;
 
 public class RunConfig {
 	public String configName;
@@ -57,6 +64,7 @@ public class RunConfig {
 	public String mainClass;
 	public String runDirIdeaUrl;
 	public String runDir;
+	public String environment;
 	public List<String> vmArgs = new ArrayList<>();
 	public List<String> programArgs = new ArrayList<>();
 	public List<String> vscodeBeforeRun = new ArrayList<>();
@@ -179,6 +187,7 @@ public class RunConfig {
 		runConfig.runDirIdeaUrl = "file://$PROJECT_DIR$/" + runDir;
 		runConfig.runDir = runDir;
 		runConfig.sourceSet = sourceSet;
+		runConfig.environment = environment;
 
 		// Custom parameters
 		runConfig.programArgs.addAll(settings.getProgramArgs());
@@ -195,7 +204,7 @@ public class RunConfig {
 	public String fromDummy(String dummy, boolean relativeDir, Project project) throws IOException {
 		String dummyConfig;
 
-		try (InputStream input = SetupIntelijRunConfigs.class.getClassLoader().getResourceAsStream(dummy)) {
+		try (InputStream input = IdeaSyncTask.class.getClassLoader().getResourceAsStream(dummy)) {
 			dummyConfig = new String(input.readAllBytes(), StandardCharsets.UTF_8);
 		}
 
@@ -249,7 +258,12 @@ public class RunConfig {
 			}
 
 			first = false;
-			sb.append("\"").append(arg).append("\"");
+
+			if (arg.contains(" ")) {
+				sb.append("\"").append(arg).append("\"");
+			} else {
+				sb.append(arg);
+			}
 		}
 
 		return sb.toString();
@@ -285,6 +299,31 @@ public class RunConfig {
 		return defaultMainClass;
 	}
 
+	public List<String> getExcludedLibraryPaths(Project project) {
+		if (!environment.equals("server")) {
+			return Collections.emptyList();
+		}
+
+		final BundleMetadata bundleMetadata = LoomGradleExtension.get(project).getMinecraftProvider().getServerBundleMetadata();
+
+		if (bundleMetadata == null) {
+			// Legacy version
+			return Collections.emptyList();
+		}
+
+		final Set<File> allLibraries = project.getConfigurations().getByName(Constants.Configurations.MINECRAFT_DEPENDENCIES).getFiles();
+		final Set<File> serverLibraries = project.getConfigurations().getByName(Constants.Configurations.MINECRAFT_SERVER_DEPENDENCIES).getFiles();
+		final List<String> clientOnlyLibraries = new LinkedList<>();
+
+		for (File commonLibrary : allLibraries) {
+			if (!serverLibraries.contains(commonLibrary)) {
+				clientOnlyLibraries.add(commonLibrary.getAbsolutePath());
+			}
+		}
+
+		return clientOnlyLibraries;
+	}
+
 	private static String encodeEscaped(String s) {
 		StringBuilder ret = new StringBuilder();
 

src/main/java/net/fabricmc/loom/configuration/ide/RunConfigSettings.java

@@ -35,7 +35,7 @@ import java.util.function.Function;
 
 import org.gradle.api.Named;
 import org.gradle.api.Project;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.JavaPluginExtension;
 import org.gradle.api.tasks.SourceSet;
 import org.jetbrains.annotations.ApiStatus;
 
@@ -247,10 +247,7 @@ public final class RunConfigSettings implements Named {
 	}
 
 	public void source(String source) {
-		setSource(proj -> {
-			JavaPluginConvention conv = proj.getConvention().getPlugin(JavaPluginConvention.class);
-			return conv.getSourceSets().getByName(source);
-		});
+		setSource(proj -> project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets().getByName(source));
 	}
 
 	public void ideConfigGenerated(boolean ideConfigGenerated) {
@@ -261,7 +258,7 @@ public final class RunConfigSettings implements Named {
 	 * Add the {@code -XstartOnFirstThread} JVM argument when on OSX.
 	 */
 	public void startFirstThread() {
-		if (OperatingSystem.getOS().equalsIgnoreCase("osx")) {
+		if (OperatingSystem.CURRENT_OS.equals(OperatingSystem.MAC_OS)) {
 			vmArg("-XstartOnFirstThread");
 		}
 	}

src/main/java/net/fabricmc/loom/configuration/ide/SetupIntelijRunConfigs.java

@@ -1,94 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2016-2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.configuration.ide;
-
-import java.io.File;
-import java.io.IOException;
-import java.nio.charset.StandardCharsets;
-
-import org.apache.commons.io.FileUtils;
-import org.gradle.api.Project;
-
-import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.configuration.providers.minecraft.MinecraftNativesProvider;
-import net.fabricmc.loom.configuration.providers.minecraft.assets.MinecraftAssetsProvider;
-
-public class SetupIntelijRunConfigs {
-	public static void setup(Project project) {
-		File projectDir = project.getRootProject().file(".idea");
-
-		if (!projectDir.exists()) {
-			return;
-		}
-
-		try {
-			generate(project, false);
-		} catch (IOException e) {
-			throw new RuntimeException("Failed to generate run configs", e);
-		}
-	}
-
-	public static void generate(Project project, boolean override) throws IOException {
-		Project rootProject = project.getRootProject();
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-
-		if (extension.ideSync()) {
-			//Ensures the assets are downloaded when idea is syncing a project
-			MinecraftAssetsProvider.provide(extension.getMinecraftProvider(), project);
-			MinecraftNativesProvider.provide(project);
-		}
-
-		String projectPath = project == rootProject ? "" : project.getPath().replace(':', '_');
-
-		File projectDir = rootProject.file(".idea");
-		File runConfigsDir = new File(projectDir, "runConfigurations");
-
-		if (!runConfigsDir.exists()) {
-			runConfigsDir.mkdirs();
-		}
-
-		for (RunConfigSettings settings : extension.getRunConfigs()) {
-			if (!settings.isIdeConfigGenerated()) {
-				continue;
-			}
-
-			RunConfig config = RunConfig.runConfig(project, settings);
-			String name = config.configName.replaceAll("[^a-zA-Z0-9$_]", "_");
-
-			File runConfigs = new File(runConfigsDir, name + projectPath + ".xml");
-			String runConfigXml = config.fromDummy("idea_run_config_template.xml", true, project);
-
-			if (runConfigs.exists() && override) {
-				runConfigs.delete();
-			}
-
-			if (!runConfigs.exists()) {
-				FileUtils.writeStringToFile(runConfigs, runConfigXml, StandardCharsets.UTF_8);
-			}
-
-			settings.makeRunDir();
-		}
-	}
-}

src/main/java/net/fabricmc/loom/configuration/ide/idea/IdeaConfiguration.java

@@ -0,0 +1,47 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.ide.idea;
+
+import java.util.List;
+
+import org.gradle.api.Project;
+import org.gradle.api.tasks.TaskProvider;
+import org.gradle.execution.taskgraph.TaskExecutionGraphInternal;
+
+public class IdeaConfiguration {
+	public static void setup(Project project) {
+		TaskProvider<IdeaSyncTask> ideaSyncTask = project.getTasks().register("ideaSyncTask", IdeaSyncTask.class, ideaSyncTask1 -> {
+			ideaSyncTask1.dependsOn(project.getTasks().named("downloadAssets"));
+		});
+
+		if (!IdeaUtils.isIdeaSync()) {
+			return;
+		}
+
+		// Run the idea sync task, is this exposed via the api?
+		final TaskExecutionGraphInternal taskGraph = (TaskExecutionGraphInternal) project.getGradle().getTaskGraph();
+		taskGraph.whenReady(taskExecutionGraph -> taskGraph.addEntryTasks(List.of(ideaSyncTask.get())));
+	}
+}

src/main/java/net/fabricmc/loom/configuration/ide/idea/IdeaSyncTask.java

@@ -0,0 +1,180 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.ide.idea;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.StringReader;
+import java.io.StringWriter;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+import javax.inject.Inject;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.transform.OutputKeys;
+import javax.xml.transform.Transformer;
+import javax.xml.transform.TransformerFactory;
+import javax.xml.transform.dom.DOMSource;
+import javax.xml.transform.stream.StreamResult;
+
+import org.apache.commons.io.FileUtils;
+import org.gradle.api.Project;
+import org.gradle.api.tasks.TaskAction;
+import org.jetbrains.annotations.VisibleForTesting;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import org.w3c.dom.NodeList;
+import org.xml.sax.InputSource;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.configuration.ide.RunConfig;
+import net.fabricmc.loom.configuration.ide.RunConfigSettings;
+import net.fabricmc.loom.task.AbstractLoomTask;
+
+public abstract class IdeaSyncTask extends AbstractLoomTask {
+	@Inject
+	public IdeaSyncTask() {
+		// Always re-run this task.
+		getOutputs().upToDateWhen(element -> false);
+	}
+
+	@TaskAction
+	public void runTask() throws IOException {
+		File projectDir = getProject().getRootProject().file(".idea");
+
+		if (!projectDir.exists()) {
+			throw new RuntimeException("No .idea directory found");
+		}
+
+		generateRunConfigs();
+	}
+
+	// See: https://github.com/FabricMC/fabric-loom/pull/206#issuecomment-986054254 for the reason why XML's are still used to provide the run configs
+	private void generateRunConfigs() throws IOException {
+		Project rootProject = getProject().getRootProject();
+		LoomGradleExtension extension = LoomGradleExtension.get(getProject());
+		String projectPath = getProject() == rootProject ? "" : getProject().getPath().replace(':', '_');
+		File runConfigsDir = new File(rootProject.file(".idea"), "runConfigurations");
+
+		if (!runConfigsDir.exists()) {
+			runConfigsDir.mkdirs();
+		}
+
+		for (RunConfigSettings settings : extension.getRunConfigs()) {
+			if (!settings.isIdeConfigGenerated()) {
+				continue;
+			}
+
+			RunConfig config = RunConfig.runConfig(getProject(), settings);
+			String name = config.configName.replaceAll("[^a-zA-Z0-9$_]", "_");
+
+			File runConfigs = new File(runConfigsDir, name + projectPath + ".xml");
+			String runConfigXml = config.fromDummy("idea_run_config_template.xml", true, getProject());
+
+			if (!runConfigs.exists()) {
+				FileUtils.writeStringToFile(runConfigs, runConfigXml, StandardCharsets.UTF_8);
+			}
+
+			settings.makeRunDir();
+
+			final List<String> excludedLibraryPaths = config.getExcludedLibraryPaths(getProject());
+
+			if (!excludedLibraryPaths.isEmpty()) {
+				try {
+					setClasspathModifications(runConfigs.toPath(), excludedLibraryPaths);
+				} catch (Exception e) {
+					getProject().getLogger().error("Failed to modify run configuration xml", e);
+				}
+			}
+		}
+	}
+
+	private void setClasspathModifications(Path runConfig, List<String> exclusions) throws IOException {
+		if (!IdeaUtils.supportsCustomizableClasspath()) {
+			return;
+		}
+
+		final String inputXml = Files.readString(runConfig, StandardCharsets.UTF_8);
+		final String outputXml;
+
+		try {
+			outputXml = setClasspathModificationsInXml(inputXml, exclusions);
+		} catch (Exception e) {
+			getLogger().error("Failed to modify idea xml", e);
+
+			return;
+		}
+
+		if (!inputXml.equals(outputXml)) {
+			Files.writeString(runConfig, outputXml, StandardCharsets.UTF_8);
+		}
+	}
+
+	@VisibleForTesting
+	public static String setClasspathModificationsInXml(String input, List<String> exclusions) throws Exception {
+		final DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
+		final DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
+		final Document document = documentBuilder.parse(new InputSource(new StringReader(input)));
+		final Element root = document.getDocumentElement();
+
+		final NodeList nodeList = root.getElementsByTagName("configuration");
+		assert nodeList.getLength() == 1;
+
+		final Element configuration = (Element) nodeList.item(0);
+		final NodeList classpathModificationsList = configuration.getElementsByTagName("classpathModifications");
+
+		// Remove all the existing exclusions
+		for (int i = 0; i < classpathModificationsList.getLength(); i++) {
+			configuration.removeChild(classpathModificationsList.item(i));
+		}
+
+		final Element classpathModifications = document.createElement("classpathModifications");
+
+		for (String exclusionPath : exclusions) {
+			final Element exclusion = document.createElement("entry");
+
+			exclusion.setAttribute("exclude", "true");
+			exclusion.setAttribute("path", exclusionPath);
+
+			classpathModifications.appendChild(exclusion);
+		}
+
+		configuration.appendChild(classpathModifications);
+
+		final TransformerFactory transformerFactory = TransformerFactory.newInstance();
+		final Transformer transformer = transformerFactory.newTransformer();
+		transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
+
+		final DOMSource source = new DOMSource(document);
+
+		final StringWriter writer = new StringWriter();
+		transformer.transform(source, new StreamResult(writer));
+
+		return writer.toString().replace("\r", "");
+	}
+}

src/main/java/net/fabricmc/loom/configuration/ide/idea/IdeaUtils.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2021 FabricMC
+ * Copyright (c) 2021 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -22,26 +22,24 @@
  * SOFTWARE.
  */
 
-package net.fabricmc.loom.build.nesting;
+package net.fabricmc.loom.configuration.ide.idea;
 
-import java.io.File;
-import java.util.Arrays;
-import java.util.Collection;
-import java.util.stream.Collectors;
+import java.util.Objects;
 
-import org.gradle.api.Project;
-
-public record MergedNestedJarProvider(NestedJarProvider... children) implements NestedJarProvider {
-	@Override
-	public Collection<File> provide() {
-		return Arrays.stream(children)
-				.map(NestedJarProvider::provide)
-				.flatMap(Collection::stream)
-				.collect(Collectors.toList());
+public class IdeaUtils {
+	public static boolean isIdeaSync() {
+		return Boolean.parseBoolean(System.getProperty("idea.sync.active", "false"));
 	}
 
-	@Override
-	public void prepare(Project project) {
-		Arrays.stream(children).forEach(nestedJarProvider -> nestedJarProvider.prepare(project));
+	public static String getIdeaVersion() {
+		return Objects.requireNonNull(System.getProperty("idea.version"), "Could not get idea version");
+	}
+
+	// 2021.3 or newer
+	public static boolean supportsCustomizableClasspath() {
+		final String[] split = getIdeaVersion().split("\\.");
+		final int major = Integer.parseInt(split[0]);
+		final int minor = Integer.parseInt(split[1]);
+		return major > 2021 || (major == 2021 && minor >= 3);
 	}
 }

src/main/java/net/fabricmc/loom/configuration/ifaceinject/InterfaceInjectionProcessor.java

@@ -0,0 +1,299 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.ifaceinject;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import com.google.common.hash.Hasher;
+import com.google.common.hash.Hashing;
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import org.gradle.api.Project;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.commons.Remapper;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.configuration.RemappedConfigurationEntry;
+import net.fabricmc.loom.configuration.processors.JarProcessor;
+import net.fabricmc.loom.util.Constants;
+import net.fabricmc.loom.util.Pair;
+import net.fabricmc.loom.util.TinyRemapperHelper;
+import net.fabricmc.loom.util.ZipUtils;
+import net.fabricmc.tinyremapper.TinyRemapper;
+
+public class InterfaceInjectionProcessor implements JarProcessor {
+	// Filename used to store hash of injected interfaces in processed jar file
+	private static final String HASH_FILENAME = "injected_interfaces.sha256";
+
+	private final Map<String, List<InjectedInterface>> injectedInterfaces;
+	private final Project project;
+	private final LoomGradleExtension extension;
+	private final byte[] inputHash;
+	private Map<String, List<InjectedInterface>> remappedInjectedInterfaces;
+
+	public InterfaceInjectionProcessor(Project project) {
+		this.project = project;
+		this.extension = LoomGradleExtension.get(project);
+		this.injectedInterfaces = getInjectedInterfaces().stream()
+				.collect(Collectors.groupingBy(InjectedInterface::className));
+
+		this.inputHash = hashInjectedInterfaces();
+	}
+
+	public boolean isEmpty() {
+		return injectedInterfaces.isEmpty();
+	}
+
+	@Override
+	public void setup() {
+	}
+
+	@Override
+	public void process(File jarFile) {
+		// Lazily remap from intermediary->named
+		if (remappedInjectedInterfaces == null) {
+			TinyRemapper tinyRemapper = createTinyRemapper();
+			Remapper remapper = tinyRemapper.getEnvironment().getRemapper();
+
+			try {
+				remappedInjectedInterfaces = new HashMap<>(injectedInterfaces.size());
+
+				for (Map.Entry<String, List<InjectedInterface>> entry : injectedInterfaces.entrySet()) {
+					String namedClassName = remapper.map(entry.getKey());
+					remappedInjectedInterfaces.put(
+							namedClassName,
+							entry.getValue().stream()
+									.map(injectedInterface ->
+											new InjectedInterface(
+													injectedInterface.modId(),
+													namedClassName,
+													remapper.map(injectedInterface.ifaceName())
+											))
+									.toList()
+					);
+				}
+			} finally {
+				tinyRemapper.finish();
+			}
+		}
+
+		project.getLogger().lifecycle("Processing file: " + jarFile.getName());
+
+		try {
+			ZipUtils.transform(jarFile.toPath(), getTransformers());
+		} catch (IOException e) {
+			throw new RuntimeException("Failed to apply interface injections to " + jarFile, e);
+		}
+	}
+
+	private List<Pair<String, ZipUtils.UnsafeUnaryOperator<byte[]>>> getTransformers() {
+		return remappedInjectedInterfaces.keySet().stream()
+				.map(string -> new Pair<>(string.replaceAll("\\.", "/") + ".class", getTransformer(string)))
+				.collect(Collectors.toList());
+	}
+
+	private ZipUtils.UnsafeUnaryOperator<byte[]> getTransformer(String className) {
+		return input -> {
+			ClassReader reader = new ClassReader(input);
+			ClassWriter writer = new ClassWriter(0);
+			List<InjectedInterface> ifaces = remappedInjectedInterfaces.get(className);
+			ClassVisitor classVisitor = new InjectingClassVisitor(Constants.ASM_VERSION, writer, ifaces);
+
+			// Log which mods add which interface to the class
+			project.getLogger().info("Injecting interfaces into " + className + ": "
+					+ ifaces.stream().map(i -> i.ifaceName() + " [" + i.modId() + "]"
+			).collect(Collectors.joining(", ")));
+
+			reader.accept(classVisitor, 0);
+			return writer.toByteArray();
+		};
+	}
+
+	@Override
+	public boolean isInvalid(File file) {
+		byte[] hash;
+
+		try {
+			hash = ZipUtils.unpackNullable(file.toPath(), HASH_FILENAME);
+		} catch (IOException e) {
+			return true;
+		}
+
+		if (hash == null) {
+			return true;
+		}
+
+		return !Arrays.equals(inputHash, hash);
+	}
+
+	private List<InjectedInterface> getInjectedInterfaces() {
+		List<InjectedInterface> result = new ArrayList<>();
+
+		for (RemappedConfigurationEntry entry : Constants.MOD_COMPILE_ENTRIES) {
+			// Only apply injected interfaces from mods that are part of the compile classpath
+			if (!entry.compileClasspath()) {
+				continue;
+			}
+
+			Set<File> artifacts = extension.getLazyConfigurationProvider(entry.sourceConfiguration())
+					.get()
+					.resolve();
+
+			for (File artifact : artifacts) {
+				result.addAll(InjectedInterface.fromModJar(artifact.toPath()));
+			}
+		}
+
+		return result;
+	}
+
+	private record InjectedInterface(String modId, String className, String ifaceName) {
+		/**
+		 * Reads the injected interfaces contained in a mod jar, or returns null if there is none.
+		 */
+		public static List<InjectedInterface> fromModJar(Path modJarPath) {
+			byte[] modJsonBytes;
+
+			try {
+				modJsonBytes = ZipUtils.unpackNullable(modJarPath, "fabric.mod.json");
+			} catch (IOException e) {
+				throw new RuntimeException("Failed to extract fabric.mod.json from " + modJarPath);
+			}
+
+			if (modJsonBytes == null) {
+				return Collections.emptyList();
+			}
+
+			JsonObject jsonObject = new Gson().fromJson(new String(modJsonBytes, StandardCharsets.UTF_8), JsonObject.class);
+
+			String modId = jsonObject.get("id").getAsString();
+
+			if (!jsonObject.has("custom")) {
+				return Collections.emptyList();
+			}
+
+			JsonObject custom = jsonObject.getAsJsonObject("custom");
+
+			if (!custom.has("loom:injected_interfaces")) {
+				return Collections.emptyList();
+			}
+
+			JsonObject addedIfaces = custom.getAsJsonObject("loom:injected_interfaces");
+
+			List<InjectedInterface> result = new ArrayList<>();
+
+			for (String className : addedIfaces.keySet()) {
+				JsonArray ifaceNames = addedIfaces.getAsJsonArray(className);
+
+				for (JsonElement ifaceName : ifaceNames) {
+					result.add(new InjectedInterface(modId, className, ifaceName.getAsString()));
+				}
+			}
+
+			return result;
+		}
+	}
+
+	private static class InjectingClassVisitor extends ClassVisitor {
+		private final List<InjectedInterface> injectedInterfaces;
+
+		InjectingClassVisitor(int asmVersion, ClassWriter writer, List<InjectedInterface> injectedInterfaces) {
+			super(asmVersion, writer);
+			this.injectedInterfaces = injectedInterfaces;
+		}
+
+		@Override
+		public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+			Set<String> modifiedInterfaces = new LinkedHashSet<>(interfaces.length + injectedInterfaces.size());
+			Collections.addAll(modifiedInterfaces, interfaces);
+
+			for (InjectedInterface injectedInterface : injectedInterfaces) {
+				modifiedInterfaces.add(injectedInterface.ifaceName());
+			}
+
+			// See JVMS: https://docs.oracle.com/javase/specs/jvms/se17/html/jvms-4.html#jvms-ClassSignature
+			if (signature != null) {
+				var resultingSignature = new StringBuilder(signature);
+
+				for (InjectedInterface injectedInterface : injectedInterfaces) {
+					String superinterfaceSignature = "L" + injectedInterface.ifaceName() + ";";
+
+					if (resultingSignature.indexOf(superinterfaceSignature) == -1) {
+						resultingSignature.append(superinterfaceSignature);
+					}
+				}
+
+				signature = resultingSignature.toString();
+			}
+
+			super.visit(version, access, name, signature, superName, modifiedInterfaces.toArray(new String[0]));
+		}
+	}
+
+	private TinyRemapper createTinyRemapper() {
+		try {
+			TinyRemapper tinyRemapper = TinyRemapperHelper.getTinyRemapper(project, "intermediary", "named");
+			tinyRemapper.readClassPath(TinyRemapperHelper.getMinecraftDependencies(project));
+			tinyRemapper.readClassPath(extension.getMinecraftMappedProvider().getIntermediaryJar().toPath());
+
+			return tinyRemapper;
+		} catch (IOException e) {
+			throw new RuntimeException("Failed to create tiny remapper for intermediary->named", e);
+		}
+	}
+
+	private byte[] hashInjectedInterfaces() {
+		// Hash the interfaces we're about to inject to not have to repeat this everytime
+		Hasher hasher = Hashing.sha256().newHasher();
+
+		for (Map.Entry<String, List<InjectedInterface>> entry : injectedInterfaces.entrySet()) {
+			hasher.putString("class:", StandardCharsets.UTF_8);
+			hasher.putString(entry.getKey(), StandardCharsets.UTF_8);
+
+			for (InjectedInterface ifaceName : entry.getValue()) {
+				hasher.putString("iface:", StandardCharsets.UTF_8);
+				hasher.putString(ifaceName.ifaceName(), StandardCharsets.UTF_8);
+			}
+		}
+
+		return hasher.hash().asBytes();
+	}
+}

