Add @keep and "Keep everything"

Keep everything will decide whether R8 should keep all public
symbols by default. If unchecked, you can now use @keep to
choose what to keep.

build.gradle.kts

@@ -18,7 +18,7 @@ repositories {
     maven("https://packages.jetbrains.team/maven/p/kpm/public/")
 }
 
-version = "1.4.7"
+version = "1.5.0"
 val baseName = "Kotlin Explorer"
 
 kotlin {

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/Disassembly.kt

@@ -60,6 +60,7 @@ suspend fun buildAndRun(
 
             val path = directory.resolve("KotlinExplorer.kt")
             Files.writeString(path, source)
+            writeSupportFiles(directory)
 
             val kotlinc = KotlinCompiler(toolPaths, directory).compile(path)
 
@@ -101,7 +102,8 @@ suspend fun buildAndDisassemble(
     onOat: (CodeContent) -> Unit,
     onLogs: (AnnotatedString) -> Unit,
     onStatusUpdate: (String, Float) -> Unit,
-    optimize: Boolean
+    optimize: Boolean,
+    keepEverything: Boolean
 ) = coroutineScope {
     val ui = currentCoroutineContext()
 
@@ -117,6 +119,7 @@ suspend fun buildAndDisassemble(
 
             val path = directory.resolve("KotlinExplorer.kt")
             Files.writeString(path, source)
+            writeSupportFiles(directory)
 
             val kotlinc = KotlinCompiler(toolPaths, directory).compile(path)
 
@@ -149,7 +152,7 @@ suspend fun buildAndDisassemble(
 
             val dexCompiler = DexCompiler(toolPaths, directory, r8rules)
 
-            val dex = dexCompiler.buildDex(optimize)
+            val dex = dexCompiler.buildDex(optimize, keepEverything)
 
             if (dex.exitCode != 0) {
                 updater.addJob(launch(ui) {
@@ -271,6 +274,36 @@ private fun cleanupClasses(directory: Path) {
         }
 }
 
+private fun writeSupportFiles(directory: Path) {
+    Files.writeString(
+        directory.resolve("Keep.kt"),
+        """
+import java.lang.annotation.ElementType.ANNOTATION_TYPE
+import java.lang.annotation.ElementType.CONSTRUCTOR
+import java.lang.annotation.ElementType.FIELD
+import java.lang.annotation.ElementType.METHOD
+import java.lang.annotation.ElementType.PACKAGE
+import java.lang.annotation.ElementType.TYPE
+
+@Retention(AnnotationRetention.BINARY)
+@Target(
+    AnnotationTarget.FILE,
+    AnnotationTarget.ANNOTATION_CLASS,
+    AnnotationTarget.CLASS,
+    AnnotationTarget.ANNOTATION_CLASS,
+    AnnotationTarget.CONSTRUCTOR,
+    AnnotationTarget.FUNCTION,
+    AnnotationTarget.PROPERTY_GETTER,
+    AnnotationTarget.PROPERTY_SETTER,
+    AnnotationTarget.FIELD
+)
+@Suppress("DEPRECATED_JAVA_ANNOTATION", "SupportAnnotationUsage")
+@java.lang.annotation.Target(PACKAGE, TYPE, ANNOTATION_TYPE, CONSTRUCTOR, METHOD, FIELD)
+public annotation class Keep 
+        """.trimIndent()
+    )
+}
+
 private fun showError(error: String) = buildAnnotatedString {
     withStyle(SpanStyle(ErrorColor)) {
         append(error)

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/KotlinExplorer.kt

@@ -37,6 +37,7 @@ import androidx.compose.ui.input.key.Key.Companion.C
 import androidx.compose.ui.input.key.Key.Companion.D
 import androidx.compose.ui.input.key.Key.Companion.F
 import androidx.compose.ui.input.key.Key.Companion.G
+import androidx.compose.ui.input.key.Key.Companion.K
 import androidx.compose.ui.input.key.Key.Companion.L
 import androidx.compose.ui.input.key.Key.Companion.O
 import androidx.compose.ui.input.key.Key.Companion.P
@@ -438,7 +439,8 @@ private fun FrameWindowScope.MainMenu(
                 onOatUpdate,
                 onLogsUpdate,
                 onStatusUpdate,
-                explorerState.optimize
+                explorerState.optimize,
+                explorerState.keepEverything
             )
         }
     }
@@ -508,6 +510,7 @@ private fun FrameWindowScope.MainMenu(
             )
             Separator()
             MenuCheckboxItem("Optimize with R8", CtrlShift(O), explorerState::optimize)
+            MenuCheckboxItem("Keep everything", CtrlShift(K), explorerState::keepEverything)
             MenuCheckboxItem("Build on Startup", shortcut = null, explorerState::autoBuildOnStartup)
             MenuItem(
                 "Build & Disassemble",

