Use tiny-remapper to remap mixin annotation. (#441)

* use tiny-remapper 0.5.0

* add property of useLegacyMixinAp and rename mixin to mixinAp

* disable mixin ap if useLegacyMixinAp is false

* fix tests

* remove experimental for mixinAp

* enable mixin remapper

* revert changes on API

* rename MixinAp*** to Mixin***

* move useLegacyMixinAp inside MixinExtension

* cleaner code

* update test

Co-authored-by: modmuss50 <modmuss50@gmail.com>

17 files changed, 93 insertions, 70 deletions

diff --git a/src/main/java/net/fabricmc/loom/LoomGradleExtension.java b/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
index d3a3a7e8..5c7e2c05 100644
--- a/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
+++ b/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
@@ -43,7 +43,7 @@ import net.fabricmc.loom.configuration.providers.MinecraftProviderImpl;
 import net.fabricmc.loom.configuration.providers.mappings.MappingsProviderImpl;
 import net.fabricmc.loom.configuration.providers.minecraft.MinecraftMappedProvider;
 import net.fabricmc.loom.extension.LoomFiles;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 
 public interface LoomGradleExtension extends LoomGradleExtensionAPI {
 	static LoomGradleExtension get(Project project) {
@@ -102,5 +102,5 @@ public interface LoomGradleExtension extends LoomGradleExtensionAPI {
 	}
 
 	@Override
-	MixinApExtension getMixin();
+	MixinExtension getMixin();
 }
diff --git a/src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java b/src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java
index 26ecb3bd..36809280 100644
--- a/src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java
+++ b/src/main/java/net/fabricmc/loom/api/LoomGradleExtensionAPI.java
@@ -154,11 +154,11 @@ public interface LoomGradleExtensionAPI {
 
 	NamedDomainObjectContainer<RunConfigSettings> getRunConfigs();
 
-	@ApiStatus.Experimental
-	void mixin(Action<MixinApExtensionAPI> action);
+	void mixin(Action<MixinExtensionAPI> action);
 
 	@ApiStatus.Experimental
-	MixinApExtensionAPI getMixin();
+	// TODO: move this from LoomGradleExtensionAPI to LoomGradleExtension once getRefmapName & setRefmapName is removed.
+	MixinExtensionAPI getMixin();
 
 	Property<String> getCustomMinecraftManifest();
 
diff --git a/src/main/java/net/fabricmc/loom/api/MixinApExtensionAPI.java b/src/main/java/net/fabricmc/loom/api/MixinExtensionAPI.java
index e74eecbf..78440ec2 100644
--- a/src/main/java/net/fabricmc/loom/api/MixinApExtensionAPI.java
+++ b/src/main/java/net/fabricmc/loom/api/MixinExtensionAPI.java
@@ -31,7 +31,9 @@ import org.gradle.api.tasks.util.PatternSet;
 import org.jetbrains.annotations.ApiStatus;
 
 @ApiStatus.Experimental
-public interface MixinApExtensionAPI {
+public interface MixinExtensionAPI {
+	Property<Boolean> getUseLegacyMixinAp();
+
 	Property<String> getDefaultRefmapName();
 
 	/**
@@ -45,27 +47,27 @@ public interface MixinApExtensionAPI {
 	void add(SourceSet sourceSet, String refmapName, Action<PatternSet> action);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSet the sourceSet that applies Mixin AP.
 	 * @param refmapName the output ref-map name.
 	 */
 	void add(SourceSet sourceSet, String refmapName);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSet the sourceSet that applies Mixin AP.
 	 * @param action used for filter the mixin json files.
 	 */
 	void add(SourceSet sourceSet, Action<PatternSet> action);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSet the sourceSet that applies Mixin AP.
 	 */
 	void add(SourceSet sourceSet);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSetName the name of sourceSet that applies Mixin AP.
 	 * @param refmapName the output ref-map name.
 	 * @param action used for filter the mixin json files.
@@ -73,21 +75,21 @@ public interface MixinApExtensionAPI {
 	void add(String sourceSetName, String refmapName, Action<PatternSet> action);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSetName the name of sourceSet that applies Mixin AP.
 	 * @param refmapName the output ref-map name.
 	 */
 	void add(String sourceSetName, String refmapName);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSetName the name of sourceSet that applies Mixin AP.
 	 * @param action used for filter the mixin json files.
 	 */
 	void add(String sourceSetName, Action<PatternSet> action);
 
