Rewire Jacoco for Gradle 8/9 (#3052)

Also generate coverage for the Android subproject.

.github/workflows/ci.yml

@@ -70,20 +70,14 @@ jobs:
         MOCK_MAKER: ${{ matrix.entry.mock-maker }}
         MEMBER_ACCESSOR: ${{ matrix.entry.member-accessor }}
 
-    - name: 7. Upload coverage report
-      run: |
-        ./gradlew coverageReport -s --scan && cp build/reports/jacoco/mockitoCoverage/mockitoCoverage.xml jacoco.xml
-        curl https://keybase.io/codecovsecurity/pgp_keys.asc | gpg --no-default-keyring --keyring trustedkeys.gpg --import # One-time step
+    - name: 7. Generate coverage report
+      run: ./gradlew coverageReport --stacktrace --scan
 
-        curl -Os https://uploader.codecov.io/latest/linux/codecov
-        curl -Os https://uploader.codecov.io/latest/linux/codecov.SHA256SUM
-        curl -Os https://uploader.codecov.io/latest/linux/codecov.SHA256SUM.sig
-
-        gpgv codecov.SHA256SUM.sig codecov.SHA256SUM
-        shasum -a 256 -c codecov.SHA256SUM
-
-        chmod +x codecov
-        ./codecov
+    - name: 8. Upload coverage report
+      uses: codecov/codecov-action@v3
+      with:
+        files: build/reports/jacoco/mockitoCoverage/mockitoCoverage.xml
+        fail_ci_if_error: true
 
   #
   # Android build job
@@ -166,6 +160,13 @@ jobs:
           ${{ github.workspace }}/emulator.log
           ${{ github.workspace }}/emulator-startup.log
 
+    # :androidTest:connectedCheck (which depends on :androidTest:createDebugAndroidTestCoverageReport) already generated coverage report.
+    - name: 5. Upload coverage report
+      uses: codecov/codecov-action@v3
+      with:
+        files: subprojects/androidTest/build/reports/coverage/androidTest/debug/connected/report.xml
+        fail_ci_if_error: true
+
   #
   # Release job, only for pushes to the main development branch
   #

gradle/root/coverage.gradle

@@ -1,43 +1,56 @@
-task mockitoCoverage(type: JacocoReport) {
-
-    allprojects { currentProject ->
-        // These tests do not have a `test` task.
-        if (currentProject.name in ['android']) {
-            return
+allprojects { project ->
+    plugins.withId("java") {
+        project.apply plugin: "jacoco"
+        project.jacoco {
+            toolVersion = '0.8.8'
         }
-        plugins.withId("java") {
-            mockitoCoverage.sourceSets currentProject.sourceSets.main
+    }
+}
 
-            apply plugin: "jacoco"
+def mockitoCoverage = tasks.register("mockitoCoverage", JacocoReport) { mockitoCoverage ->
+    allprojects { Project currentProject ->
+        plugins.withId("jacoco") {
+            plugins.withId("java") {
+                // JacocoReport.sourceSets() appends both sourceDirectories and classDirectories.
+                mockitoCoverage.sourceSets currentProject.sourceSets.main
+                Test test = currentProject.tasks.test
+                mockitoCoverage.executionData(currentProject.files(test.jacoco.destinationFile).builtBy(test))
+            }
+            plugins.withId("com.android.base") {
+                // The :androidTest project only contains test infrastructure, so there's no need to grab sources/classes.
 
-            jacoco {
-                toolVersion = '0.8.8'
+                def androidTest = currentProject.tasks.connectedDebugAndroidTest
+                def instrumentationCoverage = currentProject
+                    .layout.buildDirectory.dir("outputs/code_coverage/debugAndroidTest/connected")
+                    .map { it.asFileTree.matching { include "*/coverage.ec" } }
+                mockitoCoverage.executionData(currentProject.files(instrumentationCoverage))
+                mockitoCoverage.mustRunAfter(androidTest)
 
