feat!: Add patch annotation processor

This commit introduces an annotation processor for patches. Patches can use the `@Patch` instead of super constructor parameters.

BREAKING CHANGE: The manifest for patches has been removed, and the properties have been added to patches. Patches are now `OptionsContainer`. The `@Patch` annotation has been removed in favour of the `@Patch` annotation from the annotation processor.

gradle/libs.versions.toml

@@ -6,8 +6,12 @@ kotlin-test = "1.8.20-RC"
 kotlinx-coroutines-core = "1.7.1"
 multidexlib2 = "3.0.3.r2"
 smali = "3.0.3"
+symbol-processing-api = "1.9.0-1.0.11"
 xpp3 = "1.1.4c"
 binary-compatibility-validator = "0.13.2"
+kotlin-compile-testing-ksp = "1.5.0"
+kotlinpoet-ksp = "1.14.2"
+ksp = "1.9.0-1.0.11"
 
 [libraries]
 android = { module = "com.google.android:android", version.ref = "android" }
@@ -17,7 +21,11 @@ kotlin-test = { module = "org.jetbrains.kotlin:kotlin-test", version.ref = "kotl
 kotlinx-coroutines-core = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version.ref = "kotlinx-coroutines-core" }
 multidexlib2 = { module = "app.revanced:multidexlib2", version.ref = "multidexlib2" }
 smali = { module = "com.android.tools.smali:smali", version.ref = "smali" }
+symbol-processing-api = { module = "com.google.devtools.ksp:symbol-processing-api", version.ref = "symbol-processing-api" }
 xpp3 = { module = "xpp3:xpp3", version.ref = "xpp3" }
+kotlin-compile-testing = { module = "com.github.tschuchortdev:kotlin-compile-testing-ksp", version.ref = "kotlin-compile-testing-ksp" }
+kotlinpoet-ksp = { module = "com.squareup:kotlinpoet-ksp", version.ref = "kotlinpoet-ksp" }
 
 [plugins]
 binary-compatibility-validator = { id = "org.jetbrains.kotlinx.binary-compatibility-validator", version.ref = "binary-compatibility-validator" }
+ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }

revanced-patch-annotations-processor/api/revanced-patch-annotations-processor.api

@@ -0,0 +1,25 @@
+public abstract interface annotation class app/revanced/patcher/patch/annotations/CompatiblePackage : java/lang/annotation/Annotation {
+	public abstract fun name ()Ljava/lang/String;
+	public abstract fun versions ()[Ljava/lang/String;
+}
+
+public abstract interface annotation class app/revanced/patcher/patch/annotations/Patch : java/lang/annotation/Annotation {
+	public abstract fun compatiblePackages ()[Lapp/revanced/patcher/patch/annotations/CompatiblePackage;
+	public abstract fun dependencies ()[Ljava/lang/Class;
+	public abstract fun description ()Ljava/lang/String;
+	public abstract fun name ()Ljava/lang/String;
+	public abstract fun requiresIntegrations ()Z
+	public abstract fun use ()Z
+}
+
+public final class app/revanced/patcher/patch/annotations/processor/PatchProcessor : com/google/devtools/ksp/processing/SymbolProcessor {
+	public fun <init> (Lcom/google/devtools/ksp/processing/CodeGenerator;Lcom/google/devtools/ksp/processing/KSPLogger;)V
+	public fun process (Lcom/google/devtools/ksp/processing/Resolver;)Ljava/util/List;
+}
+
+public final class app/revanced/patcher/patch/annotations/processor/PatchProcessorProvider : com/google/devtools/ksp/processing/SymbolProcessorProvider {
+	public fun <init> ()V
+	public fun create (Lcom/google/devtools/ksp/processing/SymbolProcessorEnvironment;)Lapp/revanced/patcher/patch/annotations/processor/PatchProcessor;
+	public synthetic fun create (Lcom/google/devtools/ksp/processing/SymbolProcessorEnvironment;)Lcom/google/devtools/ksp/processing/SymbolProcessor;
+}
+

revanced-patch-annotations-processor/build.gradle.kts

@@ -0,0 +1,50 @@
+plugins {
+    kotlin("jvm") version "1.9.0"
+    `maven-publish`
+    alias(libs.plugins.ksp)
+}
+
+group = "app.revanced"
+
+dependencies {
+    implementation(libs.symbol.processing.api)
+    implementation(libs.kotlinpoet.ksp)
+    implementation(project(":revanced-patcher"))
+
+    testImplementation(libs.kotlin.test)
+    testImplementation(libs.kotlin.compile.testing)
+}
+
+tasks {
+    test {
+        useJUnitPlatform()
+        testLogging {
+            events("PASSED", "SKIPPED", "FAILED")
+        }
+    }
+}
+
+kotlin { jvmToolchain(11) }
+
+java {
+    withSourcesJar()
+}
+
+publishing {
+    repositories {
+        mavenLocal()
+        maven {
+            name = "GitHubPackages"
+            url = uri("https://maven.pkg.github.com/revanced/revanced-patch-annotations-processor")
+            credentials {
+                username = System.getenv("GITHUB_ACTOR")
+                password = System.getenv("GITHUB_TOKEN")
+            }
+        }
+    }
+    publications {
+        create<MavenPublication>("gpr") {
+            from(components["java"])
+        }
+    }
+}

revanced-patch-annotations-processor/settings.gradle.kts

@@ -0,0 +1,2 @@
+rootProject.name = "revanced-patch-annotations-processor"
+

revanced-patch-annotations-processor/src/main/kotlin/app/revanced/patcher/patch/annotations/PatchAnnotations.kt

