The following is a project that uses Kotlin and has unit and ui tests written in Kotlin

• Setup Steps
• Tools
• How to run the project locally
• Helpful resources

To setup Android for espresso tests, go to the app/build.gradle and add the following and then sync the gradle.

androidTestImplementation 'androidx.test:rules:1.1.1'
androidTestImplementation 'androidx.test.ext:truth:1.1.0'
androidTestImplementation 'androidx.test.ext:junit:1.1.0'

Update the AndroidManifest.xml.

<activity android:name=".SecondActivity"
    android:parentActivityName=".MainActivity"/>

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To run the unit tests locally.

./gradlew testdebugUnitTest

To run the ui tests locally, but first we need an emulator to be open.

./gradlew connectedCheck

The following link provides an intro on how you can use Kotlin with Android including the Java examples.

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A good guide for writing espresso tests in Kotlin.

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Another guide on how to write espresso tests in Kotlin

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Guide for how to use Fastlane to run tests.

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A helpful guide for how to use Intents in Kotlin, plus how to avoid using set setOnClickListener.

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