Support the Vineflower decompiler (#951)

build.gradle

@@ -8,11 +8,37 @@ plugins {
 	id 'checkstyle'
 	id 'jacoco'
 	id 'codenarc'
-	alias(libs.plugins.kotlin)
+	alias(libs.plugins.kotlin) apply false // Delay this so we can perform magic 🪄 first.
 	alias(libs.plugins.spotless)
 	alias(libs.plugins.retry)
 }
 
+/**
+ * Haha this is fun :) The Kotlin gradle plugin triggers deprecation warnings for custom configurations (https://youtrack.jetbrains.com/issue/KT-60879)
+ * We need to make DefaultConfiguration.isSpecialCaseOfChangingUsage think that our configurstion is a special case and not deprecated.
+ * We do this by setting DefaultConfiguration.roleAtCreation to LEGACY, thus isInLegacyRole will now return true.
+ *
+ * Yeah I know we can just ignore the deprecation warning, but doing so wouldn't alert us to issues when testing against pre-release Gradle versions. Also this is more fun :)
+ */
+def brokenConfigurations = [
+	"commonDecompilerRuntimeClasspath",
+	"fernflowerRuntimeClasspath",
+	"cfrRuntimeClasspath",
+	"vineflowerRuntimeClasspath"
+]
+
+configurations.configureEach {
+	if (brokenConfigurations.contains(it.name)) {
+		// For some reason Gradle stops us from using Groovy magic to do this, so lets do it the boring way.
+		def field = org.gradle.api.internal.artifacts.configurations.DefaultConfiguration.class.getDeclaredField("roleAtCreation")
+		field.setAccessible(true)
+		field.set(it, ConfigurationRoles.LEGACY)
+	}
+}
+
+// Ensure we apply the Kotlin plugin after, to allow for the above configuration to take place first
+apply plugin: libs.plugins.kotlin.get().pluginId
+
 tasks.withType(JavaCompile).configureEach {
 	it.options.encoding = "UTF-8"
 }
@@ -62,6 +88,29 @@ configurations.all {
 	}
 }
 
+sourceSets {
+	commonDecompiler {
+		java {
+			srcDir("src/decompilers/common")
+		}
+	}
+	fernflower {
+		java {
+			srcDir("src/decompilers/fernflower")
+		}
+	}
+	cfr {
+		java {
+			srcDir("src/decompilers/cfr")
+		}
+	}
+	vineflower {
+		java {
+			srcDir("src/decompilers/vineflower")
+		}
+	}
+}
+
 dependencies {
 	implementation gradleApi()
 
@@ -89,8 +138,23 @@ dependencies {
 	}
 
 	// decompilers
-	compileOnly runtimeLibs.fernflower
-	compileOnly runtimeLibs.cfr
+	fernflowerCompileOnly runtimeLibs.fernflower
+	fernflowerCompileOnly libs.fabric.mapping.io
+
+	cfrCompileOnly runtimeLibs.cfr
+	cfrCompileOnly libs.fabric.mapping.io
+
+	vineflowerCompileOnly runtimeLibs.vineflower
+	vineflowerCompileOnly libs.fabric.mapping.io
+
+	fernflowerApi sourceSets.commonDecompiler.output
+	cfrApi sourceSets.commonDecompiler.output
+	vineflowerApi sourceSets.commonDecompiler.output
+
+	implementation sourceSets.commonDecompiler.output
+	implementation sourceSets.fernflower.output
+	implementation sourceSets.cfr.output
+	implementation sourceSets.vineflower.output
 
 	// source code remapping
 	implementation libs.fabric.mercury
@@ -130,6 +194,10 @@ jar {
 	}
 
 	from configurations.bootstrap.collect { it.isDirectory() ? it : zipTree(it) }
+	from sourceSets.commonDecompiler.output.classesDirs
+	from sourceSets.cfr.output.classesDirs
+	from sourceSets.fernflower.output.classesDirs
+	from sourceSets.vineflower.output.classesDirs
 }
 
 base {
@@ -222,6 +290,8 @@ test {
 	}
 }
 
+
+import org.gradle.api.internal.artifacts.configurations.ConfigurationRoles
 import org.gradle.launcher.cli.KotlinDslVersion
 import org.gradle.util.GradleVersion
 import org.w3c.dom.Document

gradle/runtime.libs.versions.toml

@@ -2,6 +2,7 @@
 # Decompilers
 fernflower = "2.0.0"
 cfr = "0.2.1"
+vineflower = "1.9.3"
 
 # Runtime depedencies
 mixin-compile-extensions = "0.6.0"
@@ -14,6 +15,7 @@ native-support = "1.0.1"
 # Decompilers
 fernflower = { module = "net.fabricmc:fabric-fernflower", version.ref = "fernflower" }
 cfr = { module = "net.fabricmc:cfr", version.ref = "cfr" }
+vineflower = { module = "org.vineflower:vineflower", version.ref = "vineflower" }
 