src/main/java/net/fabricmc/loom/configuration/mods/ModVersionParser.java

@@ -30,7 +30,7 @@ import java.io.IOException;
 
 import com.google.gson.JsonObject;
 import org.gradle.api.Project;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.JavaPluginExtension;
 
 import net.fabricmc.loom.LoomGradlePlugin;
 
@@ -67,7 +67,7 @@ public class ModVersionParser {
 	}
 
 	private File locateModJsonFile() {
-		return project.getConvention().getPlugin(JavaPluginConvention.class).getSourceSets()
+		return project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets()
 				.getByName("main")
 				.getResources()
 				.matching(patternFilterable -> patternFilterable.include("fabric.mod.json"))

src/main/java/net/fabricmc/loom/configuration/providers/BundleMetadata.java

@@ -0,0 +1,93 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.providers;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.jetbrains.annotations.Nullable;
+
+import net.fabricmc.loom.util.FileSystemUtil;
+
+public record BundleMetadata(List<Entry> libraries, List<Entry> versions, String mainClass) {
+	private static final String LIBRARIES_LIST_PATH = "META-INF/libraries.list";
+	private static final String VERSIONS_LIST_PATH = "META-INF/versions.list";
+	private static final String MAINCLASS_PATH = "META-INF/main-class";
+
+	@Nullable
+	public static BundleMetadata fromJar(Path jar) throws IOException {
+		final List<Entry> libraries;
+		final List<Entry> versions;
+		final String mainClass;
+
+		try (FileSystemUtil.Delegate fs = FileSystemUtil.getJarFileSystem(jar)) {
+			if (!Files.exists(fs.get().getPath(VERSIONS_LIST_PATH))) {
+				// Legacy jar
+				return null;
+			}
+
+			libraries = readEntries(fs.readString(LIBRARIES_LIST_PATH), "META-INF/libraries/");
+			versions = readEntries(fs.readString(VERSIONS_LIST_PATH), "META-INF/versions/");
+			mainClass = fs.readString(MAINCLASS_PATH).trim();
+		}
+
+		return new BundleMetadata(libraries, versions, mainClass);
+	}
+
+	private static List<Entry> readEntries(String content, String pathPrefix) {
+		List<Entry> entries = new ArrayList<>();
+
+		for (String entry : content.split("\n")) {
+			if (entry.isBlank()) {
+				continue;
+			}
+
+			String[] split = entry.split("\t");
+
+			if (split.length != 3) {
+				continue;
+			}
+
+			entries.add(new Entry(split[0], split[1], pathPrefix + split[2]));
+		}
+
+		return Collections.unmodifiableList(entries);
+	}
+
+	public record Entry(String sha1, String name, String path) {
+		public void unpackEntry(Path jar, Path dest) throws IOException {
+			try (FileSystemUtil.Delegate fs = FileSystemUtil.getJarFileSystem(jar);
+					InputStream is = Files.newInputStream(fs.get().getPath(path()))) {
+				Files.copy(is, dest, StandardCopyOption.REPLACE_EXISTING);
+			}
+		}
+	}
+}

src/main/java/net/fabricmc/loom/configuration/providers/LaunchProvider.java

@@ -57,14 +57,16 @@ public class LaunchProvider extends DependencyProvider {
 
 	@Override
 	public void provide(DependencyInfo dependency, Consumer<Runnable> postPopulationScheduler) throws IOException {
+		final String nativesPath = getExtension().getFiles().getNativesDirectory(getProject()).getAbsolutePath();
+
 		final LaunchConfig launchConfig = new LaunchConfig()
 				.property("fabric.development", "true")
 				.property("fabric.remapClasspathFile", getRemapClasspathFile().getAbsolutePath())
 				.property("log4j.configurationFile", getAllLog4JConfigFiles())
 				.property("log4j2.formatMsgNoLookups", "true")
 
-				.property("client", "java.library.path", getExtension().getMinecraftProvider().nativesDir().getAbsolutePath())
-				.property("client", "org.lwjgl.librarypath", getExtension().getMinecraftProvider().nativesDir().getAbsolutePath());
+				.property("client", "java.library.path", nativesPath)
+				.property("client", "org.lwjgl.librarypath", nativesPath);
 
 		if (!getExtension().isForge()) {
 			launchConfig

src/main/java/net/fabricmc/loom/configuration/providers/MinecraftProvider.java

@@ -31,10 +31,6 @@ import net.fabricmc.loom.configuration.providers.minecraft.MinecraftVersionMeta;
 public interface MinecraftProvider {
 	File workingDir();
 
-	boolean hasCustomNatives();
-
-	File nativesDir();
-
 	File dir(String path);
 
 	File file(String path);

src/main/java/net/fabricmc/loom/configuration/providers/MinecraftProviderImpl.java

@@ -27,21 +27,17 @@ package net.fabricmc.loom.configuration.providers;
 import java.io.File;
 import java.io.FileReader;
 import java.io.IOException;
-import java.io.InputStream;
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
-import java.nio.file.StandardCopyOption;
-import java.util.Objects;
 import java.util.Optional;
 import java.util.function.Consumer;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipFile;
 
 import com.google.common.base.Stopwatch;
 import com.google.common.io.Files;
 import org.gradle.api.GradleException;
 import org.gradle.api.Project;
 import org.gradle.api.logging.Logger;
+import org.jetbrains.annotations.Nullable;
 
 import net.fabricmc.loom.LoomGradlePlugin;
 import net.fabricmc.loom.configuration.DependencyProvider;
@@ -49,10 +45,9 @@ import net.fabricmc.loom.configuration.providers.minecraft.ManifestVersion;
 import net.fabricmc.loom.configuration.providers.minecraft.MinecraftLibraryProvider;
 import net.fabricmc.loom.configuration.providers.minecraft.MinecraftVersionMeta;
 import net.fabricmc.loom.util.Constants;
-import net.fabricmc.loom.util.MirrorUtil;
 import net.fabricmc.loom.util.DownloadUtil;
 import net.fabricmc.loom.util.HashedDownloadUtil;
-import net.fabricmc.loom.util.ZipUtils;
+import net.fabricmc.loom.util.MirrorUtil;
 import net.fabricmc.stitch.merge.JarMerger;
 
 public class MinecraftProviderImpl extends DependencyProvider implements MinecraftProvider {
@@ -68,6 +63,8 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 	public File minecraftServerJar;
 	// The extracted server jar from the boostrap, only exists in >=21w39a
 	public File minecraftExtractedServerJar;
+	@Nullable
+	private BundleMetadata serverBundleMetadata;
 	private Boolean isNewerThan21w39a;
 	private File minecraftMergedJar;
 	private File versionManifestJson;
@@ -109,6 +106,8 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 			downloadJars(getProject().getLogger());
 		}
 
+		serverBundleMetadata = BundleMetadata.fromJar(minecraftServerJar.toPath());
+
 		libraryProvider = new MinecraftLibraryProvider();
 		libraryProvider.provide(this, getProject());
 
@@ -274,7 +273,20 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 		logger.info(":merging jars");
 		Stopwatch stopwatch = Stopwatch.createStarted();
 
-		try (JarMerger jarMerger = new JarMerger(minecraftClientJar, getServerJarToMerge(logger), minecraftMergedJar)) {
+		File jarToMerge = minecraftServerJar;
+
+		if (serverBundleMetadata != null) {
+			logger.info(":Extracting server jar from bootstrap");
+
+			if (serverBundleMetadata.versions().size() != 1) {
+				throw new UnsupportedOperationException("Expected only 1 version in META-INF/versions.list, but got %d".formatted(serverBundleMetadata.versions().size()));
+			}
+
+			serverBundleMetadata.versions().get(0).unpackEntry(minecraftServerJar.toPath(), minecraftExtractedServerJar.toPath());
+			jarToMerge = minecraftExtractedServerJar;
+		}
+
+		try (JarMerger jarMerger = new JarMerger(minecraftClientJar, jarToMerge, minecraftMergedJar)) {
 			jarMerger.enableSyntheticParamsOffset();
 			jarMerger.merge();
 		}
@@ -282,78 +294,6 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 		logger.info(":merged jars in " + stopwatch);
 	}
 
-	private File getServerJarToMerge(Logger logger) throws IOException {
-		try (ZipFile zipFile = new ZipFile(minecraftServerJar)) {
-			ZipEntry versionsListEntry = zipFile.getEntry("META-INF/versions.list");
-
-			if (versionsListEntry == null) {
-				// Legacy pre 21w38a jar
-				return minecraftServerJar;
-			}
-
-			logger.info(":Extracting server jar from bootstrap");
-
-			String versionsList;
-
-			try (InputStream is = zipFile.getInputStream(versionsListEntry)) {
-				versionsList = new String(is.readAllBytes(), StandardCharsets.UTF_8);
-			}
-
-			String jarPath = null;
-			String[] versions = versionsList.split("\n");
-
-			if (versions.length != 1) {
-				throw new UnsupportedOperationException("Expected only 1 version in META-INF/versions.list, but got %d".formatted(versions.length));
-			}
-
-			for (String version : versions) {
-				if (version.isBlank()) continue;
-
-				String[] split = version.split("\t");
-
-				if (split.length != 3) continue;
-
-				final String hash = split[0];
-				final String id = split[1];
-				final String path = split[2];
-
-				// Take the first (only) version we find.
-				jarPath = path;
-				break;
-			}
-
-			Objects.requireNonNull(jarPath, "Could not find minecraft server jar for " + minecraftVersion());
-			ZipEntry serverJarEntry = zipFile.getEntry("META-INF/versions/" + jarPath);
-			Objects.requireNonNull(serverJarEntry, "Could not find server jar in boostrap@ " + jarPath);
-
-			try (InputStream is = zipFile.getInputStream(serverJarEntry)) {
-				java.nio.file.Files.copy(is, minecraftExtractedServerJar.toPath(), StandardCopyOption.REPLACE_EXISTING);
-			}
-
-			return minecraftExtractedServerJar;
-		}
-	}
-
-	public File getMinecraftServerJar() {
-		if (isNewerThan21w39a()) {
-			try {
-				return getServerJarToMerge(getProject().getLogger());
-			} catch (IOException e) {
-				throw new RuntimeException(e);
-			}
-		}
-
-		return minecraftServerJar;
-	}
-
-	public boolean isNewerThan21w39a() {
-		if (isNewerThan21w39a != null) {
-			return isNewerThan21w39a;
-		}
-
-		return isNewerThan21w39a = ZipUtils.contains(minecraftServerJar.toPath(), "META-INF/versions.list");
-	}
-
 	public File getMergedJar() {
 		return minecraftMergedJar;
 	}
@@ -363,20 +303,6 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 		return workingDir;
 	}
 
-	@Override
-	public boolean hasCustomNatives() {
-		return getProject().getProperties().get("fabric.loom.natives.dir") != null;
-	}
-
-	@Override
-	public File nativesDir() {
-		if (hasCustomNatives()) {
-			return new File((String) getProject().property("fabric.loom.natives.dir"));
-		}
-
-		return dir("natives");
-	}
-
 	@Override
 	public File dir(String path) {
 		File dir = file(path);
@@ -415,4 +341,9 @@ public class MinecraftProviderImpl extends DependencyProvider implements Minecra
 	public String getTargetConfig() {
 		return Constants.Configurations.MINECRAFT;
 	}
+
+	@Nullable
+	public BundleMetadata getServerBundleMetadata() {
+		return serverBundleMetadata;
+	}
 }

src/main/java/net/fabricmc/loom/configuration/providers/mappings/MappingsProviderImpl.java

@@ -61,6 +61,7 @@ import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
 import net.fabricmc.loom.configuration.DependencyProvider;
 import net.fabricmc.loom.configuration.accesswidener.AccessWidenerJarProcessor;
 import net.fabricmc.loom.configuration.accesswidener.TransitiveAccessWidenerJarProcessor;
+import net.fabricmc.loom.configuration.ifaceinject.InterfaceInjectionProcessor;
 import net.fabricmc.loom.configuration.processors.JarProcessorManager;
 import net.fabricmc.loom.configuration.processors.MinecraftProcessedProvider;
 import net.fabricmc.loom.configuration.providers.MinecraftProviderImpl;
@@ -212,6 +213,14 @@ public class MappingsProviderImpl extends DependencyProvider implements Mappings
 			}
 		}
 
+		if (extension.getEnableInterfaceInjection().get()) {
+			InterfaceInjectionProcessor jarProcessor = new InterfaceInjectionProcessor(getProject());
+
+			if (!jarProcessor.isEmpty()) {
+				extension.getGameJarProcessors().add(jarProcessor);
+			}
+		}
+
 		extension.getAccessWidenerPath().finalizeValue();
 		extension.getGameJarProcessors().finalizeValue();
 		JarProcessorManager processorManager = new JarProcessorManager(extension.getGameJarProcessors().get());
@@ -275,7 +284,7 @@ public class MappingsProviderImpl extends DependencyProvider implements Mappings
 			String yarnMinecraftVersion = yarnVersion.substring(0, yarnVersion.lastIndexOf(separator));
 
 			if (!yarnMinecraftVersion.equalsIgnoreCase(minecraftVersion)) {
-				throw new RuntimeException(String.format("Minecraft Version (%s) does not match yarn's minecraft version (%s)", minecraftVersion, yarnMinecraftVersion));
+				getProject().getLogger().warn("Minecraft Version ({}) does not match yarn's minecraft version ({})", minecraftVersion, yarnMinecraftVersion);
 			}
 
 			// We can save reading the zip file + header by checking the file name
@@ -625,6 +634,10 @@ public class MappingsProviderImpl extends DependencyProvider implements Mappings
 		}
 	}
 
+	public String getBuildServiceName(String name, String from, String to) {
+		return "%s:%s:%s>%S".formatted(name, mappingsIdentifier(), from, to);
+	}
+
 	public record UnpickMetadata(String unpickGroup, String unpickVersion) {
 	}
 }

src/main/java/net/fabricmc/loom/configuration/providers/minecraft/LWJGLVersionOverride.java

@@ -0,0 +1,108 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.providers.minecraft;
+
+import static net.fabricmc.loom.util.OperatingSystem.LINUX;
+import static net.fabricmc.loom.util.OperatingSystem.MAC_OS;
+import static net.fabricmc.loom.util.OperatingSystem.WINDOWS;
+
+import java.util.List;
+
+import org.gradle.api.Project;
+import org.jetbrains.annotations.Nullable;
+
+import net.fabricmc.loom.util.Architecture;
+import net.fabricmc.loom.util.OperatingSystem;
+
+public class LWJGLVersionOverride {
+	public static final String LWJGL_VERSION = "3.3.0";
+	@Nullable
+	public static final String NATIVE_CLASSIFIER = getNativesClassifier();
+
+	public static final List<String> DEPENDENCIES = List.of(
+			"org.lwjgl:lwjgl:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-glfw:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-jemalloc:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-openal:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-opengl:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-stb:" + LWJGL_VERSION,
+			"org.lwjgl:lwjgl-tinyfd:" + LWJGL_VERSION
+	);
+	public static final List<String> NATIVES = DEPENDENCIES.stream().map(s -> s + ":" + NATIVE_CLASSIFIER).toList();
+
+	/**
+	 * Update lwjgl by default when running on arm and a supported configuration.
+	 */
+	public static boolean overrideByDefault() {
+		return NATIVE_CLASSIFIER != null && Architecture.CURRENT.isArm();
+	}
+
+	public static boolean forceOverride(Project project) {
+		return project.getProperties().get("fabric.loom.override-lwjgl") != null;
+	}
+
+	@Nullable
+	private static String getNativesClassifier() {
+		return switch (OperatingSystem.CURRENT_OS) {
+		case WINDOWS -> getWindowsClassifier();
+		case MAC_OS -> getMacOSClassifier();
+		case LINUX -> getLinuxClassifier();
+		default -> null;
+		};
+	}
+
+	private static String getWindowsClassifier() {
+		if (Architecture.CURRENT.is64Bit()) {
+			if (Architecture.CURRENT.isArm()) {
+				// Arm 64 bit
+				return "natives-windows-arm64";
+			}
+
+			// None arm 64bit
+			return "natives-windows";
+		}
+
+		// All 32bit, including arm
+		return "natives-windows-x86";
+	}
+
+	private static String getMacOSClassifier() {
+		if (Architecture.CURRENT.isArm()) {
+			// Apple silicone arm
+			return "natives-macos-arm64";
+		}
+
+		// Intel 64bit.
+		return "natives-macos";
+	}
+
+	private static String getLinuxClassifier() {
+		if (Architecture.CURRENT.isArm()) {
+			return Architecture.CURRENT.is64Bit() ? "natives-linux-arm64" : "natives-linux-arm32";
+		}
+
+		return "natives-linux";
+	}
+}

src/main/java/net/fabricmc/loom/configuration/providers/minecraft/MinecraftLibraryProvider.java

@@ -24,31 +24,77 @@
 
 package net.fabricmc.loom.configuration.providers.minecraft;
 
-import java.io.File;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.gradle.api.Project;
+import org.gradle.api.artifacts.ExternalModuleDependency;
 