 	/**
-	 * Apply Mixin AP to sourceSet. See {@link MixinApExtensionAPI#add(SourceSet, String, Action)} for more detail.
+	 * Apply Mixin AP to sourceSet. See {@link MixinExtensionAPI#add(SourceSet, String, Action)} for more detail.
 	 * @param sourceSetName the name of sourceSet that applies Mixin AP.
 	 */
 	void add(String sourceSetName);
diff --git a/src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java b/src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java
index 77053213..cbacf26e 100644
--- a/src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java
+++ b/src/main/java/net/fabricmc/loom/build/MixinRefmapHelper.java
@@ -48,7 +48,7 @@ import org.zeroturnaround.zip.transform.ZipEntryTransformerEntry;
 
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.LoomGradlePlugin;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 
 public final class MixinRefmapHelper {
 	private MixinRefmapHelper() { }
@@ -57,14 +57,14 @@ public final class MixinRefmapHelper {
 
 	public static boolean addRefmapName(Project project, Path outputPath) {
 		try {
-			MixinApExtension mixin = LoomGradleExtension.get(project).getMixin();
+			MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 			File output = outputPath.toFile();
 
 			Collection<String> allMixinConfigs = getMixinConfigurationFiles(readFabricModJson(output));
 
 			return mixin.getMixinSourceSetsStream().map(sourceSet -> {
-				MixinApExtension.MixinInformationContainer container = Objects.requireNonNull(
-						MixinApExtension.getMixinInformationContainer(sourceSet)
+				MixinExtension.MixinInformationContainer container = Objects.requireNonNull(
+						MixinExtension.getMixinInformationContainer(sourceSet)
 				);
 
 				Stream<String> mixinConfigs = sourceSet.getResources()
diff --git a/src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java b/src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java
index c4f89d99..f87ccc21 100644
--- a/src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java
+++ b/src/main/java/net/fabricmc/loom/build/mixin/AnnotationProcessorInvoker.java
@@ -39,7 +39,7 @@ import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.artifacts.ConfigurationContainer;
 import org.gradle.api.tasks.SourceSet;
 
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.util.Constants;
 
@@ -65,7 +65,7 @@ public abstract class AnnotationProcessorInvoker<T extends Task> {
 	}
 
 	protected static Collection<Configuration> getApConfigurations(Project project, Function<String, String> getApConfigNameFunc) {
-		MixinApExtension mixin = LoomGradleExtension.get(project).getMixin();
+		MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 		return mixin.getApConfigurationsStream(getApConfigNameFunc).collect(Collectors.toList());
 	}
 
@@ -80,7 +80,7 @@ public abstract class AnnotationProcessorInvoker<T extends Task> {
 	private void passMixinArguments(T task, SourceSet sourceSet) {
 		try {
 			LoomGradleExtension loom = LoomGradleExtension.get(project);
-			String refmapName = Objects.requireNonNull(MixinApExtension.getMixinInformationContainer(sourceSet)).refmapNameProvider().get();
+			String refmapName = Objects.requireNonNull(MixinExtension.getMixinInformationContainer(sourceSet)).refmapNameProvider().get();
 			Map<String, String> args = new HashMap<>() {{
 					put(Constants.MixinArguments.IN_MAP_FILE_NAMED_INTERMEDIARY, loom.getMappingsProvider().tinyMappings.toFile().getCanonicalPath());
 					put(Constants.MixinArguments.OUT_MAP_FILE_NAMED_INTERMEDIARY, loom.getNextMixinMappings().getCanonicalPath());
diff --git a/src/main/java/net/fabricmc/loom/build/mixin/JavaApInvoker.java b/src/main/java/net/fabricmc/loom/build/mixin/JavaApInvoker.java
index b1109f1c..770dbda5 100644
--- a/src/main/java/net/fabricmc/loom/build/mixin/JavaApInvoker.java
+++ b/src/main/java/net/fabricmc/loom/build/mixin/JavaApInvoker.java
@@ -35,7 +35,7 @@ import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.compile.JavaCompile;
 
