4 files changed, 68 insertions, 4 deletions
diff --git a/buildSrc/src/main/java/BaseProjectConfig.kt b/buildSrc/src/main/java/BaseProjectConfig.kt
index a829d4f7..e4dfa7e4 100644
--- a/buildSrc/src/main/java/BaseProjectConfig.kt
+++ b/buildSrc/src/main/java/BaseProjectConfig.kt
@@ -13,6 +13,7 @@ import org.gradle.api.tasks.wrapper.Wrapper
 import org.gradle.kotlin.dsl.maven
 import org.gradle.kotlin.dsl.repositories
 import org.gradle.kotlin.dsl.withType
+import org.gradle.language.nativeplatform.internal.BuildType
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 /**
@@ -50,9 +51,10 @@ internal fun Project.configureForAllProjects() {
       languageVersion = "1.5"
     }
   }
-  tasks.withType<Test> {
+  tasks.withType<Test>().configureEach {
     maxParallelForks = Runtime.getRuntime().availableProcessors() * 2
     testLogging { events(TestLogEvent.PASSED, TestLogEvent.SKIPPED, TestLogEvent.FAILED) }
+    outputs.upToDateWhen { false }
   }
 }
 
@@ -79,13 +81,19 @@ internal fun BaseAppModuleExtension.configureAndroidApplicationOptions(project:
     buildConfig = true
   }
 
+  flavorDimensions(FlavorDimensions.FREE)
+  productFlavors {
+    create(ProductFlavors.FREE) {}
+    create(ProductFlavors.NON_FREE) {}
+  }
+
   buildTypes {
-    named("release") {
+    named(BuildType.RELEASE.name) {
       isMinifyEnabled = !minifySwitch.isPresent
       setProguardFiles(listOf("proguard-android-optimize.txt", "proguard-rules.pro"))
       buildConfigField("boolean", "ENABLE_DEBUG_FEATURES", "${project.isSnapshot()}")
     }
-    named("debug") {
+    named(BuildType.DEBUG.name) {
       applicationIdSuffix = ".debug"
       versionNameSuffix = "-debug"
       isMinifyEnabled = false
@@ -121,5 +129,8 @@ internal fun TestedExtension.configureCommonAndroidOptions() {
     targetCompatibility = JavaVersion.VERSION_1_8
   }
 
-  testOptions.animationsDisabled = true
+  testOptions {
+    animationsDisabled = true
+    unitTests.isReturnDefaultValues = true
+  }
 }
diff --git a/buildSrc/src/main/java/PasswordStorePlugin.kt b/buildSrc/src/main/java/PasswordStorePlugin.kt
index 0705de82..df491e0d 100644
--- a/buildSrc/src/main/java/PasswordStorePlugin.kt
+++ b/buildSrc/src/main/java/PasswordStorePlugin.kt
@@ -43,6 +43,7 @@ class PasswordStorePlugin : Plugin<Project> {
         is LibraryPlugin -> {
           project.extensions.getByType<TestedExtension>().configureCommonAndroidOptions()
           project.configureExplicitApi()
+          project.configureSlimTests()
         }
         is AppPlugin -> {
           project
@@ -51,6 +52,7 @@ class PasswordStorePlugin : Plugin<Project> {
             .configureAndroidApplicationOptions(project)
           project.extensions.getByType<BaseAppModuleExtension>().configureBuildSigning(project)
           project.extensions.getByType<TestedExtension>().configureCommonAndroidOptions()
+          project.configureSlimTests()
         }
         is SigningPlugin -> {
           project.extensions.getByType<SigningExtension>().configureBuildSigning()
diff --git a/buildSrc/src/main/java/ProductFlavors.kt b/buildSrc/src/main/java/ProductFlavors.kt
new file mode 100644
index 00000000..5b722a37
--- /dev/null
+++ b/buildSrc/src/main/java/ProductFlavors.kt
@@ -0,0 +1,13 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+object FlavorDimensions {
+  const val FREE = "free"
+}
+
+object ProductFlavors {
+  const val FREE = "free"
+  const val NON_FREE = "nonFree"
+}
diff --git a/buildSrc/src/main/java/SlimTests.kt b/buildSrc/src/main/java/SlimTests.kt
new file mode 100644
index 00000000..65e9c618
--- /dev/null
+++ b/buildSrc/src/main/java/SlimTests.kt
@@ -0,0 +1,38 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+import com.android.build.api.extension.ApplicationAndroidComponentsExtension
+import com.android.build.api.extension.LibraryAndroidComponentsExtension
+import org.gradle.api.Project
+import org.gradle.kotlin.dsl.findByType
+import org.gradle.language.nativeplatform.internal.BuildType
+
+/**
+ * When the "slimTests" project property is provided, disable the unit test tasks on `release` build
+ * type and `nonFree` product flavor to avoid running the same tests repeatedly in different build
+ * variants.
+ *
+ * Examples: `./gradlew test -PslimTests` will run unit tests for `nonFreeDebug` and `debug` build
+ * variants in Android App and Library projects, and all tests in JVM projects.
+ */
+internal fun Project.configureSlimTests() {
+  if (providers.gradleProperty(SLIM_TESTS_PROPERTY).forUseAtConfigurationTime().isPresent) {
+    // disable unit test tasks on the release build type for Android Library projects
+    extensions.findByType<LibraryAndroidComponentsExtension>()?.run {
+      beforeUnitTests(selector().withBuildType(BuildType.RELEASE.name)) { it.enabled = false }
+    }
+
+    // disable unit test tasks on the release build type and free flavor for Android Application
+    // projects.
+    extensions.findByType<ApplicationAndroidComponentsExtension>()?.run {
+      beforeUnitTests(selector().withBuildType(BuildType.RELEASE.name)) { it.enabled = false }
+      beforeUnitTests(selector().withFlavor(FlavorDimensions.FREE to ProductFlavors.NON_FREE)) {
+        it.enabled = false
+      }
+    }
+  }
+}
+
+private const val SLIM_TESTS_PROPERTY = "slimTests"