-import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.configuration.providers.BundleMetadata;
 import net.fabricmc.loom.configuration.providers.MinecraftProviderImpl;
 import net.fabricmc.loom.util.Constants;
 
 public class MinecraftLibraryProvider {
-	public File MINECRAFT_LIBS;
+	private static final Pattern NATIVES_PATTERN = Pattern.compile("^(?<group>.*)/(.*?)/(?<version>.*)/((?<name>.*?)-([0-9].*?)-)(?<classifier>.*).jar$");
 
 	public void provide(MinecraftProviderImpl minecraftProvider, Project project) {
 		MinecraftVersionMeta versionInfo = minecraftProvider.getVersionInfo();
+		BundleMetadata serverBundleMetadata = minecraftProvider.getServerBundleMetadata();
 
-		initFiles(project, minecraftProvider);
+		final boolean overrideLWJGL = LWJGLVersionOverride.overrideByDefault() || LWJGLVersionOverride.forceOverride(project) || Boolean.getBoolean("loom.test.lwjgloverride");
+
+		if (overrideLWJGL) {
+			project.getLogger().warn("Loom is upgrading Minecraft's LWJGL version to {}", LWJGLVersionOverride.LWJGL_VERSION);
+		}
 
 		for (MinecraftVersionMeta.Library library : versionInfo.libraries()) {
-			if (library.isValidForOS() && !library.hasNatives() && library.artifact() != null) {
-				project.getDependencies().add(Constants.Configurations.MINECRAFT_DEPENDENCIES, project.getDependencies().module(library.name()));
+			if (overrideLWJGL && library.name().startsWith("org.lwjgl")) {
+				continue;
 			}
+
+			if (library.isValidForOS() && !library.hasNatives() && library.artifact() != null) {
+				if (serverBundleMetadata != null && isLibraryInBundle(serverBundleMetadata, library)) {
+					project.getDependencies().add(Constants.Configurations.MINECRAFT_SERVER_DEPENDENCIES, library.name());
+				} else {
+					// Client only library, or legacy version
+					project.getDependencies().add(Constants.Configurations.MINECRAFT_DEPENDENCIES, library.name());
+				}
+			}
+
+			if (library.hasNativesForOS()) {
+				MinecraftVersionMeta.Download nativeDownload = library.classifierForOS();
+
+				Matcher matcher = NATIVES_PATTERN.matcher(nativeDownload.path());
+
+				if (!matcher.find()) {
+					project.getLogger().warn("Failed to match regex for natives path : " + nativeDownload.path());
+					continue;
+				}
+
+				final String group = matcher.group("group").replace("/", ".");
+				final String name = matcher.group("name");
+				final String version = matcher.group("version");
+				final String classifier = matcher.group("classifier");
+
+				final String dependencyNotation = "%s:%s:%s:%s".formatted(group, name, version, classifier);
+
+				project.getLogger().debug("Add native dependency '{}'", dependencyNotation);
+				project.getDependencies().add(Constants.Configurations.MINECRAFT_NATIVES, dependencyNotation);
+			}
+		}
+
+		if (overrideLWJGL) {
+			LWJGLVersionOverride.DEPENDENCIES.forEach(s -> project.getDependencies().add(Constants.Configurations.MINECRAFT_DEPENDENCIES, s));
+			LWJGLVersionOverride.NATIVES.forEach(s -> project.getDependencies().add(Constants.Configurations.MINECRAFT_NATIVES, s));
+
+			// Add the native support mod that fixes a handful of issues related to the LWJGL update at runtime.
+			ExternalModuleDependency dependency = (ExternalModuleDependency) project.getDependencies().create(Constants.Dependencies.NATIVE_SUPPORT + Constants.Dependencies.Versions.NATIVE_SUPPORT_VERSION);
+			dependency.setTransitive(false);
+			project.getDependencies().add("modLocalRuntime", dependency);
 		}
 	}
 
-	private void initFiles(Project project, MinecraftProviderImpl minecraftProvider) {
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-		MINECRAFT_LIBS = new File(extension.getFiles().getUserCache(), "libraries");
+	private static boolean isLibraryInBundle(BundleMetadata bundleMetadata, MinecraftVersionMeta.Library library) {
+		return bundleMetadata.libraries().stream().anyMatch(entry -> entry.name().equals(library.name()));
 	}
 }

src/main/java/net/fabricmc/loom/configuration/providers/minecraft/MinecraftNativesProvider.java

@@ -1,150 +0,0 @@
-/*
- * This file is part of fabric-loom, licensed under the MIT License (MIT).
- *
- * Copyright (c) 2016-2021 FabricMC
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package net.fabricmc.loom.configuration.providers.minecraft;
-
-import java.io.File;
-import java.io.IOException;
-import java.net.URL;
-import java.nio.charset.StandardCharsets;
-import java.util.List;
-import java.util.Objects;
-import java.util.stream.Collectors;
-
-import org.apache.commons.io.FileUtils;
-import org.gradle.api.GradleException;
-import org.gradle.api.Project;
-
-import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.LoomGradlePlugin;
-import net.fabricmc.loom.util.HashedDownloadUtil;
-import net.fabricmc.loom.util.MirrorUtil;
-import net.fabricmc.loom.util.ZipUtils;
-
-public class MinecraftNativesProvider {
-	private final Project project;
-	private final LoomGradleExtension extension;
-	private final File nativesDir;
-	private final File jarStore;
-
-	public MinecraftNativesProvider(Project project) {
-		this.project = project;
-		extension = LoomGradleExtension.get(project);
-
-		nativesDir = extension.getMinecraftProvider().nativesDir();
-		jarStore = extension.getFiles().getNativesJarStore();
-	}
-
-	public static void provide(Project project) throws IOException {
-		new MinecraftNativesProvider(project).provide();
-	}
-
-	private void provide() throws IOException {
-		if (extension.getMinecraftProvider().hasCustomNatives()) {
-			if (!nativesDir.exists()) {
-				throw new RuntimeException("Could no find custom natives directory at " + nativesDir.getAbsolutePath());
-			}
-
-			return;
-		}
-
-		if (!LoomGradlePlugin.refreshDeps && !requiresExtract()) {
-			project.getLogger().info("Natives do no need extracting, skipping");
-			return;
-		}
-
-		extractNatives();
-	}
-
-	private void extractNatives() throws IOException {
-		boolean offline = project.getGradle().getStartParameter().isOffline();
-
-		if (nativesDir.exists()) {
-			try {
-				FileUtils.deleteDirectory(nativesDir);
-			} catch (IOException e) {
-				throw new IOException("Failed to delete the natives directory, is the game running?", e);
-			}
-		}
-
-		nativesDir.mkdirs();
-
-		for (MinecraftVersionMeta.Download library : getNatives()) {
-			File libJarFile = library.relativeFile(jarStore);
-
-			if (!offline) {
-				HashedDownloadUtil.downloadIfInvalid(new URL(MirrorUtil.getLibrariesBase(project) + library.path()), libJarFile, library.sha1(), project.getLogger(), false);
-			}
-
-			if (!libJarFile.exists()) {
-				throw new GradleException("Native jar not found at " + libJarFile.getAbsolutePath());
-			}
-
-			ZipUtils.unpackAll(libJarFile.toPath(), nativesDir.toPath());
-
-			// Store a file containing the hash of the extracted natives, used on subsequent runs to skip extracting all the natives if they haven't changed
-			File libSha1File = new File(nativesDir, libJarFile.getName() + ".sha1");
-			FileUtils.writeStringToFile(libSha1File, library.sha1(), StandardCharsets.UTF_8);
-		}
-	}
-
-	private boolean requiresExtract() {
-		List<MinecraftVersionMeta.Download> natives = getNatives();
-
-		if (natives.isEmpty()) {
-			throw new IllegalStateException("No natives found for the current system");
-		}
-
-		for (MinecraftVersionMeta.Download library : natives) {
-			File libJarFile = library.relativeFile(jarStore);
-			File libSha1File = new File(nativesDir, libJarFile.getName() + ".sha1");
-
-			if (!libSha1File.exists()) {
-				return true;
-			}
-
-			try {
-				String sha1 = FileUtils.readFileToString(libSha1File, StandardCharsets.UTF_8);
-
-				if (!sha1.equalsIgnoreCase(library.sha1())) {
-					return true;
-				}
-			} catch (IOException e) {
-				project.getLogger().error("Failed to read " + libSha1File.getAbsolutePath(), e);
-				return true;
-			}
-		}
-
-		// All looks good, no need to re-extract
-		return false;
-	}
-
-	private List<MinecraftVersionMeta.Download> getNatives() {
-		return extension.getMinecraftProvider().getVersionInfo().libraries().stream()
-				.filter((MinecraftVersionMeta.Library::hasNativesForOS))
-				.map(MinecraftVersionMeta.Library::classifierForOS)
-				.filter(Objects::nonNull)
-				.collect(Collectors.toList());
-	}
-}

src/main/java/net/fabricmc/loom/configuration/providers/minecraft/MinecraftVersionMeta.java

@@ -81,7 +81,7 @@ public record MinecraftVersionMeta(
 				return false;
 			}
 
-			if (natives.get(OperatingSystem.getOS()) == null) {
+			if (natives.get(OperatingSystem.CURRENT_OS) == null) {
 				return false;
 			}
 
@@ -89,7 +89,7 @@ public record MinecraftVersionMeta(
 		}
 
 		public Download classifierForOS() {
-			return downloads().classifier(natives.get(OperatingSystem.getOS()));
+			return downloads().classifier(natives.get(OperatingSystem.CURRENT_OS));
 		}
 
 		public Download artifact() {
@@ -119,7 +119,7 @@ public record MinecraftVersionMeta(
 
 	public record OS(String name) {
 		public boolean isValidForOS() {
-			return name() == null || name().equalsIgnoreCase(OperatingSystem.getOS());
+			return name() == null || name().equalsIgnoreCase(OperatingSystem.CURRENT_OS);
 		}
 	}
 

src/main/java/net/fabricmc/loom/configuration/providers/minecraft/SignatureFixerApplyVisitor.java

@@ -0,0 +1,85 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.configuration.providers.minecraft;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.gradle.api.Project;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.commons.Remapper;
+
+import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
+import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
+import net.fabricmc.loom.util.Constants;
+import net.fabricmc.loom.util.TinyRemapperHelper;
+import net.fabricmc.tinyremapper.TinyRemapper;
+import net.fabricmc.tinyremapper.api.TrClass;
+
+public record SignatureFixerApplyVisitor(Map<String, String> signatureFixes) implements TinyRemapper.ApplyVisitorProvider {
+	@Override
+	public ClassVisitor insertApplyVisitor(TrClass cls, ClassVisitor next) {
+		return new ClassVisitor(Constants.ASM_VERSION, next) {
+			@Override
+			public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
+				if (signature == null) {
+					signature = signatureFixes.getOrDefault(name, null);
+				}
+
+				super.visit(version, access, name, signature, superName, interfaces);
+			}
+		};
+	}
+
+	public static Map<String, String> getRemappedSignatures(boolean toIntermediary, MappingsProviderImpl mappingsProvider, Project project, String targetNamespace) throws IOException {
+		if (mappingsProvider.getSignatureFixes() == null) {
+			// No fixes
+			return Collections.emptyMap();
+		}
+
+		if (toIntermediary) {
+			// No need to remap, as these are already intermediary
+			return mappingsProvider.getSignatureFixes();
+		}
+
+		// Remap the sig fixes from intermediary to the target namespace
+		final Map<String, String> remapped = new HashMap<>();
+		final TinyRemapper sigTinyRemapper = TinyRemapperHelper.getTinyRemapper(project, MappingsNamespace.INTERMEDIARY.toString(), targetNamespace);
+		final Remapper sigAsmRemapper = sigTinyRemapper.getEnvironment().getRemapper();
+
+		// Remap the class names and the signatures using a new tiny remapper instance.
+		for (Map.Entry<String, String> entry : mappingsProvider.getSignatureFixes().entrySet()) {
+			remapped.put(
+					sigAsmRemapper.map(entry.getKey()),
+					sigAsmRemapper.mapSignature(entry.getValue(), false)
+			);
+		}
+
+		sigTinyRemapper.finish();
+		return remapped;
+	}
+}

src/main/java/net/fabricmc/loom/extension/LoomFiles.java

@@ -43,7 +43,7 @@ public interface LoomFiles {
 	File getProjectPersistentCache();
 	File getProjectBuildCache();
 	File getRemappedModCache();
-	File getNativesJarStore();
+	File getNativesDirectory(Project project);
 	File getDefaultLog4jConfigFile();
 	File getDevLauncherConfig();
 	File getUnpickLoggingConfigFile();

src/main/java/net/fabricmc/loom/extension/LoomFilesBaseImpl.java

@@ -26,6 +26,10 @@ package net.fabricmc.loom.extension;
 
 import java.io.File;
 
+import org.gradle.api.Project;
+
+import net.fabricmc.loom.LoomGradleExtension;
+
 public abstract class LoomFilesBaseImpl implements LoomFiles {
 	protected abstract File getGradleUserHomeDir();
 	protected abstract File getRootDir();
@@ -70,8 +74,8 @@ public abstract class LoomFilesBaseImpl implements LoomFiles {
 	}
 
 	@Override
-	public File getNativesJarStore() {
-		return createFile(getUserCache(), "natives/jars");
+	public File getNativesDirectory(Project project) {
+		return createFile(getRootProjectPersistentCache(), "natives/" + LoomGradleExtension.get(project).getMinecraftProvider().minecraftVersion());
 	}
 
 	@Override

src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionApiImpl.java

@@ -33,6 +33,7 @@ import java.util.function.Consumer;
 
 import com.google.common.base.Suppliers;
 import org.gradle.api.Action;
+import org.gradle.api.DomainObjectCollection;
 import org.gradle.api.NamedDomainObjectContainer;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Dependency;
@@ -69,7 +70,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 	private static final String PLATFORM_PROPERTY = "loom.platform";
 
 	protected final DeprecationHelper deprecationHelper;
-	protected final ListProperty<LoomDecompiler> decompilers;
+	protected final DomainObjectCollection<LoomDecompiler> decompilers;
 	protected final ListProperty<JarProcessor> jarProcessors;
 	protected final ConfigurableFileCollection log4jConfigs;
 	protected final RegularFileProperty accessWidener;
@@ -79,6 +80,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 	protected final Property<Boolean> setupRemappedVariants;
 	protected final Property<Boolean> transitiveAccessWideners;
 	protected final Property<String> intermediary;
+	protected final Property<Boolean> enableInterfaceInjection;
 
 	private final ModVersionParser versionParser;
 
@@ -98,8 +100,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 	protected LoomGradleExtensionApiImpl(Project project, LoomFiles directories) {
 		this.runConfigs = project.container(RunConfigSettings.class,
 				baseName -> new RunConfigSettings(project, baseName));
-		this.decompilers = project.getObjects().listProperty(LoomDecompiler.class)
-				.empty();
+		this.decompilers = project.getObjects().domainObjectSet(LoomDecompiler.class);
 		this.jarProcessors = project.getObjects().listProperty(JarProcessor.class)
 				.empty();
 		this.log4jConfigs = project.files(directories.getDefaultLog4jConfigFile());
@@ -116,6 +117,9 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 		this.transitiveAccessWideners.finalizeValueOnRead();
 		this.intermediary = project.getObjects().property(String.class)
 				.convention("https://maven.fabricmc.net/net/fabricmc/intermediary/%1$s/intermediary-%1$s-v2.jar");
+		this.enableInterfaceInjection = project.getObjects().property(Boolean.class)
+				.convention(true);
+		this.enableInterfaceInjection.finalizeValueOnRead();
 
 		this.versionParser = new ModVersionParser(project);
 
@@ -158,7 +162,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 	}
 
 	@Override
-	public ListProperty<LoomDecompiler> getGameDecompilers() {
+	public DomainObjectCollection<LoomDecompiler> getGameDecompilers() {
 		return decompilers;
 	}
 
@@ -231,6 +235,11 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 		return intermediary;
 	}
 
+	@Override
+	public Property<Boolean> getEnableInterfaceInjection() {
+		return enableInterfaceInjection;
+	}
+
 	@Override
 	public void disableDeprecatedPomGeneration(MavenPublication publication) {
 		net.fabricmc.loom.configuration.MavenPublication.excludePublication(publication);

src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionImpl.java

@@ -26,22 +26,22 @@ package net.fabricmc.loom.extension;
 
 import java.io.File;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 import java.util.function.Supplier;
 
 import com.google.common.base.Suppliers;
 import org.cadixdev.lorenz.MappingSet;
 import org.cadixdev.mercury.Mercury;
+import org.gradle.api.Action;
 import org.gradle.api.NamedDomainObjectProvider;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.file.FileCollection;
+import org.gradle.api.tasks.SourceSet;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.api.ForgeExtensionAPI;
@@ -59,7 +59,7 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 	private final ConfigurableFileCollection unmappedMods;
 	private final Supplier<ForgeExtensionAPI> forgeExtension;
 
-	private final Set<File> mixinMappings = Collections.synchronizedSet(new HashSet<>());
+	private final ConfigurableFileCollection mixinMappings;
 	private final MappingSet[] srcMappingCache = new MappingSet[2];
 	private final Mercury[] srcMercuryCache = new Mercury[2];
 	private final Map<String, NamedDomainObjectProvider<Configuration>> lazyConfigurations = new HashMap<>();
@@ -80,6 +80,7 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 		this.project = project;
 		// Initiate with newInstance to allow gradle to decorate our extension
 		this.mixinApExtension = project.getObjects().newInstance(MixinExtensionImpl.class, project);
+		this.mixinMappings = project.getObjects().fileCollection();
 		this.loomFiles = files;
 		this.unmappedMods = project.files();
 		this.forgeExtension = Suppliers.memoize(() -> isForge() ? project.getObjects().newInstance(ForgeExtensionImpl.class, project, this) : null);
@@ -97,15 +98,15 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 	}
 
 	@Override
-	public synchronized File getNextMixinMappings() {
-		File mixinMapping = new File(getFiles().getProjectBuildCache(), "mixin-map-" + getMappingsProvider().mappingsIdentifier() + "." + mixinMappings.size() + ".tiny");
-		mixinMappings.add(mixinMapping);
+	public synchronized File getMixinMappings(SourceSet sourceSet) {
+		File mixinMapping = new File(getFiles().getProjectBuildCache(), "mixin-map-" + getMappingsProvider().mappingsIdentifier() + "." + sourceSet.getName() + ".tiny");
+		mixinMappings.from(getProject().files(mixinMapping));
 		return mixinMapping;
 	}
 
 	@Override
-	public Set<File> getAllMixinMappings() {
-		return mixinMappings;
+	public FileCollection getAllMixinMappings() {
+		return mixinMappings.filter(File::exists);
 	}
 
 	@Override
@@ -160,8 +161,8 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 	}
 
 	@Override
-	public NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name) {
-		NamedDomainObjectProvider<Configuration> provider = project.getConfigurations().register(name);
+	public NamedDomainObjectProvider<Configuration> createLazyConfiguration(String name, Action<? super Configuration> configurationAction) {
+		NamedDomainObjectProvider<Configuration> provider = project.getConfigurations().register(name, configurationAction);
 
 		if (lazyConfigurations.containsKey(name)) {
 			throw new IllegalStateException("Duplicate configuration name" + name);

src/main/java/net/fabricmc/loom/extension/MixinExtensionApiImpl.java

@@ -29,7 +29,7 @@ import java.util.Objects;
 import org.gradle.api.Action;
 import org.gradle.api.InvalidUserDataException;
 import org.gradle.api.Project;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.JavaPluginExtension;
 import org.gradle.api.provider.Property;
 import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.SourceSet;
@@ -111,8 +111,7 @@ public abstract class MixinExtensionApiImpl implements MixinExtensionAPI {
 
 	private SourceSet resolveSourceSet(String sourceSetName) {
 		// try to find sourceSet with name sourceSetName in this project
-		SourceSet sourceSet = project.getConvention().getPlugin(JavaPluginConvention.class)
-				.getSourceSets().findByName(sourceSetName);
+		SourceSet sourceSet = project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets().findByName(sourceSetName);
 
 		if (sourceSet == null) {
 			throw new InvalidUserDataException("No sourceSet " + sourceSetName + " was found");

src/main/java/net/fabricmc/loom/extension/MixinExtensionImpl.java

@@ -38,8 +38,8 @@ import org.gradle.api.Project;
 import org.gradle.api.Task;
 import org.gradle.api.UnknownTaskException;
 import org.gradle.api.artifacts.Configuration;
-import org.gradle.api.plugins.BasePluginConvention;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.BasePluginExtension;
+import org.gradle.api.plugins.JavaPluginExtension;
 import org.gradle.api.provider.Property;
 import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.Input;
@@ -67,12 +67,11 @@ public class MixinExtensionImpl extends MixinExtensionApiImpl implements MixinEx
 	}
 
 	private String getDefaultMixinRefmapName() {
-		String defaultRefmapName = project.getConvention().getPlugin(BasePluginConvention.class).getArchivesBaseName() + "-refmap.json";
+		String defaultRefmapName = project.getExtensions().getByType(BasePluginExtension.class).getArchivesName().get() + "-refmap.json";
 
 		if (project.getRootProject() != project) {
 			defaultRefmapName = project.getConvention().getPlugin(BasePluginConvention.class).getArchivesBaseName() + "-" + project.getPath().replaceFirst(":", "").replace(':', '_') + "-refmap.json";
 		}
-
 		project.getLogger().info("Could not find refmap definition, will be using default name: " + defaultRefmapName);
 		return defaultRefmapName;
 	}
@@ -81,7 +80,7 @@ public class MixinExtensionImpl extends MixinExtensionApiImpl implements MixinEx
 	protected PatternSet add0(SourceSet sourceSet, Provider<String> refmapName) {
 		if (!super.getUseLegacyMixinAp().get()) throw new IllegalStateException("You need to set useLegacyMixinAp = true to configure Mixin annotation processor.");
 
