Inital work on mixin prebaker, old code taken from fabric-base

build.gradle

@@ -54,6 +54,9 @@ dependencies {
 	shade 'cuchaz:enigma:0.11.0.+:lib'
 	shade 'net.fabricmc:tiny-remapper:+'
 
+	shade ('net.minecraft:launchwrapper:1.12') {
+		transitive = false
+	}
 
 	//Always fun when your dep needs the tool to build, but the tool needs the dep.
 	//compile 'net.fabricmc:fabric-base:16w38a-0.0.4-SNAPSHOT'

src/main/java/net/fabricmc/loom/util/proccessing/MixinPrebaker.java

@@ -0,0 +1,253 @@
+/*
+ * Copyright 2016 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package net.fabricmc.loom.util.proccessing;
+
+import com.google.common.base.Charsets;
+import com.google.common.io.ByteStreams;
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonObject;
+import net.minecraft.launchwrapper.Launch;
+import net.minecraft.launchwrapper.LaunchClassLoader;
+import org.objectweb.asm.*;
+import org.spongepowered.asm.launch.GlobalProperties;
+import org.spongepowered.asm.mixin.EnvironmentStateTweaker;
+import org.spongepowered.asm.mixin.transformer.MixinTransformer;
+import org.spongepowered.asm.service.mojang.MixinServiceLaunchWrapper;
+
+import javax.annotation.Nonnull;
+import java.io.*;
+import java.net.URLClassLoader;
+import java.nio.file.Files;
+import java.nio.file.attribute.FileTime;
+import java.time.Instant;
+import java.util.*;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.jar.JarInputStream;
+import java.util.jar.JarOutputStream;
+import java.util.stream.Collectors;
+import java.util.zip.ZipEntry;
+
+/**
+ * The purpose of this class is to provide an utility for baking mixins from
+ * mods into a JAR file at compile time to make accessing APIs provided by them
+ * more intuitive in development environment.
+ */
+public class MixinPrebaker {
+	private static class DesprinklingFieldVisitor extends FieldVisitor {
+		public DesprinklingFieldVisitor(int api, FieldVisitor fv) {
+			super(api, fv);
+		}
+
+		@Override
+		public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
+			if (isSprinkledAnnotation(desc)) {
+				return null;
+			}
+			return super.visitAnnotation(desc, visible);
+		}
+	}
+
+	private static class DesprinklingMethodVisitor extends MethodVisitor {
+		public DesprinklingMethodVisitor(int api, MethodVisitor mv) {
+			super(api, mv);
+		}
+
+		@Override
+		public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
+			if (isSprinkledAnnotation(desc)) {
+				return null;
+			}
+			return super.visitAnnotation(desc, visible);
+		}
+	}
+
+	private static class DesprinklingClassVisitor extends ClassVisitor {
+		public DesprinklingClassVisitor(int api, ClassVisitor cv) {
+			super(api, cv);
+		}
+
+		@Override
+		public FieldVisitor visitField(int access, String name, String desc, String signature, Object value) {
+			return new DesprinklingFieldVisitor(Opcodes.ASM5, super.visitField(access, name, desc, signature, value));
+		}
+
+		@Override
+		public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
+			return new DesprinklingMethodVisitor(Opcodes.ASM5, super.visitMethod(access, name, desc, signature, exceptions));
+		}
+
+		@Override
+		public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
+			if (isSprinkledAnnotation(desc)) {
+				return null;
+			}
+			return super.visitAnnotation(desc, visible);
+		}
+	}
+
+	private static boolean isSprinkledAnnotation(String desc) {
+		//System.out.println(desc);
+		return desc.startsWith("Lorg/spongepowered/asm/mixin/transformer/meta");
+	}
+
+	// Term proposed by Mumfrey, don't blame me
+	public static byte[] desprinkle(byte[] cls) {
+		ClassReader reader = new ClassReader(cls);
+		ClassWriter writer = new ClassWriter(0);
+
+		reader.accept(new DesprinklingClassVisitor(Opcodes.ASM5, writer), 0);
+		return writer.toByteArray();
+	}
+
+	public static final String APPLIED_MIXIN_CONFIGS_FILENAME = ".oml-applied-mixin-configs";
+	public static final String MAPPINGS_FILENAME = ".oml-dev-mappings.tiny";
+
+	public static void main(String[] args) {
+		boolean hasMappingsFile = false;
+
+		if (args.length < 3) {
+			System.out.println("usage: MixinPrebaker [-m mapping-file] <input-jar> <output-jar> <mod-jars...>");
+			return;
+		}
+
+		File mappingsFile = null;
+		int argOffset;
+		for (argOffset = 0; argOffset < args.length; argOffset++) {
+			if ("-m".equals(args[argOffset])) {
+				hasMappingsFile = true;
+				mappingsFile = new File(args[++argOffset]);
+				//TODO this is prob what was handling the mixin remmapping, this may need to be added back
