Introduce jacoco-centric functional tests & safely access its members for Gradle 4+ (#144)

Author: Marcel Schnelle

android-junit5-tests/build.gradle.kts

@@ -48,6 +48,14 @@ configurations {
     description = "Local dependencies used for compiling & running " +
         "tests source code in Gradle functional tests against AGP 3.4.X"
   }
+
+  create("functionalTestJacocoAgent") {
+    description = "Local dependencies used for using Jacoco Agent during Gradle functional tests"
+  }
+
+  create("functionalTestJacocoAnt") {
+    description = "Local dependencies used for using Jacoco Ant during Gradle functional tests"
+  }
 }
 
 val processTestResources = tasks.getByName("processTestResources") as Copy
@@ -102,6 +110,12 @@ dependencies {
   functionalTest(Libs.junit_jupiter_api)
   functionalTest(Libs.junit_jupiter_engine)
 
+  val functionalTestJacocoAgent by configurations
+  functionalTestJacocoAgent(Libs.org_jacoco_agent)
+
+  val functionalTestJacocoAnt by configurations
+  functionalTestJacocoAnt(Libs.org_jacoco_ant)
+
   val functionalTestAgp32X by configurations
   functionalTestAgp32X("com.android.tools.build:gradle:3.2.1")
 
@@ -120,7 +134,13 @@ tasks.create("writePluginClasspath", WriteClasspathResource::class) {
 }
 
 // Create a classpath-generating task for all functional test configurations
-listOf("functionalTest", "functionalTestAgp32X", "functionalTestAgp33X", "functionalTestAgp34X").forEach { config ->
+listOf(
+        "functionalTest",
+        "functionalTestJacocoAnt",
+        "functionalTestJacocoAgent",
+        "functionalTestAgp32X",
+        "functionalTestAgp33X",
+        "functionalTestAgp34X").forEach { config ->
   tasks.create("write${config.capitalize()}CompileClasspath", WriteClasspathResource::class) {
     inputFiles = configurations[config]
     outputDir = File("$buildDir/resources/test")

android-junit5-tests/src/test/kotlin/de/mannodermaus/gradle/plugins/junit5/FunctionalTests.kt

@@ -7,6 +7,7 @@ import de.mannodermaus.gradle.plugins.junit5.util.FileLanguage2.Java
 import de.mannodermaus.gradle.plugins.junit5.util.FileLanguage2.Kotlin
 import org.gradle.testkit.runner.BuildResult
 import org.gradle.testkit.runner.GradleRunner
+import org.gradle.testkit.runner.TaskOutcome
 import org.junit.jupiter.api.DynamicTest.dynamicTest
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.TestFactory
@@ -52,6 +53,10 @@ class FunctionalTests {
 
   // Classpath of the main "functionalTest" configuration
   private lateinit var functionalTestFiles: List<File>
+  // Classpath of the main "functionalTestJacocoAnt" configuration
+  private lateinit var functionalTestJacocoAntFiles: List<File>
+  // Classpath of the main "functionalTestJacocoAgent" configuration
+  private lateinit var functionalTestJacocoAgentFiles: List<File>
   // Classpath of the specialized "functionalTestAgpX" configuration
   private lateinit var functionalTestSpecialFiles: List<File>
 
@@ -67,6 +72,10 @@ class FunctionalTests {
     this.pluginFiles = loadClassPathManifestResource("plugin-classpath.txt")
     this.functionalTestFiles = loadClassPathManifestResource(
         "functionalTest-compile-classpath.txt")
+    this.functionalTestJacocoAntFiles = loadClassPathManifestResource(
+        "functionalTestJacocoAnt-compile-classpath.txt")
+    this.functionalTestJacocoAgentFiles = loadClassPathManifestResource(
+        "functionalTestJacocoAgent-compile-classpath.txt")
     this.functionalTestSpecialFiles = loadClassPathManifestResource(
         "$configName-compile-classpath.txt")
 
@@ -349,6 +358,33 @@ class FunctionalTests {
     }
   }
 
+  @TestFactory
+  fun `Configures Jacoco correctly`(@TempDir testProjectDir: Path) =
+      SUPPORTED_VARIATIONS
+          .map { variation ->
+            val (agpVersion, configName, gradleVersion) = variation
+            dynamicTest("Using AGP $agpVersion & Gradle $gradleVersion tests") {
+              val folder = testProjectDir.newFile("$gradleVersion-$agpVersion")
+              setupNewProject(folder, configName)
+              given {
+                plugins {
+                  android()
+                  jacoco()
+                  junit5()
+                }
+                testSources(Java) {
+                  test()
+                }
+              }
+
+              runGradle(version = gradleVersion, tasks = "jacocoTestReportDebug") { result ->
+                listOf(
+                    { assertThat(result).executedTaskWithOutcome(":testDebugUnitTest", TaskOutcome.SUCCESS) }
+                )
+              }
+            }
+          }
+
   /* Private */
 