-		PatternSet pattern = new PatternSet().setIncludes(Collections.singletonList("*.json"));
+		PatternSet pattern = new PatternSet().setIncludes(Collections.singletonList("**/*.json"));
 		MixinExtension.setMixinInformationContainer(sourceSet, new MixinExtension.MixinInformationContainer(sourceSet, refmapName, pattern));
 
 		isDefault = false;
@@ -92,7 +91,7 @@ public class MixinExtensionImpl extends MixinExtensionApiImpl implements MixinEx
 	@Override
 	@NotNull
 	public Stream<SourceSet> getMixinSourceSetsStream() {
-		return project.getConvention().getPlugin(JavaPluginConvention.class).getSourceSets().stream()
+		return project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets().stream()
 				.filter(sourceSet -> MixinExtension.getMixinInformationContainer(sourceSet) != null);
 	}
 
@@ -127,7 +126,7 @@ public class MixinExtensionImpl extends MixinExtensionApiImpl implements MixinEx
 	@Override
 	public void init() {
 		if (isDefault) {
-			project.getConvention().getPlugin(JavaPluginConvention.class).getSourceSets().forEach(this::add);
+			project.getExtensions().getByType(JavaPluginExtension.class).getSourceSets().forEach(this::add);
 		}
 
 		isDefault = false;

src/main/java/net/fabricmc/loom/task/AbstractRemapJarTask.java

@@ -0,0 +1,123 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task;
+
+import java.io.IOException;
+import java.nio.file.Path;
+
+import javax.inject.Inject;
+
+import org.gradle.api.Action;
+import org.gradle.api.file.ConfigurableFileCollection;
+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.InputFiles;
+import org.gradle.jvm.tasks.Jar;
+import org.gradle.workers.WorkAction;
+import org.gradle.workers.WorkParameters;
+import org.gradle.workers.WorkQueue;
+import org.gradle.workers.WorkerExecutor;
+
+import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
+import net.fabricmc.loom.util.ZipReprocessorUtil;
+
+public abstract class AbstractRemapJarTask extends Jar {
+	@InputFile
+	public abstract RegularFileProperty getInputFile();
+
+	@InputFiles
+	public abstract ConfigurableFileCollection getClasspath();
+
+	@Input
+	public abstract Property<String> getSourceNamespace();
+
+	@Input
+	public abstract Property<String> getTargetNamespace();
+
+	@Inject
+	protected abstract WorkerExecutor getWorkerExecutor();
+
+	@Inject
+	public AbstractRemapJarTask() {
+		getSourceNamespace().convention(MappingsNamespace.NAMED.toString()).finalizeValueOnRead();
+		getTargetNamespace().convention(MappingsNamespace.INTERMEDIARY.toString()).finalizeValueOnRead();
+	}
+
+	public final <P extends AbstractRemapParams> void submitWork(Class<? extends AbstractRemapAction<P>> workAction, Action<P> action) {
+		final WorkQueue workQueue = getWorkerExecutor().noIsolation();
+
+		workQueue.submit(workAction, params -> {
+			params.getInputFile().set(getInputFile());
+			params.getOutputFile().set(getArchiveFile());
+
+			params.getSourceNamespace().set(getSourceNamespace());
+			params.getTargetNamespace().set(getTargetNamespace());
+
+			params.getArchivePreserveFileTimestamps().set(isPreserveFileTimestamps());
+			params.getArchiveReproducibleFileOrder().set(isReproducibleFileOrder());
+
+			action.execute(params);
+		});
+	}
+
+	public interface AbstractRemapParams extends WorkParameters {
+		RegularFileProperty getInputFile();
+		RegularFileProperty getOutputFile();
+
+		Property<String> getSourceNamespace();
+		Property<String> getTargetNamespace();
+
+		Property<Boolean> getArchivePreserveFileTimestamps();
+		Property<Boolean> getArchiveReproducibleFileOrder();
+	}
+
+	public abstract static class AbstractRemapAction<T extends AbstractRemapParams> implements WorkAction<T> {
+		protected final Path inputFile;
+		protected final Path outputFile;
+
+		@Inject
+		public AbstractRemapAction() {
+			inputFile = getParameters().getInputFile().getAsFile().get().toPath();
+			outputFile = getParameters().getOutputFile().getAsFile().get().toPath();
+		}
+
+		protected void rewriteJar() throws IOException {
+			final boolean isReproducibleFileOrder = getParameters().getArchiveReproducibleFileOrder().get();
+			final boolean isPreserveFileTimestamps = getParameters().getArchivePreserveFileTimestamps().get();
+
+			if (isReproducibleFileOrder || !isPreserveFileTimestamps) {
+				ZipReprocessorUtil.reprocessZip(outputFile.toFile(), isReproducibleFileOrder, isPreserveFileTimestamps);
+			}
+		}
+	}
+
+	@Deprecated
+	@InputFile
+	public RegularFileProperty getInput() {
+		return getInputFile();
+	}
+}

src/main/java/net/fabricmc/loom/task/AbstractRunTask.java

@@ -31,6 +31,7 @@ import java.util.List;
 import java.util.function.Function;
 
 import org.gradle.api.Project;
+import org.gradle.api.specs.Spec;
 import org.gradle.api.tasks.JavaExec;
 
 import net.fabricmc.loom.configuration.ide.RunConfig;
@@ -44,8 +45,9 @@ public abstract class AbstractRunTask extends JavaExec {
 		setGroup(Constants.TaskGroup.FABRIC);
 		this.config = configProvider.apply(getProject());
 
-		setClasspath(config.sourceSet.getRuntimeClasspath());
+		setClasspath(config.sourceSet.getRuntimeClasspath().filter(new LibraryFilter()));
 		args(config.programArgs);
+		getMainClass().set(config.mainClass);
 	}
 
 	@Override
@@ -65,11 +67,6 @@ public abstract class AbstractRunTask extends JavaExec {
 		super.setWorkingDir(dir);
 	}
 
-	@Override
-	public String getMain() {
-		return config.mainClass;
-	}
-
 	@Override
 	public List<String> getJvmArgs() {
 		List<String> superArgs = super.getJvmArgs();
@@ -77,4 +74,22 @@ public abstract class AbstractRunTask extends JavaExec {
 		args.addAll(config.vmArgs);
 		return args;
 	}
+
+	private class LibraryFilter implements Spec<File> {
+		private List<String> excludedLibraryPaths = null;
+
+		@Override
+		public boolean isSatisfiedBy(File element) {
+			if (excludedLibraryPaths == null) {
+				excludedLibraryPaths = config.getExcludedLibraryPaths(getProject());
+			}
+
+			if (excludedLibraryPaths.contains(element.getAbsolutePath())) {
+				getProject().getLogger().debug("Excluding library {} from {} run config", element.getName(), config.configName);
+				return false;
+			}
+
+			return true;
+		}
+	}
 }

src/main/java/net/fabricmc/loom/task/DownloadAssetsTask.java

@@ -30,7 +30,6 @@ import org.gradle.api.Project;
 import org.gradle.api.tasks.TaskAction;
 
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.configuration.providers.minecraft.MinecraftNativesProvider;
 import net.fabricmc.loom.configuration.providers.minecraft.assets.MinecraftAssetsProvider;
 
 public class DownloadAssetsTask extends AbstractLoomTask {
@@ -40,6 +39,5 @@ public class DownloadAssetsTask extends AbstractLoomTask {
 		LoomGradleExtension extension = getExtension();
 
 		MinecraftAssetsProvider.provide(extension.getMinecraftProvider(), project);
-		MinecraftNativesProvider.provide(project);
 	}
 }

src/main/java/net/fabricmc/loom/task/ExtractNativesTask.java

@@ -0,0 +1,50 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task;
+
+import java.io.File;
+
+import javax.inject.Inject;
+
+import org.gradle.api.tasks.Sync;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.util.Constants;
+
+public abstract class ExtractNativesTask extends Sync {
+	@Inject
+	public ExtractNativesTask() {
+		// Is there a lazy way to do this for many files? - Doesnt seem there is...
+		for (File nativeFile : getProject().getConfigurations().getByName(Constants.Configurations.MINECRAFT_NATIVES).getFiles()) {
+			from(getProject().zipTree(nativeFile), copySpec -> {
+				copySpec.exclude("META-INF/**");
+			});
+		}
+
+		into(LoomGradleExtension.get(getProject()).getFiles().getNativesDirectory(getProject()));
+
+		setDescription("Downloads and extracts the minecraft natives");
+	}
+}

src/main/java/net/fabricmc/loom/task/GenerateSourcesTask.java

@@ -49,6 +49,7 @@ import org.gradle.api.provider.MapProperty;
 import org.gradle.api.provider.Property;
 import org.gradle.api.tasks.Input;
 import org.gradle.api.tasks.InputFile;
+import org.gradle.api.tasks.InputFiles;
 import org.gradle.api.tasks.TaskAction;
 import org.gradle.workers.WorkAction;
 import org.gradle.workers.WorkParameters;
@@ -89,6 +90,9 @@ public abstract class GenerateSourcesTask extends AbstractLoomTask {
 	@Input
 	public abstract MapProperty<String, String> getOptions();
 
+	@InputFiles
+	public abstract ConfigurableFileCollection getClasspath();
+
 	@Inject
 	public abstract WorkerExecutor getWorkerExecutor();
 
@@ -102,6 +106,12 @@ public abstract class GenerateSourcesTask extends AbstractLoomTask {
 		Objects.requireNonNull(getDecompilerConstructor(this.decompiler.getClass().getCanonicalName()),
 				"%s must have a no args constructor".formatted(this.decompiler.getClass().getCanonicalName()));
 
+		FileCollection decompilerClasspath = decompiler.getBootstrapClasspath(getProject());
+
+		if (decompilerClasspath != null) {
+			getClasspath().from(decompilerClasspath);
+		}
+
 		getOutputs().upToDateWhen((o) -> false);
 		getMaxMemory().convention(4096L).finalizeValueOnRead();
 		getOptions().finalizeValueOnRead();
@@ -179,6 +189,7 @@ public abstract class GenerateSourcesTask extends AbstractLoomTask {
 			spec.forkOptions(forkOptions -> {
 				forkOptions.setMaxHeapSize("%dm".formatted(getMaxMemory().get()));
 				forkOptions.systemProperty(WorkerDaemonClientsManagerHelper.MARKER_PROP, jvmMarkerValue);
+				forkOptions.bootstrapClasspath(getClasspath());
 			});
 		});
 	}

src/main/java/net/fabricmc/loom/task/LoomTasks.java

@@ -24,21 +24,13 @@
 
 package net.fabricmc.loom.task;
 
-import java.io.File;
-import java.io.IOException;
-import java.io.UncheckedIOException;
-
 import com.google.common.base.Preconditions;
 import org.gradle.api.Project;
 import org.gradle.api.tasks.TaskContainer;
 import org.gradle.api.tasks.TaskProvider;
 
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.api.decompilers.LoomDecompiler;
-import net.fabricmc.loom.api.decompilers.architectury.ArchitecturyLoomDecompiler;
 import net.fabricmc.loom.configuration.ide.RunConfigSettings;
-import net.fabricmc.loom.configuration.ide.SetupIntelijRunConfigs;
-import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
 import net.fabricmc.loom.util.Constants;
 
 public final class LoomTasks {
@@ -53,13 +45,13 @@ public final class LoomTasks {
 			t.getOutputs().upToDateWhen(o -> false);
 		});
 
-		tasks.register("remapJar", RemapJarTask.class, t -> {
-			t.setDescription("Remaps the built project jar to intermediary mappings.");
-			t.setGroup(Constants.TaskGroup.FABRIC);
-		});
+		RemapTaskConfiguration.setupRemap(project);
 
-		tasks.register("downloadAssets", DownloadAssetsTask.class, t -> t.setDescription("Downloads required assets for Fabric."));
-		tasks.register("remapSourcesJar", RemapSourcesJarTask.class, t -> t.setDescription("Remaps the project sources jar to intermediary names."));
+		TaskProvider<ExtractNativesTask> extractNatives = tasks.register("extractNatives", ExtractNativesTask.class);
+		tasks.register("downloadAssets", DownloadAssetsTask.class, t -> {
+			t.dependsOn(extractNatives);
+			t.setDescription("Downloads required assets for Fabric.");
+		});
 
 		TaskProvider<ValidateAccessWidenerTask> validateAccessWidener = tasks.register("validateAccessWidener", ValidateAccessWidenerTask.class, t -> {
 			t.setDescription("Validate all the rules in the access widener against the Minecraft jar");
@@ -146,51 +138,15 @@ public final class LoomTasks {
 	}
 
 	private static void registerDecompileTasks(TaskContainer tasks, Project project) {
-		LoomGradleExtension extension = LoomGradleExtension.get(project);
-
-		project.afterEvaluate(p -> {
-			MappingsProviderImpl mappingsProvider = extension.getMappingsProvider();
-
-			if (mappingsProvider.mappedProvider == null) {
-				// If this is ever null something has gone badly wrong,
-				// for some reason for another this afterEvaluate still gets called when something has gone badly
-				// wrong, returning here seems to produce nicer errors.
-				return;
-			}
-
-			File mappedJar = mappingsProvider.mappedProvider.getMappedJar();
-
-			if (mappingsProvider.hasUnpickDefinitions()) {
-				File outputJar = mappingsProvider.mappedProvider.getUnpickedJar();
-
-				tasks.register("unpickJar", UnpickJarTask.class, unpickJarTask -> {
-					unpickJarTask.getUnpickDefinitions().set(mappingsProvider.getUnpickDefinitionsFile());
-					unpickJarTask.getInputJar().set(mappingsProvider.mappedProvider.getMappedJar());
-					unpickJarTask.getOutputJar().set(outputJar);
-				});
-
-				mappedJar = outputJar;
-			}
-
-			final File inputJar = mappedJar;
-
-			extension.getGameDecompilers().finalizeValue();
-
-			for (LoomDecompiler decompiler : extension.getGameDecompilers().get()) {
-				String taskName = "genSourcesWith" + decompiler.name();
-				// Decompiler will be passed to the constructor of GenerateSourcesTask
-				tasks.register(taskName, GenerateSourcesTask.class, decompiler).configure(task -> {
-					task.setDescription("Decompile minecraft using %s.".formatted(decompiler.name()));
-					task.setGroup(Constants.TaskGroup.FABRIC);
-					task.getInputJar().set(inputJar);
-
-					if (mappingsProvider.hasUnpickDefinitions()) {
-						task.dependsOn(tasks.named("unpickJar"));
-					}
-
-					task.dependsOn(tasks.named("validateAccessWidener"));
-				});
-			}
+		LoomGradleExtension.get(project).getGameDecompilers().configureEach(decompiler -> {
+			String taskName = "genSourcesWith" + decompiler.name();
+			// Decompiler will be passed to the constructor of GenerateSourcesTask
+			tasks.register(taskName, GenerateSourcesTask.class, decompiler).configure(task -> {
+				task.setDescription("Decompile minecraft using %s.".formatted(decompiler.name()));
+				task.setGroup(Constants.TaskGroup.FABRIC);
+				task.dependsOn(tasks.named("validateAccessWidener"));
+			});
+		});
 
 			for (ArchitecturyLoomDecompiler decompiler : extension.getArchGameDecompilers().get()) {
 				String taskName = "genSourcesWith" + decompiler.name();
@@ -206,12 +162,11 @@ public final class LoomTasks {
 				});
 			}
 
-			tasks.register("genSources", task -> {
-				task.setDescription("Decompile minecraft using the default decompiler.");
-				task.setGroup(Constants.TaskGroup.FABRIC);
+		tasks.register("genSources", task -> {
+			task.setDescription("Decompile minecraft using the default decompiler.");
+			task.setGroup(Constants.TaskGroup.FABRIC);
 
-				task.dependsOn(project.getTasks().named("genSourcesWithCfr"));
-			});
+			task.dependsOn(project.getTasks().named("genSourcesWithCfr"));
 		});
 	}
 }

src/main/java/net/fabricmc/loom/task/MigrateMappingsTask.java

@@ -42,7 +42,7 @@ import org.gradle.api.IllegalDependencyNotation;
 import org.gradle.api.JavaVersion;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Dependency;
-import org.gradle.api.plugins.JavaPluginConvention;
+import org.gradle.api.plugins.JavaPluginExtension;
 import org.gradle.api.tasks.TaskAction;
 import org.gradle.api.tasks.options.Option;
 
@@ -171,12 +171,7 @@ public class MigrateMappingsTask extends AbstractLoomTask {
 		project.getLogger().lifecycle(":remapping");
 		Mercury mercury = SourceRemapper.createMercuryWithClassPath(project, false);
 
-		final JavaPluginConvention convention = project.getConvention().findPlugin(JavaPluginConvention.class);
-		final JavaVersion javaVersion = convention != null
-				?
-				convention.getSourceCompatibility()
-				:
-				JavaVersion.current();
+		final JavaVersion javaVersion = project.getExtensions().getByType(JavaPluginExtension.class).getSourceCompatibility();
 		mercury.setSourceCompatibility(javaVersion.toString());
 
 		mercury.getClassPath().add(minecraftMappedProvider.getMappedJar().toPath());

src/main/java/net/fabricmc/loom/task/RemapJarTask.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2021 FabricMC
+ * Copyright (c) 2021 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,443 +24,306 @@
 
 package net.fabricmc.loom.task;
 
