Official Mojang Mappings support

# Please read and understand the EULA before using!

Use in your build.gradle with the following:

`mappings minecraft.officialMojangMappings()`

To automatically migrate to Mojang mappings run the following:

`gradlew.bat migrateMappings --mappings "net.mojang.minecraft:mappings:1.16.2"`

Co-authored-by: Ramid Khan <ramidzkh@gmail.com>

.github/workflows/test-push.yml

@@ -4,7 +4,7 @@ jobs:
   gradle:
     strategy:
       matrix:
-        gradle: [4.9, 4.10.2, 6.5.1]
+        gradle: [4.9, 4.10.2, 6.6]
         java: [jdk8, jdk11, jdk14]
         exclude: # Dont run older gradle versions on newer java
           - java: jdk14

build.gradle

@@ -53,6 +53,7 @@ dependencies {
 	implementation ('net.fabricmc:lorenz-tiny:2.0.0+build.2') {
 		transitive = false
 	}
+	implementation ('org.cadixdev:lorenz-io-proguard:0.5.3')
 
 	// decompilers
 	implementation ('net.fabricmc:procyon-fabric-compilertools:0.5.35.13')

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

@@ -53,6 +53,7 @@ import net.fabricmc.loom.providers.MappingsProvider;
 import net.fabricmc.loom.providers.MinecraftMappedProvider;
 import net.fabricmc.loom.providers.MinecraftProvider;
 import net.fabricmc.loom.util.LoomDependencyManager;
+import net.fabricmc.loom.util.mappings.MojangMappingsDependency;
 
 public class LoomGradleExtension {
 	public String runDir = "run";
@@ -105,6 +106,10 @@ public class LoomGradleExtension {
 		return srcMercuryCache[id] != null ? srcMercuryCache[id] : (srcMercuryCache[id] = factory.get());
 	}
 
+	public Dependency officialMojangMappings() {
+		return new MojangMappingsDependency(project, this);
+	}
+
 	public LoomGradleExtension(Project project) {
 		this.project = project;
 		this.autoGenIDERuns = AbstractPlugin.isRootProject(project);

src/main/java/net/fabricmc/loom/providers/MappingsProvider.java

@@ -66,8 +66,10 @@ public class MappingsProvider extends DependencyProvider {
 	public String minecraftVersion;
 	public String mappingsVersion;
 
-	private Path mappingsDir;
+	private final Path mappingsDir;
-	private Path mappingsStepsDir;
+	private final Path mappingsStepsDir;
+	private Path intermediaryTiny;
+	private boolean hasRefreshed = false;
 	// The mappings that gradle gives us
 	private Path baseTinyMappings;
 	// The mappings we use in practice
@@ -77,6 +79,8 @@ public class MappingsProvider extends DependencyProvider {
 
 	public MappingsProvider(Project project) {
 		super(project);
+		mappingsDir = getExtension().getUserCache().toPath().resolve("mappings");
+		mappingsStepsDir = mappingsDir.resolve("steps");
 	}
 
 	public void clean() throws IOException {
@@ -172,14 +176,7 @@ public class MappingsProvider extends DependencyProvider {
 
 		if (baseMappingsAreV2()) {
 			// These are unmerged v2 mappings
-
+			mergeAndSaveMappings(project, yarnJar);
-			// Download and extract intermediary
-			String encodedMinecraftVersion = UrlEscapers.urlFragmentEscaper().escape(minecraftVersion);
-			String intermediaryArtifactUrl = getExtension().getIntermediaryUrl().apply(encodedMinecraftVersion);
-			Path intermediaryJar = mappingsStepsDir.resolve("v2-intermediary-" + minecraftVersion + ".jar");
-			DownloadUtil.downloadIfChanged(new URL(intermediaryArtifactUrl), intermediaryJar.toFile(), project.getLogger());
-
-			mergeAndSaveMappings(project, intermediaryJar, yarnJar);
 		} else {
 			// These are merged v1 mappings
 			if (tinyMappings.exists()) {
@@ -216,14 +213,15 @@ public class MappingsProvider extends DependencyProvider {
 		Files.copy(jar.getPath("mappings/mappings.tiny"), extractTo, StandardCopyOption.REPLACE_EXISTING);
 	}
 
