android getting coverage on local unit tests

Question

I've been trying to get the code coverage for my local unit tests and haven't been successful.

Here's a reference on what I mean by local unit tests.

https://developer.android.com/training/testing/unit-testing/local-unit-tests.html

To run my unit tests, I use the following gradle command.

./gradlew clean testDebugUnitTest

This task will run the unit tests but when I view the jacoco file that gets generated (testDebugUnitTest.ec) in "build/jacoco" folder, it always shows an empty coverage.

I've enabled the coverage in my build.gradle file as follows.

android {
    buildTypes {
        debug {
            testCoverageEnabled true
        }
    }
}

but that doesn't seem to help. Is there something that I am missing?

Note that if I run the local unit tests through Android Studio, everything works fine. I clicked on my "tests" module and click on "Run tests with coverage".

Answer 1

So, I found out the answer to my own question. Oddly enough, it looks like running "testDebugUnitTest" with the "testCoverageEnabled" flag set is the correct way to do it.

However, since apparently gradle's jacoco version is different than the jacoco version that is running in Android Studio and my CI system (Jenkins), it wasn't able to be viewed due to some backwards compatibility issue in jacoco.

To fix the issue, I set my jacoco version in gradle to the same one in my Android Studio (Intellij) and Jenkins.

jacoco {
    toolVersion = '0.7.0.201403182114'
}

I put the code above in my build.gradle file.