New error after update to gradle-tool to 3.1.0-beta3 or 3.2.0-alpha03

Question

Just a normal project with "prod" and "mock" flavors

in app/build.gradle:

 sourceSets {
        main.java.srcDirs += "blabla bla"
        test.java.srcDirs += "blabla bla"
        androidTest.java.srcDirs += "blabla bla"

        prodDebug.java.srcDirs += "blabla bla"
        mockDebug.java.srcDirs += "blabla bla"

        prod.java.srcDirs += "blabla bla"
        testProd.java.srcDirs += "blabla bla"
        androidTestProd.java.srcDirs += "blabla bla"

        mock.java.srcDirs += "blabla bla"
        testMock.java.srcDirs += "blabla bla"
        androidTestMock.java.srcDirs += "blabla bla"
    }

click "run" in Android Studio :

something goes wrong:

Error:org.gradle.api.GradleException: The SourceSet 'mockDebug' is not recognized by the Android Gradle Plugin. Perhaps you misspelled something?

However, I can do "./gradlew clean build" or "./gradlew assembleProd installProdDebug" etc.

But, if I do it in command-line, the app cannot be built completely, it can install the app on the target device, but the app will crash like "xxxx.dex" problem.

issue

Answer 1

Encountered the same problem after updating the Gradle Plugin from 3.0.1 to 3.1.0. Seems like Gradle now only finds the source set for the variant that is selected in Android Studio.

A workaround that fixes it for now is to remove the sourceSets {} block and add this instead:

def customSourceSets = [
    myFirstBuildVariant: 'src/myFirstBuildVariant',
    mySecondBuildVariant: 'src/mySecondBuildVariant',
]

android.applicationVariants.all { 
    if (customSourceSets.containsKey(name)) {
        sourceSets.find { it.name == name }.setRoot(customSourceSets.get(name))
    }
}