-	private void mergeAndSaveMappings(Project project, Path unmergedIntermediaryJar, Path unmergedYarnJar) throws IOException {
+	private void extractIntermediary(Path intermediaryJar, Path intermediaryTiny) throws IOException {
-		Path unmergedIntermediary = Paths.get(mappingsStepsDir.toString(), "unmerged-intermediary.tiny");
+		getProject().getLogger().info(":extracting " + intermediaryJar.getFileName());
-		project.getLogger().info(":extracting " + unmergedIntermediaryJar.getFileName());
 
-		try (FileSystem unmergedIntermediaryFs = FileSystems.newFileSystem(unmergedIntermediaryJar, (ClassLoader) null)) {
+		try (FileSystem unmergedIntermediaryFs = FileSystems.newFileSystem(intermediaryJar, (ClassLoader) null)) {
-			extractMappings(unmergedIntermediaryFs, unmergedIntermediary);
+			extractMappings(unmergedIntermediaryFs, intermediaryTiny);
+		}
 	}
 
+	private void mergeAndSaveMappings(Project project, Path unmergedYarnJar) throws IOException {
 		Path unmergedYarn = Paths.get(mappingsStepsDir.toString(), "unmerged-yarn.tiny");
 		project.getLogger().info(":extracting " + unmergedYarnJar.getFileName());
 
@@ -232,7 +230,7 @@ public class MappingsProvider extends DependencyProvider {
 		}
 
 		Path invertedIntermediary = Paths.get(mappingsStepsDir.toString(), "inverted-intermediary.tiny");
-		reorderMappings(unmergedIntermediary, invertedIntermediary, "intermediary", "official");
+		reorderMappings(getIntermediaryTiny(), invertedIntermediary, "intermediary", "official");
 		Path unorderedMergedMappings = Paths.get(mappingsStepsDir.toString(), "unordered-merged.tiny");
 		project.getLogger().info(":merging");
 		mergeMappings(invertedIntermediary, unmergedYarn, unorderedMergedMappings);
@@ -277,9 +275,6 @@ public class MappingsProvider extends DependencyProvider {
 	}
 
 	private void initFiles() {
-		mappingsDir = getExtension().getUserCache().toPath().resolve("mappings");
-		mappingsStepsDir = mappingsDir.resolve("steps");
-
 		baseTinyMappings = mappingsDir.resolve(mappingsName + "-tiny-" + minecraftVersion + "-" + mappingsVersion + "-base");
 		mappingsMixinExport = new File(getExtension().getProjectBuildCache(), "mixin-map-" + minecraftVersion + "-" + mappingsVersion + ".tiny");
 	}
@@ -312,4 +307,30 @@ public class MappingsProvider extends DependencyProvider {
 	public String getTargetConfig() {
 		return Constants.MAPPINGS;
 	}
+
+	public Path getMappingsDir() {
+		return mappingsDir;
+	}
+
+	public Path getIntermediaryTiny() throws IOException {
+		if (intermediaryTiny == null) {
+			intermediaryTiny = Paths.get(mappingsStepsDir.toString(), String.format("intermediary-%s%s.tiny", minecraftVersion, mappingsVersion));
+
+			if (!Files.exists(intermediaryTiny) || (isRefreshDeps() && !hasRefreshed)) {
+				hasRefreshed = true;
+
+				minecraftVersion = getExtension().getMinecraftProvider().getMinecraftVersion();
+
+				// Download and extract intermediary
+				String encodedMinecraftVersion = UrlEscapers.urlFragmentEscaper().escape(minecraftVersion);
+				String intermediaryArtifactUrl = getExtension().getIntermediaryUrl().apply(encodedMinecraftVersion);
+				Path intermediaryJar = mappingsDir.resolve("v2-intermediary-" + minecraftVersion + ".jar");
+				DownloadUtil.downloadIfChanged(new URL(intermediaryArtifactUrl), intermediaryJar.toFile(), getProject().getLogger());
+
+				extractIntermediary(intermediaryJar, intermediaryTiny);
+			}
+		}
+
+		return intermediaryTiny;
+	}
 }

