espresso-skill

name espresso-skill description Generates Espresso UI tests for Android apps in Kotlin or Java. Espresso runs inside the app process for fast, reliable UI testing. Supports local and TestMu AI cloud real devices. Use when user mentions "Espresso", "onView", "ViewMatchers", "Android UI test", or "instrumentation test". Triggers on: "Espresso", "onView", "ViewMatchers", "Android UI test", "instrumentation", "TestMu". languages ["Java","Kotlin"] category mobile-testing license MIT metadata {"author":"TestMu AI","version":"1.0"} Espresso Automation Skill You are a senior Android QA engineer specializing in Espresso UI testing. Step 1 — Execution Target ├─ Mentions "cloud", "TestMu", "LambdaTest", "device farm"? │ └─ TestMu AI cloud (upload APK + test APK) │ ├─ Mentions "emulator", "local", "connected device"? │ └─ Local: ./gradlew connectedAndroidTest │ └─ Default → Local emulator Core Patterns — Kotlin (Default) Basic Test @RunWith(AndroidJUnit4::class) class LoginTest { @get:Rule val activityRule = ActivityScenarioRule(LoginActivity:: class .java) @Test fun loginWithValidCredentials () { // Type email onView(withId(R.id.emailInput)) .perform(typeText( "user@test.com" ), closeSoftKeyboard()) // Type password onView(withId(R.id.passwordInput)) .perform(typeText( "password123" ), closeSoftKeyboard()) // Click login button onView(withId(R.id.loginButton)) .perform(click()) // Verify dashboard is displayed onView(withId(R.id.dashboardTitle)) .check(matches(isDisplayed())) .check(matches(withText( "Welcome" ))) } @Test fun loginWithInvalidCredentials_showsError () { onView(withId(R.id.emailInput)) .perform(typeText( "wrong@test.com" ), closeSoftKeyboard()) onView(withId(R.id.passwordInput)) .perform(typeText( "wrong" ), closeSoftKeyboard()) onView(withId(R.id.loginButton)) .perform(click()) onView(withId(R.id.errorText)) .check(matches(isDisplayed())) .check(matches(withText(containsString( "Invalid" )))) } } ViewMatchers (Finding Elements) // By ID (best) onView(withId(R.id.loginButton)) // By text onView(withText( "Login" )) // By content description (accessibility) onView(withContentDescription( "Submit form" )) // By hint text onView(withHint( "Enter your email" )) // Combined matchers onView(allOf(withId(R.id.button), withText( "Submit" ), isDisplayed())) // In RecyclerView onView(withId(R.id.recyclerView)) .perform(RecyclerViewActions.actionOnItemAtPosition<ViewHolder>( 0 , click())) // By parent onView(allOf(withText( "Delete" ), isDescendantOfA(withId(R.id.toolbar)))) ViewActions (Performing Actions) .perform(click()) // Tap .perform(longClick()) // Long press .perform(typeText( "hello" )) // Type text .perform(replaceText( "new text" )) // Replace text .perform(clearText()) // Clear field .perform(closeSoftKeyboard()) // Dismiss keyboard .perform(scrollTo()) // Scroll to element .perform(swipeUp()) // Swipe gesture .perform(swipeDown()) .perform(swipeLeft()) .perform(swipeRight()) .perform(pressBack()) // Back button ViewAssertions (Checking State) .check(matches(isDisplayed())) // Visible .check(matches(not(isDisplayed()))) // Not visible .check(matches(withText( "Expected" ))) // Text matches .check(matches(isEnabled())) // Enabled .check(matches(isChecked())) // Checkbox checked .check(matches(hasErrorText( "Required" ))) // Error text .check(doesNotExist()) // Not in hierarchy Idling Resources (Async Operations) // Register before test @Before fun setUp () { IdlingRegistry.getInstance().register(myIdlingResource) } // Unregister after test @After fun tearDown () { IdlingRegistry.getInstance().unregister(myIdlingResource) } // Custom IdlingResource for network calls class NetworkIdlingResource : IdlingResource { private var callback: IdlingResource.ResourceCallback? = null private var isIdle = true override fun getName () = "NetworkIdlingResource" override fun isIdleNow () = isIdle override fun registerIdleTransitionCallback (callback: ResourceCallback ) { this .callback = callback } fun setIdle (idle: Boolean ) { isIdle = idle if (idle) callback?.onTransitionToIdle() } } Anti-Patterns Bad Good Why Thread.sleep() IdlingResources Espresso auto-syncs UI thread XPath-like traversal withId(R.id.x) Direct ID is fastest Testing across activities Test single screen, mock data Isolation No closeSoftKeyboard() Always close after typeText() Keyboard blocks elements TestMu AI Cloud # 1. Build APK and test APK ./gradlew assembleDebug assembleDebugAndroidTest # 2. Upload both to LambdaTest curl -u " $LT_USERNAME : $LT_ACCESS_KEY " \ -X POST "https://manual-api.lambdatest.com/app/upload/realDevice" \ -F "appFile=@app/build/outputs/apk/debug/app-debug.apk" \ -F "type=android" curl -u " $LT_USERNAME : $LT_ACCESS_KEY " \ -X POST "https://manual-api.lambdatest.com/app/upload/realDevice" \ -F "appFile=@app/build/outputs/apk/androidTest/debug/app-debug-androidTest.apk" \ -F "type=android" # 3. Execute on real devices via API curl -u " $LT_USERNAME : $LT_ACCESS_KEY " \ -X POST "https://mobile-api.lambdatest.com/framework/v1/espresso/build" \ -H "Content-Type: application/json" \ -d '{ "app": "lt://APP123", "testSuite": "lt://TEST456", "device": ["Pixel 8-14", "Galaxy S24-14"], "build": "Espresso Cloud Build", "video": true, "deviceLog": true }' build.gradle Setup android { defaultConfig { testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner" } } dependencies { androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1' androidTestImplementation 'androidx.test.espresso:espresso-contrib:3.5.1' androidTestImplementation 'androidx.test.espresso:espresso-intents:3.5.1' androidTestImplementation 'androidx.test:runner:1.5.2' androidTestImplementation 'androidx.test:rules:1.5.0' androidTestImplementation 'androidx.test.ext:junit:1.1.5' } Quick Reference Task Command/Code Run all tests ./gradlew connectedAndroidTest Run specific class ./gradlew connectedAndroidTest -Pandroid.testInstrumentationRunnerArguments.class=com.example.LoginTest Run on specific device ./gradlew connectedAndroidTest -PtestDevice=emulator-5554 Intent verification Intents.init() → intended(hasComponent(...)) → Intents.release() RecyclerView scroll RecyclerViewActions.scrollToPosition<>(10) Screenshot Screenshot.capture(activityRule.activity) Reference Files File When to Read reference/cloud-integration.md LambdaTest Espresso, device farm, API reference/advanced-patterns.md Intents, RecyclerView, custom matchers Deep Patterns → reference/playbook.md § Section Lines 1 Project Setup Gradle deps, Orchestrator 2 Test Structure & Lifecycle Rules, permissions, annotations 3 Custom Matchers & ViewActions RecyclerView, wait, scroll 4 RecyclerView Testing Scroll, click child, swipe, assert 5 Idling Resources Counting, OkHttp, custom 6 Intent Testing Share, stub, camera 7 MockWebServer for API Tests Enqueue, error handling 8 CI/CD Integration GitHub Actions, emulator runner 9 Debugging Quick-Reference 10 common problems 10 Best Practices Checklist 13 items