Create Jacoco tasks optionally, yielding to existing task (but logging a warning) (#159)

Author: Marcel Schnelle

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

@@ -2,11 +2,7 @@ package de.mannodermaus.gradle.plugins.junit5
 
 import com.android.build.gradle.api.BaseVariant
 import com.android.builder.model.Version.ANDROID_GRADLE_PLUGIN_VERSION
-import de.mannodermaus.gradle.plugins.junit5.internal.android
-import de.mannodermaus.gradle.plugins.junit5.internal.createJUnit5ConfigurationFor
-import de.mannodermaus.gradle.plugins.junit5.internal.requireGradle
-import de.mannodermaus.gradle.plugins.junit5.internal.requireVersion
-import de.mannodermaus.gradle.plugins.junit5.internal.testTaskOf
+import de.mannodermaus.gradle.plugins.junit5.internal.*
 import de.mannodermaus.gradle.plugins.junit5.providers.DirectoryProvider
 import de.mannodermaus.gradle.plugins.junit5.providers.JavaDirectoryProvider
 import de.mannodermaus.gradle.plugins.junit5.providers.KotlinDirectoryProvider
@@ -94,7 +90,10 @@ class AndroidJUnitPlatformPlugin : Plugin<Project> {
         // Create a Jacoco friend task
         val enabledVariants = jacocoOptions.onlyGenerateTasksForVariants
         if (enabledVariants.isEmpty() || enabledVariants.contains(variant.name)) {
-          AndroidJUnit5JacocoReport.create(this, variant, testTask, directoryProviders)
+          val jacocoTask = AndroidJUnit5JacocoReport.create(this, variant, testTask, directoryProviders)
+          if (jacocoTask == null) {
+            project.logger.junit5Warn("Jacoco task for variant '${variant.name}' already exists. Disabling customization for JUnit 5...")
+          }
         }
       }
     }

plugin/android-junit5/src/main/kotlin/de/mannodermaus/gradle/plugins/junit5/internal/Extensions.kt

@@ -141,6 +141,13 @@ fun Logger.junit5Info(text: String) {
   info("[android-junit5]: $text")
 }
 
+/**
+ * Log the provided warning message using the plugin's Log Tag.
+ */
+fun Logger.junit5Warn(text: String) {
+  warn("[android-junit5]: $text")
+}
+
 /**
  * Shorthand function to check for the existence of a plugin on a Project.
  */

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

@@ -11,6 +11,7 @@ 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.FileCollection
+import org.gradle.api.tasks.CacheableTask
 import org.gradle.api.tasks.testing.Test
 import org.gradle.testing.jacoco.plugins.JacocoTaskExtension
 import org.gradle.testing.jacoco.tasks.JacocoReport
@@ -24,16 +25,21 @@ private const val GROUP_REPORTING = "reporting"
  * Required to be "open" in order for Groovy's proxy magic to do its thing.
  */
 @Suppress("MemberVisibilityCanPrivate")
+@CacheableTask
 open class AndroidJUnit5JacocoReport : JacocoReport() {
 
   companion object {
     fun create(project: Project,
                variant: BaseVariant,
                testTask: Test,
-               directoryProviders: Collection<DirectoryProvider>): AndroidJUnit5JacocoReport {
+               directoryProviders: Collection<DirectoryProvider>): AndroidJUnit5JacocoReport? {
       val configAction = ConfigAction(project, variant, testTask, directoryProviders)
-      return project.tasks.create(configAction.name, configAction.type) {
-        configAction.execute(it)
+      return if (project.tasks.findByName(configAction.name) == null) {
+        project.tasks.create(configAction.name, configAction.type) {
+          configAction.execute(it)
+        }
+      } else {
+        null
       }
     }
   }

plugin/android-junit5/src/test/kotlin/de/mannodermaus/gradle/plugins/junit5/PluginSpec.kt

@@ -13,6 +13,7 @@ import org.gradle.api.ProjectConfigurationException
 import org.gradle.api.Task
 import org.gradle.api.internal.plugins.PluginApplicationException
 import org.gradle.api.tasks.testing.Test
+import org.gradle.testing.jacoco.tasks.JacocoReport
 import org.jetbrains.spek.api.Spek
 import org.jetbrains.spek.api.dsl.context
 import org.jetbrains.spek.api.dsl.describe
@@ -239,6 +240,18 @@ class PluginSpec : Spek({
           }
         }
 
+        on("having a Jacoco task already") {
+          val project = testProjectBuilder.build()
+          project.tasks.create("jacocoTestReportDebug", JacocoReport::class.java)
+          project.evaluate()
+
+          it("doesn't cause a conflict") {
+            assertThat(project.tasks.findByName("jacocoTestReport")).isNotNull()
+            assertThat(project.tasks.findByName("jacocoTestReportDebug")).isInstanceOf(JacocoReport::class.java)
+            assertThat(project.tasks.findByName("jacocoTestReportRelease")).isInstanceOf(AndroidJUnit5JacocoReport::class.java)
+          }
+        }
+
         on("using a custom build type") {
           val project = testProjectBuilder.build()