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

@@ -43,6 +43,7 @@ import org.gradle.api.GradleException;
 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.tasks.TaskAction;
 import org.gradle.api.tasks.options.Option;
@@ -51,6 +52,7 @@ import net.fabricmc.loom.LoomGradleExtension;
 import net.fabricmc.loom.providers.MappingsProvider;
 import net.fabricmc.loom.providers.MinecraftMappedProvider;
 import net.fabricmc.loom.util.SourceRemapper;
+import net.fabricmc.loom.util.mappings.MojangMappingsDependency;
 import net.fabricmc.lorenztiny.TinyMappingsJoiner;
 import net.fabricmc.mapping.tree.TinyMappingFactory;
 import net.fabricmc.mapping.tree.TinyTree;
@@ -116,7 +118,16 @@ public class MigrateMappingsTask extends AbstractLoomTask {
 		Set<File> files;
 
 		try {
-			files = project.getConfigurations().detachedConfiguration(project.getDependencies().create(mappings)).resolve();
+			if (mappings.startsWith("net.mojang.minecraft:mappings:")) {
+				if (!mappings.endsWith(":" + project.getExtensions().getByType(LoomGradleExtension.class).getMinecraftProvider().getMinecraftVersion())) {
+					throw new UnsupportedOperationException("Migrating Mojang mappings is currently only supported for the specified minecraft version");
+				}
+
+				files = new MojangMappingsDependency(project, getExtension()).resolve();
+			} else {
+				Dependency dependency = project.getDependencies().create(mappings);
+				files = project.getConfigurations().detachedConfiguration(dependency).resolve();
+			}
 		} catch (IllegalDependencyNotation ignored) {
 			project.getLogger().info("Could not locate mappings, presuming V2 Yarn");
 

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

@@ -133,6 +133,10 @@ public abstract class DependencyProvider {
 		}
 
 		public Set<File> resolve() {
+			if (dependency instanceof SelfResolvingDependency) {
+				return ((SelfResolvingDependency) dependency).resolve();
+			}
+
 			return sourceConfiguration.files(dependency);
 		}
 