-import java.io.BufferedReader;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.io.UncheckedIOException;
-import java.io.Writer;
-import java.nio.charset.StandardCharsets;
-import java.nio.file.FileAlreadyExistsException;
-import java.nio.file.FileSystem;
+import java.io.Serializable;
 import java.nio.file.Files;
-import java.nio.file.NoSuchFileException;
-import java.nio.file.Path;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.LinkedHashSet;
+import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 import java.util.jar.Manifest;
+import java.util.stream.Collectors;
+
+import javax.inject.Inject;
 
 import com.google.common.base.Preconditions;
-import dev.architectury.tinyremapper.IMappingProvider;
-import dev.architectury.tinyremapper.TinyRemapper;
-import dev.architectury.tinyremapper.TinyUtils;
-import dev.architectury.tinyremapper.extension.mixin.MixinExtension;
-import org.cadixdev.at.AccessTransformSet;
-import org.cadixdev.at.io.AccessTransformFormats;
-import org.cadixdev.lorenz.MappingSet;
-import org.gradle.api.Action;
-import org.gradle.api.Project;
+import com.google.gson.JsonObject;
 import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.file.ConfigurableFileCollection;
 import org.gradle.api.file.FileCollection;
-import org.gradle.api.file.RegularFileProperty;
 import org.gradle.api.plugins.JavaPlugin;
+import org.gradle.api.provider.ListProperty;
 import org.gradle.api.provider.Property;
-import org.gradle.api.provider.SetProperty;
+import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.Input;
-import org.gradle.api.tasks.InputFile;
+import org.gradle.api.tasks.InputFiles;
+import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.TaskAction;
-import org.gradle.jvm.tasks.Jar;
-import org.jetbrains.annotations.ApiStatus;
+import org.objectweb.asm.commons.Remapper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
+import net.fabricmc.accesswidener.AccessWidenerReader;
+import net.fabricmc.accesswidener.AccessWidenerRemapper;
+import net.fabricmc.accesswidener.AccessWidenerWriter;
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.build.JarRemapper;
+import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
 import net.fabricmc.loom.build.MixinRefmapHelper;
-import net.fabricmc.loom.build.nesting.EmptyNestedJarProvider;
+import net.fabricmc.loom.build.nesting.IncludedJarFactory;
 import net.fabricmc.loom.build.nesting.JarNester;
-import net.fabricmc.loom.build.nesting.MergedNestedJarProvider;
-import net.fabricmc.loom.build.nesting.NestedDependencyProvider;
-import net.fabricmc.loom.build.nesting.NestedJarPathProvider;
-import net.fabricmc.loom.build.nesting.NestedJarProvider;
-import net.fabricmc.loom.configuration.JarManifestConfiguration;
 import net.fabricmc.loom.configuration.accesswidener.AccessWidenerFile;
-import net.fabricmc.loom.configuration.accesswidener.AccessWidenerJarProcessor;
-import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
+import net.fabricmc.loom.extension.MixinExtension;
+import net.fabricmc.loom.task.service.JarManifestService;
+import net.fabricmc.loom.task.service.MappingsService;
 import net.fabricmc.loom.util.Constants;
-import net.fabricmc.loom.util.FileSystemUtil;
-import net.fabricmc.loom.util.LfWriter;
-import net.fabricmc.loom.util.SourceRemapper;
-import net.fabricmc.loom.util.TinyRemapperHelper;
-import net.fabricmc.loom.util.ZipReprocessorUtil;
 import net.fabricmc.loom.util.ZipUtils;
-import net.fabricmc.loom.util.aw2at.Aw2At;
-import net.fabricmc.lorenztiny.TinyMappingsReader;
-import net.fabricmc.mappingio.tree.MappingTree;
-import net.fabricmc.stitch.util.Pair;
+import net.fabricmc.tinyremapper.InputTag;
+import net.fabricmc.tinyremapper.OutputConsumerPath;
+import net.fabricmc.tinyremapper.TinyRemapper;
+import net.fabricmc.tinyremapper.TinyUtils;
 
-public class RemapJarTask extends Jar {
+public abstract class RemapJarTask extends AbstractRemapJarTask {
 	private static final String MANIFEST_PATH = "META-INF/MANIFEST.MF";
 
-	private final RegularFileProperty input;
-	private final Property<Boolean> addNestedDependencies;
-	private final Property<Boolean> addDefaultNestedDependencies;
-	private final Property<Boolean> remapAccessWidener;
-	private final List<Action<TinyRemapper.Builder>> remapOptions = new ArrayList<>();
-	private final Property<String> fromM;
-	private final Property<String> toM;
-	private final SetProperty<String> atAccessWideners;
-	public JarRemapper jarRemapper;
-	private FileCollection classpath;
-	private final Set<Object> nestedPaths = new LinkedHashSet<>();
+	@InputFiles
+	public abstract ConfigurableFileCollection getNestedJars();
 
+	@Input
+	public abstract Property<Boolean> getAddNestedDependencies();
+
+	@Inject
 	public RemapJarTask() {
 		super();
-		LoomGradleExtension extension = LoomGradleExtension.get(getProject());
-		input = getProject().getObjects().fileProperty();
-		addNestedDependencies = getProject().getObjects().property(Boolean.class)
-				.convention(false);
-		addDefaultNestedDependencies = getProject().getObjects().property(Boolean.class)
-				.convention(true);
-		remapAccessWidener = getProject().getObjects().property(Boolean.class)
-				.convention(false);
-		fromM = getProject().getObjects().property(String.class)
-				.convention("named");
-		toM = getProject().getObjects().property(String.class)
-				.convention(SourceRemapper.intermediary(getProject()));
-		atAccessWideners = getProject().getObjects().setProperty(String.class)
-				.empty();
 
-		if (!extension.getMixin().getUseLegacyMixinAp().get()) {
-			remapOptions.add(b -> b.extension(new MixinExtension()));
-		}
+		getClasspath().from(getProject().getConfigurations().getByName(JavaPlugin.COMPILE_CLASSPATH_CONFIGURATION_NAME));
+		getAddNestedDependencies().convention(true).finalizeValueOnRead();
+
+		Configuration includeConfiguration = getProject().getConfigurations().getByName(Constants.Configurations.INCLUDE);
+		getNestedJars().from(new IncludedJarFactory(getProject()).getNestedJars(includeConfiguration));
 	}
 
 	@TaskAction
-	public void doTask() throws Throwable {
-		boolean singleRemap = false;
+	public void run() {
+		final LoomGradleExtension extension = LoomGradleExtension.get(getProject());
 
-		if (jarRemapper == null) {
-			singleRemap = true;
-			jarRemapper = new JarRemapper();
-		}
-
-		scheduleRemap(singleRemap || LoomGradleExtension.get(getProject()).isRootProject());
-
-		if (singleRemap) {
-			jarRemapper.remap(getProject());
-		}
-
-		convertAwToAt();
-	}
-
-	public void scheduleRemap(boolean isMainRemapTask) throws Throwable {
-		Project project = getProject();
-		LoomGradleExtension extension = LoomGradleExtension.get(getProject());
-		Path input = this.getInput().getAsFile().get().toPath();
-		Path output = this.getArchivePath().toPath();
-
-		if (!Files.exists(input)) {
-			throw new FileNotFoundException(input.toString());
-		}
-
-		MappingsProviderImpl mappingsProvider = extension.getMappingsProvider();
-
-		String fromM = this.fromM.get();
-		String toM = this.toM.get();
-
-		if (isMainRemapTask) {
-			jarRemapper.addToClasspath(getRemapClasspath());
-
-			jarRemapper.addMappings(TinyRemapperHelper.create((fromM.equals("srg") || toM.equals("srg")) && extension.shouldGenerateSrgTiny() ? mappingsProvider.getMappingsWithSrg() : mappingsProvider.getMappings(), fromM, toM, false));
-		}
-
-		for (File mixinMapFile : extension.getAllMixinMappings()) {
-			if (mixinMapFile.exists()) {
-				IMappingProvider provider = TinyUtils.createTinyMappingProvider(mixinMapFile.toPath(), fromM, "intermediary");
-				jarRemapper.addMappings(!toM.equals("intermediary") ? remapToSrg(extension, provider, "intermediary", toM) : provider);
+		submitWork(RemapAction.class, params -> {
+			if (getAddNestedDependencies().get()) {
+				params.getNestedJars().from(getNestedJars());
 			}
-		}
 
-		// Add remap options to the jar remapper
-		jarRemapper.addOptions(this.remapOptions);
+			params.getJarManifestService().set(JarManifestService.get(getProject()));
+			params.getRemapClasspath().from(getClasspath());
+			params.getMappings().add(MappingsService.createDefault(getProject(), getSourceNamespace().get(), getTargetNamespace().get()));
 
-		project.getLogger().info(":scheduling remap " + input.getFileName() + " from " + fromM + " to " + toM);
+			final boolean legacyMixin = extension.getMixin().getUseLegacyMixinAp().get();
+			params.getUseMixinExtension().set(!legacyMixin);
 
-		NestedJarProvider nestedJarProvider = getNestedJarProvider();
-		nestedJarProvider.prepare(getProject());
-
-		jarRemapper.scheduleRemap(input, output)
-				.supplyAccessWidener((remapData, remapper) -> {
-					if (getRemapAccessWidener().getOrElse(false) && extension.getAccessWidenerPath().isPresent()) {
-						AccessWidenerJarProcessor accessWidenerJarProcessor = extension.getJarProcessorManager().getByType(AccessWidenerJarProcessor.class);
-						byte[] data;
-
-						try {
-							data = accessWidenerJarProcessor.getRemappedAccessWidener(remapper, toM);
-						} catch (IOException e) {
-							throw new RuntimeException("Failed to remap access widener", e);
-						}
-
-						AccessWidenerFile awFile = AccessWidenerFile.fromModJar(remapData.input);
-						Preconditions.checkNotNull(awFile, "Failed to find accessWidener in fabric.mod.json / architectury.common.json: " + remapData.input);
-
-						return Pair.of(awFile.name(), data);
-					}
-
-					return null;
-				})
-				.complete((data, accessWidener) -> {
-					if (!Files.exists(output)) {
-						throw new RuntimeException("Failed to remap " + input + " to " + output + " - file missing!");
-					}
-
-					if (extension.getMixin().getUseLegacyMixinAp().get()) {
-						if (MixinRefmapHelper.addRefmapName(project, output)) {
-							project.getLogger().debug("Transformed mixin reference maps in output JAR!");
-						}
-					} else if (extension.isForge()) {
-						throw new RuntimeException("Forge must have useLegacyMixinAp enabled");
-					}
-
-					if (getAddNestedDependencies().getOrElse(false)) {
-						JarNester.nestJars(nestedJarProvider.provide(), output.toFile(), project.getLogger());
-					}
-
-					if (accessWidener != null) {
-						try {
-							ZipUtils.replace(data.output, accessWidener.getLeft(), accessWidener.getRight());
-						} catch (IOException e) {
-							throw new UncheckedIOException("Failed to replace access widener in output jar", e);
-						}
-					}
-
-					if (!extension.isForge()) {
-						// Add data to the manifest
-						try {
-							int count = ZipUtils.transform(data.output, Map.of(MANIFEST_PATH, bytes -> {
-								var manifest = new Manifest(new ByteArrayInputStream(bytes));
-								var manifestConfiguration = new JarManifestConfiguration(project);
-
-								manifestConfiguration.configure(manifest);
-								manifest.getMainAttributes().putValue("Fabric-Mapping-Namespace", toM);
-
-								ByteArrayOutputStream out = new ByteArrayOutputStream();
-								manifest.write(out);
-								return out.toByteArray();
-							}));
-
-							Preconditions.checkState(count > 0, "Did not transform any jar manifest");
-						} catch (IOException e) {
-							throw new UncheckedIOException("Failed to transform jar manifest", e);
-						}
-					}
-
-					if (isReproducibleFileOrder() || !isPreserveFileTimestamps()) {
-						try {
-							ZipReprocessorUtil.reprocessZip(output.toFile(), isReproducibleFileOrder(), isPreserveFileTimestamps());
-						} catch (IOException e) {
-							throw new RuntimeException("Failed to re-process jar", e);
-						}
-					}
-				});
+			if (legacyMixin) {
+				params.getMixinMappings().from(extension.getAllMixinMappings());
+				setupLegacyMixinRefmapRemapping(params);
+			}
+		});
 	}
 
-	private NestedJarProvider getNestedJarProvider() {
-		if (!LoomGradleExtension.get(getProject()).supportsInclude()) {
-			return EmptyNestedJarProvider.INSTANCE;
-		}
+	private void setupLegacyMixinRefmapRemapping(RemapParams params) {
+		final LoomGradleExtension extension = LoomGradleExtension.get(getProject());
+		final MixinExtension mixinExtension = extension.getMixin();
 
-		Configuration includeConfiguration = getProject().getConfigurations().getByName(Constants.Configurations.INCLUDE);
+		final JsonObject fabricModJson = MixinRefmapHelper.readFabricModJson(getInputFile().getAsFile().get());
 
-		if (!addDefaultNestedDependencies.getOrElse(true)) {
-			return new NestedJarPathProvider(nestedPaths);
-		}
-
-		NestedJarProvider baseProvider = NestedDependencyProvider.createNestedDependencyProviderFromConfiguration(getProject(), includeConfiguration);
-
-		if (nestedPaths.isEmpty()) {
-			return baseProvider;
-		}
-
-		return new MergedNestedJarProvider(
-				baseProvider,
-				new NestedJarPathProvider(nestedPaths)
-		);
-	}
-
-	private IMappingProvider remapToSrg(LoomGradleExtension extension, IMappingProvider parent, String from, String to) throws IOException {
-		MappingTree mappings = (from.equals("srg") || to.equals("srg")) && extension.shouldGenerateSrgTiny() ? extension.getMappingsProvider().getMappingsWithSrg() : extension.getMappingsProvider().getMappings();
-
-		return sink -> {
-			parent.load(new IMappingProvider.MappingAcceptor() {
-				@Override
-				public void acceptClass(String srcName, String dstName) {
-					String srgName = mappings.getClasses()
-							.stream()
-							.filter(it -> Objects.equals(it.getName(from), dstName))
-							.findFirst()
-							.map(it -> it.getName(to))
-							.orElse(dstName);
-					sink.acceptClass(srcName, srgName);
-				}
-
-				@Override
-				public void acceptMethod(IMappingProvider.Member method, String dstName) {
-					String srgName = mappings.getClasses()
-							.stream()
-							.flatMap(it -> it.getMethods().stream())
-							.filter(it -> Objects.equals(it.getName(from), dstName))
-							.findFirst()
-							.map(it -> it.getName(to))
-							.orElse(dstName);
-					sink.acceptMethod(method, srgName);
-				}
-
-				@Override
-				public void acceptField(IMappingProvider.Member field, String dstName) {
-					String srgName = mappings.getClasses()
-							.stream()
-							.flatMap(it -> it.getFields().stream())
-							.filter(it -> Objects.equals(it.getName(from), dstName))
-							.findFirst()
-							.map(it -> it.getName(to))
-							.orElse(dstName);
-					sink.acceptField(field, srgName);
-				}
-
-				@Override
-				public void acceptMethodArg(IMappingProvider.Member method, int lvIndex, String dstName) {
-				}
-
-				@Override
-				public void acceptMethodVar(IMappingProvider.Member method, int lvIndex, int startOpIdx, int asmIndex, String dstName) {
-				}
-			});
-		};
-	}
-
-	private Path[] getRemapClasspath() {
-		FileCollection files = this.classpath;
-
-		if (files == null) {
-			files = getProject().getConfigurations().getByName(JavaPlugin.COMPILE_CLASSPATH_CONFIGURATION_NAME);
-		}
-
-		return files.getFiles().stream()
-				.map(File::toPath)
-				.filter(Files::exists)
-				.toArray(Path[]::new);
-	}
-
-	private void convertAwToAt() throws IOException {
-		if (!this.atAccessWideners.isPresent()) {
+		if (fabricModJson == null) {
+			getProject().getLogger().warn("Could not find fabric.mod.json file in: " + getInputFile().getAsFile().get().getName());
 			return;
 		}
 
-		Set<String> atAccessWideners = this.atAccessWideners.get();
+		final Collection<String> allMixinConfigs = MixinRefmapHelper.getMixinConfigurationFiles(fabricModJson);
 
-		if (atAccessWideners.isEmpty()) {
-			return;
+		for (SourceSet sourceSet : mixinExtension.getMixinSourceSets()) {
+			MixinExtension.MixinInformationContainer container = Objects.requireNonNull(
+					MixinExtension.getMixinInformationContainer(sourceSet)
+			);
+
+			String[] rootPaths = sourceSet.getResources().getSrcDirs().stream()
+					.map(root -> {
+						String rootPath = root.getAbsolutePath().replace("\\", "/");
+
+						if (rootPath.charAt(rootPath.length() - 1) != '/') {
+							rootPath += '/';
+						}
+
+						return rootPath;
+					})
+					.toArray(String[]::new);
+
+			final String refmapName = container.refmapNameProvider().get();
+			final List<String> mixinConfigs = container.sourceSet().getResources()
+					.matching(container.mixinConfigPattern())
+					.getFiles()
+					.stream()
+					.map(file -> {
+						String s = file.getAbsolutePath().replace("\\", "/");
+
+						for (String rootPath : rootPaths) {
+							if (s.startsWith(rootPath)) {
+								s = s.substring(rootPath.length());
+							}
+						}
+
+						return s;
+					})
+					.filter(allMixinConfigs::contains)
+					.toList();
+
+			params.getMixinData().add(new RemapParams.RefmapData(mixinConfigs, refmapName));
 		}
+	}
 
-		AccessTransformSet at = AccessTransformSet.create();
-		File jar = getArchiveFile().get().getAsFile();
+	public interface RemapParams extends AbstractRemapParams {
+		ConfigurableFileCollection getNestedJars();
+		ConfigurableFileCollection getRemapClasspath();
+		ConfigurableFileCollection getMixinMappings();
+		ListProperty<Provider<MappingsService>> getMappings();
 
-		try (FileSystemUtil.Delegate fileSystem = FileSystemUtil.getJarFileSystem(jar, false)) {
-			FileSystem fs = fileSystem.get();
-			Path atPath = fs.getPath(Constants.Forge.ACCESS_TRANSFORMER_PATH);
+		Property<Boolean> getUseMixinExtension();
 
-			if (Files.exists(atPath)) {
-				throw new FileAlreadyExistsException("Jar " + jar + " already contains an access transformer - cannot convert AWs!");
-			}
+		record RefmapData(List<String> mixinConfigs, String refmapName) implements Serializable { }
+		ListProperty<RefmapData> getMixinData();
 
-			for (String aw : atAccessWideners) {
-				Path awPath = fs.getPath(aw);
+		Property<JarManifestService> getJarManifestService();
+	}
 
-				if (Files.notExists(awPath)) {
-					throw new NoSuchFileException("Could not find AW '" + aw + "' to convert into AT!");
+	public abstract static class RemapAction extends AbstractRemapAction<RemapParams> {
+		private static final Logger LOGGER = LoggerFactory.getLogger(RemapAction.class);
+
+		private TinyRemapper tinyRemapper;
+
+		@Override
+		public void execute() {
+			try {
+				LOGGER.info("Remapping {} to {}", inputFile, outputFile);
+
+				tinyRemapper = createTinyRemapper();
+
+				remap();
+				remapAccessWidener();
+				addRefmaps();
+				addNestedJars();
+				modifyJarManifest();
+				rewriteJar();
+
+				tinyRemapper.finish();
+				tinyRemapper = null;
+
+				LOGGER.debug("Finished remapping {}", inputFile);
+			} catch (Exception e) {
+				try {
+					Files.deleteIfExists(outputFile);
+				} catch (IOException ex) {
+					LOGGER.error("Failed to delete output file", ex);
 				}
 
-				try (BufferedReader reader = Files.newBufferedReader(awPath, StandardCharsets.UTF_8)) {
-					at.merge(Aw2At.toAccessTransformSet(reader));
-				}
-
-				Files.delete(awPath);
-			}
-
-			LoomGradleExtension extension = LoomGradleExtension.get(getProject());
-			MappingTree mappings = (fromM.get().equals("srg") || toM.get().equals("srg")) && extension.shouldGenerateSrgTiny() ? extension.getMappingsProvider().getMappingsWithSrg() : extension.getMappingsProvider().getMappings();
-
-			try (TinyMappingsReader reader = new TinyMappingsReader(mappings, fromM.get(), toM.get())) {
-				MappingSet mappingSet = reader.read();
-				at = at.remap(mappingSet);
-			}
-
-			try (Writer writer = new LfWriter(Files.newBufferedWriter(atPath))) {
-				AccessTransformFormats.FML.write(writer, at);
+				throw new RuntimeException("Failed to remap", e);
 			}
 		}
-	}
 
-	@InputFile
-	public RegularFileProperty getInput() {
-		return input;
-	}
+		private void remap() throws IOException {
+			final InputTag inputTag = tinyRemapper.createInputTag();
 
-	@Input
-	public Property<Boolean> getAddNestedDependencies() {
-		return addNestedDependencies;
-	}
+			tinyRemapper.readInputsAsync(inputTag, inputFile);
 
-	@Input
-	public Property<Boolean> getAddDefaultNestedDependencies() {
-		return addDefaultNestedDependencies;
-	}
-
-	@Input
-	public Property<Boolean> getRemapAccessWidener() {
-		return remapAccessWidener;
-	}
-
-	/**
-	 * Gets the jar paths to the access wideners that will be converted to ATs for Forge runtime.
-	 * If you specify multiple files, they will be merged into one.
-	 *
-	 * <p>The specified files will be converted and removed from the final jar.
-	 *
-	 * @return the property containing access widener paths in the final jar
-	 */
-	@Input
-	public SetProperty<String> getAtAccessWideners() {
-		return atAccessWideners;
-	}
-
-	public void remapOptions(Action<TinyRemapper.Builder> action) {
-		this.remapOptions.add(action);
-	}
-
-	public RemapJarTask classpath(FileCollection collection) {
-		if (this.classpath == null) {
-			this.classpath = collection;
-		} else {
-			this.classpath = this.classpath.plus(collection);
+			try (OutputConsumerPath outputConsumer = new OutputConsumerPath.Builder(outputFile).build()) {
+				outputConsumer.addNonClassFiles(inputFile);
+				tinyRemapper.apply(outputConsumer, inputTag);
+			}
 		}
 