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 
 public class JavaApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 	public JavaApInvoker(Project project) {
@@ -46,7 +46,7 @@ public class JavaApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 	}
 
 	private static Map<SourceSet, JavaCompile> getInvokerTasks(Project project) {
-		MixinApExtension mixin = LoomGradleExtension.get(project).getMixin();
+		MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 		return mixin.getInvokerTasksStream(AnnotationProcessorInvoker.JAVA)
 				.collect(Collectors.toMap(Map.Entry::getKey, entry -> Objects.requireNonNull((JavaCompile) entry.getValue())));
 	}
diff --git a/src/main/java/net/fabricmc/loom/build/mixin/KaptApInvoker.java b/src/main/java/net/fabricmc/loom/build/mixin/KaptApInvoker.java
index d49a473a..7bf54247 100644
--- a/src/main/java/net/fabricmc/loom/build/mixin/KaptApInvoker.java
+++ b/src/main/java/net/fabricmc/loom/build/mixin/KaptApInvoker.java
@@ -40,7 +40,7 @@ import org.gradle.api.tasks.compile.JavaCompile;
 import org.jetbrains.kotlin.gradle.plugin.KaptExtension;
 
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 
 public class KaptApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 	private final KaptExtension kaptExtension = project.getExtensions().getByType(KaptExtension.class);
@@ -66,7 +66,7 @@ public class KaptApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 	}
 
 	private static Map<SourceSet, JavaCompile> getInvokerTasks(Project project) {
-		MixinApExtension mixin = LoomGradleExtension.get(project).getMixin();
+		MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 		return mixin.getInvokerTasksStream(AnnotationProcessorInvoker.JAVA)
 				.collect(Collectors.toMap(Map.Entry::getKey, entry -> Objects.requireNonNull((JavaCompile) entry.getValue())));
 	}
@@ -82,7 +82,7 @@ public class KaptApInvoker extends AnnotationProcessorInvoker<JavaCompile> {
 			SourceSet sourceSet = entry.getKey();
 			task.doLast(t -> {
 				try {
-					String refmapName = Objects.requireNonNull(MixinApExtension.getMixinInformationContainer(sourceSet)).refmapNameProvider().get();
+					String refmapName = Objects.requireNonNull(MixinExtension.getMixinInformationContainer(sourceSet)).refmapNameProvider().get();
 					Path src = Paths.get(getRefmapDestination(task, refmapName));
 					Path dest = Paths.get(task.getDestinationDir().toString(), refmapName);
 
diff --git a/src/main/java/net/fabricmc/loom/build/mixin/ScalaApInvoker.java b/src/main/java/net/fabricmc/loom/build/mixin/ScalaApInvoker.java
index 8597cdd9..e24442eb 100644
--- a/src/main/java/net/fabricmc/loom/build/mixin/ScalaApInvoker.java
+++ b/src/main/java/net/fabricmc/loom/build/mixin/ScalaApInvoker.java
@@ -35,7 +35,7 @@ import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.scala.ScalaCompile;
 
 import net.fabricmc.loom.LoomGradleExtension;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 
 public class ScalaApInvoker extends AnnotationProcessorInvoker<ScalaCompile> {
 	public ScalaApInvoker(Project project) {
@@ -47,7 +47,7 @@ public class ScalaApInvoker extends AnnotationProcessorInvoker<ScalaCompile> {
 	}
 