   private fun loadClassPathManifestResource(name: String): List<File> {
@@ -371,7 +407,7 @@ class FunctionalTests {
     val buildResult = GradleRunner.create()
         .withProjectDir(testProjectDir)
         .withPluginClasspath(pluginFiles)
-        .withArguments(tasks)
+        .withArguments(tasks, "--stacktrace")
         .apply {
           if (version != null) {
             withGradleVersion(version)
@@ -502,6 +538,17 @@ class FunctionalTests {
           }
         """)
       }
+
+      fun jacoco() {
+        buildFile.appendText("""
+          apply plugin: "jacoco"
+
+          dependencies {
+            jacocoAnt files(${functionalTestJacocoAntFiles.splitClasspath()})
+            jacocoAgent files(${functionalTestJacocoAgentFiles.splitClasspath()})
+          }
+        """.trimIndent())
+      }
     }
 
     inner class TestSources(private val language: FileLanguage2) {

android-junit5-tests/src/test/kotlin/de/mannodermaus/gradle/plugins/junit5/util/TestExtensions.kt

@@ -56,8 +56,13 @@ fun assertThat(buildResult: BuildResult) = AssertBuildResult(buildResult)
 class AssertBuildResult(buildResult: BuildResult) : AbstractAssert<AssertBuildResult, BuildResult>(
     buildResult, AssertBuildResult::class.java) {
   fun executedTaskSuccessfully(name: String) {
+    executedTaskWithOutcome(name, TaskOutcome.SUCCESS)
+  }
+
+  fun executedTaskWithOutcome(name: String, outcome: TaskOutcome) {
     val task = actual.task(name) ?: throw AssertionError("didn't execute task $name")
     org.assertj.core.api.Assertions.assertThat(task.outcome).isEqualTo(TaskOutcome.SUCCESS)
+    org.assertj.core.api.Assertions.assertThat(task.outcome).isEqualTo(outcome)
   }
 
   fun hasOutputContaining(substring: String, times: Int = 1) {

android-junit5/src/main/groovy/de/mannodermaus/gradle/plugins/junit5/GroovyInterop.groovy

@@ -207,4 +207,52 @@ class GroovyInterop {
       report.sourceDirectories = project.files(paths)
     }
   }
+
+  /**
+   * Obtains the execution data of a Jacoco task.
+   *
+   * @because Gradle 5 changed the return type of this field to expose the ConfigurableFileCollection directly
+   * @param report Jacoco report task to operate on
+   * @return The execution data of the task
+   */
+  static ConfigurableFileCollection jacocoReportBase_getExecutionData(JacocoReportBase report) {
+    def val = report.executionData
+    if (val instanceof ConfigurableFileCollection) {
+      return val
+    } else {
+      return (ConfigurableFileCollection) val
+    }
+  }
+
+  /**
+   * Obtains the source directories of a Jacoco task.
+   *
+   * @because Gradle 5 changed the return type of this field to expose the ConfigurableFileCollection directly
+   * @param report Jacoco report task to operate on
+   * @return The source directories of the task
+   */
+  static ConfigurableFileCollection jacocoReportBase_getSourceDirectories(JacocoReportBase report) {
+    def val = report.sourceDirectories
+    if (val instanceof ConfigurableFileCollection) {
+      return val
+    } else {
+      return (ConfigurableFileCollection) val
+    }
+  }
+
+  /**
+   * Obtains the class directories of a Jacoco task.
+   *
+   * @because Gradle 5 changed the return type of this field to expose the ConfigurableFileCollection directly
+   * @param report Jacoco report task to operate on
+   * @return The class directories of the task
+   */
+  static ConfigurableFileCollection jacocoReportBase_getClassDirectories(JacocoReportBase report) {
+    def val = report.classDirectories
+    if (val instanceof ConfigurableFileCollection) {
+      return val
+    } else {
+      return (ConfigurableFileCollection) val
+    }
+  }
 }

android-junit5/src/main/kotlin/de/mannodermaus/gradle/plugins/junit5/Interop.kt

@@ -46,6 +46,15 @@ fun JacocoReportBase.safeSourceDirectoriesSetFrom(project: Project, vararg paths
   GroovyInterop.jacocoReportBase_sourceDirectories_setFrom(this, project, paths)
 }
 
