java.lang.IncompatibleClassChangeError when including espresso-contrib:2.0

Question

I have a subclass of android.support.v7.widget.RecyclerView. It works fine when I use the application and testing.

However, when I include espresso-contrib in my gra

Answer 1

Maybe you forgot to add testInstrumentationRunner android.support.test.runner.AndroidJUnitRunner" in a defaultConfig{}