Android Studio Integration: Attempt via bsp for Java android apps

example/android/javalib/1-hello-world/app/src/androidTest/java/com/helloworld/app/ExampleInstrumentedTest.java

@@ -5,6 +5,7 @@
 import android.content.Context;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import androidx.test.platform.app.InstrumentationRegistry;
+import com.helloworld.SampleLogic;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -20,5 +21,6 @@ public void useAppContext() {
     // Context of the app under test.
     Context appContext = InstrumentationRegistry.getInstrumentation().getTargetContext();
     assertEquals("com.helloworld.app", appContext.getPackageName());
+    assertEquals(32.0f, SampleLogic.textSize(), 0.0001f);
   }
 }

example/android/javalib/1-hello-world/app/src/main/java/com/helloworld/SampleLogic.java

@@ -1,6 +1,6 @@
 package com.helloworld;
 
-class SampleLogic {
+public class SampleLogic {
 
   public static float textSize() {
     return 32f;

example/android/javalib/1-hello-world/app/src/test/java/com/helloworld/ExampleUnitTest.java

@@ -2,6 +2,7 @@
 
 import static org.junit.Assert.*;
 
+import com.helloworld.app.R;
 import org.junit.Test;
 
 /**
@@ -12,6 +13,8 @@
 public class ExampleUnitTest {
   @Test
   public void textSize_isCorrect() {
+
     assertEquals(32f, SampleLogic.textSize(), 0.000001f);
+    assertEquals(0x7f010000, R.color.text_green);
   }
 }

example/android/javalib/1-hello-world/build.mill

@@ -12,7 +12,6 @@ package build
 import mill._, javalib._
 
 import mill.javalib.android.{AndroidAppModule, AndroidSdkModule}
-import coursier.maven.MavenRepository
 import mill.javalib.android.AndroidTestModule
 
 // Create and configure an Android SDK module to manage Android SDK paths and tools.
@@ -107,7 +106,7 @@ object app extends AndroidAppModule {
 /** Usage
 
 > ./mill show app.test
-...compiling 3 Java sources...
+...compiling 1 Java source...
 
 > cat out/app/test/test.dest/out.json
 ["",[{"fullyQualifiedName":"com.helloworld.ExampleUnitTest.textSize_isCorrect","selector":"com.helloworld.ExampleUnitTest.textSize_isCorrect","duration":...,"status":"Success"}]]

example/android/kotlinlib/1-hello-kotlin/app/src/androidTest/java/com/helloworld/app/ExampleInstrumentedTest.kt

@@ -2,6 +2,8 @@ package com.helloworld.app
 
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import androidx.test.platform.app.InstrumentationRegistry
+import com.helloworld.SampleLogic
+import com.helloworld.SampleLogicInKotlinDir
 import org.junit.Assert.*
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -18,5 +20,7 @@ class ExampleInstrumentedTest {
         // Context of the app under test.
         val appContext = InstrumentationRegistry.getInstrumentation().targetContext
         assertEquals("com.helloworld.app", appContext.packageName)
+        assertEquals(32f, SampleLogic.textSize(), 0.0001f)
+        assertEquals(64f, SampleLogicInKotlinDir.textSize(), 0.00001f)
     }
 }

example/android/kotlinlib/1-hello-kotlin/app/src/main/java/com/helloworld/app/MainActivity.kt

@@ -5,6 +5,7 @@ import android.os.Bundle
 import android.view.Gravity
 import android.view.ViewGroup.LayoutParams
 import android.widget.TextView
+import com.helloworld.SampleLogic
 
 class MainActivity : Activity() {
     override fun onCreate(savedInstanceState: Bundle?) {
@@ -17,7 +18,7 @@ class MainActivity : Activity() {
         textView.text = getString(R.string.hello_world)
 
         // Set text size
-        textView.textSize = 32f
+        textView.textSize = SampleLogic.textSize()
 
         // Center the text within the view
         textView.gravity = Gravity.CENTER

example/android/kotlinlib/1-hello-kotlin/build.mill

@@ -106,7 +106,7 @@ object app extends AndroidAppKotlinModule {
 /** Usage
 
 > ./mill show app.test
-...Compiling 5 Kotlin sources...
+...Compiling 2 Kotlin sources...
 