+val JacocoReportBase.safeGetExecutionData get() =
+  GroovyInterop.jacocoReportBase_getExecutionData(this)
+
+val JacocoReportBase.safeGetSourceDirectories get() =
+  GroovyInterop.jacocoReportBase_getSourceDirectories(this)
+
+val JacocoReportBase.safeGetClassDirectories get() =
+  GroovyInterop.jacocoReportBase_getClassDirectories(this)
+
 /* Types */
 
 class VariantTypeCompat {

android-junit5/src/main/kotlin/de/mannodermaus/gradle/plugins/junit5/tasks/Jacoco.kt

@@ -10,7 +10,6 @@ import de.mannodermaus.gradle.plugins.junit5.providers.DirectoryProvider
 import de.mannodermaus.gradle.plugins.junit5.providers.mainClassDirectories
 import de.mannodermaus.gradle.plugins.junit5.providers.mainSourceDirectories
 import org.gradle.api.Project
-import org.gradle.api.file.ConfigurableFileCollection
 import org.gradle.api.file.FileCollection
 import org.gradle.api.tasks.testing.Test
 import org.gradle.testing.jacoco.plugins.JacocoTaskExtension
@@ -39,26 +38,6 @@ open class AndroidJUnit5JacocoReport : JacocoReport() {
     }
   }
 
-  /*
-   * Gradle 5.0 changed the return type of these methods from FileCollection to ConfigurableFileCollection.
-   * By explicitly re-declaring them here with the old return type, the binary incompatibility to Gradle 4.x is bridged.
-   */
-
-  @Suppress("RedundantOverride", "USELESS_CAST")
-  override fun getExecutionData(): ConfigurableFileCollection? {
-    return super.getExecutionData() as? ConfigurableFileCollection
-  }
-
-  @Suppress("RedundantOverride", "USELESS_CAST")
-  override fun getClassDirectories(): ConfigurableFileCollection? {
-    return super.getClassDirectories() as? ConfigurableFileCollection
-  }
-
-  @Suppress("RedundantOverride", "USELESS_CAST")
-  override fun getSourceDirectories(): ConfigurableFileCollection? {
-    return super.getSourceDirectories() as? ConfigurableFileCollection
-  }
-
   /**
    * Configuration closure for an Android JUnit5 Jacoco Report task.
    */
@@ -109,9 +88,9 @@ open class AndroidJUnit5JacocoReport : JacocoReport() {
 
       project.logger.junit5Info(
           "Assembled Jacoco Code Coverage for JUnit 5 Task '${testTask.name}':")
-      project.logger.junit5Info("|__ Execution Data: ${reportTask.executionData?.asPath}")
-      project.logger.junit5Info("|__ Source Dirs: ${reportTask.sourceDirectories?.asPath}")
-      project.logger.junit5Info("|__ Class Dirs: ${reportTask.classDirectories?.asPath}")
+      project.logger.junit5Info("|__ Execution Data: ${reportTask.safeGetExecutionData?.asPath}")
+      project.logger.junit5Info("|__ Source Dirs: ${reportTask.safeGetSourceDirectories?.asPath}")
+      project.logger.junit5Info("|__ Class Dirs: ${reportTask.safeGetClassDirectories?.asPath}")
 
       // Hook into the main Jacoco task
       val defaultJacocoTask = project.tasks.maybeCreate(

buildSrc/src/main/kotlin/Libs.kt

@@ -70,6 +70,14 @@ object Libs {
 
     const val android_junit5: String = "de.mannodermaus.gradle.plugins:android-junit5:" +
             Versions.android_junit5
+    /**
+     * https://mvnrepository.com/artifact/org.jacoco/org.jacoco.agent */
+    const val org_jacoco_agent: String = "org.jacoco:org.jacoco.agent:" + Versions.org_jacoco_agent
+
+    /**
+     * https://mvnrepository.com/artifact/org.jacoco/org.jacoco.ant */
+    const val org_jacoco_ant: String = "org.jacoco:org.jacoco.ant:" + Versions.org_jacoco_ant
+
 
     const val android_instrumentation_test_runner: String =
             "de.mannodermaus.junit5:android-instrumentation-test-runner:" +

buildSrc/src/main/kotlin/Versions.kt

@@ -47,7 +47,10 @@ object Versions {
 
     const val org_jetbrains_kotlin: String = "1.3.11" 
 
-    const val org_jetbrains_spek: String = "1.2.1" 
+    const val org_jetbrains_spek: String = "1.2.1"
+
+    const val org_jacoco_agent: String = "0.8.2"
+    const val org_jacoco_ant: String = "0.8.2"
 
     const val junit_pioneer: String = "0.2.2" // available: "0.3.0"