NullPointer Exception when using Espresso

Question

I\'m trying to use Espresso. But I got this error and I have no if I\'m missing some codes.

any thoughts will be highly appreciated.

error log:

Answer 1

If you have a dependent library with unit test applied, the libary should have same instrument setup also as below.

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"