 > cat out/app/test/test.dest/out.json
 ["",[{"fullyQualifiedName":"com.helloworld.ExampleUnitTest.text_size_is_correct","selector":"com.helloworld.ExampleUnitTest.text_size_is_correct","duration":...,"status":"Success"},{"fullyQualifiedName":"com.helloworld.ExampleUnitTestInKotlinDir.kotlin_dir_text_size_is_correct","selector":"com.helloworld.ExampleUnitTestInKotlinDir.kotlin_dir_text_size_is_correct","duration":...,"status":"Success"}]]

example/android/kotlinlib/2-compose/build.mill

@@ -11,7 +11,6 @@ package build
 
 import mill._
 import kotlinlib._
-import coursier.{Repository, MavenRepository}
 import coursier.core.{MinimizedExclusions, ModuleName, Organization}
 import coursier.params.ResolutionParams
 import mill.kotlinlib.android.AndroidAppKotlinModule

kotlinlib/src/mill/kotlinlib/android/AndroidAppKotlinModule.scala

@@ -23,7 +23,7 @@ import mill.javalib.android.AndroidAppModule
 trait AndroidAppKotlinModule extends AndroidAppModule with KotlinModule { outer =>
 
   override def sources: T[Seq[PathRef]] =
-    super.sources() :+ PathRef(millSourcePath / "src/main/kotlin")
+    super[AndroidAppModule].sources() :+ PathRef(millSourcePath / "src/main/kotlin")
 
   override def kotlincOptions = super.kotlincOptions() ++ {
     if (androidEnableCompose()) {
@@ -54,7 +54,7 @@ trait AndroidAppKotlinModule extends AndroidAppModule with KotlinModule { outer
 
   trait AndroidAppKotlinTests extends AndroidAppTests with KotlinTests {
     override def sources: T[Seq[PathRef]] =
-      super.sources() :+ PathRef(outer.millSourcePath / "src/test/kotlin")
+      super[AndroidAppTests].sources() ++ Seq(PathRef(outer.millSourcePath / "src/test/kotlin"))
   }
 
   trait AndroidAppKotlinInstrumentedTests extends AndroidAppKotlinModule
@@ -64,6 +64,8 @@ trait AndroidAppKotlinModule extends AndroidAppModule with KotlinModule { outer
     override final def androidSdkModule = outer.androidSdkModule
 
     override def sources: T[Seq[PathRef]] =
-      super.sources() :+ PathRef(outer.millSourcePath / "src/androidTest/kotlin")
+      super[AndroidAppInstrumentedTests].sources() :+ PathRef(
+        outer.millSourcePath / "src/androidTest/kotlin"
+      )
   }
 }

scalalib/src/mill/javalib/android/AndroidAppBundle.scala

@@ -28,7 +28,7 @@ trait AndroidAppBundle extends AndroidAppModule with JavaModule {
    */
   def androidBundleZip: T[PathRef] = Task {
     val dexFile = androidDex().path
-    val resFile = androidResources().path / "res.apk"
+    val resFile = androidResources()._1.path / "res.apk"
     val baseDir = Task.dest / "base"
     val appDir = Task.dest / "app"
 

scalalib/src/mill/javalib/android/AndroidAppModule.scala

@@ -3,8 +3,9 @@ package mill.javalib.android
 import coursier.Repository
 import mill._
 import mill.scalalib._
-import mill.api.{Logger, PathRef}
-import mill.define.ModuleRef
+import mill.api.{Logger, PathRef, internal}
+import mill.define.{ModuleRef, Task}
+import mill.scalalib.bsp.BspBuildTarget
 import mill.testrunner.TestResult
 import mill.util.Jvm
 import os.RelPath
@@ -266,9 +267,20 @@ trait AndroidAppModule extends JavaModule {
    */
   override def resources: T[Seq[PathRef]] = Task {
     val libResFolders = androidUnpackArchives().flatMap(_.resources)
-    super.resources() ++ libResFolders :+ PathRef(millSourcePath / "src/main/res")
+    libResFolders :+ PathRef(millSourcePath / "src/main/res")
   }
 
+  @internal
+  override def bspCompileClasspath: T[Agg[UnresolvedPath]] = Task {
+    compileClasspath().map(_.path).map(UnresolvedPath.ResolvedPath(_))
+  }
+
+  @internal
+  override def bspBuildTarget: BspBuildTarget = super.bspBuildTarget.copy(
+    baseDirectory = Some(millSourcePath / "src/main"),
+    tags = Seq("application")
+  )
+
   /**
    * Replaces AAR files in classpath with their extracted JARs.
    */
@@ -278,29 +290,42 @@ trait AndroidAppModule extends JavaModule {
       super.resolvedRunIvyDeps().filter(_.path.ext == "jar")
     // TODO process metadata shipped with Android libs. It can have some rules with Target SDK, for example.
     // TODO support baseline profiles shipped with Android libs.
-    super.compileClasspath().filter(_.path.ext == "jar") ++ jarFiles
+    super.compileClasspath().filter(_.path.ext != "aar") ++ jarFiles
   }
 
   /**
    * Specifies AAPT options for Android resource compilation.
    */
   def androidAaptOptions: T[Seq[String]] = Task { Seq("--auto-add-overlay") }
 
