Configuring res srcDirs for androidTest sourceSet

Question

I'd like to include resources to be compiled only for testing.

I have the following in my app module build.gradle file:

android {

    ...

    sourceSets {
        androidTest {
            java.srcDirs = ['src/androidTest/java']
            res.srcDirs = ['src/androidTest/res']
        }
    }
}

The java srcDirs path is correct, yet if I try to get a resource from the res directory in androidTest, the resource can't be found.

How can I have resources in the androidTest directory that are only included for tests?

Answer 1

Turns out you don't need to change anything from the default build.gradle file.

The trick is that the auto-generated R.java file is different for resources in androidTest.

If the import statement for R somewhere in your main source set looks like:

import com.mycompany.myappname.R;

the import statement for R in a test file should look like:

import com.mycompany.myappname.test.R;

Answer 2

If you have a build type where you've set the applicationIdSuffix, your src/androidTest/res resources are going to be at <applicationId><applicationIdSuffix>.test.R !!!!! VERY IMPORTANT!!!

i.e.

applicationId "com.example.my.app"

buildTypes {
    debug {
        applicationIdSuffix ".debug"
    }
}

have some resources in src/androidTest/res? They're NOT at com.example.my.app.test! If you're running the debug build, they're at com.example.my.app.debug.test.R !!!!