src/main/java/net/fabricmc/loom/util/mappings/MojangMappingsDependency.java

@@ -0,0 +1,268 @@
+/*
+ * This file is part of fabric-loom, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) 2016, 2017, 2018 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.util.mappings;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Collections;
+import java.util.Set;
+import java.util.function.Consumer;
+
+import org.cadixdev.lorenz.MappingSet;
+import org.cadixdev.lorenz.io.TextMappingsWriter;
+import org.cadixdev.lorenz.io.proguard.ProGuardReader;
+import org.cadixdev.lorenz.model.ClassMapping;
+import org.cadixdev.lorenz.model.FieldMapping;
+import org.cadixdev.lorenz.model.InnerClassMapping;
+import org.cadixdev.lorenz.model.MethodMapping;
+import org.cadixdev.lorenz.model.TopLevelClassMapping;
+import org.gradle.api.Project;
+import org.gradle.api.artifacts.Dependency;
+import org.gradle.api.artifacts.SelfResolvingDependency;
+import org.gradle.api.tasks.TaskDependency;
+import org.zeroturnaround.zip.ByteSource;
+import org.zeroturnaround.zip.ZipEntrySource;
+import org.zeroturnaround.zip.ZipUtil;
+
+import net.fabricmc.loom.LoomGradleExtension;
+import net.fabricmc.loom.util.DownloadUtil;
+import net.fabricmc.loom.util.MinecraftVersionInfo;
+import net.fabricmc.lorenztiny.TinyMappingsReader;
+import net.fabricmc.mapping.tree.TinyMappingFactory;
+
+public class MojangMappingsDependency implements SelfResolvingDependency {
+	private final Project project;
+	private final LoomGradleExtension extension;
+
+	public MojangMappingsDependency(Project project, LoomGradleExtension extension) {
+		this.project = project;
+		this.extension = extension;
+	}
+
+	@Override
+	public Set<File> resolve() {
+		Path mappingsDir = extension.getMappingsProvider().getMappingsDir();
+		Path mappingsFile = mappingsDir.resolve(String.format("net.mojang.minecraft-mappings-%s.tiny", getVersion()));
+		Path clientMappings = mappingsDir.resolve(String.format("net.mojang.minecraft.mappings-%s-client.map", getVersion()));
+		Path serverMappings = mappingsDir.resolve(String.format("net.mojang.minecraft.mappings-%s-server.map", getVersion()));
+
+		if (!Files.exists(mappingsFile) || project.getGradle().getStartParameter().isRefreshDependencies()) {
+			MappingSet mappingSet;
+
+			try {
+				mappingSet = getMappingsSet(clientMappings, serverMappings);
+
+				try (Writer writer = new StringWriter()) {
+					new TinyWriter(writer, "intermediary", "named").write(mappingSet);
+					Files.deleteIfExists(mappingsFile);
+
+					ZipUtil.pack(new ZipEntrySource[] {
+							new ByteSource("mappings/mappings.tiny", writer.toString().getBytes(StandardCharsets.UTF_8))
+					}, mappingsFile.toFile());
+				}
+			} catch (IOException e) {
+				throw new RuntimeException("Failed to resolve Mojang mappings", e);
+			}
+		}
+
+		try (BufferedReader clientBufferedReader = Files.newBufferedReader(clientMappings, StandardCharsets.UTF_8)) {
+			project.getLogger().warn("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
+			project.getLogger().warn("Using of the official minecraft mappings is at your own risk!");
+			project.getLogger().warn("Please make sure to read and understand the following license:");
+			project.getLogger().warn("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
+			String line;
+
+			while ((line = clientBufferedReader.readLine()).startsWith("#")) {
+				project.getLogger().warn(line);
+			}
+
+			project.getLogger().warn("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
+		} catch (IOException e) {
+			throw new RuntimeException("Failed to read client mappings", e);
+		}
+
+		return Collections.singleton(mappingsFile.toFile());
+	}
+
+	private MappingSet getMappingsSet(Path clientMappings, Path serverMappings) throws IOException {
+		MinecraftVersionInfo versionInfo = extension.getMinecraftProvider().getVersionInfo();
+
+		if (versionInfo.downloads.get("client_mappings") == null) {
+			throw new RuntimeException("Failed to find official mojang mappings for " + getVersion());
+		}
+
+		String clientMappingsUrl = versionInfo.downloads.get("client_mappings").url;
+		String serverMappingsUrl = versionInfo.downloads.get("server_mappings").url;
+
+		DownloadUtil.downloadIfChanged(new URL(clientMappingsUrl), clientMappings.toFile(), project.getLogger());
+		DownloadUtil.downloadIfChanged(new URL(serverMappingsUrl), serverMappings.toFile(), project.getLogger());
+
+		MappingSet mappings = MappingSet.create();
+
+		try (BufferedReader clientBufferedReader = Files.newBufferedReader(clientMappings, StandardCharsets.UTF_8);
