React Native

​

Produce a testable build

cd android && ./gradlew assembleRelease
# APK in android/app/build/outputs/apk/release/

xcodebuild \
  -workspace ios/MyApp.xcworkspace \
  -scheme MyApp \
  -sdk iphonesimulator \
  -configuration Debug \
  -derivedDataPath build \
  build-for-testing
# .app in build/Build/Products/Debug-iphonesimulator/

​

Upload and run

npm install --save-dev momentic-mobile

npx momentic-mobile assets upload ./android/app/build/outputs/apk/release/app-release.apk \
  --channel dev --tag 1.0.0

fileType: momentic/mobile-test/v2
id: rn-smoke
platform: android
labels: [smoke]
defaultChannel: dev
defaultTag: "1.0.0"
steps:
  - openApp: com.example.myapp
  - assert: The home screen is visible

npx momentic-mobile run smoke.test.yaml

​

React Native pitfalls

• Hermes and release-mode JS. The tested build is the compiled native app. JS-only changes (a moved button, a renamed screen) require a rebuild for the installed binary to reflect them.
• Metro is optional. A release APK embeds the JS bundle, so it needs no Metro server. A dev build that looks for Metro will hang at the loading screen if Metro is not running; test release/preview builds unless you specifically want dev-server coverage.
• testID becomes an accessibility identifier. React Native testID props surface to the native layer, so tap: the element with testID login works. But prefer describing what the user sees; targets survive refactors that change IDs.
• Third-party native modules (maps, cameras, Bluetooth) behave as they do on any emulator. Simulated camera/microphone input is available through setCamera/setMicrophone where supported; some hardware-backed features have no emulator equivalent.
• WebView content on Android needs WebView.setWebContentsDebuggingEnabled(true).
• Deep links open via an appium step (mobile: deepLink).

​

In CI

name: Mobile tests
on: [pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Set up Android toolchain
        uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: "17"

      - name: Build APK
        run: cd android && ./gradlew assembleRelease

      - name: Upload APK to Momentic
        run: |
          npm install
          npx momentic-mobile assets upload ./android/app/build/outputs/apk/release/app-release.apk \
            --channel dev --tag ${{ github.sha }}
        env:
          MOMENTIC_API_KEY: ${{ secrets.MOMENTIC_API_KEY }}

      - name: Run mobile tests
        run: |
          npx momentic-mobile run --labels smoke \
            --channel dev --tag ${{ github.sha }} -y
        env:
          MOMENTIC_API_KEY: ${{ secrets.MOMENTIC_API_KEY }}

​

Related

• Android app setup
• iOS app setup
• Expo guide for the Expo-managed workflow
• Emulators and simulators