-		return this;
-	}
+		private void remapAccessWidener() throws IOException {
+			final AccessWidenerFile accessWidenerFile = AccessWidenerFile.fromModJar(inputFile);
 
-	@ApiStatus.Experimental
-	// This only allows mod jars, proceed with care when trying to pass in configurations with projects, or something that depends on a task.
-	public RemapJarTask include(Object... paths) {
-		Collections.addAll(nestedPaths, paths);
-		this.addNestedDependencies.set(true);
+			if (accessWidenerFile == null) {
+				return;
+			}
 
-		return this;
-	}
+			byte[] remapped = remapAccessWidener(accessWidenerFile.content(), tinyRemapper.getEnvironment().getRemapper(), MappingsNamespace.INTERMEDIARY.toString());
 
-	@Input
-	public Property<String> getFromM() {
-		return fromM;
-	}
+			// Finally, replace the output with the remaped aw
+			ZipUtils.replace(outputFile, accessWidenerFile.path(), remapped);
+		}
 
-	@Input
-	public Property<String> getToM() {
-		return toM;
+		private static byte[] remapAccessWidener(byte[] input, Remapper asmRemapper, String targetNamespace) {
+			int version = AccessWidenerReader.readVersion(input);
+
+			AccessWidenerWriter writer = new AccessWidenerWriter(version);
+			AccessWidenerRemapper remapper = new AccessWidenerRemapper(
+					writer,
+					asmRemapper,
+					MappingsNamespace.NAMED.toString(),
+					targetNamespace
+			);
+			AccessWidenerReader reader = new AccessWidenerReader(remapper);
+			reader.read(input);
+
+			return writer.write();
+		}
+
+		private void addNestedJars() {
+			FileCollection nestedJars = getParameters().getNestedJars();
+
+			if (nestedJars.isEmpty()) {
+				LOGGER.info("No jars to nest");
+				return;
+			}
+
+			JarNester.nestJars(nestedJars.getFiles(), outputFile.toFile(), LOGGER);
+		}
+
+		private void modifyJarManifest() throws IOException {
+			int count = ZipUtils.transform(outputFile, Map.of(MANIFEST_PATH, bytes -> {
+				var manifest = new Manifest(new ByteArrayInputStream(bytes));
+
+				getParameters().getJarManifestService().get().apply(manifest);
+				manifest.getMainAttributes().putValue("Fabric-Mapping-Namespace", getParameters().getTargetNamespace().get());
+
+				ByteArrayOutputStream out = new ByteArrayOutputStream();
+				manifest.write(out);
+				return out.toByteArray();
+			}));
+
+			Preconditions.checkState(count > 0, "Did not transform any jar manifest");
+		}
+
+		private void addRefmaps() throws IOException {
+			if (getParameters().getUseMixinExtension().get()) {
+				return;
+			}
+
+			for (RemapParams.RefmapData refmapData : getParameters().getMixinData().get()) {
+				int transformed = ZipUtils.transformJson(JsonObject.class, outputFile, refmapData.mixinConfigs().stream().collect(Collectors.toMap(s -> s, s -> json -> {
+					if (!json.has("refmap")) {
+						json.addProperty("refmap", refmapData.refmapName());
+					}
+
+					return json;
+				})));
+			}
+		}
+
+		private TinyRemapper createTinyRemapper() {
+			TinyRemapper.Builder builder = TinyRemapper.newRemapper();
+
+			for (Provider<MappingsService> provider : getParameters().getMappings().get()) {
+				builder.withMappings(provider.get().getMappingsProvider());
+			}
+
+			for (File mixinMapping : getParameters().getMixinMappings()) {
+				builder.withMappings(TinyUtils.createTinyMappingProvider(mixinMapping.toPath(), getParameters().getSourceNamespace().get(), getParameters().getTargetNamespace().get()));
+			}
+
+			if (getParameters().getUseMixinExtension().get()) {
+				builder.extension(new net.fabricmc.tinyremapper.extension.mixin.MixinExtension());
+			}
+
+			TinyRemapper remapper = builder.build();
+
+			// Apply classpath
+			for (File file : getParameters().getRemapClasspath()) {
+				remapper.readClassPathAsync(file.toPath());
+			}
+
+			return remapper;
+		}
 	}
 }

src/main/java/net/fabricmc/loom/task/RemapSourcesJarTask.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2021 FabricMC
+ * Copyright (c) 2021 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -24,82 +24,65 @@
 
 package net.fabricmc.loom.task;
 
-import org.gradle.api.file.RegularFileProperty;
+import java.io.IOException;
+import java.nio.file.Files;
+
+import javax.inject.Inject;
+
+import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.provider.Property;
-import org.gradle.api.tasks.Input;
-import org.gradle.api.tasks.InputFile;
-import org.gradle.api.tasks.Internal;
-import org.gradle.api.tasks.OutputFile;
 import org.gradle.api.tasks.TaskAction;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
-import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
-import net.fabricmc.loom.util.SourceRemapper;
-
-public class RemapSourcesJarTask extends AbstractLoomTask {
-	private final RegularFileProperty input = getProject().getObjects().fileProperty();
-	private final RegularFileProperty output = getProject().getObjects().fileProperty().convention(input);
-	private final Property<String> sourceNamespace;
-	private final Property<String> targetNamespace;
-	private SourceRemapper sourceRemapper = null;
-	private final Property<Boolean> preserveFileTimestamps = getProject().getObjects().property(Boolean.class).convention(true);
-	private final Property<Boolean> reproducibleFileOrder = getProject().getObjects().property(Boolean.class).convention(false);
+import net.fabricmc.loom.task.service.MappingsService;
+import net.fabricmc.loom.task.service.SourceRemapperService;
 
+public abstract class RemapSourcesJarTask extends AbstractRemapJarTask {
+	@Inject
 	public RemapSourcesJarTask() {
-		this.sourceNamespace = getProject().getObjects().property(String.class).convention("named");
-		this.targetNamespace = getProject().getObjects().property(String.class).convention(SourceRemapper.intermediary(getProject()));
+		super();
+
+		getClasspath().from(getProject().getConfigurations().getByName(JavaPlugin.COMPILE_CLASSPATH_CONFIGURATION_NAME));
 	}
 
 	@TaskAction
-	public void remap() throws Exception {
-		if (sourceRemapper == null) {
-			if (sourceNamespace.get().equals(targetNamespace.get())) {
-				SourceRemapper.remapSources(getProject(), getInput().get().getAsFile(), getOutput().get().getAsFile(),
-						targetNamespace.get().equals(MappingsNamespace.NAMED.toString()) ? SourceRemapper.intermediary(getProject()) : "named", targetNamespace.get(), reproducibleFileOrder.get(), preserveFileTimestamps.get());
-			} else {
-				SourceRemapper.remapSources(getProject(), getInput().get().getAsFile(), getOutput().get().getAsFile(), sourceNamespace.get(), targetNamespace.get(), reproducibleFileOrder.get(), preserveFileTimestamps.get());
+	public void run() {
+		submitWork(RemapSourcesAction.class, params -> {
+			params.getSourcesRemapperService().set(SourceRemapperService.create(getProject(), MappingsService.createDefault(getProject(), getSourceNamespace().get(), getTargetNamespace().get()), getClasspath()));
+		});
+	}
+
+	public interface RemapSourcesParams extends AbstractRemapParams {
+		Property<SourceRemapperService> getSourcesRemapperService();
+	}
+
+	public abstract static class RemapSourcesAction extends AbstractRemapAction<RemapSourcesParams> {
+		private static final Logger LOGGER = LoggerFactory.getLogger(RemapSourcesAction.class);
+
+		private final SourceRemapperService sourceRemapperService;
+
+		public RemapSourcesAction() {
+			super();
+
+			sourceRemapperService = getParameters().getSourcesRemapperService().get();
+		}
+
+		@Override
+		public void execute() {
+			try {
+				sourceRemapperService.remapSourcesJar(inputFile, outputFile);
+
+				rewriteJar();
+			} catch (Exception e) {
+				try {
+					Files.deleteIfExists(outputFile);
+				} catch (IOException ex) {
+					LOGGER.error("Failed to delete output file", ex);
+				}
+
+				throw new RuntimeException("Failed to remap sources", e);
 			}
-		} else {
-			sourceRemapper.scheduleRemapSources(input.get().getAsFile(), output.get().getAsFile(), reproducibleFileOrder.get(), preserveFileTimestamps.get());
 		}
 	}
-
-	@Internal
-	public SourceRemapper getSourceRemapper() {
-		return sourceRemapper;
-	}
-
-	public RemapSourcesJarTask setSourceRemapper(SourceRemapper sourceRemapper) {
-		this.sourceRemapper = sourceRemapper;
-		return this;
-	}
-
-	@InputFile
-	public RegularFileProperty getInput() {
-		return input;
-	}
-
-	@OutputFile
-	public RegularFileProperty getOutput() {
-		return output;
-	}
-
-	@Input
-	public Property<String> getSourceNamespace() {
-		return sourceNamespace;
-	}
-
-	@Input
-	public Property<String> getTargetNamespace() {
-		return targetNamespace;
-	}
-
-	@Input
-	public Property<Boolean> getPreserveFileTimestamps() {
-		return preserveFileTimestamps;
-	}
-
-	@Input
-	public Property<Boolean> getReproducibleFileOrder() {
-		return reproducibleFileOrder;
-	}
 }

src/main/java/net/fabricmc/loom/task/RemapTaskConfiguration.java

@@ -0,0 +1,138 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2016-2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task;
+
+import java.io.File;
+
+import org.gradle.api.Project;
+import org.gradle.api.Task;
+import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.plugins.BasePlugin;
+import org.gradle.api.plugins.JavaPlugin;
+import org.gradle.api.plugins.JavaPluginExtension;
+import org.gradle.api.tasks.SourceSet;
+import org.gradle.api.tasks.TaskContainer;
+import org.gradle.api.tasks.TaskProvider;
+import org.gradle.api.tasks.bundling.AbstractArchiveTask;
+import org.gradle.api.tasks.bundling.Jar;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.util.Constants;
+
+public class RemapTaskConfiguration {
+	public static final String REMAP_JAR_TASK_NAME = "remapJar";
+	public static final String REMAP_SOURCES_JAR_TASK_NAME = "remapSourcesJar";
+
+	public static void setupRemap(Project project) {
+		final TaskContainer tasks = project.getTasks();
+		final LoomGradleExtension extension = LoomGradleExtension.get(project);
+
+		if (!extension.getRemapArchives().get()) {
+			extension.getUnmappedModCollection().from(project.getTasks().getByName(JavaPlugin.JAR_TASK_NAME));
+			return;
+		}
+
+		// Register the default remap jar task
+		TaskProvider<RemapJarTask> remapJarTaskProvider = tasks.register(REMAP_JAR_TASK_NAME, RemapJarTask.class, task -> {
+			final AbstractArchiveTask jarTask = tasks.named(JavaPlugin.JAR_TASK_NAME, AbstractArchiveTask.class).get();
+
+			// Basic task setup
+			task.dependsOn(jarTask);
+			task.setDescription("Remaps the built project jar to intermediary mappings.");
+			task.setGroup(Constants.TaskGroup.FABRIC);
+			project.getArtifacts().add(JavaPlugin.API_ELEMENTS_CONFIGURATION_NAME, task);
+			project.getArtifacts().add(JavaPlugin.RUNTIME_ELEMENTS_CONFIGURATION_NAME, task);
+
+			// Setup the input file and the nested deps
+			task.getInputFile().convention(jarTask.getArchiveFile());
+			task.dependsOn(tasks.named(JavaPlugin.JAR_TASK_NAME));
+		});
+
+		// Configure the default jar task
+		tasks.named(JavaPlugin.JAR_TASK_NAME, AbstractArchiveTask.class).configure(task -> {
+			task.getArchiveClassifier().convention("dev");
+			task.getDestinationDirectory().set(new File(project.getBuildDir(), "devlibs"));
+		});
+
+		tasks.named(BasePlugin.ASSEMBLE_TASK_NAME).configure(task -> task.dependsOn(remapJarTaskProvider));
+
+		trySetupSourceRemapping(project);
+
+		if (extension.getSetupRemappedVariants().get()) {
+			// Remove -dev jars from the default jar task
+			for (String configurationName : new String[] { JavaPlugin.API_ELEMENTS_CONFIGURATION_NAME, JavaPlugin.RUNTIME_ELEMENTS_CONFIGURATION_NAME }) {
+				Configuration configuration = project.getConfigurations().getByName(configurationName);
+				configuration.getArtifacts().removeIf(artifact -> {
+					Task jarTask = project.getTasks().getByName(JavaPlugin.JAR_TASK_NAME);
+					// if the artifact is a -dev jar and "builtBy jar"
+					return "dev".equals(artifact.getClassifier()) && artifact.getBuildDependencies().getDependencies(null).contains(jarTask);
+				});
+			}
+		}
+	}
+
+	private static void trySetupSourceRemapping(Project project) {
+		final TaskContainer tasks = project.getTasks();
+		final LoomGradleExtension extension = LoomGradleExtension.get(project);
+
+		TaskProvider<RemapSourcesJarTask> remapSourcesTask = tasks.register(REMAP_SOURCES_JAR_TASK_NAME, RemapSourcesJarTask.class, task -> {
+			task.setDescription("Remaps the default sources jar to intermediary mappings.");
+			task.setGroup(Constants.TaskGroup.FABRIC);
+
+			final JavaPluginExtension javaExtension = project.getExtensions().getByType(JavaPluginExtension.class);
+			final String sourcesJarTaskName = javaExtension.getSourceSets().getByName(SourceSet.MAIN_SOURCE_SET_NAME).getSourcesJarTaskName();
+			final Task sourcesTask = project.getTasks().findByName(sourcesJarTaskName);
+
+			if (sourcesTask == null) {
+				project.getLogger().info("{} task was not found, not remapping sources", sourcesJarTaskName);
+				task.setEnabled(false);
+				return;
+			}
+
+			if (!(sourcesTask instanceof Jar sourcesJarTask)) {
+				project.getLogger().info("{} task is not a Jar task, not remapping sources", sourcesJarTaskName);
+				task.setEnabled(false);
+				return;
+			}
+
+			sourcesJarTask.getArchiveClassifier().convention("dev-sources");
+			sourcesJarTask.getDestinationDirectory().set(new File(project.getBuildDir(), "devlibs"));
+			task.getArchiveClassifier().convention("sources");
+
+			task.dependsOn(sourcesJarTask);
+			task.getInputFile().convention(sourcesJarTask.getArchiveFile());
+
+			if (extension.getSetupRemappedVariants().get()) {
+				project.getArtifacts().add(JavaPlugin.SOURCES_ELEMENTS_CONFIGURATION_NAME, task);
+
+				// Remove the dev sources artifact
+				Configuration configuration = project.getConfigurations().getByName(JavaPlugin.SOURCES_ELEMENTS_CONFIGURATION_NAME);
+				configuration.getArtifacts().removeIf(a -> a.getFile().equals(sourcesJarTask.getArchiveFile().get().getAsFile()));
+			}
+		});
+
+		tasks.named(BasePlugin.ASSEMBLE_TASK_NAME).configure(task -> task.dependsOn(remapSourcesTask));
+	}
+}

src/main/java/net/fabricmc/loom/task/ValidateAccessWidenerTask.java

@@ -59,6 +59,9 @@ public abstract class ValidateAccessWidenerTask extends DefaultTask {
 
 		getAccessWidener().convention(extension.getAccessWidenerPath()).finalizeValueOnRead();
 		getTargetJar().convention(getProject().getObjects().fileProperty().fileValue(extension.getMinecraftMappedProvider().getMappedJar())).finalizeValueOnRead();
+
+		// Ignore outputs for up-to-date checks as there aren't any (so only inputs are checked)
+		getOutputs().upToDateWhen(task -> true);
 	}
 
 	@TaskAction

src/main/java/net/fabricmc/loom/task/service/JarManifestService.java

@@ -0,0 +1,123 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task.service;
+
+import java.io.Serializable;
+import java.util.Optional;
+import java.util.jar.Attributes;
+import java.util.jar.Manifest;
+
+import org.gradle.api.Project;
+import org.gradle.api.artifacts.Dependency;
+import org.gradle.api.provider.Property;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.services.BuildService;
+import org.gradle.api.services.BuildServiceParameters;
+import org.gradle.util.GradleVersion;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.LoomGradlePlugin;
+import net.fabricmc.loom.util.Constants;
+import net.fabricmc.tinyremapper.TinyRemapper;
+
+public abstract class JarManifestService implements BuildService<JarManifestService.Params> {
+	interface Params extends BuildServiceParameters {
+		Property<String> getGradleVersion();
+		Property<String> getLoomVersion();
+		Property<String> getMCEVersion();
+		Property<String> getMinecraftVersion();
+		Property<String> getTinyRemapperVersion();
+		Property<String> getFabricLoaderVersion();
+		Property<MixinVersion> getMixinVersion();
+	}
+
+	public static Provider<JarManifestService> get(Project project) {
+		return project.getGradle().getSharedServices().registerIfAbsent("LoomJarManifestService:" + project.getName(), JarManifestService.class, spec -> {
+			spec.parameters(params -> {
+				LoomGradleExtension extension = LoomGradleExtension.get(project);
+				Optional<String> tinyRemapperVersion = Optional.ofNullable(TinyRemapper.class.getPackage().getImplementationVersion());
+
+				params.getGradleVersion().set(GradleVersion.current().getVersion());
+				params.getLoomVersion().set(LoomGradlePlugin.LOOM_VERSION);
+				params.getMCEVersion().set(Constants.Dependencies.Versions.MIXIN_COMPILE_EXTENSIONS);
+				params.getMinecraftVersion().set(extension.getMinecraftProvider().minecraftVersion());
+				params.getTinyRemapperVersion().set(tinyRemapperVersion.orElse("unknown"));
+				params.getFabricLoaderVersion().set(getLoaderVersion(project).orElse("unknown"));
+				params.getMixinVersion().set(getMixinVersion(project).orElse(new MixinVersion("unknown", "unknown")));
+			});
+		});
+	}
+
+	public void apply(Manifest manifest) {
+		// Don't set when running the reproducible build tests as it will break them when anything updates
+		if (Boolean.getBoolean("loom.test.reproducible")) {
+			return;
+		}
+
+		Attributes attributes = manifest.getMainAttributes();
+		Params p = getParameters();
+
+		attributes.putValue("Fabric-Gradle-Version", p.getGradleVersion().get());
+		attributes.putValue("Fabric-Loom-Version", p.getLoomVersion().get());
+		attributes.putValue("Fabric-Mixin-Compile-Extensions-Version", p.getMCEVersion().get());
+		attributes.putValue("Fabric-Minecraft-Version", p.getMinecraftVersion().get());
+		attributes.putValue("Fabric-Tiny-Remapper-Version", p.getTinyRemapperVersion().get());
+		attributes.putValue("Fabric-Loader-Version", p.getFabricLoaderVersion().get());
+
+		// This can be overridden by mods if required
+		if (!attributes.containsKey("Fabric-Mixin-Version")) {
+			attributes.putValue("Fabric-Mixin-Version", p.getMixinVersion().get().version());
+			attributes.putValue("Fabric-Mixin-Group", p.getMixinVersion().get().group());
+		}
+	}
+
+	private static Optional<String> getLoaderVersion(Project project) {
+		LoomGradleExtension extension = LoomGradleExtension.get(project);
+
+		if (extension.getInstallerData() == null) {
+			project.getLogger().warn("Could not determine fabric loader version for jar manifest");
+			return Optional.empty();
+		}
+
+		return Optional.of(extension.getInstallerData().version());
+	}
+
+	private record MixinVersion(String group, String version) implements Serializable { }
+
+	private static Optional<MixinVersion> getMixinVersion(Project project) {
+		// Not super ideal that this uses the mod compile classpath, should prob look into making this not a thing at somepoint
+		Optional<Dependency> dependency = project.getConfigurations().getByName(Constants.Configurations.LOADER_DEPENDENCIES)
+				.getDependencies()
+				.stream()
+				.filter(dep -> "sponge-mixin".equals(dep.getName()))
+				.findFirst();
+
+		if (dependency.isEmpty()) {
+			project.getLogger().warn("Could not determine Mixin version for jar manifest");
+		}
+
+		return dependency.map(d -> new MixinVersion(d.getGroup(), d.getVersion()));
+	}
+}