 # Runtime depedencies
 mixin-compile-extensions = { module = "net.fabricmc:fabric-mixin-compile-extensions", version.ref = "mixin-compile-extensions" }

gradle/test.libs.versions.toml

@@ -6,7 +6,7 @@ mockito = "5.4.0"
 java-debug = "0.48.0"
 mixin = "0.11.4+mixin.0.8.5"
 
-gradle-nightly = "8.4-20230821223421+0000"
+gradle-nightly = "8.5-20230908221250+0000"
 fabric-loader = "0.14.22"
 fabric-installer = "0.11.1"
 

src/main/java/net/fabricmc/loom/decompilers/cfr/CFRObfuscationMapping.java → src/decompilers/cfr/net/fabricmc/loom/decompilers/cfr/CFRObfuscationMapping.java

@@ -45,7 +45,6 @@
 import org.benf.cfr.reader.util.output.DelegatingDumper;
 import org.benf.cfr.reader.util.output.Dumper;
 
-import net.fabricmc.loom.api.mappings.layered.MappingsNamespace;
 import net.fabricmc.mappingio.MappingReader;
 import net.fabricmc.mappingio.adapter.MappingSourceNsSwitch;
 import net.fabricmc.mappingio.tree.MappingTree;
@@ -66,7 +65,7 @@ public Dumper wrap(Dumper d) {
 	private static MappingTree readMappings(Path input) {
 		try (BufferedReader reader = Files.newBufferedReader(input)) {
 			MemoryMappingTree mappingTree = new MemoryMappingTree();
-			MappingSourceNsSwitch nsSwitch = new MappingSourceNsSwitch(mappingTree, MappingsNamespace.NAMED.toString());
+			MappingSourceNsSwitch nsSwitch = new MappingSourceNsSwitch(mappingTree, "named");
 			MappingReader.read(reader, nsSwitch);
 
 			return mappingTree;

src/main/java/net/fabricmc/loom/decompilers/cfr/CFRSinkFactory.java → src/decompilers/cfr/net/fabricmc/loom/decompilers/cfr/CFRSinkFactory.java

@@ -25,6 +25,7 @@
 package net.fabricmc.loom.decompilers.cfr;
 
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Date;
@@ -37,23 +38,18 @@
 import java.util.jar.JarEntry;
 import java.util.jar.JarOutputStream;
 
-import com.google.common.base.Charsets;
 import org.benf.cfr.reader.api.OutputSinkFactory;
 import org.benf.cfr.reader.api.SinkReturns;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
-import net.fabricmc.loom.util.IOStringConsumer;
+import net.fabricmc.loom.decompilers.LoomInternalDecompiler;
 
 public class CFRSinkFactory implements OutputSinkFactory {
-	private static final Logger ERROR_LOGGER = LoggerFactory.getLogger(CFRSinkFactory.class);
-
 	private final JarOutputStream outputStream;
-	private final IOStringConsumer logger;
+	private final LoomInternalDecompiler.Logger logger;
 	private final Set<String> addedDirectories = new HashSet<>();
 	private final Map<String, Map<Integer, Integer>> lineMap = new TreeMap<>();
 
-	public CFRSinkFactory(JarOutputStream outputStream, IOStringConsumer logger) {
+	public CFRSinkFactory(JarOutputStream outputStream, LoomInternalDecompiler.Logger logger) {
 		this.outputStream = outputStream;
 		this.logger = logger;
 	}
@@ -72,7 +68,7 @@ public <T> Sink<T> getSink(SinkType sinkType, SinkClass sinkClass) {
 		return switch (sinkType) {
 		case JAVA -> (Sink<T>) decompiledSink();
 		case LINENUMBER -> (Sink<T>) lineNumberMappingSink();
-		case EXCEPTION -> (e) -> ERROR_LOGGER.error((String) e);
+		case EXCEPTION -> (e) -> logger.error((String) e);
 		default -> null;
 		};
 	}
@@ -83,7 +79,7 @@ private Sink<SinkReturns.Decompiled> decompiledSink() {
 			if (!filename.isEmpty()) filename += "/";
 			filename += sinkable.getClassName() + ".java";
 
-			byte[] data = sinkable.getJava().getBytes(Charsets.UTF_8);
+			byte[] data = sinkable.getJava().getBytes(StandardCharsets.UTF_8);
 
 			writeToJar(filename, data);
 		};

src/main/java/net/fabricmc/loom/decompilers/cfr/LoomCFRDecompiler.java → src/decompilers/cfr/net/fabricmc/loom/decompilers/cfr/LoomCFRDecompiler.java

@@ -45,45 +45,46 @@
 import org.benf.cfr.reader.util.getopt.OptionsImpl;
 import org.benf.cfr.reader.util.output.SinkDumperFactory;
 