@@ -0,0 +1,38 @@
+package app.revanced.patcher.patch.annotations
+
+import java.lang.annotation.Inherited
+import kotlin.reflect.KClass
+
+/**
+ * Annotation for [app.revanced.patcher.patch.Patch] classes.
+ *
+ * @param name The name of the patch. If empty, the patch will be unnamed.
+ * @param description The description of the patch. If empty, no description will be used.
+ * @param dependencies The patches this patch depends on.
+ * @param compatiblePackages The packages this patch is compatible with.
+ * @param use Whether this patch should be used.
+ * @param requiresIntegrations Whether this patch requires integrations.
+ */
+@Retention(AnnotationRetention.SOURCE)
+@Target(AnnotationTarget.CLASS)
+@Inherited
+annotation class Patch(
+    val name: String = "",
+    val description: String = "",
+    val dependencies: Array<KClass<out app.revanced.patcher.patch.Patch<*>>> = [],
+    val compatiblePackages: Array<CompatiblePackage> = [],
+    val use: Boolean = true,
+    // TODO: Remove this property, once integrations are coupled with patches.
+    val requiresIntegrations: Boolean = false,
+)
+
+/**
+ * A package that a [app.revanced.patcher.patch.Patch] is compatible with.
+ *
+ * @param name The name of the package.
+ * @param versions The versions of the package.
+ */
+annotation class CompatiblePackage(
+    val name: String,
+    val versions: Array<String> = [],
+)

revanced-patch-annotations-processor/src/main/kotlin/app/revanced/patcher/patch/annotations/processor/PatchProcessor.kt