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/State.kt

@@ -28,6 +28,7 @@ import kotlin.io.path.readLines
 private const val AndroidHome = "ANDROID_HOME"
 private const val KotlinHome = "KOTLIN_HOME"
 private const val Optimize = "OPTIMIZE"
+private const val KeepEverything = "KEEP_EVERYTHING"
 private const val R8Rules = "R8_RULES"
 private const val AutoBuildOnStartup = "AUTO_BUILD_ON_STARTUP"
 private const val Presentation = "PRESENTATION"
@@ -55,6 +56,7 @@ class ExplorerState {
     var kotlinHome by StringState(KotlinHome, System.getenv("KOTLIN_HOME") ?: System.getProperty("user.home"))
     var toolPaths by mutableStateOf(createToolPaths())
     var optimize by BooleanState(Optimize, true)
+    var keepEverything by BooleanState(KeepEverything, true)
     var r8Rules by StringState(R8Rules, "")
     var autoBuildOnStartup by BooleanState(AutoBuildOnStartup, false)
     var presentationMode by BooleanState(Presentation, false)
@@ -151,5 +153,12 @@ private fun readSettings(file: Path): MutableMap<String, String> {
 private fun readSourceCode(toolPaths: ToolPaths) = if (toolPaths.sourceFile.exists()) {
     Files.readString(toolPaths.sourceFile)
 } else {
-    "fun square(a: Int): Int {\n    return a * a\n}\n"
+    """
+    // NOTE: If Build > Keep everything is *not* checked, used the @Keep
+    // annotation to keep the classes/methods/etc. you want to disassemble
+    fun square(a: Int): Int {
+        return a * a
+    }
+
+    """.trimIndent()
 }

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/build/DexCompiler.kt

@@ -16,14 +16,17 @@
 
 package dev.romainguy.kotlin.explorer.build
 
+import dev.romainguy.kotlin.explorer.ProcessResult
 import dev.romainguy.kotlin.explorer.ToolPaths
 import dev.romainguy.kotlin.explorer.process
 import java.nio.file.Files
 import java.nio.file.Path
 import kotlin.io.path.*
 
 class DexCompiler(private val toolPaths: ToolPaths, private val outputDirectory: Path, private val r8rules: String) {
-    suspend fun buildDex(optimize: Boolean) = process(*buildDexCommand(optimize), directory = outputDirectory)
+    suspend fun buildDex(optimize: Boolean, keepEverything: Boolean): ProcessResult {
+        return process(*buildDexCommand(optimize, keepEverything), directory = outputDirectory)
+    }
 
     suspend fun dumpDex() = process(
         toolPaths.dexdump.toString(),
@@ -33,8 +36,8 @@ class DexCompiler(private val toolPaths: ToolPaths, private val outputDirectory:
     )
 
     @OptIn(ExperimentalPathApi::class)
-    private fun buildDexCommand(optimize: Boolean): Array<String> {
-        writeR8Rules()
+    private fun buildDexCommand(optimize: Boolean, keepEverything: Boolean): Array<String> {
+        writeR8Rules(keepEverything)
 
         return buildList {
             add("java")
@@ -69,20 +72,47 @@ class DexCompiler(private val toolPaths: ToolPaths, private val outputDirectory:
         }.toTypedArray()
     }
 
-    private fun writeR8Rules() {
+    private fun writeR8Rules(keepEverything: Boolean) {
         // Match $ANDROID_HOME/tools/proguard/proguard-android-optimize.txt
         Files.writeString(
             outputDirectory.resolve("rules.txt"),
-            """
-                -optimizations !code/simplification/arithmetic,!code/simplification/cast,!field/*,!class/merging/*
-                -optimizationpasses 5
-                -allowaccessmodification
-                -dontpreverify
-                -dontobfuscate
-                -keep,allowoptimization class !kotlin.**,!kotlinx.** {
-                  <methods>;
+            buildString {
+                append(
+                    """
+                        -optimizations !code/simplification/arithmetic,!code/simplification/cast,!field/*,!class/merging/*
+                        -optimizationpasses 5
+                        -allowaccessmodification
+                        -dontpreverify
+                        -dontobfuscate
+                    """.trimIndent()
+                )
+                if (keepEverything) {
+                    append(
+                        """
+                        -keep,allowoptimization class !kotlin.**,!kotlinx.** {
+                            <methods >;
+                        }
+                        """.trimIndent()
+                    )
+                } else {
+                    append(
+                        """
+                        -keep,allowobfuscation @interface Keep
+                        -keep @Keep class * {*;}
+                        -keepclasseswithmembers class * {
+                            @Keep <methods>;
+                        }
+                        -keepclasseswithmembers class * {
+                            @Keep <fields>;
+                        }
+                        -keepclasseswithmembers class * {
+                            @Keep <init>(...);
+                        }
+                        """.trimIndent()
+                    )
                 }
-            """.trimIndent() + r8rules
+                append(r8rules)
+            }
         )
     }
 }

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/build/KolinCompiler.kt

@@ -27,13 +27,14 @@ class KotlinCompiler(private val toolPaths: ToolPaths, private val outputDirecto
     private fun buildCompileCommand(file: Path): Array<String> {
         val command = mutableListOf(
             toolPaths.kotlinc.toString(),
-            file.toString(),
             "-Xmulti-platform",
             "-Xno-param-assertions",
             "-Xno-call-assertions",
             "-Xno-receiver-assertions",
             "-classpath",
-            (toolPaths.kotlinLibs + listOf(toolPaths.platform)).joinToString(":") { jar -> jar.toString() }
+            (toolPaths.kotlinLibs + listOf(toolPaths.platform)).joinToString(":") { jar -> jar.toString() },
+            file.toString(),
+            file.parent.resolve("Keep.kt").toString()
         )
 
         return command.toTypedArray()