React Native Automation Testing Using Detox

Detox is a JS-based end-to-end automation testing framework developed by Wix. Detox tests your mobile app while it's running on a real device or simulator, interacting with it just like an actual end user.

Appium is a popular mobile test automation framework that is often regarded as industry standard. Appium is based on black box testing, which simulates how an actual end user would interact with the app. In theory, this sounds great, but Appium tests are extremely unreliable. They frequently produce inconsistent results on different devices and are prone to frequent integration failures, resulting in slower tests.

• Since Detox is based on “Grey Box” testing which means that the tester has some knowledge of the internal workings of the application and this allows the framework to monitor the app from within and synchronize with it. Not only Grey Box testing is more stable than Black Box testing, but it's also much faster.
• Detox does not rely on WebDriver and interacts directly with the native layers of the app
• It synchronizes with the app's activity i.e. it times its actions to run only when your app is idle, meaning it has determined that your app has finished work, such as React Native load, animations, network requests, etc.
• Relatively easy setup process and the tests are also quite simple, readable, and can even be shared between platforms.

To get started with Detox, we’ll have to install the Detox command-line tools and the applesimutils library using the following commands.

This will create an e2e folder containing a few config files.

Detox for iOS does not require any additional setup; just go to the.detoxrc.json file and replace its content with the following: Make sure you replace "AppName” with the name of the app you have created.

$ detox build -c ios

Change minSdkVersion to 18 and add kotlinVersion = "1.3.41" in the ext block.

Add the following configuration inside allprojects.repositories

Add the following two lines in android.defaultConfig block

Add the following lines in the dependencies section

Create a DetoxTest.java file at the following location: android/app/src/androidTest/java/com/reactnativedetox/DetoxTest.java and refer here for the contents of the file. Don’t forget to change the package name of the file to that of your own project.

android/app/src/main/res/xml

In the app's AndroidManifest.xml, add the following -

Step 5: Update .detoxrc.json

$ detox build -c android

Add a testID property to the component that you want to find, like this:

You can write test cases like this:

• Build on the specific platform you want to test using the above-mentioned build command.
• Run the tests

Note: Starting with Xcode 9, Detox runs the iOS simulator in headless mode. If you are running the tests and the simulator does open up, then use Spotlight to pull up the simulator and hit enter, and it will bring all the simulators, detox has opened to the front.

• No support for expo
• Web Views are not supported; hence testing auth flows like Google, and Facebook is impossible. However, you can mock the external API to give you a predetermined auth token.