 	private static Map<SourceSet, ScalaCompile> getInvokerTasks(Project project) {
-		MixinApExtension mixin = LoomGradleExtension.get(project).getMixin();
+		MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
 		return mixin.getInvokerTasksStream(AnnotationProcessorInvoker.SCALA)
 				.collect(Collectors.toMap(Map.Entry::getKey, entry -> Objects.requireNonNull((ScalaCompile) entry.getValue())));
 	}
diff --git a/src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java b/src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java
index f572d31a..81f8bf4c 100644
--- a/src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java
+++ b/src/main/java/net/fabricmc/loom/configuration/CompileConfiguration.java
@@ -39,7 +39,7 @@ 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.mappings.MappingsProviderImpl;
-import net.fabricmc.loom.extension.MixinApExtension;
+import net.fabricmc.loom.extension.MixinExtension;
 import net.fabricmc.loom.util.Constants;
 
 public final class CompileConfiguration {
@@ -137,14 +137,20 @@ public final class CompileConfiguration {
 				extension.getUnmappedModCollection().from(jarTask);
 			}
 
+			MixinExtension mixin = LoomGradleExtension.get(project).getMixin();
+
+			if (!mixin.getUseLegacyMixinAp().get()) {
+				return;
+			}
+
+			mixin.init();
+
 			// Disable some things used by log4j via the mixin AP that prevent it from being garbage collected
 			System.setProperty("log4j2.disable.jmx", "true");
 			System.setProperty("log4j.shutdownHookEnabled", "false");
 			System.setProperty("log4j.skipJansi", "true");
 
 			project.getLogger().info("Configuring compiler arguments for Java");
-			MixinApExtension mixinApExtension = LoomGradleExtension.get(project).getMixin();
-			mixinApExtension.init();
 
 			new JavaApInvoker(project).configureMixin();
 
diff --git a/src/main/java/net/fabricmc/loom/configuration/LoomDependencyManager.java b/src/main/java/net/fabricmc/loom/configuration/LoomDependencyManager.java
index 174cb9b8..c3fdafaf 100644
--- a/src/main/java/net/fabricmc/loom/configuration/LoomDependencyManager.java
+++ b/src/main/java/net/fabricmc/loom/configuration/LoomDependencyManager.java
@@ -190,7 +190,8 @@ public class LoomDependencyManager {
 			modDep.setTransitive(false);
 			loaderDepsConfig.getDependencies().add(modDep);
 
-			if (!extension.ideSync()) {
+			// 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()) {
 				apDepsConfig.getDependencies().add(modDep);
 			}
 
diff --git a/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionApiImpl.java b/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionApiImpl.java
index 610808f6..9f0396ad 100644
--- a/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionApiImpl.java
+++ b/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionApiImpl.java
@@ -35,7 +35,7 @@ import org.gradle.api.provider.Property;
 import org.gradle.api.publish.maven.MavenPublication;
 
 import net.fabricmc.loom.api.LoomGradleExtensionAPI;
-import net.fabricmc.loom.api.MixinApExtensionAPI;
+import net.fabricmc.loom.api.MixinExtensionAPI;
 import net.fabricmc.loom.api.decompilers.LoomDecompiler;
 import net.fabricmc.loom.configuration.ide.RunConfigSettings;
 import net.fabricmc.loom.configuration.processors.JarProcessor;
@@ -135,7 +135,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 	}
 
 	@Override
-	public void mixin(Action<MixinApExtensionAPI> action) {
+	public void mixin(Action<MixinExtensionAPI> action) {
 		action.execute(getMixin());
 	}
 
@@ -181,7 +181,7 @@ public abstract class LoomGradleExtensionApiImpl implements LoomGradleExtensionA
 		}
 
 		@Override
-		public MixinApExtension getMixin() {
+		public MixinExtension getMixin() {
 			throw new RuntimeException("Yeah... something is really wrong");
 		}
 	}
diff --git a/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionImpl.java b/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionImpl.java
index 98510b3c..f35e7939 100644
--- a/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionImpl.java
+++ b/src/main/java/net/fabricmc/loom/extension/LoomGradleExtensionImpl.java
@@ -47,7 +47,7 @@ import net.fabricmc.loom.configuration.processors.JarProcessorManager;
 
 public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implements LoomGradleExtension {
 	private final Project project;
-	private final MixinApExtension mixinApExtension;
+	private final MixinExtension mixinApExtension;
 	private final LoomFiles loomFiles;
 	private final ConfigurableFileCollection unmappedMods;
 