@@ -0,0 +1,198 @@
+package app.revanced.patcher.patch.annotations.processor
+
+import app.revanced.patcher.data.BytecodeContext
+import app.revanced.patcher.data.ResourceContext
+import app.revanced.patcher.patch.BytecodePatch
+import app.revanced.patcher.patch.PatchOptions
+import app.revanced.patcher.patch.ResourcePatch
+import app.revanced.patcher.patch.annotations.Patch
+import com.google.devtools.ksp.processing.*
+import com.google.devtools.ksp.symbol.KSAnnotated
+import com.google.devtools.ksp.symbol.KSAnnotation
+import com.google.devtools.ksp.symbol.KSClassDeclaration
+import com.google.devtools.ksp.symbol.KSType
+import com.google.devtools.ksp.validate
+import com.squareup.kotlinpoet.*
+import com.squareup.kotlinpoet.ksp.toClassName
+import com.squareup.kotlinpoet.ksp.writeTo
+import kotlin.reflect.KClass
+
+class PatchProcessor(
+    private val codeGenerator: CodeGenerator,
+    private val logger: KSPLogger
+) : SymbolProcessor {
+
+    private fun KSAnnotated.isSubclassOf(cls: KClass<*>): Boolean {
+        if (this !is KSClassDeclaration) return false
+
+        if (qualifiedName?.asString() == cls.qualifiedName) return true
+
+        return superTypes.any { it.resolve().declaration.isSubclassOf(cls) }
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    override fun process(resolver: Resolver): List<KSAnnotated> {
+        val executablePatches = buildMap {
+            resolver.getSymbolsWithAnnotation(Patch::class.qualifiedName!!).filter {
+                // Do not check here if Patch is super of the class, because it is expensive.
+                // Check it later when processing.
+                it.validate() && it.isSubclassOf(app.revanced.patcher.patch.Patch::class)
+            }.map {
+                it as KSClassDeclaration
+            }.forEach { patchDeclaration ->
+                patchDeclaration.annotations.find {
+                    it.annotationType.resolve().declaration.qualifiedName!!.asString() == Patch::class.qualifiedName!!
+                }?.let { annotation ->
+                    fun KSAnnotation.property(name: String) =
+                        arguments.find { it.name!!.asString() == name }?.value!!
+
+                    val name =
+                        annotation.property("name").toString().ifEmpty { null }
+
+                    val description =
+                        annotation.property("description").toString().ifEmpty { null }
+
+                    val dependencies =
+                        (annotation.property("dependencies") as List<KSType>).ifEmpty { null }
+
+                    val compatiblePackages =
+                        (annotation.property("compatiblePackages") as List<KSAnnotation>).ifEmpty { null }
+
+                    val use =
+                        annotation.property("use") as Boolean
+
+                    val requiresIntegrations =
+                        annotation.property("requiresIntegrations") as Boolean
+
+                    // Data class for KotlinPoet
+                    data class PatchData(
+                        val name: String?,
+                        val description: String?,
+                        val dependencies: List<ClassName>?,
+                        val compatiblePackages: List<CodeBlock>?,
+                        val use: Boolean,
+                        val requiresIntegrations: Boolean
+                    )
+
+                    this[patchDeclaration] = PatchData(
+                        name,
+                        description,
+                        dependencies?.map { dependency -> dependency.toClassName() },
+                        compatiblePackages?.map {
+                            val packageName = it.property("name")
+                            val packageVersions = (it.property("versions") as List<String>)
+                                .joinToString(", ") { version -> "\"$version\"" }
+
+                            CodeBlock.of(
+                                "%T(%S, setOf(%L))",
+                                app.revanced.patcher.patch.Patch.CompatiblePackage::class,
+                                packageName,
+                                packageVersions
+                            )
+                        },
+                        use,
+                        requiresIntegrations
+                    )
+                }
+            }
+        }
+
+        // If a patch depends on another, that is annotated, the dependency should be replaced with the generated patch,
+        // because the generated patch has all the necessary properties to invoke the super constructor,
+        // unlike the annotated patch.
+        val dependencyResolutionMap = buildMap {
+            executablePatches.values.filter { it.dependencies != null }.flatMap {
+                it.dependencies!!
+            }.distinct().forEach { dependency ->
+                executablePatches.keys.find { it.qualifiedName?.asString() == dependency.toString() }
+                    ?.let { patch ->
+                        this[dependency] = ClassName(
+                            patch.packageName.asString(),
+                            patch.simpleName.asString() + "Generated"
+                        )
+                    }
+            }
+        }
+
+        // kotlin poet generate a class for each patch
+        executablePatches.forEach { (patchDeclaration, patchAnnotation) ->
+            val isBytecodePatch = patchDeclaration.isSubclassOf(BytecodePatch::class)
+
+            val superClass = if (isBytecodePatch) {
+                BytecodePatch::class
+            } else {
+                ResourcePatch::class
+            }
+
+            val contextClass = if (isBytecodePatch) {
+                BytecodeContext::class
+            } else {
+                ResourceContext::class
+            }
+
+            val generatedPatchClassName = ClassName(
+                patchDeclaration.packageName.asString(),
+                patchDeclaration.simpleName.asString() + "Generated"
+            )
+
+            FileSpec.builder(generatedPatchClassName)
+                .addType(
+                    TypeSpec.objectBuilder(generatedPatchClassName)
+                        .superclass(superClass).apply {
+                            patchAnnotation.name?.let { name ->
+                                addSuperclassConstructorParameter("name = %S", name)
+                            }
+
+                            patchAnnotation.description?.let { description ->
+                                addSuperclassConstructorParameter("description = %S", description)
+                            }
+
+                            patchAnnotation.compatiblePackages?.let { compatiblePackages ->
+                                addSuperclassConstructorParameter(
+                                    "compatiblePackages = setOf(%L)",
+                                    compatiblePackages.joinToString(", ")
+                                )
+                            }
+
+                            patchAnnotation.dependencies?.let { dependencies ->
+                                addSuperclassConstructorParameter(
+                                    "dependencies = setOf(%L)",
+                                    buildList {
+                                        addAll(dependencies)
+                                        // Also add the source class of the generated class so that it is also executed
+                                        add(patchDeclaration.toClassName())
+                                    }.joinToString(", ") { dependency ->
+                                        "${(dependencyResolutionMap[dependency] ?: dependency)}::class"
+                                    }
+                                )
+                            }
+                            addSuperclassConstructorParameter(
+                                "use = %L", patchAnnotation.use
+                            )
+
+                            addSuperclassConstructorParameter(
+                                "requiresIntegrations = %L",
+                                patchAnnotation.requiresIntegrations
+                            )
+                        }
+                        .addFunction(
+                            FunSpec.builder("execute")
+                                .addModifiers(KModifier.OVERRIDE)
+                                .addParameter("context", contextClass)
+                                .build()
+                        )
+                        .addProperty(
+                            PropertySpec.builder("options", PatchOptions::class, KModifier.OVERRIDE)
+                                .initializer("%T.options", patchDeclaration.toClassName())
+                                .build()
+                        )
+                        .build()
+                ).build().writeTo(
+                    codeGenerator,
+                    Dependencies(false, patchDeclaration.containingFile!!)
+                )
+        }
+
+        return emptyList()
+    }
+}

revanced-patch-annotations-processor/src/main/kotlin/app/revanced/patcher/patch/annotations/processor/PatchProcessorProvider.kt

@@ -0,0 +1,9 @@
+package app.revanced.patcher.patch.annotations.processor
+
+import com.google.devtools.ksp.processing.SymbolProcessorEnvironment
+import com.google.devtools.ksp.processing.SymbolProcessorProvider
+
+class PatchProcessorProvider : SymbolProcessorProvider {
+    override fun create(environment: SymbolProcessorEnvironment) =
+        PatchProcessor(environment.codeGenerator, environment.logger)
+}

revanced-patch-annotations-processor/src/main/resources/META-INF/services/com.google.devtools.ksp.processing.SymbolProcessorProvider

@@ -0,0 +1 @@
+app.revanced.patcher.patch.annotations.processor.PatchProcessorProvider