Unresolved reference: testing

According to official google documentation we should add our test helpers for Architecture Components (LiveData) in a such way:

// Test helpers for LiveData
testImplementation "android.arch.core:core-testing:1.1.0"

And at least for me it just doesn't work. (see the question above)

How it should be actually:

// Test helpers for LiveData
androidTestImplementation "android.arch.core:core-testing:1.1.0"

Now everything works just fine!

I just faced the same issue, and it was because I imported a newer version of junit, 4.13-beta-3. After downgrade to version 4.12, everything was fine.

testImplementation "junit:junit:4.12"

I hope this can be helpful for others.