@@ -64,7 +64,7 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 		super(project, files);
 		this.project = project;
 		// Initiate with newInstance to allow gradle to decorate our extension
-		this.mixinApExtension = project.getObjects().newInstance(MixinApExtensionImpl.class, project);
+		this.mixinApExtension = project.getObjects().newInstance(MixinExtensionImpl.class, project);
 		this.loomFiles = files;
 		this.unmappedMods = project.files();
 	}
@@ -165,7 +165,7 @@ public class LoomGradleExtensionImpl extends LoomGradleExtensionApiImpl implemen
 	}
 
 	@Override
-	public MixinApExtension getMixin() {
+	public MixinExtension getMixin() {
 		return this.mixinApExtension;
 	}
 }
diff --git a/src/main/java/net/fabricmc/loom/extension/MinecraftGradleExtension.java b/src/main/java/net/fabricmc/loom/extension/MinecraftGradleExtension.java
index 4da6011e..a209a307 100644
--- a/src/main/java/net/fabricmc/loom/extension/MinecraftGradleExtension.java
+++ b/src/main/java/net/fabricmc/loom/extension/MinecraftGradleExtension.java
@@ -34,7 +34,7 @@ import org.gradle.api.provider.Property;
 import org.gradle.api.publish.maven.MavenPublication;
 
 import net.fabricmc.loom.api.LoomGradleExtensionAPI;
-import net.fabricmc.loom.api.MixinApExtensionAPI;
+import net.fabricmc.loom.api.MixinExtensionAPI;
 import net.fabricmc.loom.api.decompilers.LoomDecompiler;
 import net.fabricmc.loom.configuration.ide.RunConfigSettings;
 import net.fabricmc.loom.configuration.processors.JarProcessor;
@@ -116,13 +116,13 @@ public class MinecraftGradleExtension implements LoomGradleExtensionAPI {
 	}
 
 	@Override
-	public void mixin(Action<MixinApExtensionAPI> action) {
+	public void mixin(Action<MixinExtensionAPI> action) {
 		reportDeprecation();
 		parent.mixin(action);
 	}
 
 	@Override
-	public MixinApExtensionAPI getMixin() {
+	public MixinExtensionAPI getMixin() {
 		reportDeprecation();
 		return parent.getMixin();
 	}
diff --git a/src/main/java/net/fabricmc/loom/extension/MixinApExtension.java b/src/main/java/net/fabricmc/loom/extension/MixinExtension.java
index 73e78858..b3e76362 100644
--- a/src/main/java/net/fabricmc/loom/extension/MixinApExtension.java
+++ b/src/main/java/net/fabricmc/loom/extension/MixinExtension.java
@@ -41,13 +41,13 @@ import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
-import net.fabricmc.loom.api.MixinApExtensionAPI;
+import net.fabricmc.loom.api.MixinExtensionAPI;
 
 /**
  * A gradle extension to configure mixin annotation processor.
  */
 @ApiStatus.Experimental
-public interface MixinApExtension extends MixinApExtensionAPI {
+public interface MixinExtension extends MixinExtensionAPI {
 	String MIXIN_INFORMATION_CONTAINER = "mixin";
 
 	/**
diff --git a/src/main/java/net/fabricmc/loom/extension/MixinApExtensionApiImpl.java b/src/main/java/net/fabricmc/loom/extension/MixinExtensionApiImpl.java
index db06c481..e99eef26 100644
--- a/src/main/java/net/fabricmc/loom/extension/MixinApExtensionApiImpl.java
+++ b/src/main/java/net/fabricmc/loom/extension/MixinExtensionApiImpl.java
@@ -24,6 +24,8 @@
 
 package net.fabricmc.loom.extension;
 
+import java.util.Objects;
+
 import org.gradle.api.Action;
 import org.gradle.api.InvalidUserDataException;
 import org.gradle.api.Project;
@@ -33,18 +35,30 @@ import org.gradle.api.provider.Provider;
 import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.util.PatternSet;
 