-                if (currentProject != rootProject) {   //already automatically enhanced in mockito main project as "java" plugin was applied before
-                    applyTo test
-                }
-                test.jacoco.destinationFile = file("${currentProject.buildDir}/jacoco/test.exec")
+                def unitTest = currentProject.tasks.testDebugUnitTest
+                def coverageFiles = currentProject
+                    .layout.buildDirectory.dir("outputs/unit_test_code_coverage/debugUnitTest")
+                    .map { it.asFileTree.matching { include "testDebugUnitTest.exec" } }
+                mockitoCoverage.executionData(currentProject.files(coverageFiles).builtBy(unitTest))
             }
+        }
+    }
 
-            mockitoCoverage.executionData(files(test.jacoco.destinationFile).builtBy(test))
-
-            afterEvaluate {
-                classDirectories.setFrom(
-                    classDirectories.files.collect {
-                        fileTree(
-                            dir: it,
-                            exclude: ["**/internal/util/concurrent/**"]
-                        )
-                    }
+    gradle.taskGraph.whenReady { // Theoretically Gradle.projectsEvaluated, but not possible here.
+        // Run this after all projects' sourceSets have been added (which is delayed to when the jacoco plugin is applied).
+        classDirectories.setFrom(
+            classDirectories.files.collect {
+                fileTree(
+                    dir: it,
+                    exclude: ["**/internal/util/concurrent/**"]
                 )
             }
-        }
+        )
     }
 
     reports {
         xml.required = true
         html.required = true
-        html.outputLocation = file("${buildDir}/jacocoHtml")
+        html.outputLocation = rootProject.layout.buildDirectory.dir("jacocoHtml")
     }
 
     doLast {
@@ -46,4 +59,6 @@ task mockitoCoverage(type: JacocoReport) {
     }
 }
 
-task coverageReport(dependsOn: ["mockitoCoverage"]) {}
+tasks.register("coverageReport") {
+    dependsOn(mockitoCoverage)
+}

subprojects/android/src/test/README.md

@@ -0,0 +1 @@
+Tests are located in :androidTest subproject.

subprojects/androidTest/androidTest.gradle

@@ -18,10 +18,39 @@ android {
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 
+    buildTypes {
+        debug {
+            enableUnitTestCoverage true
+            enableAndroidTestCoverage true
+        }
+    }
+    afterEvaluate {
+        // Enable coverage of mockito classes which are not part of this module.
+        // Without these added classFileCollection dependencies the coverage data/report is empty.
+        tasks.createDebugAndroidTestCoverageReport { com.android.build.gradle.internal.coverage.JacocoReportTask task ->
+            // Clear the production code of this module: src/main/java, it has no mockito-user-visible code.
+            task.classFileCollection.setFrom()
+            rootProject.allprojects { Project currentProject ->
+                plugins.withId("java") {
+                    SourceSetContainer sourceSets = currentProject.sourceSets
+                    // Mimic org.gradle.testing.jacoco.tasks.JacocoReportBase.sourceSets().
+                    // Not possible to set task.javaSources because it's initialized with setDisallowChanges.
+                    //task.javaSources.add({ [ sourceSets.main.allJava.srcDirs ] })
+                    task.classFileCollection.from(
+                        sourceSets.main.output.asFileTree.matching {
+                            exclude("**/internal/util/concurrent/**")
+                        }
+                    )
+                }
+            }
+        }
+    }
+
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_11
         targetCompatibility JavaVersion.VERSION_11
     }
+
     kotlinOptions {
         jvmTarget = '11'
     }
@@ -38,6 +67,12 @@ apply from: "$rootDir/gradle/dependencies.gradle"
 dependencies {
     implementation libraries.kotlin.stdlib
 
+    // Add :android on the classpath so that AGP's jacoco setup thinks it's "production code to be tested".
+    // Essentially a way to say: tasks.createDebugAndroidTestCoverageReport.classFileCollection.from(project(":android"))
+    runtimeOnly project(":android")
+    // Exclude :android from JVM tests, because otherwise it clashes with mockito-core/project(":").
+    configurations.testImplementation { exclude group: 'org.mockito', module: 'android' }
+
     testImplementation project(":")
     testImplementation libraries.junit4
     testImplementation libraries.junitJupiterApi