+				BufferedReader serverBufferedReader = Files.newBufferedReader(serverMappings, StandardCharsets.UTF_8)) {
+			try (ProGuardReader proGuardReaderClient = new ProGuardReader(clientBufferedReader);
+					ProGuardReader proGuardReaderServer = new ProGuardReader(serverBufferedReader)) {
+				proGuardReaderClient.read(mappings);
+				proGuardReaderServer.read(mappings);
+			}
+		}
+
+		MappingSet officialToNamed = mappings.reverse();
+		MappingSet intermediaryToOfficial;
+
+		try (BufferedReader reader = Files.newBufferedReader(extension.getMappingsProvider().getIntermediaryTiny(), StandardCharsets.UTF_8)) {
+			intermediaryToOfficial = new TinyMappingsReader(TinyMappingFactory.loadWithDetection(reader), "intermediary", "official").read();
+		}
+
+		MappingSet intermediaryToMojang = MappingSet.create();
+
+		// Merging. Don't use MappingSet#merge
+		iterateClasses(intermediaryToOfficial, inputMappings -> {
+			officialToNamed.getClassMapping(inputMappings.getFullDeobfuscatedName())
+					.ifPresent(namedClass -> {
+						ClassMapping<?, ?> mojangClassMapping = intermediaryToMojang.getOrCreateClassMapping(inputMappings .getFullObfuscatedName())
+								.setDeobfuscatedName(namedClass.getFullDeobfuscatedName());
+
+						for (FieldMapping fieldMapping : inputMappings .getFieldMappings()) {
+							namedClass.getFieldMapping(fieldMapping.getDeobfuscatedName())
+									.ifPresent(namedField -> {
+										mojangClassMapping.getOrCreateFieldMapping(fieldMapping.getSignature())
+												.setDeobfuscatedName(namedField.getDeobfuscatedName());
+									});
+						}
+
+						for (MethodMapping methodMapping : inputMappings .getMethodMappings()) {
+							namedClass.getMethodMapping(methodMapping.getDeobfuscatedSignature())
+									.ifPresent(namedMethod -> {
+										mojangClassMapping.getOrCreateMethodMapping(methodMapping.getSignature())
+												.setDeobfuscatedName(namedMethod.getDeobfuscatedName());
+									});
+						}
+					});
+		});
+
+		return intermediaryToMojang;
+	}
+
+	@Override
+	public Set<File> resolve(boolean transitive) {
+		return resolve();
+	}
+
+	@Override
+	public TaskDependency getBuildDependencies() {
+		return task -> Collections.emptySet();
+	}
+
+	@Override
+	public String getGroup() {
+		return "net.mojang.minecraft";
+	}
+
+	@Override
+	public String getName() {
+		return "mappings";
+	}
+
+	@Override
+	public String getVersion() {
+		return extension.getMinecraftProvider().getMinecraftVersion();
+	}
+
+	@Override
+	public boolean contentEquals(Dependency dependency) {
+		if (dependency instanceof MojangMappingsDependency) {
+			return ((MojangMappingsDependency) dependency).extension.getMinecraftProvider().getMinecraftVersion().equals(getVersion());
+		}
+
+		return false;
+	}
+
+	@Override
+	public Dependency copy() {
+		return new MojangMappingsDependency(project, extension);
+	}
+
+	@Override
+	public String getReason() {
+		return null;
+	}
+
+	@Override
+	public void because(String s) {
+	}
+
+	private static void iterateClasses(MappingSet mappings, Consumer<ClassMapping<?, ?>> consumer) {
+		for (TopLevelClassMapping classMapping : mappings.getTopLevelClassMappings()) {
+			iterateClass(classMapping, consumer);
+		}
+	}
+
+	private static void iterateClass(ClassMapping<?, ?> classMapping, Consumer<ClassMapping<?, ?>> consumer) {
+		consumer.accept(classMapping);
+
+		for (InnerClassMapping innerClassMapping : classMapping.getInnerClassMappings()) {
+			iterateClass(innerClassMapping, consumer);
+		}
+	}
+
+	private static class TinyWriter extends TextMappingsWriter {
+		private final String namespaceFrom;
+		private final String namespaceTo;
+
+		protected TinyWriter(Writer writer, String namespaceFrom, String namespaceTo) {
+			super(writer);
+			this.namespaceFrom = namespaceFrom;
+			this.namespaceTo = namespaceTo;
+		}
+
+		@Override
+		public void write(MappingSet mappings) {
+			writer.println("tiny\t2\t0\t" + namespaceFrom + "\t" + namespaceTo);
+
+			iterateClasses(mappings, classMapping -> {
+				writer.println("c\t" + classMapping.getFullObfuscatedName() + "\t" + classMapping.getFullDeobfuscatedName());
+
+				for (FieldMapping fieldMapping : classMapping.getFieldMappings()) {
+					fieldMapping.getType().ifPresent(fieldType -> {
+						writer.println("\tf\t" + fieldType + "\t" + fieldMapping.getObfuscatedName() + "\t" + fieldMapping.getDeobfuscatedName());
+					});
+				}
+
+				for (MethodMapping methodMapping : classMapping.getMethodMappings()) {
+					writer.println("\tm\t" + methodMapping.getSignature().getDescriptor() + "\t" + methodMapping.getObfuscatedName() + "\t" + methodMapping.getDeobfuscatedName());
+				}
+			});
+		}
+	}
+}