-import net.fabricmc.loom.api.decompilers.DecompilationMetadata;
-import net.fabricmc.loom.api.decompilers.LoomDecompiler;
+import net.fabricmc.loom.decompilers.LoomInternalDecompiler;
 
-public final class LoomCFRDecompiler implements LoomDecompiler {
+public final class LoomCFRDecompiler implements LoomInternalDecompiler {
 	private static final Map<String, String> DECOMPILE_OPTIONS = Map.of(
 			"renameillegalidents", "true",
 			"trackbytecodeloc", "true",
 			"comments", "false"
 	);
 
 	@Override
-	public void decompile(Path compiledJar, Path sourcesDestination, Path linemapDestination, DecompilationMetadata metaData) {
+	public void decompile(LoomInternalDecompiler.Context context) {
+		Path compiledJar = context.compiledJar();
+
 		final String path = compiledJar.toAbsolutePath().toString();
 		final Map<String, String> allOptions = new HashMap<>(DECOMPILE_OPTIONS);
-		allOptions.putAll(metaData.options());
+		allOptions.putAll(context.options());
 
 		final Options options = OptionsImpl.getFactory().create(allOptions);
 
 		ClassFileSourceImpl classFileSource = new ClassFileSourceImpl(options);
 
-		for (Path library : metaData.libraries()) {
+		for (Path library : context.libraries()) {
 			classFileSource.addJarContent(library.toAbsolutePath().toString(), AnalysisType.JAR);
 		}
 
 		classFileSource.informAnalysisRelativePathDetail(null, null);
 
 		DCCommonState state = new DCCommonState(options, classFileSource);
 
-		if (metaData.javaDocs() != null) {
-			state = new DCCommonState(state, new CFRObfuscationMapping(metaData.javaDocs()));
+		if (context.javaDocs() != null) {
+			state = new DCCommonState(state, new CFRObfuscationMapping(context.javaDocs()));
 		}
 
 		final Manifest manifest = new Manifest();
 		manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
 
 		Map<String, Map<Integer, Integer>> lineMap;
 
-		try (JarOutputStream outputStream = new JarOutputStream(Files.newOutputStream(sourcesDestination), manifest)) {
-			CFRSinkFactory cfrSinkFactory = new CFRSinkFactory(outputStream, metaData.logger());
+		try (JarOutputStream outputStream = new JarOutputStream(Files.newOutputStream(context.sourcesDestination()), manifest)) {
+			CFRSinkFactory cfrSinkFactory = new CFRSinkFactory(outputStream, context.logger());
 			SinkDumperFactory dumperFactory = new SinkDumperFactory(cfrSinkFactory, options);
 
 			Driver.doJar(state, path, AnalysisType.JAR, dumperFactory);
@@ -93,7 +94,7 @@ public void decompile(Path compiledJar, Path sourcesDestination, Path linemapDes
 			throw new UncheckedIOException("Failed to decompile", e);
 		}
 
-		writeLineMap(linemapDestination, lineMap);
+		writeLineMap(context.linemapDestination(), lineMap);
 	}
 
 	private void writeLineMap(Path output, Map<String, Map<Integer, Integer>> lineMap) {

src/main/java/net/fabricmc/loom/decompilers/fernflower/FernFlowerUtils.java → src/decompilers/common/net/fabricmc/loom/decompilers/LoomInternalDecompiler.java

@@ -1,7 +1,7 @@
 /*
  * This file is part of fabric-loom, licensed under the MIT License (MIT).
  *
- * Copyright (c) 2016-2022 FabricMC
+ * Copyright (c) 2023 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
@@ -22,23 +22,40 @@
  * SOFTWARE.
  */
 
-package net.fabricmc.loom.decompilers.fernflower;
+package net.fabricmc.loom.decompilers;
 
-import java.io.File;
 import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Collection;
+import java.util.Map;
 
-import org.jetbrains.java.decompiler.util.InterpreterUtil;
+// This is an internal interface to loom, DO NOT USE this in your own plugins.
+public interface LoomInternalDecompiler {
+	void decompile(Context context);
 
-import net.fabricmc.loom.util.ZipUtils;
+	interface Context {
+		Path compiledJar();
 
-public class FernFlowerUtils {
-	public static byte[] getBytecode(String externalPath, String internalPath) throws IOException {
-		File file = new File(externalPath);
+		Path sourcesDestination();
 
-		if (internalPath == null) {
-			return InterpreterUtil.getBytes(file);
-		} else {
-			return ZipUtils.unpack(file.toPath(), internalPath);
-		}
+		Path linemapDestination();
+
+		int numberOfThreads();
+
+		Path javaDocs();
+
+		Collection<Path> libraries();
+
+		Logger logger();
+
+		Map<String, String> options();
+
+		byte[] unpackZip(Path zip, String path) throws IOException;
+	}
+
+	interface Logger {
+		void accept(String data) throws IOException;
+
+		void error(String msg);
 	}
 }