+  def androidTransitiveResources: Target[Seq[PathRef]] = Task {
+    T.traverse(transitiveModuleCompileModuleDeps) { m =>
+      Task.Anon(m.resources())
+    }().flatten
+  }
+
   /**
    * Compiles Android resources and generates `R.java` and `res.apk`.
    *
-   * @return [[PathRef]] to the directory with application's `R.java` and `res.apk`.
+   * @return [[(PathRef, Seq[PathRef]]] to the directory with application's `R.java` and `res.apk` and a list
+   *         of the zip files containing the resource compiled files
    *
    * For more details on the aapt2 tool, refer to:
    * [[https://developer.android.com/tools/aapt2 aapt Documentation]]
    */
-  def androidResources: T[PathRef] = Task {
+  def androidResources: T[(PathRef, Seq[PathRef])] = Task {
     val rClassDir = T.dest / rClassDirName
     val compiledResDir = T.dest / compiledResourcesDirName
     os.makeDir(compiledResDir)
     val compiledResources = collection.mutable.Buffer[os.Path]()
 
-    for (resDir <- resources().map(_.path).filter(os.exists)) {
+    val transitiveResources = androidTransitiveResources().map(_.path).filter(os.exists)
+
+    val localResources = resources().map(_.path).filter(os.exists)
+
+    val allResources = localResources ++ transitiveResources
+
+    for (resDir <- allResources) {
       val segmentsSeq = resDir.segments.toSeq
       val libraryName = segmentsSeq.dropRight(1).last
       // if not directory, but file, it should have one of the possible extensions: .flata, .zip, .jar, .jack,
@@ -382,7 +407,7 @@ trait AndroidAppModule extends JavaModule {
 
     os.call(appLinkArgs)
 
-    PathRef(T.dest)
+    (PathRef(T.dest), compiledResources.toSeq.map(PathRef(_)))
   }
 
   /**
@@ -397,7 +422,7 @@ trait AndroidAppModule extends JavaModule {
    * the Android resource generation step.
    */
   override def generatedSources: T[Seq[PathRef]] = Task {
-    super.generatedSources() ++ Seq(androidResources()) ++ Seq(androidLibsRClasses())
+    Seq(PathRef(androidResources()._1.path / rClassDirName)) ++ androidLibsRClasses()
   }
 
   /**
@@ -406,12 +431,20 @@ trait AndroidAppModule extends JavaModule {
    * @return os.Path to the Generated DEX File Directory
    */
   def androidDex: T[PathRef] = Task {
+
+    val inheritedClassFiles = compileClasspath().map(_.path).filter(os.isDir)
+      .flatMap(os.walk(_))
+      .filter(os.isFile)
+      .filter(_.ext == "class")
+      .map(_.toString())
+
     val appCompiledFiles = os.walk(compile().classes.path)
       .filter(_.ext == "class")
-      .map(_.toString)
+      .map(_.toString) ++ inheritedClassFiles
 
     val libsJarFiles = compileClasspath()
       .filter(_ != androidSdkModule().androidJarPath())
+      .filter(_.path.ext == "jar")
       .map(_.path.toString())
 
     val proguardFile = T.dest / "proguard-rules.pro"
@@ -421,13 +454,14 @@ trait AndroidAppModule extends JavaModule {
       .flatMap(_.proguardRules)
       .map(p => os.read(p.path))
       .appendedAll(mainDexPlatformRules)
-      .appended(os.read(androidResources().path / "main-dex-rules.pro"))
+      .appended(os.read(androidResources()._1.path / "main-dex-rules.pro"))
       .mkString("\n")
     os.write(proguardFile, knownProguardRules)
 
     val d8ArgsBuilder = Seq.newBuilder[String]
 
     d8ArgsBuilder += androidSdkModule().d8Path().path.toString
+
     if (androidIsDebug()) {
       d8ArgsBuilder += "--debug"
     } else {
@@ -462,7 +496,7 @@ trait AndroidAppModule extends JavaModule {
   def androidUnsignedApk: T[PathRef] = Task {
     val unsignedApk = Task.dest / "app.unsigned.apk"
 
-    os.copy(androidResources().path / "res.apk", unsignedApk)
+    os.copy(androidResources()._1.path / "res.apk", unsignedApk)
     val dexFiles = os.walk(androidDex().path)
       .filter(_.ext == "dex")
       .map(os.zip.ZipSource.fromPath)
@@ -650,29 +684,33 @@ trait AndroidAppModule extends JavaModule {
     PathRef(signedApk)
   }
 