src/main/java/net/fabricmc/loom/task/service/MappingsService.java

@@ -0,0 +1,118 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task.service;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+
+import org.gradle.api.Project;
+import org.gradle.api.file.RegularFileProperty;
+import org.gradle.api.provider.Property;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.services.BuildService;
+import org.gradle.api.services.BuildServiceParameters;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
+import net.fabricmc.loom.util.TinyRemapperHelper;
+import net.fabricmc.mappingio.MappingReader;
+import net.fabricmc.mappingio.tree.MemoryMappingTree;
+import net.fabricmc.tinyremapper.IMappingProvider;
+
+public abstract class MappingsService implements BuildService<MappingsService.Params>, AutoCloseable {
+	interface Params extends BuildServiceParameters {
+		RegularFileProperty getMappingsFile();
+
+		Property<String> getFromNamespace();
+		Property<String> getToNamespace();
+
+		Property<Boolean> getRemapLocals();
+	}
+
+	public static synchronized Provider<MappingsService> create(Project project, String name, File mappingsFile, String from, String to, boolean remapLocals) {
+		return project.getGradle().getSharedServices().registerIfAbsent(name, MappingsService.class, spec -> {
+			spec.parameters(params -> {
+				params.getMappingsFile().set(mappingsFile);
+				params.getFromNamespace().set(from);
+				params.getToNamespace().set(to);
+				params.getRemapLocals().set(remapLocals);
+			});
+		});
+	}
+
+	public static Provider<MappingsService> createDefault(Project project, String from, String to) {
+		final MappingsProviderImpl mappingsProvider = LoomGradleExtension.get(project).getMappingsProvider();
+		final String name = mappingsProvider.getBuildServiceName("mappingsProvider", from, to);
+		return MappingsService.create(project, name, mappingsProvider.tinyMappings.toFile(), from, to, false);
+	}
+
+	private IMappingProvider mappingProvider = null;
+	private MemoryMappingTree memoryMappingTree = null;
+
+	public synchronized IMappingProvider getMappingsProvider() {
+		if (mappingProvider == null) {
+			try {
+				mappingProvider = TinyRemapperHelper.create(
+						getParameters().getMappingsFile().get().getAsFile().toPath(),
+						getParameters().getFromNamespace().get(),
+						getParameters().getToNamespace().get(),
+						getParameters().getRemapLocals().get()
+				);
+			} catch (IOException e) {
+				throw new UncheckedIOException("Failed to read mappings from: " + getParameters().getMappingsFile().get().getAsFile().getAbsolutePath(), e);
+			}
+		}
+
+		return mappingProvider;
+	}
+
+	public synchronized MemoryMappingTree getMemoryMappingTree() {
+		if (memoryMappingTree == null) {
+			memoryMappingTree = new MemoryMappingTree();
+
+			try {
+				MappingReader.read(getParameters().getMappingsFile().get().getAsFile().toPath(), memoryMappingTree);
+			} catch (IOException e) {
+				throw new UncheckedIOException("Failed to read mappings from: " + getParameters().getMappingsFile().get().getAsFile().getAbsolutePath(), e);
+			}
+		}
+
+		return memoryMappingTree;
+	}
+
+	public String getFromNamespace() {
+		return getParameters().getFromNamespace().get();
+	}
+
+	public String getToNamespace() {
+		return getParameters().getToNamespace().get();
+	}
+
+	@Override
+	public void close() {
+		mappingProvider = null;
+	}
+}

src/main/java/net/fabricmc/loom/task/service/SourceRemapperService.java

@@ -0,0 +1,133 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.task.service;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.cadixdev.lorenz.MappingSet;
+import org.cadixdev.mercury.Mercury;
+import org.cadixdev.mercury.remapper.MercuryRemapper;
+import org.gradle.api.Project;
+import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.file.FileCollection;
+import org.gradle.api.provider.Property;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.services.BuildService;
+import org.gradle.api.services.BuildServiceParameters;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import net.fabricmc.loom.util.DeletingFileVisitor;
+import net.fabricmc.loom.util.FileSystemUtil;
+import net.fabricmc.loom.util.SourceRemapper;
+import net.fabricmc.loom.util.ZipUtils;
+import net.fabricmc.lorenztiny.TinyMappingsReader;
+
+public abstract class SourceRemapperService implements BuildService<SourceRemapperService.Params>, AutoCloseable {
+	public interface Params extends BuildServiceParameters {
+		Property<Provider<MappingsService>> getMappings();
+
+		ConfigurableFileCollection getClasspath();
+	}
+
+	public static synchronized Provider<SourceRemapperService> create(Project project, Provider<MappingsService> mappings, FileCollection classpath) {
+		// TODO may need a better name, im not too sure
+		return project.getGradle().getSharedServices().registerIfAbsent("sourceremapper", SourceRemapperService.class, spec ->
+			spec.parameters(params -> {
+				params.getMappings().set(mappings);
+				params.getClasspath().from(classpath);
+			}
+		));
+	}
+
+	private static final Logger LOGGER = LoggerFactory.getLogger(SourceRemapperService.class);
+
+	private Mercury mercury;
+
+	public void remapSourcesJar(Path source, Path destination) throws IOException {
+		if (source.equals(destination)) {
+			throw new UnsupportedOperationException("Cannot remap in place");
+		}
+
+		Path srcPath = source;
+		boolean isSrcTmp = false;
+
+		// Create a temp directory with all of the sources
+		if (!Files.isDirectory(source)) {
+			isSrcTmp = true;
+			srcPath = Files.createTempDirectory("fabric-loom-src");
+			ZipUtils.unpackAll(source, srcPath);
+		}
+
+		if (!Files.isDirectory(destination) && Files.exists(destination)) {
+			Files.delete(destination);
+		}
+
+		try (FileSystemUtil.Delegate dstFs = Files.isDirectory(destination) ? null : FileSystemUtil.getJarFileSystem(destination, true)) {
+			Path dstPath = dstFs != null ? dstFs.get().getPath("/") : destination;
+
+			doRemap(srcPath, dstPath, source);
+			SourceRemapper.copyNonJavaFiles(srcPath, dstPath, LOGGER, source);
+		} finally {
+			if (isSrcTmp) {
+				Files.walkFileTree(srcPath, new DeletingFileVisitor());
+			}
+		}
+	}
+
+	private synchronized void doRemap(Path srcPath, Path dstPath, Path source) throws IOException {
+		if (mercury == null) {
+			mercury = new Mercury();
+			mercury.setGracefulClasspathChecks(true);
+			mercury.getProcessors().add(MercuryRemapper.create(getMappings()));
+
+			getParameters().getClasspath().forEach(file -> mercury.getClassPath().add(file.toPath()));
+		}
+
+		try {
+			// Not thread safe!!
+			mercury.rewrite(srcPath, dstPath);
+		} catch (Exception e) {
+			LOGGER.warn("Could not remap " + source + " fully!", e);
+		}
+	}
+
+	private MappingSet getMappings() throws IOException {
+		return new TinyMappingsReader(mappingsService().getMemoryMappingTree(), mappingsService().getFromNamespace(), mappingsService().getToNamespace()).read();
+	}
+
+	private MappingsService mappingsService() {
+		return getParameters().getMappings().get().get();
+	}
+
+	@Override
+	public void close() throws Exception {
+		mercury = null;
+		// This is required (:
+		System.gc();
+	}
+}

src/main/java/net/fabricmc/loom/util/Architecture.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2021 FabricMC
+ * Copyright (c) 2021 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -22,19 +22,26 @@
  * SOFTWARE.
  */
 
-package net.fabricmc.loom.build.nesting;
+package net.fabricmc.loom.util;
 
-import java.io.File;
-import java.util.Collection;
+public class Architecture {
+	public static final Architecture CURRENT = new Architecture(System.getProperty("os.arch"));
 
-import org.gradle.api.Project;
-import org.jetbrains.annotations.ApiStatus;
+	private final String name;
 
-@ApiStatus.Internal
-public interface NestedJarProvider {
-	// provide all the files to be included, they should already be resolved but can be transformed here
-	Collection<File> provide();
+	public Architecture(String name) {
+		this.name = name;
+	}
 
-	// Setup the files ready to be provided
-	default void prepare(Project project) { }
+	public boolean is64Bit() {
+		return name.contains("64") || name.startsWith("armv8");
+	}
+
+	public boolean isArm() {
+		return name.startsWith("arm") || name.startsWith("aarch64");
+	}
+
+	public String getName() {
+		return name;
+	}
 }

src/main/java/net/fabricmc/loom/util/ClosureAction.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2020 FabricMC
+ * Copyright (c) 2021 FabricMC
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -22,17 +22,15 @@
  * SOFTWARE.
  */
 
-package net.fabricmc.loom.task;
+package net.fabricmc.loom.util;
 
-import org.gradle.api.tasks.Internal;
+import groovy.lang.Closure;
+import org.gradle.api.Action;
 
-import net.fabricmc.loom.util.SourceRemapper;
-
-public class RemapAllSourcesTask extends AbstractLoomTask {
-	public SourceRemapper sourceRemapper;
-
-	@Internal
-	public SourceRemapper getSourceRemapper() {
-		return sourceRemapper;
+public record ClosureAction<T>(Closure closure) implements Action<T> {
+	@Override
+	public void execute(T t) {
+		closure.setDelegate(t);
+		closure.call(t);
 	}
 }

src/main/java/net/fabricmc/loom/util/Constants.java

@@ -41,8 +41,6 @@ public class Constants {
 	public static final String EXPERIMENTAL_VERSIONS = "https://maven.fabricmc.net/net/minecraft/experimental_versions.json";
 	public static final String FABRIC_REPOSITORY = "https://maven.fabricmc.net/";
 
-	public static final String SYSTEM_ARCH = System.getProperty("os.arch").equals("64") ? "64" : "32";
-
 	public static final int ASM_VERSION = Opcodes.ASM9;
 
 	public static final List<RemappedConfigurationEntry> MOD_COMPILE_ENTRIES = ImmutableList.of(
@@ -65,8 +63,13 @@ public class Constants {
 		public static final String MOD_COMPILE_CLASSPATH_MAPPED = "modCompileClasspathMapped";
 		public static final String INCLUDE = "include";
 		public static final String MINECRAFT = "minecraft";
+		/**
+		 * The server specific configuration will be empty when using a legacy (pre 21w38a server jar)
+		 * find the client only dependencies on the "minecraftLibraries" config.
+		 */
+		public static final String MINECRAFT_SERVER_DEPENDENCIES = "minecraftServerLibraries";
 		public static final String MINECRAFT_DEPENDENCIES = "minecraftLibraries";
-		public static final String MINECRAFT_REMAP_CLASSPATH = "minecraftRemapClasspath";
+		public static final String MINECRAFT_NATIVES = "minecraftNatives";
 		public static final String MINECRAFT_NAMED = "minecraftNamed";
 		public static final String MAPPINGS = "mappings";
 		public static final String MAPPINGS_FINAL = "mappingsFinal";
@@ -118,6 +121,7 @@ public class Constants {
 		public static final String DEV_LAUNCH_INJECTOR = "net.fabricmc:dev-launch-injector:";
 		public static final String TERMINAL_CONSOLE_APPENDER = "net.minecrell:terminalconsoleappender:";
 		public static final String JETBRAINS_ANNOTATIONS = "org.jetbrains:annotations:";
+		public static final String NATIVE_SUPPORT = "net.fabricmc:fabric-loom-native-support:";
 		public static final String JAVAX_ANNOTATIONS = "com.google.code.findbugs:jsr305:"; // I hate that I have to add these.
 		public static final String FORGE_RUNTIME = "dev.architectury:architectury-loom-runtime:";
 		public static final String ACCESS_TRANSFORMERS = "net.minecraftforge:accesstransformers:";
@@ -133,6 +137,7 @@ public class Constants {
 			public static final String DEV_LAUNCH_INJECTOR = "0.2.1+build.8";
 			public static final String TERMINAL_CONSOLE_APPENDER = "1.2.0";
 			public static final String JETBRAINS_ANNOTATIONS = "23.0.0";
+			public static final String NATIVE_SUPPORT_VERSION = "1.0.1";
 			public static final String JAVAX_ANNOTATIONS = "3.0.2";
 			public static final String FORGE_RUNTIME = "1.1.3";
 			public static final String ACCESS_TRANSFORMERS = "3.0.1";

src/main/java/net/fabricmc/loom/util/FileSystemUtil.java

@@ -28,9 +28,12 @@ import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.FileSystem;
 import java.nio.file.FileSystemAlreadyExistsException;
 import java.nio.file.FileSystems;
+import java.nio.file.Files;
+import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
 import java.util.Collections;
 import java.util.Map;
@@ -38,6 +41,20 @@ import java.util.function.Supplier;
 
 public final class FileSystemUtil {
 	public record Delegate(FileSystem fs, boolean owner) implements AutoCloseable, Supplier<FileSystem> {
+		public byte[] readAllBytes(String path) throws IOException {
+			Path fsPath = get().getPath(path);
+
+			if (Files.exists(fsPath)) {
+				return Files.readAllBytes(fsPath);
+			} else {
+				throw new NoSuchFileException(fsPath.toString());
+			}
+		}
+
+		public String readString(String path) throws IOException {
+			return new String(readAllBytes(path), StandardCharsets.UTF_8);
+		}
+
 		@Override
 		public void close() throws IOException {
 			if (owner) {
@@ -65,6 +82,10 @@ public final class FileSystemUtil {
 		return getJarFileSystem(path.toUri(), create);
 	}
 
+	public static Delegate getJarFileSystem(Path path) throws IOException {
+		return getJarFileSystem(path, false);
+	}
+
 	public static Delegate getJarFileSystem(URI uri, boolean create) throws IOException {
 		URI jarUri;
 

src/main/java/net/fabricmc/loom/util/ModUtils.java

@@ -25,18 +25,12 @@
 package net.fabricmc.loom.util;
 
 import java.io.File;
-import java.io.IOException;
-import java.util.zip.ZipFile;
 
 public final class ModUtils {
 	private ModUtils() {
 	}
 
 	public static boolean isMod(File input) {
-		try (ZipFile zipFile = new ZipFile(input)) {
-			return zipFile.getEntry("fabric.mod.json") != null;
-		} catch (IOException e) {
-			return false;
-		}
+		return ZipUtils.contains(input.toPath(), "fabric.mod.json");
 	}
 }

src/main/java/net/fabricmc/loom/util/OperatingSystem.java

@@ -30,23 +30,21 @@ import java.net.StandardProtocolFamily;
 import java.nio.channels.ServerSocketChannel;
 
 public class OperatingSystem {
-	public static String getOS() {
+	public static final String WINDOWS = "windows";
+	public static final String MAC_OS = "osx";
+	public static final String LINUX = "linux";
+
+	public static final String CURRENT_OS = getOS();
+
+	private static String getOS() {
 		String osName = System.getProperty("os.name").toLowerCase();
 
 		if (osName.contains("win")) {
-			return "windows";
+			return WINDOWS;
 		} else if (osName.contains("mac")) {
-			return "osx";
+			return MAC_OS;
 		} else {
-			return "linux";
-		}
-	}
-
-	public static String getArch() {
-		if (is64Bit()) {
-			return "64";
-		} else {
-			return "32";
+			return LINUX;
 		}
 	}
 
@@ -54,10 +52,6 @@ public class OperatingSystem {
 		return System.getProperty("sun.arch.data.model").contains("64");
 	}
 
-	public static boolean isWindows() {
-		return getOS().equals("windows");
-	}
-
 	public static boolean isCIBuild() {
 		String loomProperty = System.getProperty("fabric.loom.ci");
 

src/main/java/net/fabricmc/loom/util/SourceRemapper.java

@@ -37,6 +37,7 @@ import org.cadixdev.lorenz.MappingSet;
 import org.cadixdev.mercury.Mercury;
 import org.cadixdev.mercury.remapper.MercuryRemapper;
 import org.gradle.api.Project;
+import org.slf4j.Logger;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.configuration.RemappedConfigurationEntry;
@@ -152,7 +153,7 @@ public class SourceRemapper {
 			project.getLogger().warn("Could not remap " + source.getName() + " fully!", e);
 		}
 
-		copyNonJavaFiles(srcPath, dstPath, project, source);
+		copyNonJavaFiles(srcPath, dstPath, project.getLogger(), source.toPath());
 
 		if (dstFs != null) {
 			dstFs.close();
@@ -231,7 +232,7 @@ public class SourceRemapper {
 		return mercury;
 	}
 
-	private static void copyNonJavaFiles(Path from, Path to, Project project, File source) throws IOException {
+	public static void copyNonJavaFiles(Path from, Path to, Logger logger, Path source) throws IOException {
 		Files.walk(from).forEach(path -> {
 			Path targetPath = to.resolve(from.relativize(path).toString());
 
@@ -239,7 +240,7 @@ public class SourceRemapper {
 				try {
 					Files.copy(path, targetPath);
 				} catch (IOException e) {
-					project.getLogger().warn("Could not copy non-java sources '" + source.getName() + "' fully!", e);
+					logger.warn("Could not copy non-java sources '" + source + "' fully!", e);
 				}
 			}
 		});

src/main/java/net/fabricmc/loom/util/TinyRemapperHelper.java

@@ -44,6 +44,7 @@ import org.gradle.api.Project;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
+import net.fabricmc.mappingio.MappingReader;
 import net.fabricmc.mappingio.tree.MappingTree;
 import net.fabricmc.mappingio.tree.MemoryMappingTree;
 
@@ -138,6 +139,12 @@ public final class TinyRemapperHelper {
 		return new IMappingProvider.Member(className, memberName, descriptor);
 	}
 
+	public static IMappingProvider create(Path mappings, String from, String to, boolean remapLocalVariables) throws IOException {
+		MemoryMappingTree mappingTree = new MemoryMappingTree();
+		MappingReader.read(mappings, mappingTree);
+		return create(mappingTree, from, to, remapLocalVariables);
+	}
+
 	public static IMappingProvider create(MappingTree mappings, String from, String to, boolean remapLocalVariables) {
 		return (acceptor) -> {
 			for (MappingTree.ClassMapping classDef : mappings.getClasses()) {

src/main/java/net/fabricmc/loom/util/ZipUtils.java

@@ -83,13 +83,7 @@ public class ZipUtils {
 
 	public static byte[] unpack(Path zip, String path) throws IOException {
 		try (FileSystemUtil.Delegate fs = FileSystemUtil.getJarFileSystem(zip, false)) {
-			Path fsPath = fs.get().getPath(path);
-
-			if (Files.exists(fsPath)) {
-				return Files.readAllBytes(fsPath);
-			} else {
-				throw new NoSuchFileException(fsPath.toString());
-			}
+			return fs.readAllBytes(path);
 		}
 	}
 

src/test/groovy/net/fabricmc/loom/test/LoomTestConstants.groovy

@@ -28,7 +28,7 @@ import org.gradle.util.GradleVersion
 
 class LoomTestConstants {
     public final static String DEFAULT_GRADLE = GradleVersion.current().getVersion()
-    public final static String PRE_RELEASE_GRADLE = "7.4-20211203231050+0000"
+    public final static String PRE_RELEASE_GRADLE = "7.5-20211228231407+0000"
 
     public final static String[] STANDARD_TEST_VERSIONS = [DEFAULT_GRADLE, PRE_RELEASE_GRADLE]
 }

src/test/groovy/net/fabricmc/loom/test/integration/FabricAPITest.groovy

@@ -44,7 +44,7 @@ class FabricAPITest extends Specification implements GradleProjectTestTrait {
 		setup:
 			def gradle = gradleProject(
 					repo: "https://github.com/FabricMC/fabric.git",
-					commit: "ce6198f63bbe0e17ba631420e9186fb72cc8b2af",
+					commit: "71b634e5b7845296b11be3fa6545f4fbfacc017f",
 					version: version,
 					patch: "fabric_api"
 			)

src/test/groovy/net/fabricmc/loom/test/integration/InterfaceInjectionTest.groovy

@@ -22,34 +22,30 @@
  * SOFTWARE.
  */
 
-package net.fabricmc.loom.test.unit
+package net.fabricmc.loom.test.integration
 
-import net.fabricmc.loom.build.nesting.MergedNestedJarProvider
-import net.fabricmc.loom.build.nesting.NestedJarProvider
-import org.gradle.api.Project
+import net.fabricmc.loom.test.util.GradleProjectTestTrait
+import net.fabricmc.loom.util.ZipUtils
 import spock.lang.Specification
+import spock.lang.Unroll
 