-import net.fabricmc.loom.api.MixinApExtensionAPI;
+import net.fabricmc.loom.api.MixinExtensionAPI;
+
+public abstract class MixinExtensionApiImpl implements MixinExtensionAPI {
+	protected final Project project;
+	protected final Property<Boolean> useMixinAp;
 
-public abstract class MixinApExtensionApiImpl implements MixinApExtensionAPI {
-	protected abstract Project getProject();
+	public MixinExtensionApiImpl(Project project) {
+		this.project = Objects.requireNonNull(project);
+		this.useMixinAp = project.getObjects().property(Boolean.class)
+				.convention(false);
+	}
 
 	protected final PatternSet add0(SourceSet sourceSet, String refmapName) {
-		return add0(sourceSet, getProject().provider(() -> refmapName));
+		return add0(sourceSet, project.provider(() -> refmapName));
 	}
 
 	protected abstract PatternSet add0(SourceSet sourceSet, Provider<String> refmapName);
 
 	@Override
+	public Property<Boolean> getUseLegacyMixinAp() {
+		return useMixinAp;
+	}
+
+	@Override
 	public void add(SourceSet sourceSet, String refmapName, Action<PatternSet> action) {
 		PatternSet pattern = add0(sourceSet, refmapName);
 		action.execute(pattern);
@@ -57,7 +71,7 @@ public abstract class MixinApExtensionApiImpl implements MixinApExtensionAPI {
 
 	@Override
 	public void add(String sourceSetName, String refmapName, Action<PatternSet> action) {
-		add(sourceSetName, getProject().provider(() -> refmapName), action);
+		add(sourceSetName, project.provider(() -> refmapName), action);
 	}
 
 	public void add(String sourceSetName, Provider<String> refmapName, Action<PatternSet> action) {
@@ -96,7 +110,7 @@ public abstract class MixinApExtensionApiImpl implements MixinApExtensionAPI {
 
 	private SourceSet resolveSourceSet(String sourceSetName) {
 		// try to find sourceSet with name sourceSetName in this project
-		SourceSet sourceSet = getProject().getConvention().getPlugin(JavaPluginConvention.class)
+		SourceSet sourceSet = project.getConvention().getPlugin(JavaPluginConvention.class)
 				.getSourceSets().findByName(sourceSetName);
 
 		if (sourceSet == null) {
@@ -107,18 +121,13 @@ public abstract class MixinApExtensionApiImpl implements MixinApExtensionAPI {
 	}
 
 	// This is here to ensure that LoomGradleExtensionApiImpl compiles without any unimplemented methods
-	private final class EnsureCompile extends MixinApExtensionApiImpl {
+	private final class EnsureCompile extends MixinExtensionApiImpl {
 		private EnsureCompile() {
-			super();
+			super(null);
 			throw new RuntimeException();
 		}
 
 		@Override
-		protected Project getProject() {
-			throw new RuntimeException("Yeah... something is really wrong");
-		}
-
-		@Override
 		public Property<String> getDefaultRefmapName() {
 			throw new RuntimeException("Yeah... something is really wrong");
 		}
diff --git a/src/main/java/net/fabricmc/loom/extension/MixinApExtensionImpl.java b/src/main/java/net/fabricmc/loom/extension/MixinExtensionImpl.java
index 3602e75a..074251e4 100644
--- a/src/main/java/net/fabricmc/loom/extension/MixinApExtensionImpl.java
+++ b/src/main/java/net/fabricmc/loom/extension/MixinExtensionImpl.java
@@ -47,39 +47,37 @@ import org.gradle.api.tasks.SourceSet;
 import org.gradle.api.tasks.util.PatternSet;
 import org.jetbrains.annotations.NotNull;
 
-public class MixinApExtensionImpl extends MixinApExtensionApiImpl implements MixinApExtension {
+public class MixinExtensionImpl extends MixinExtensionApiImpl implements MixinExtension {
 	private boolean isDefault;
-	private final Project project;
 	private final Property<String> defaultRefmapName;
 
