Using local cache for tests (#338)

Author: gmazzo

plugin/build.gradle.kts

@@ -104,7 +104,7 @@ mavenPublishing {
 }
 
 tasks.test {
-    environment("TEMP_DIR" to temporaryDir)
+    environment("TEMP_DIR", temporaryDir.toRelativeString(projectDir))
     useJUnitPlatform()
     javaLauncher = javaToolchains.launcherFor { languageVersion = JavaLanguageVersion.of(17) } // required by AGP
     finalizedBy(tasks.jacocoTestReport)

plugin/src/test/kotlin/com/github/gmazzo/buildconfig/BuildConfigPluginBaseTest.kt

@@ -16,7 +16,11 @@ import org.junit.jupiter.params.provider.MethodSource
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 abstract class BuildConfigPluginBaseTest(private val isKMP: Boolean = false) {
 
-    private val baseDir = File(System.getenv("TEMP_DIR"), javaClass.simpleName)
+    private val baseDir = File(
+        System.getenv("TEMP_DIR"),
+        javaClass.simpleName
+    ).absoluteFile
+
     protected val gradleMin = BuildConfigPlugin.MIN_GRADLE_VERSION
     protected val gradleLatest: String = GradleVersion.current().baseVersion.version
     protected val kotlinMin = "1.9.+"
@@ -58,7 +62,7 @@ abstract class BuildConfigPluginBaseTest(private val isKMP: Boolean = false) {
                 .withProjectDir(projectDir)
                 .withTestKitDir(projectDir.resolve(".testkit"))
                 .withGradleVersion(gradleVersion)
-                .withArguments("build", "-s")
+                .withArguments("build", "-s", "--build-cache")
                 .build()
         }
 
@@ -72,6 +76,10 @@ abstract class BuildConfigPluginBaseTest(private val isKMP: Boolean = false) {
         if (androidVersion != null) synchronized(BuildConfigPluginBaseTest, block) else block()
 
     private fun Args.writeBuildGradle() {
+        val userBuildCacheDir = File(System.getProperty("user.home"))
+            .resolve(".gradle/caches/build-cache-1")
+            .takeIf { it.isDirectory }
+
         projectDir.resolve("settings.gradle.kts").writeText(
             """
             pluginManagement {
@@ -85,6 +93,8 @@ abstract class BuildConfigPluginBaseTest(private val isKMP: Boolean = false) {
                 id("jacoco-testkit-coverage")
             }
 
+            ${ if (userBuildCacheDir != null) "buildCache.local.directory = file(\"$userBuildCacheDir\")" else "" }
+
             rootProject.name = "$PROJECT_NAME"
             """.trimIndent()
         )
@@ -193,7 +203,7 @@ abstract class BuildConfigPluginBaseTest(private val isKMP: Boolean = false) {
         val withPackage: Boolean = true,
     ) {
 
-        val projectDir = baseDir
+        val projectDir: File = baseDir
             .resolve("gradle-$gradleVersion")
             .resolve("kotlin-${kotlinVersion ?: "none"}")
             .resolve("android-${androidVersion ?: "none"}")

plugin/src/test/kotlin/com/github/gmazzo/buildconfig/BuildConfigTaskCacheabilityTest.kt

@@ -15,7 +15,10 @@ import org.junit.jupiter.api.parallel.ExecutionMode
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class BuildConfigTaskCacheabilityTest {
 
-    private val projectDir = File(System.getenv("TEMP_DIR"), BuildConfigTaskCacheabilityTest::class.simpleName!!)
+    private val projectDir = File(
+        System.getenv("TEMP_DIR"),
+        BuildConfigTaskCacheabilityTest::class.simpleName!!
+    ).absoluteFile
 
     private val buildScript = File(projectDir, "build.gradle.kts")