-class MergedNestedJarProviderTest extends Specification {
-    def "empty test"() {
-        given:
-            def nestedJarProvider = new MergedNestedJarProvider(new TestNestedJarProvider())
-        when:
-            nestedJarProvider.prepare(null)
-        then:
-            nestedJarProvider.provide() != null
-    }
+import static net.fabricmc.loom.test.LoomTestConstants.STANDARD_TEST_VERSIONS
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS
 
-    private class TestNestedJarProvider implements NestedJarProvider {
-        private Collection<File> files = null
+class InterfaceInjectionTest extends Specification implements GradleProjectTestTrait {
+	@Unroll
+	def "interface injection (gradle #version)"() {
+		setup:
+			def gradle = gradleProject(project: "interfaceInjection", version: version)
+			ZipUtils.pack(new File(gradle.projectDir, "dummyDependency").toPath(), new File(gradle.projectDir, "dummy.jar").toPath())
 
-        @Override
-        Collection<File> provide() {
-            return files
-        }
+		when:
+			def result = gradle.run(task: "build")
 
-        @Override
-        void prepare(Project project) {
-            files = []
-        }
-    }
+		then:
+			result.task(":build").outcome == SUCCESS
+
+		where:
+			version << STANDARD_TEST_VERSIONS
+	}
 }

src/test/groovy/net/fabricmc/loom/test/integration/MixinApAutoRefmapTest.groovy

@@ -67,6 +67,9 @@ class MixinApAutoRefmapTest extends Specification implements GradleProjectTestTr
             def j5 = JsonParser.parseReader(new InputStreamReader(jar.getInputStream(jar.getEntry("irrelevant.mixins.json"))))
             !j5.asJsonObject.has("refmap")
 
+            def j6 = JsonParser.parseReader(new InputStreamReader(jar.getInputStream(jar.getEntry("subfolder/subfolder.mixins.json"))))
+            j6.asJsonObject.getAsJsonPrimitive("refmap").getAsString() == "refmap0001.json"
+
         where:
             version << STANDARD_TEST_VERSIONS
     }

src/test/groovy/net/fabricmc/loom/test/integration/MixinApSimpleTest.groovy

@@ -47,7 +47,7 @@ class MixinApSimpleTest extends Specification implements GradleProjectTestTrait
             result.task(":build").outcome == SUCCESS
 
             // verify the ref-map name is correctly generated
-            def main = new JarFile(gradle.getOutputFile("fabric-example-mod-1.0.0-dev.jar").absoluteFile)
+            def main = new JarFile(new File(gradle.projectDir, "build/devlibs/fabric-example-mod-1.0.0-dev.jar").absoluteFile)
             main.getEntry("main-refmap0000.json") != null
             def mixin = new JarFile(gradle.getOutputFile("fabric-example-mod-1.0.0-mixin.jar").absoluteFile)
             mixin.getEntry("default-refmap0000.json") != null

src/test/groovy/net/fabricmc/loom/test/integration/MultiProjectTest.groovy

@@ -45,9 +45,6 @@ class MultiProjectTest extends Specification implements GradleProjectTestTrait {
 			result.task(":core:build").outcome == SUCCESS
 			result.task(":example:build").outcome == SUCCESS
 
-			result.task(":remapAllJars").outcome == SUCCESS
-			result.task(":remapAllSources").outcome == SUCCESS
-
 			gradle.hasOutputZipEntry("multiproject-1.0.0.jar", "META-INF/jars/example-1.0.0.jar")
 			gradle.hasOutputZipEntry("multiproject-1.0.0.jar", "META-INF/jars/core-1.0.0.jar")
 			gradle.hasOutputZipEntry("multiproject-1.0.0.jar", "META-INF/jars/fabric-api-base-0.2.1+9354966b7d.jar")

src/test/groovy/net/fabricmc/loom/test/integration/NativesTest.groovy

@@ -0,0 +1,86 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.test.integration
+
+import net.fabricmc.loom.test.util.GradleProjectTestTrait
+import spock.lang.Specification
+import spock.lang.Unroll
+import spock.util.environment.RestoreSystemProperties
+
+import static net.fabricmc.loom.test.LoomTestConstants.STANDARD_TEST_VERSIONS
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS
+import static org.gradle.testkit.runner.TaskOutcome.UP_TO_DATE
+
+class NativesTest extends Specification implements GradleProjectTestTrait  {
+    @Unroll
+    def "Default natives for 1.18 (gradle #version)"() {
+        setup:
+            def gradle = gradleProject(project: "minimalBase", version: version)
+
+            gradle.buildGradle << '''
+                    dependencies {
+                        minecraft "com.mojang:minecraft:1.18"
+                        mappings loom.officialMojangMappings()
+                    }
+                '''
+
+        when:
+            // Run the task twice to ensure its up to date
+            def result = gradle.run(task: "extractNatives")
+            def result2 = gradle.run(task: "extractNatives")
+
+        then:
+            result.task(":extractNatives").outcome == SUCCESS
+            result2.task(":extractNatives").outcome == UP_TO_DATE
+
+        where:
+            version << STANDARD_TEST_VERSIONS
+    }
+
+    @RestoreSystemProperties
+    @Unroll
+    def "Overridden natives for 1.18 (gradle #version)"() {
+        setup:
+            System.setProperty('loom.test.lwjgloverride', "true")
+            def gradle = gradleProject(project: "minimalBase", version: version)
+
+            gradle.buildGradle << '''
+                    dependencies {
+                        minecraft "com.mojang:minecraft:1.18"
+                        mappings loom.officialMojangMappings()
+                    }
+                '''
+
+        when:
+            // Run the task twice to ensure its up to date
+            def result = gradle.run(task: "extractNatives")
+
+        then:
+            result.task(":extractNatives").outcome == SUCCESS
+
+        where:
+            version << STANDARD_TEST_VERSIONS
+    }
+}

src/test/groovy/net/fabricmc/loom/test/integration/SignatureFixesTest.groovy

@@ -0,0 +1,57 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.test.integration
+
+import net.fabricmc.loom.test.util.GradleProjectTestTrait
+import spock.lang.Specification
+import spock.lang.Unroll
+
+import static net.fabricmc.loom.test.LoomTestConstants.STANDARD_TEST_VERSIONS
+import static org.gradle.testkit.runner.TaskOutcome.SUCCESS
+
+// Basic test to just ensure it builds.
+class SignatureFixesTest extends Specification implements GradleProjectTestTrait {
+	@Unroll
+	def "build (gradle #version)"() {
+		setup:
+			def gradle = gradleProject(project: "minimalBase", version: version)
+
+			gradle.buildGradle << '''
+                dependencies {
+                    minecraft "com.mojang:minecraft:1.18-pre1"
+                    mappings "net.fabricmc:yarn:1.18-pre1+build.14:v2"
+                }
+            '''
+
+		when:
+			def result = gradle.run(task: "build")
+
+		then:
+			result.task(":build").outcome == SUCCESS
+
+		where:
+			version << STANDARD_TEST_VERSIONS
+	}
+}

src/test/groovy/net/fabricmc/loom/test/integration/SimpleProjectTest.groovy

@@ -51,6 +51,7 @@ class SimpleProjectTest extends Specification implements GradleProjectTestTrait
 		then:
 			result.task(":build").outcome == SUCCESS
 			gradle.getOutputZipEntry("fabric-example-mod-1.0.0.jar", "META-INF/MANIFEST.MF").contains("Fabric-Loom-Version: 0.0.0+unknown")
+			gradle.getOutputZipEntry("fabric-example-mod-1.0.0-sources.jar", "net/fabricmc/example/mixin/ExampleMixin.java").contains("class_442") // Very basic test to ensure sources got remapped
 
 			serverResult.successful()
 			serverResult.output.contains("Hello simple Fabric mod") // A check to ensure our mod init was actually called

src/test/groovy/net/fabricmc/loom/test/unit/IdeaClasspathModificationsTest.groovy

@@ -0,0 +1,104 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2021 FabricMC
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package net.fabricmc.loom.test.unit
+
+import net.fabricmc.loom.configuration.ide.RunConfig
+import net.fabricmc.loom.configuration.ide.idea.IdeaSyncTask
+import org.intellij.lang.annotations.Language
+import spock.lang.Specification
+
+import java.nio.charset.StandardCharsets
+
+class IdeaClasspathModificationsTest extends Specification {
+
+    def "configure exclusions"() {
+        when:
+            def input = fromDummy()
+            def output = IdeaSyncTask.setClasspathModificationsInXml(input, ["/path/to/file.jar"])
+
+        then:
+            output == EXPECTED
+    }
+
+    def "re-configure exclusions"() {
+        when:
+            def input = fromDummy()
+            def output = IdeaSyncTask.setClasspathModificationsInXml(input, ["/path/to/file.jar"])
+            output = IdeaSyncTask.setClasspathModificationsInXml(output, ["/path/to/file.jar", "/path/to/another.jar"])
+
+        then:
+            output == EXPECTED2
+    }
+
+    private String fromDummy() {
+        String dummyConfig
+
+        IdeaSyncTask.class.getClassLoader().getResourceAsStream("idea_run_config_template.xml").withCloseable {
+            dummyConfig = new String(it.readAllBytes(), StandardCharsets.UTF_8)
+        }
+
+        dummyConfig = dummyConfig.replace("%NAME%", "Minecraft Client")
+        dummyConfig = dummyConfig.replace("%MAIN_CLASS%", "net.minecraft.client.Main")
+        dummyConfig = dummyConfig.replace("%IDEA_MODULE%", "main.test")
+        dummyConfig = dummyConfig.replace("%RUN_DIRECTORY%", ".run")
+        dummyConfig = dummyConfig.replace("%PROGRAM_ARGS%", RunConfig.joinArguments([]).replaceAll("\"", """))
+        dummyConfig = dummyConfig.replace("%VM_ARGS%", RunConfig.joinArguments([]).replaceAll("\"", """))
+
+        return dummyConfig
+    }
+
+    @Language("XML")
+    private static final String EXPECTED = '''
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" factoryName="Application" name="Minecraft Client" type="Application">
+    <option name="MAIN_CLASS_NAME" value="net.minecraft.client.Main"/>
+    <module name="main.test"/>
+    <option name="PROGRAM_PARAMETERS" value=""/>
+    <option name="VM_PARAMETERS" value=""/>
+    <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/.run/"/>
+    <method v="2">
+      <option enabled="true" name="Make"/>
+    </method>
+  <classpathModifications><entry exclude="true" path="/path/to/file.jar"/></classpathModifications></configuration>
+</component>
+'''.trim()
+
+    @Language("XML")
+    private static final String EXPECTED2 = '''
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" factoryName="Application" name="Minecraft Client" type="Application">
+    <option name="MAIN_CLASS_NAME" value="net.minecraft.client.Main"/>
+    <module name="main.test"/>
+    <option name="PROGRAM_PARAMETERS" value=""/>
+    <option name="VM_PARAMETERS" value=""/>
+    <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/.run/"/>
+    <method v="2">
+      <option enabled="true" name="Make"/>
+    </method>
+  <classpathModifications><entry exclude="true" path="/path/to/file.jar"/><entry exclude="true" path="/path/to/another.jar"/></classpathModifications></configuration>
+</component>
+'''.trim()
+
+}

src/test/groovy/net/fabricmc/loom/test/unit/RunConfigUnitTest.groovy

@@ -33,6 +33,6 @@ class RunConfigUnitTest extends Specification {
             def args = RunConfig.joinArguments(["-Dfabric.test=123", "-Dfabric.test=abc 123"])
 
         then:
-            args == '"-Dfabric.test=123" "-Dfabric.test=abc 123"'
+            args == '-Dfabric.test=123 "-Dfabric.test=abc 123"'
     }
 }

src/test/groovy/net/fabricmc/loom/test/unit/layeredmappings/LayeredMappingSpecBuilderTest.groovy

@@ -30,28 +30,29 @@ import net.fabricmc.loom.configuration.providers.mappings.LayeredMappingSpecBuil
 import net.fabricmc.loom.configuration.providers.mappings.intermediary.IntermediaryMappingsSpec
 import net.fabricmc.loom.configuration.providers.mappings.mojmap.MojangMappingsSpec
 import net.fabricmc.loom.configuration.providers.mappings.parchment.ParchmentMappingsSpec
-import org.gradle.api.Action
-import org.gradle.util.ConfigureUtil
+import net.fabricmc.loom.util.ClosureAction
+import spock.lang.Specification
 
 class LayeredMappingSpecBuilderTest extends LayeredMappingsSpecification {
     def "simple mojmap" () {
         when:
-            def spec = layered() {
+            def spec = layered {
                 officialMojangMappings()
             }
             def layers = spec.layers()
         then:
-            spec.version == "layered+hash.2198"
             layers.size() == 2
+            spec.version == "layered+hash.2198"
             layers[0].class == IntermediaryMappingsSpec
             layers[1].class == MojangMappingsSpec
     }
 
     def "simple mojmap with parchment" () {
         when:
+            def dep = "I like cake"
             def spec = layered() {
                 officialMojangMappings()
-                parchment("I like cake")
+                parchment(dep)
             }
             def layers = spec.layers()
             def parchment = layers[2] as ParchmentMappingsSpec
@@ -87,7 +88,7 @@ class LayeredMappingSpecBuilderTest extends LayeredMappingsSpecification {
 
     def "simple mojmap with parchment keep prefix alternate hash" () {
         when:
-            def spec = layered() {
+            def spec = layered {
                 officialMojangMappings()
                 parchment("I really like cake") {
                     it.removePrefix = false
@@ -105,14 +106,9 @@ class LayeredMappingSpecBuilderTest extends LayeredMappingsSpecification {
             parchment.removePrefix() == false
     }
 
-    // Gradle does this big of magic behind the scenes
     LayeredMappingSpec layered(@DelegatesTo(LayeredMappingSpecBuilderImpl) Closure cl) {
-        return layeredAction(ConfigureUtil.configureUsing(cl))
-    }
-
-    LayeredMappingSpec layeredAction(Action<LayeredMappingSpecBuilderImpl> action) {
         LayeredMappingSpecBuilderImpl builder = new LayeredMappingSpecBuilderImpl(null)
-        action.execute(builder)
+        new ClosureAction(cl).execute(builder)
         return builder.build()
     }
 }

src/test/resources/patches/fabric_api.patch

@@ -1,6 +1,6 @@
 diff --git a/build.gradle b/build.gradle
---- a/build.gradle	(revision ce6198f63bbe0e17ba631420e9186fb72cc8b2af)
-+++ b/build.gradle	(date 1637848132986)
+--- a/build.gradle	(revision 71b634e5b7845296b11be3fa6545f4fbfacc017f)
++++ b/build.gradle	(date 1638654919842)
 @@ -31,17 +31,7 @@
  		throw new NullPointerException("Could not find version for " + project.name)
  	}
@@ -20,43 +20,3 @@ diff --git a/build.gradle b/build.gradle
  }
 
  def getBranch() {
-@@ -132,9 +122,8 @@
- 		include "**/*.java"
- 	}
-
--	task sourcesJar(type: Jar, dependsOn: classes) {
--		archiveClassifier = "sources"
--		from sourceSets.main.allSource
-+	java {
-+		withSourcesJar()
- 	}
-
- 	checkstyle {
-@@ -229,12 +218,16 @@
- 		publications {
- 			mavenJava(MavenPublication) {
- 				from components.java
-+
-+				artifact javadocJar
- 			}
- 		}
-
- 		setupRepositories(repositories)
- 	}
-
-+	loom.disableDeprecatedPomGeneration(publishing.publications.mavenJava)
-+
- 	javadoc.enabled = false
-
- 	afterEvaluate {
-@@ -242,10 +235,6 @@
- 		genSourcesWithFernFlower.enabled = false
- 		genSourcesWithCfr.enabled = false
- 		unpickJar.enabled = false
--
--		// Work around a loom bug causing empty jars to be pushed to maven local.
--		publishMavenJavaPublicationToMavenLocal.dependsOn rootProject.tasks.getByName("remapAllJars")
--		publishMavenJavaPublicationToMavenLocal.dependsOn rootProject.tasks.getByName("remapAllSources")
- 	}
- }
-

src/test/resources/projects/decompile/build.gradle

@@ -7,3 +7,7 @@ dependencies {
 	mappings "net.fabricmc:yarn:21w38a+build.11:v2"
 	modImplementation "net.fabricmc:fabric-loader:0.11.7"
 }
+
+tasks.named("genSourcesWithCfr") {
+	options.put("test", "value")
+}

src/test/resources/projects/interfaceInjection/build.gradle

@@ -0,0 +1,18 @@
+// This is used by a range of tests that append to this file before running the gradle tasks.
+// Can be used for tests that require minimal custom setup
+plugins {
+	id 'fabric-loom'
+	id 'maven-publish'
+}
+
+archivesBaseName = "fabric-example-mod"
+version = "1.0.0"
+group = "com.example"
+
+dependencies {
+	minecraft "com.mojang:minecraft:1.17.1"
+	mappings "net.fabricmc:yarn:1.17.1+build.59:v2"
+	modImplementation "net.fabricmc:fabric-loader:0.11.6"
+
+	modImplementation files("dummy.jar")
+}

src/test/resources/projects/interfaceInjection/dummyDependency/fabric.mod.json

@@ -0,0 +1,12 @@
+{
+  "schemaVersion": 1,
+  "id": "dummy",
+  "version": "1",
+  "name": "Dummy Mod",
+  "custom": {
+    "fabric-api:module-lifecycle": "stable",
+    "loom:injected_interfaces": {
+      "net/minecraft/class_2248": ["InjectedInterface"]
+    }
+  }
+}

src/test/resources/projects/interfaceInjection/src/main/java/ExampleMod.java

@@ -0,0 +1,10 @@
+import net.minecraft.block.Blocks;
+
+import net.fabricmc.api.ModInitializer;
+
+public class ExampleMod implements ModInitializer {
+	@Override
+	public void onInitialize() {
+		Blocks.AIR.newMethodThatDidNotExist();
+	}
+}

src/test/resources/projects/interfaceInjection/src/main/java/InjectedInterface.java

@@ -0,0 +1,5 @@
+
+public interface InjectedInterface {
+	default void newMethodThatDidNotExist() {
+	}
+}

src/test/resources/projects/mixinApAutoRefmap/src/main/java/net/fabricmc/example/mixin/ExampleMixinSubfolder.java

@@ -0,0 +1,15 @@
+package net.fabricmc.example.mixin;
+
+import net.minecraft.client.gui.screen.ChatScreen;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(ChatScreen.class)
+public class ExampleMixinSubfolder {
+	@Inject(at = @At("HEAD"), method = "init()V")
+	private void init(CallbackInfo info) {
+		System.out.println("This line is printed by an example mod mixin!");
+	}
+}

src/test/resources/projects/mixinApAutoRefmap/src/main/resources/fabric.mod.json

@@ -24,6 +24,7 @@
   },
   "mixins": [
     "main.mixins.json",
+    "subfolder/subfolder.mixins.json",
     {
       "config": "blabla.json",
       "environment": "client"

src/test/resources/projects/mixinApAutoRefmap/src/main/resources/subfolder/subfolder.mixins.json

@@ -0,0 +1,14 @@
+{
+  "required": true,
+  "minVersion": "0.8",
+  "package": "net.fabricmc.example.mixin",
+  "compatibilityLevel": "JAVA_16",
+  "mixins": [
+  ],
+  "client": [
+      "ExampleMixinSubfolder"
+  ],
+  "injectors": {
+    "defaultRequire": 1
+  }
+}

src/test/resources/projects/runconfigs/build.gradle

@@ -31,7 +31,7 @@ archivesBaseName = "fabric-example-mod"
 version = "1.0.0"
 
 dependencies {
-	minecraft "com.mojang:minecraft:1.16.5"
-	mappings "net.fabricmc:yarn:1.16.5+build.5:v2"
-	modImplementation "net.fabricmc:fabric-loader:0.11.2"
+	minecraft "com.mojang:minecraft:1.18.1"
+	mappings "net.fabricmc:yarn:1.18.1+build.12:v2"
+	modImplementation "net.fabricmc:fabric-loader:0.12.12"
 }

src/test/resources/projects/simple/build.gradle

@@ -29,6 +29,9 @@ dependencies {
 
 	// PSA: Some older mods, compiled on Loom 0.2.1, might have outdated Maven POMs.
 	// You may need to force-disable transitiveness on them.
+
+	// Example include
+	include "org.xerial:sqlite-jdbc:3.36.0.3"
 }
 
 tasks.withType(JavaCompile).configureEach {