Add preliminary plugin support

build.gradle

@@ -6,24 +6,49 @@ plugins {
 	id 'checkstyle'
 }
 
-checkstyle {
-	configFile = file('checkstyle.xml')
-}
+allprojects {
+	apply plugin: 'java-library'
+	apply plugin: 'maven-publish'
+	apply plugin: 'com.diffplug.spotless'
+	apply plugin: 'checkstyle'
 
-sourceCompatibility = JavaVersion.VERSION_1_8
-targetCompatibility = JavaVersion.VERSION_1_8
+	sourceCompatibility = JavaVersion.VERSION_1_8
+	targetCompatibility = JavaVersion.VERSION_1_8
 
-def ENV = System.getenv()
-version += (ENV.GITHUB_ACTIONS ? '' : '+local')
+	repositories {
+		mavenCentral()
+		maven {
+			name = 'Fabric'
+			url = 'https://maven.fabricmc.net/'
+		}
+	}
 
-repositories {
-	mavenCentral()
-	maven {
-		name = 'Fabric'
-		url = 'https://maven.fabricmc.net/'
+	checkstyle {
+		configFile = rootProject.file('checkstyle.xml')
+	}
+
+	spotless {
+		java {
+			licenseHeaderFile(rootProject.file('HEADER'))
+		}
+	}
+
+	java {
+		withSourcesJar()
+	}
+
+	tasks.withType(JavaCompile).configureEach {
+		it.options.encoding = 'UTF-8'
+
+		if (JavaVersion.current().isJava9Compatible()) {
+			it.options.release = 8
+		}
 	}
 }
 
+def ENV = System.getenv()
+version += (ENV.GITHUB_ACTIONS ? '' : '+local')
+
 configurations {
 	ship
 	implementation.extendsFrom ship
@@ -42,12 +67,6 @@ dependencies {
 	testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:${junit_jupiter_version}"
 }
 
-spotless {
-	java {
-		licenseHeaderFile(rootProject.file('HEADER'))
-	}
-}
-
 jar {
 	manifest {
 		attributes 'Implementation-Title': 'Stitch',
@@ -57,22 +76,10 @@ jar {
 }
 
 shadowJar {
-    configurations = [project.configurations.ship]
+	configurations = [project.configurations.ship]
 	archiveClassifier = 'all'
 }
 
-java {
-	withSourcesJar()
-}
-
-tasks.withType(JavaCompile).configureEach {
-	it.options.encoding = 'UTF-8'
-
-	if (JavaVersion.current().isJava9Compatible()) {
-		it.options.release = 8
-	}
-}
-
 publishing {
 	publications {
 		mavenJava(MavenPublication) {

minecraft-plugin/build.gradle

@@ -0,0 +1,30 @@
+archivesBaseName = 'stitch-minecraft-plugin'
+version = rootProject.version
+group = rootProject.group
+
+dependencies {
+	implementation project(':')
+}
+
+def ENV = System.getenv()
+
+publishing {
+	publications {
+		mavenJava(MavenPublication) {
+			from components.java
+		}
+	}
+
+	repositories {
+		if (ENV.MAVEN_URL) {
+			repositories.maven {
+				name 'fabric'
+				url ENV.MAVEN_URL
+				credentials {
+					username ENV.MAVEN_USERNAME
+					password ENV.MAVEN_PASSWORD
+				}
+			}
+		}
+	}
+}

minecraft-plugin/src/main/java/net/fabricmc/stitch/plugins/MinecraftPlugin.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 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.stitch.plugins;
+
+import java.util.regex.Pattern;
+
+import net.fabricmc.stitch.plugin.StitchPlugin;
+import net.fabricmc.stitch.representation.ClassStorage;
+import net.fabricmc.stitch.representation.JarClassEntry;
+import net.fabricmc.stitch.representation.JarFieldEntry;
+import net.fabricmc.stitch.representation.JarMethodEntry;
+
+public class MinecraftPlugin implements StitchPlugin {
+	// Minecraft classes without a package are obfuscated.
+	private static Pattern classObfuscationPattern = Pattern.compile("^[^/]*$");
+
+	@Override
+	public int needsIntermediaryName(ClassStorage storage, JarClassEntry cls) {
+		return StitchPlugin.super.needsIntermediaryName(storage, cls) > 0
+				&& classObfuscationPattern.matcher(cls.getName()).matches() ? 2 : -2;
+	}
+
+	@Override
+	public int needsIntermediaryName(ClassStorage storage, JarClassEntry cls, JarFieldEntry fld) {
+		String name = fld.getName();
+
+		return name.length() <= 2 || (name.length() == 3 && name.charAt(2) == '_') ? 2 : -2;
+	}
+
+	@Override
+	public int needsIntermediaryName(ClassStorage storage, JarClassEntry cls, JarMethodEntry mth) {
+		String name = mth.getName();
+
+		return (name.length() <= 2 || (name.length() == 3 && name.charAt(2) == '_'))
+				&& StitchPlugin.super.needsIntermediaryName(storage, cls, mth) > 0 ? 2 : -2;
+	}
+
+	@Override
+	public String getIntermediaryTargetPackage() {
+		return "net/minecraft/";
+	}
+}

minecraft-plugin/src/main/resources/META-INF/services/net.fabricmc.stitch.plugin.StitchPlugin