 	@Inject
-	public MixinApExtensionImpl(Project project) {
+	public MixinExtensionImpl(Project project) {
+		super(project);
 		this.isDefault = true;
-		this.project = project;
 		this.defaultRefmapName = project.getObjects().property(String.class)
 				.convention(project.provider(this::getDefaultMixinRefmapName));
 	}
 
 	@Override
-	public Project getProject() {
-		return this.project;
-	}
-
-	@Override
 	public Property<String> getDefaultRefmapName() {
+		if (!super.getUseLegacyMixinAp().get()) throw new IllegalStateException("You need to set useLegacyMixinAp = true to configure Mixin annotation processor.");
+
 		return defaultRefmapName;
 	}
 
 	private String getDefaultMixinRefmapName() {
-		String defaultRefmapName = getProject().getConvention().getPlugin(BasePluginConvention.class).getArchivesBaseName() + "-refmap.json";
-		getProject().getLogger().info("Could not find refmap definition, will be using default name: " + defaultRefmapName);
+		String defaultRefmapName = project.getConvention().getPlugin(BasePluginConvention.class).getArchivesBaseName() + "-refmap.json";
+		project.getLogger().info("Could not find refmap definition, will be using default name: " + defaultRefmapName);
 		return defaultRefmapName;
 	}
 
 	@Override
 	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"));
-		MixinApExtension.setMixinInformationContainer(sourceSet, new MixinApExtension.MixinInformationContainer(sourceSet, refmapName, pattern));
+		MixinExtension.setMixinInformationContainer(sourceSet, new MixinExtension.MixinInformationContainer(sourceSet, refmapName, pattern));
 
 		isDefault = false;
 
@@ -90,7 +88,7 @@ public class MixinApExtensionImpl extends MixinApExtensionApiImpl implements Mix
 	@NotNull
 	public Stream<SourceSet> getMixinSourceSetsStream() {
 		return project.getConvention().getPlugin(JavaPluginConvention.class).getSourceSets().stream()
-				.filter(sourceSet -> MixinApExtension.getMixinInformationContainer(sourceSet) != null);
+				.filter(sourceSet -> MixinExtension.getMixinInformationContainer(sourceSet) != null);
 	}
 
 	@Override
diff --git a/src/main/java/net/fabricmc/loom/task/RemapJarTask.java b/src/main/java/net/fabricmc/loom/task/RemapJarTask.java
index 98e6cee1..2bab9f5a 100644
--- a/src/main/java/net/fabricmc/loom/task/RemapJarTask.java
+++ b/src/main/java/net/fabricmc/loom/task/RemapJarTask.java
@@ -73,6 +73,7 @@ import net.fabricmc.loom.util.ZipReprocessorUtil;
 import net.fabricmc.stitch.util.Pair;
 import net.fabricmc.tinyremapper.TinyRemapper;
 import net.fabricmc.tinyremapper.TinyUtils;
+import net.fabricmc.tinyremapper.extension.mixin.MixinExtension;
 
 public class RemapJarTask extends Jar {
 	private static final String MANIFEST_PATH = "META-INF/MANIFEST.MF";
@@ -95,6 +96,10 @@ public class RemapJarTask extends Jar {
 		// false by default, I have no idea why I have to do it for this property and not the other one
 		remapAccessWidener.set(false);
 		addDefaultNestedDependencies.set(true);
+
+		if (!LoomGradleExtension.get(getProject()).getMixin().getUseLegacyMixinAp().get()) {
+			remapOptions.add(b -> b.extension(new MixinExtension()));
+		}
 	}
 
 	@TaskAction
@@ -171,8 +176,10 @@ public class RemapJarTask extends Jar {
 						throw new RuntimeException("Failed to remap " + input + " to " + output + " - file missing!");
 					}
 
-					if (MixinRefmapHelper.addRefmapName(project, output)) {
-						project.getLogger().debug("Transformed mixin reference maps in output JAR!");
+					if (extension.getMixin().getUseLegacyMixinAp().get()) {
+						if (MixinRefmapHelper.addRefmapName(project, output)) {
+							project.getLogger().debug("Transformed mixin reference maps in output JAR!");
+						}
 					}
 
 					if (getAddNestedDependencies().getOrElse(false)) {