Refactor plugin tests (#158)

* Remove separate test plugin project & move to test projects

No file generation is needed anymore for our functional tests,
which will improve their execution time greatly. Also,
a cleaner way to separate different AGP environments is implemented.

* Remove old project from Circle CI config

* Add functional tests for Android Gradle Plugin 3.5.x

Author: Marcel Schnelle

.circleci/config.yml

@@ -7,7 +7,7 @@ defaults: &defaults
         GRADLE_OPTS: '-Dorg.gradle.jvmargs="-Xmx4g -XX:+HeapDumpOnOutOfMemoryError"'
 
 cache_key: &cache_key
-  key: jars-{{ checksum "build.gradle.kts" }}-{{ checksum "plugin/android-junit5/build.gradle.kts" }}-{{ checksum "plugin/android-junit5-tests/build.gradle.kts" }}-{{ checksum "instrumentation/api/build.gradle.kts" }}-{{ checksum "instrumentation/runner/build.gradle.kts" }}-{{ checksum "instrumentation/sample/build.gradle.kts" }}-{{ checksum "gradle/wrapper/gradle-wrapper.properties" }}-{{ checksum "buildSrc/src/main/kotlin/Artifacts.kt" }}-{{ checksum "buildSrc/src/main/kotlin/Libs.kt" }}-{{ checksum "buildSrc/src/main/kotlin/Versions.kt" }}
+  key: jars-{{ checksum "build.gradle.kts" }}-{{ checksum "plugin/android-junit5/build.gradle.kts" }}-{{ checksum "instrumentation/api/build.gradle.kts" }}-{{ checksum "instrumentation/runner/build.gradle.kts" }}-{{ checksum "instrumentation/sample/build.gradle.kts" }}-{{ checksum "gradle/wrapper/gradle-wrapper.properties" }}-{{ checksum "buildSrc/src/main/kotlin/Artifacts.kt" }}-{{ checksum "buildSrc/src/main/kotlin/Libs.kt" }}-{{ checksum "buildSrc/src/main/kotlin/Versions.kt" }}
 
 version: 2
 jobs:
@@ -23,14 +23,14 @@ jobs:
           command: cd plugin && ./gradlew :android-junit5:assemble --stacktrace --no-daemon
       - run:
           name: (Plugin) Test
-          command: cd plugin && ./gradlew :android-junit5-tests:check --stacktrace --no-daemon
+          command: cd plugin && ./gradlew :android-junit5:check --stacktrace --no-daemon
 
       - persist_to_workspace:
           root: ~/root
           paths:
             - project
       - store_artifacts:
-          path: plugin/android-junit5-tests/build/reports/tests/test
+          path: plugin/android-junit5/build/reports/tests/test
           destination: plugin
 
   build_instrumentation:

buildSrc/src/main/kotlin/Libs.kt

@@ -29,6 +29,14 @@ object Libs {
      * https://developer.android.com/studio */
     const val com_android_tools_build_gradle: String = "com.android.tools.build:gradle:" +
             Versions.com_android_tools_build_gradle
+    const val com_android_tools_build_gradle_32x: String = "com.android.tools.build:gradle:" +
+        Versions.com_android_tools_build_gradle_32x
+    const val com_android_tools_build_gradle_33x: String = "com.android.tools.build:gradle:" +
+        Versions.com_android_tools_build_gradle_33x
+    const val com_android_tools_build_gradle_34x: String = "com.android.tools.build:gradle:" +
+    Versions.com_android_tools_build_gradle_34x
+    const val com_android_tools_build_gradle_35x: String = "com.android.tools.build:gradle:" +
+        Versions.com_android_tools_build_gradle_35x
 
     /**
      * https://developer.android.com/studio */

buildSrc/src/main/kotlin/Tasks.kt

@@ -1,5 +1,4 @@
 import org.gradle.api.DefaultTask
-import org.gradle.api.file.FileCollection
 import org.gradle.api.tasks.InputFiles
 import org.gradle.api.tasks.OutputDirectory
 import org.gradle.api.tasks.TaskAction

buildSrc/src/main/kotlin/Utilities.kt

@@ -0,0 +1,40 @@
+import org.gradle.api.Project
+import org.gradle.api.tasks.compile.AbstractCompile
+
+fun Project.fixCompileTaskChain() {
+  setupCompileChain(
+      sourceCompileName = "compileKotlin",
+      targetCompileName = "compileGroovy",
+      javaCompileName = "compileJava",
+      classesTaskName = "classes")
+
+  setupCompileChain(
+      sourceCompileName = "compileTestGroovy",
+      targetCompileName = "compileTestKotlin",
+      javaCompileName = "compileTestJava",
+      classesTaskName = "testClasses")
+}
+
+/**
+ * @param sourceCompileName The sources in this task may call into the target
+ * @param targetCompileName The sources in this task must not call into the source
+ * @param javaCompileName Name of the neutral Java task
+ * @param classesTaskName Name of the neutral classes task
+ */
+private fun Project.setupCompileChain(sourceCompileName: String,
+                                      targetCompileName: String,
+                                      javaCompileName: String,
+                                      classesTaskName: String) {
+  val targetCompile = tasks.getByName(targetCompileName) as AbstractCompile
+  val sourceCompile = tasks.getByName(sourceCompileName) as AbstractCompile
+  val classesTask = tasks.getByName(classesTaskName)
+
+  logger.info("Remove dependency '$targetCompile' -> '$javaCompileName'")
+  targetCompile.dependsOn.remove(javaCompileName)
+
+  logger.info("Add dependency '$sourceCompile' -> '$targetCompile' (can call from left into right)")
+  sourceCompile.dependsOn.add(targetCompile)
+
+  sourceCompile.classpath += project.files(targetCompile.destinationDir)
+  classesTask.dependsOn.add(sourceCompile)
+}

buildSrc/src/main/kotlin/Versions.kt

@@ -16,6 +16,10 @@ object Versions {
     const val aapt2: String = "3.2.1-4818971" 
 
     const val com_android_tools_build_gradle: String = "3.4.0-rc02"
+    const val com_android_tools_build_gradle_32x: String = "3.2.1"
+    const val com_android_tools_build_gradle_33x: String = "3.3.2"
+    const val com_android_tools_build_gradle_34x: String = "3.4.0-rc02"
+    const val com_android_tools_build_gradle_35x: String = "3.5.0-alpha07"
 
     const val lint_gradle: String = "26.2.1"