Test running failed: Unable to find instrumentation info for: ComponentInfo{} — error trying to test in IntelliJ with Gradle

Question

Everytime I try to run my tests the console says this:

Running tests
Test running startedTest running failed: Unable to find instrumentation info for:
ComponentI         


        

Answer 1

This is what I noticed in my project, in my app(main) module build.gradle I had the following buildType configuration

buildTypes {
        debug {
            multiDexEnabled true
        }

        mock {
            initWith(buildTypes.debug)
        }
    }
testBuildType "mock"

When I used AndroidJUnitRunner as the test runner(both from Android Studio) and as testInstrumentationRunner in build.gradle, tests ran without hitch.

In a submodule that had multiDexEnabled true as defaultConfig

defaultConfig {
    multiDexEnabled true
    ....
}

I ran into the problem of

Test running startedTest running failed: Unable to find instrumentation info for:{mypackage.x.y/android.support.test.runner.AndroidJUnitRunner"}

when I specified AndroidJUnitRunner in IDE and the submodule build.gradle. And this was fixed by specifying MultiDexTestRunner as the test runner in IDE/build.gradle.

To summarize, Use MultiDexTestRunner to run tests when multiDexEnabled true is specified in build.gradle, else use AndroidJUnitRunner as the test runner.