Detox is gray box end-to-end testing and automation library for mobile apps. It has a lot of great features:

• Cross Platform
• Runs on Devices
• Automatically Synchronized
• Test Runner Independent
• Debuggable

Setting Up Detox

Install applesimutils (Mac only)

applesimutils is a collection of utils for Apple simulators.

Install Jest Globally

Generating Applications

By default, when creating a mobile application, Nx will use Detox to create the e2e tests project.

Creating a Detox E2E project for an existing project

You can create a new Detox E2E project for an existing mobile project.

If the @nx/detox package is not installed, install the version that matches your @nx/workspace version.

Next, generate an E2E project based on an existing project.

Replace your-app-name with the app's name as defined in your tsconfig.base.json file or the name property of your package.json.

In addition, you need to follow instructions at Detox to do manual setup for Android files.

Using Detox

Testing Applications

• Run nx test-ios frontend-e2e to build the iOS app and execute e2e tests with Detox for iOS (Mac only)
• Run nx test-android frontend-e2e to build the Android app and execute e2e tests with Detox for Android

You can run below commands:

• nx build-ios frontend-e2e: build the iOS app (Mac only)
• nx build-android frontend-e2e: build the Android app

Testing against Prod Build

You can run your e2e test against a production build:

• nx test-ios frontend-e2e --prod: to build the iOS app and execute e2e tests with Detox for iOS with Release configuration (Mac only)
• nx test-android frontend-e2e --prod: to build the Android app and execute e2e tests with Detox for Android with release build type
• nx build-ios frontend-e2e --prod: build the iOS app using Release configuration (Mac only)
• nx build-android frontend-e2e --prod: build the Android app using release build type

Configuration

Using .detoxrc.json

If you need to fine tune your Detox setup, you can do so by modifying .detoxrc.json in the e2e project.

Change Testing Simulator/Emulator

For iOS, in terminal, run xcrun simctl list devices available to view a list of simulators on your Mac. To open your active simulator, run open -a simulator. In frontend-e2e/.detoxrc.json, you could change the simulator under devices.simulator.device.

For Android, in terminal, run emulator -list-avds to view a list of emulators installed. To open your emulator, run emulator -avd <your emulator name>. In frontend-e2e/.detoxrc.json, you could change the simulator under devices.emulator.device.

In addition, to override the device name specified in a configuration, you could use --device-name option: nx test-ios <app-name-e2e> --device-name "iPhone 11". The device-name property provides you the ability to test an application run on specific device.