Enable JaCoCo test coverage for debug builds

.github/workflows/main.yml

@@ -74,18 +74,34 @@ jobs:
           setup-rust: true
       - name: Full Gradle Test
         run: ./gradlew assembleDebug assembleAndroidTest assembleUnitTest test
+  jacoco:
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@ec9f2d5744a09debf3a187a3f4f675c53b671911 # v2.13.0
+        with:
+          egress-policy: audit
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v3.5.2
+        with:
+          submodules: 'recursive'
+      - name: Set up Build
+        uses: ./.github/actions/setup-build
+        with:
+          setup-gradle: true
+          setup-protoc: true
+          setup-rust: true
       - name: Generate JaCoCo Report
-        run: ./gradlew jacocoTestReport
+        run: ./gradlew designcompose:jacocoDebugUnitTestReport
       - name: Upload JaCoCo Report
         uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: jacoco-report
-          path: build/reports/jacoco/jacocoTestReport/html
+          path: designcompose/build/reports/jacoco/jacocoDebugUnitTestReport/html
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
-          files: build/reports/jacoco/jacocoTestReport/jacocoTestReport.xml
+          files: designcompose/build/reports/jacoco/jacocoDebugUnitTestReport/jacocoDebugUnitTestReport.xml
           flags: kotlin
   build-maven-repo:
     runs-on: "ubuntu-latest"

build.gradle.kts

@@ -49,37 +49,3 @@ for (projectName in listOf("tutorial-app", "helloworld-app", "cluster-demo", "me
         project(projectName).plugins.apply("designcompose.conventions.roborazzi")
     }
 }
-
-subprojects { apply(plugin = "jacoco") }
-
-tasks.register<JacocoReport>("jacocoTestReport") {
-    dependsOn(subprojects.map { it.tasks.withType<Test>() })
-    dependsOn(subprojects.map { it.tasks.withType<JacocoReport>() })
-
-    val coreModules = listOf("annotation", "common", "designcompose")
-    val source =
-        files(
-            subprojects
-                .filter { it.name in coreModules }
-                .map {
-                    val sourceSets = it.extensions.findByType(SourceSetContainer::class.java)
-                    sourceSets?.findByName("main")?.allSource
-                }
-        )
-    sourceDirectories.setFrom(source)
-    classDirectories.setFrom(
-        files(
-            subprojects
-                .filter { it.name in coreModules }
-                .map {
-                    val sourceSets = it.extensions.findByType(SourceSetContainer::class.java)
-                    sourceSets?.findByName("main")?.output
-                }
-        )
-    )
-    executionData.setFrom(fileTree(project.rootDir) { include("**/build/jacoco/test.exec") })
-    reports {
-        xml.required.set(true)
-        html.required.set(true)
-    }
-}

designcompose/build.gradle.kts

@@ -60,6 +60,7 @@ android {
             initWith(buildTypes.getByName("release"))
             matchingFallbacks.add("release")
         }
+        debug { enableUnitTestCoverage = true }
     }
 
     packaging {
@@ -69,10 +70,61 @@ android {
             add("META-INF/LGPL2.1")
         }
     }
-    testOptions { unitTests { isIncludeAndroidResources = true } }
+    testOptions {
+        unitTests {
+            isIncludeAndroidResources = true
+            all { test ->
+                test.extensions.configure<JacocoTaskExtension> {
+                    // These classes are not supposed to be accessible
+                    excludes = listOf("jdk.internal.*")
+                    isIncludeNoLocationClasses =
+                        true // Include classes without location information
+                }
+            }
+        }
+    }
 }
 
-tasks.withType<Test> { jacoco { isEnabled = true } }
+tasks.register<JacocoReport>("jacocoDebugUnitTestReport") {
+    group = "verification"
+    dependsOn(tasks.named("testDebugUnitTest"))
+
+    // Point Jacoco to the source code. This correctly finds both Java and Kotlin files.
+    val mainSourceSet = android.sourceSets.getByName("main").java.srcDirs
+    sourceDirectories.setFrom(files(mainSourceSet))
+
+    val jacocoExcludes =
+        listOf(
+            "**/R.class",
+            "**/R$*.class",
+            "**/BuildConfig.*",
+            "**/Manifest*.*",
+            "**/*Test*.*",
+            // Add other classes or packages to exclude from coverage as needed
+        )
+
+    // Point Jacoco to the classes that were generated by the compilation
+    classDirectories.setFrom(
+        files(
+            fileTree(layout.buildDirectory.dir("intermediates/javac/debug")) {
+                exclude(jacocoExcludes)
+            },
+            fileTree(layout.buildDirectory.dir("tmp/kotlin-classes/debug")) {
+                exclude(jacocoExcludes)
+            },
+        )
+    )
+    // Collect execution data from .exec and .ec files generated during test execution
+    executionData.setFrom(
+        files(fileTree(layout.buildDirectory) { include(listOf("**/*.exec", "**/*.ec")) })
+    )
+    println(executionData.files.joinToString("\n"))
+
+    reports {
+        html.required.set(true)
+        xml.required.set(true)
+    }
+}
 
 // To simplify publishing of the entire SDK, make the DesignCompose publish tasks depend on the
 // Gradle Plugin's publish tasks