+				//FabricMixinBootstrap.setMappingFile();
+			} else {
+				break;
+			}
+		}
+
+		Set<File> modFiles = new HashSet<>();
+		for (int i = argOffset + 2; i < args.length; i++) {
+			modFiles.add(new File(args[i]));
+		}
+
+		URLClassLoader ucl = (URLClassLoader) MixinPrebaker.class.getClassLoader();
+		Launch.classLoader = new LaunchClassLoader(ucl.getURLs());
+		Launch.blackboard = new HashMap<>();
+		Launch.blackboard.put(MixinServiceLaunchWrapper.BLACKBOARD_KEY_TWEAKS, Collections.emptyList());
+
+		List<JsonObject> modInfo = findModInfo(modFiles);
+		List<JsonObject> mods = new ArrayList<>();
+		for(JsonObject modInfoJson : modInfo){
+			if(!modInfoJson.isJsonArray()){
+				continue;
+			}
+			JsonArray jsonArray = modInfoJson.getAsJsonArray();
+			for (int i = 0; i < jsonArray.size(); i++) {
+				mods.add(jsonArray.get(i).getAsJsonObject());
+			}
+		}
+		List<String> mixins = new ArrayList<>();
+		for(JsonObject modObject : mods){
+			mixins.addAll(findMixins(modObject.getAsJsonArray("mixins")));
+			mixins.addAll(findMixins(modObject.getAsJsonArray("clientMixins")));
+			mixins.addAll(findMixins(modObject.getAsJsonArray("serverMixins")));
+		}
+		System.out.println("Found " + mixins.size() + " mixins to pre bake");
+
+		EnvironmentStateTweaker tweaker = new EnvironmentStateTweaker();
+		tweaker.getLaunchArguments();
+		tweaker.injectIntoClassLoader(Launch.classLoader);
+
+		MixinTransformer mixinTransformer = GlobalProperties.get(GlobalProperties.Keys.TRANSFORMER);
+
+		try {
+			JarInputStream input = new JarInputStream(new FileInputStream(new File(args[argOffset + 0])));
+			JarOutputStream output = new JarOutputStream(new FileOutputStream(new File(args[argOffset + 1])));
+			JarEntry entry;
+			while ((entry = input.getNextJarEntry()) != null) {
+				if (entry.getName().equals(APPLIED_MIXIN_CONFIGS_FILENAME)) {
+					continue;
+				}
+
+				if (hasMappingsFile && entry.getName().equals(MAPPINGS_FILENAME)) {
+					continue;
+				}
+
+				if (entry.getName().endsWith(".class")) {
+					byte[] classIn = ByteStreams.toByteArray(input);
+					String className = entry.getName().substring(0, entry.getName().length() - 6).replace('/', '.');
+					byte[] classOut = mixinTransformer.transformClassBytes(className, className, classIn);
+					if (classIn != classOut) {
+						System.out.println("Transformed " + className);
+						classOut = desprinkle(classOut);
+					}
+					JarEntry newEntry = new JarEntry(entry.getName());
+					newEntry.setComment(entry.getComment());
+					newEntry.setSize(classOut.length);
+					newEntry.setLastModifiedTime(FileTime.from(Instant.now()));
+					output.putNextEntry(newEntry);
+					output.write(classOut);
+				} else {
+					output.putNextEntry(entry);
+					ByteStreams.copy(input, output);
+				}
+			}
+
+			output.putNextEntry(new JarEntry(APPLIED_MIXIN_CONFIGS_FILENAME));
+			output.write(String.join("\n", mixins).getBytes(Charsets.UTF_8));
+
+			if (hasMappingsFile) {
+				output.putNextEntry(new JarEntry(MAPPINGS_FILENAME));
+				Files.copy(mappingsFile.toPath(), output);
+			}
+
+			input.close();
+			output.close();
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		}
+	}
+
+	private static List<String> findMixins(JsonArray jsonArray){
+		if(jsonArray == null || jsonArray.size() == 0){
+			return Collections.emptyList();
+		}
+		List<String> mixinList = new ArrayList<>();
+		for (int i = 0; i < jsonArray.size(); i++) {
+			mixinList.add(jsonArray.get(i).getAsString());
+		}
+		return mixinList;
+	}
+
+	private static List<JsonObject> findModInfo(Set<File> mods){
+		return mods.stream().map(file -> {
+			try {
+				JarFile jar = new JarFile(file);
+				return readModInfoFromJar(jar);
+			} catch (IOException e) {
+				throw new RuntimeException("Failed to mod " + file.getName(), e);
+			}
+		}).collect(Collectors.toList());
+	}
+
+	private static JsonObject readModInfoFromJar(@Nonnull JarFile file) throws IOException {
+		Gson gson = new Gson();
+		ZipEntry entry = file.getEntry("mod.json");
+		if (entry == null)
+			return null;
+		return gson.fromJson(new InputStreamReader(file.getInputStream(entry)), JsonObject.class);
+	}
+}

src/main/java/net/fabricmc/loom/util/proccessing/PreBakeMixins.java

@@ -46,8 +46,7 @@ public class PreBakeMixins {
 		}
 		project.getLogger().lifecycle(":preBaking mixins");
 		ProcessModsTask.addFile(Constants.MINECRAFT_MAPPED_JAR.get(extension), this);
-		//LogManager.getFormatterLogger("test");
+		MixinPrebaker.main(args);
-	//	MixinPrebaker.main(args);
 	}
 
 }