-  def androidLibsRClasses: T[PathRef] = Task {
+  def androidLibsRClasses: T[Seq[PathRef]] = Task {
     // TODO do this better
     // So we have application R.java class generated by aapt2 link, which includes IDs of app resources + libs resources.
     // But we also need to have R.java classes for libraries. The process below is quite hacky and inefficient, because:
     // * it will generate R.java for the library even library has no resources declared
     // * R.java will have not only resource ID from this library, but from other libraries as well. They should be stripped.
-    val mainRClassPath = os.walk(androidResources().path / rClassDirName)
+    val rClassDir = androidResources()._1.path / rClassDirName
+    val mainRClassPath = os.walk(rClassDir)
       .find(_.last == "R.java")
       .get
+
     val mainRClass = os.read(mainRClassPath)
     val libsPackages = androidUnpackArchives()
       .flatMap(_.manifest)
       .map(f => ((XML.loadFile(f.path.toIO) \\ "manifest").head \ "@package").head.toString())
 
-    for (libPackage <- libsPackages) {
-      val libRClassPath = T.dest / libPackage.split('.') / "R.java"
-      os.write(
+    val libClasses: Seq[PathRef] = for {
+      libPackage <- libsPackages
+      libRClassPath = T.dest / libPackage.split('.') / "R.java"
+      _ = os.write(
         libRClassPath,
         mainRClass.replaceAll("package .+;", s"package $libPackage;"),
         createFolders = true
       )
-    }
-    PathRef(T.dest)
+    } yield PathRef(libRClassPath)
+
+    libClasses :+ PathRef(mainRClassPath)
   }
 
   /**
@@ -1007,15 +1045,23 @@ trait AndroidAppModule extends JavaModule {
   trait AndroidAppTests extends JavaTests {
     private def testPath = parent.millSourcePath / "src/test"
 
-    override def sources: T[Seq[PathRef]] = parent.sources() :+ PathRef(testPath / "java")
+    override def sources: T[Seq[PathRef]] = Seq(PathRef(testPath / "java"))
+
+    override def resources: T[Seq[PathRef]] = Task.Sources(Seq(PathRef(testPath / "res")))
+
+    override def bspBuildTarget: BspBuildTarget = super.bspBuildTarget.copy(
+      baseDirectory = Some(testPath),
+      canTest = true
+    )
 
-    override def resources: T[Seq[PathRef]] = parent.resources() :+ PathRef(testPath / "res")
   }
 
   trait AndroidAppInstrumentedTests extends AndroidAppModule with AndroidTestModule {
     private def androidMainSourcePath = parent.millSourcePath
     private def androidTestPath = androidMainSourcePath / "src/androidTest"
 
+    override def moduleDeps: Seq[JavaModule] = Seq(parent)
+
     override def androidCompileSdk: T[Int] = parent.androidCompileSdk
     override def androidMinSdk: T[Int] = parent.androidMinSdk
     override def androidTargetSdk: T[Int] = parent.androidTargetSdk
@@ -1030,11 +1076,15 @@ trait AndroidAppModule extends JavaModule {
 
     override def androidEmulatorPort: String = parent.androidEmulatorPort
 
-    override def sources: T[Seq[PathRef]] = parent.sources() :+ PathRef(androidTestPath / "java")
+    override def sources: T[Seq[PathRef]] = Seq(PathRef(androidTestPath / "java"))
 
     /** The resources in res directories of both main source and androidTest sources */
-    override def resources: T[Seq[PathRef]] =
-      super.resources() ++ parent.resources() :+ PathRef(androidTestPath / "res")
+    override def resources: T[Seq[PathRef]] = Task.Sources {
+      val libResFolders = androidUnpackArchives().flatMap(_.resources)
+      libResFolders ++ Seq(PathRef(androidTestPath / "res"))
+    }
+
+    override def generatedSources: T[Seq[PathRef]] = Task.Sources(Seq.empty[PathRef])
 
     /* TODO on debug work, an AndroidManifest.xml with debug and instrumentation settings
      * will need to be created. Then this needs to point to the location of that debug
@@ -1095,6 +1145,13 @@ trait AndroidAppModule extends JavaModule {
 
     /** Builds the apk including the integration tests (e.g. from androidTest) */
     def androidInstantApk: T[PathRef] = androidApk
+
+    @internal
+    override def bspBuildTarget: BspBuildTarget = super[AndroidTestModule].bspBuildTarget.copy(
+      baseDirectory = Some(androidTestPath),
+      canRun = false
+    )
+
   }
 
 }

scalalib/src/mill/javalib/android/AndroidTestModule.scala

@@ -4,7 +4,7 @@ import mill.T
 import mill.scalalib.TestModule
 
 @mill.api.experimental
-trait AndroidTestModule extends TestModule
+trait AndroidTestModule extends TestModule {}
 
 @mill.api.experimental
 object AndroidTestModule {