@@ -0,0 +1 @@
+net.fabricmc.stitch.plugin.StitchPlugin

settings.gradle

@@ -10,3 +10,5 @@ pluginManagement {
 }
 
 rootProject.name = 'stitch'
+
+include ':minecraft-plugin'

src/main/java/net/fabricmc/stitch/Main.java

@@ -28,6 +28,7 @@
 import net.fabricmc.stitch.commands.CommandRewriteIntermediary;
 import net.fabricmc.stitch.commands.CommandUpdateIntermediary;
 import net.fabricmc.stitch.commands.CommandValidateRecords;
+import net.fabricmc.stitch.plugin.PluginLoader;
 
 public class Main {
 	private static final Map<String, Command> COMMAND_MAP = new TreeMap<>();
@@ -72,6 +73,7 @@ public static void main(String[] args) {
 				System.arraycopy(args, 1, argsCommand, 0, argsCommand.length);
 			}
 
+			PluginLoader.loadPlugins();
 			COMMAND_MAP.get(args[0].toLowerCase(Locale.ROOT)).run(argsCommand);
 		} catch (Exception e) {
 			e.printStackTrace();

src/main/java/net/fabricmc/stitch/commands/CommandGenerateIntermediary.java

@@ -31,7 +31,7 @@ public CommandGenerateIntermediary() {
 
 	@Override
 	public String getHelpString() {
-		return "<input-jar> <mapping-name> [-t|--target-namespace <namespace>] [-p|--obfuscation-pattern <regex pattern>]...";
+		return "<input-jar> <mapping-name> [-t|--target-namespace <namespace>] [--write-all]";
 	}
 
 	@Override
@@ -52,7 +52,6 @@ public void run(String[] args) throws Exception {
 		}
 
 		GenState state = new GenState();
-		boolean clearedPatterns = false;
 
 		for (int i = 2; i < args.length; i++) {
 			switch (args[i].toLowerCase(Locale.ROOT)) {
@@ -61,15 +60,8 @@ public void run(String[] args) throws Exception {
 				state.setTargetPackage(args[i + 1]);
 				i++;
 				break;
-			case "-p":
-			case "--obfuscation-pattern":
-				if (!clearedPatterns) {
-					state.clearObfuscatedPatterns();
-				}
-
-				clearedPatterns = true;
-				state.addObfuscatedPattern(args[i + 1]);
-				i++;
+			case "--write-all":
+				state.setWriteAll(true);
 				break;
 			}
 		}

src/main/java/net/fabricmc/stitch/commands/CommandRewriteIntermediary.java

@@ -31,7 +31,7 @@ public CommandRewriteIntermediary() {
 
 	@Override
 	public String getHelpString() {
-		return "<jar> <old-mapping-file> <new-mapping-file> [--writeAll]";
+		return "<jar> <old-mapping-file> <new-mapping-file> [--write-all]";
 	}
 
 	@Override
@@ -55,7 +55,7 @@ public void run(String[] args) throws Exception {
 
 		for (int i = 3; i < args.length; i++) {
 			switch (args[i].toLowerCase(Locale.ROOT)) {
-			case "--writeall":
+			case "--write-all":
 				state.setWriteAll(true);
 				break;
 			}

src/main/java/net/fabricmc/stitch/commands/CommandUpdateIntermediary.java

@@ -31,7 +31,7 @@ public CommandUpdateIntermediary() {
 
 	@Override
 	public String getHelpString() {
-		return "<old-jar> <new-jar> <old-mapping-file> <new-mapping-file> <match-file> [-t|--target-namespace <namespace>] [-p|--obfuscation-pattern <regex pattern>]";
+		return "<old-jar> <new-jar> <old-mapping-file> <new-mapping-file> <match-file> [-t|--target-namespace <namespace>] [--write-all]";
 	}
 
 	@Override
@@ -62,7 +62,6 @@ public void run(String[] args) throws Exception {
 		}
 
 		GenState state = new GenState();
-		boolean clearedPatterns = false;
 
 		for (int i = 5; i < args.length; i++) {
 			switch (args[i].toLowerCase(Locale.ROOT)) {
@@ -71,15 +70,8 @@ public void run(String[] args) throws Exception {
 				state.setTargetPackage(args[i + 1]);
 				i++;
 				break;
-			case "-p":
-			case "--obfuscation-pattern":
-				if (!clearedPatterns) {
-					state.clearObfuscatedPatterns();
-				}
-
-				clearedPatterns = true;
-				state.addObfuscatedPattern(args[i + 1]);
-				i++;
+			case "--write-all":
+				state.setWriteAll(true);
 				break;
 			}
 		}