How to add more build types in app than library

Question

Just like the example here I am extending my build types to add staging:

android {
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
        debug {
            applicationIdSuffix '.debug'
        }
        staging {
            initWith release
            applicationIdSuffix '.staging'
        }
    }
}

But I also have a dependency:

implementation project(':mylibrary')

Compilation fails because it doesn't know what to pair staging to in :mylibrary:

* What went wrong:
Could not determine the dependencies of task ':app:compileStagingJavaWithJavac'.
> Could not resolve all task dependencies for configuration ':app:stagingCompileClasspath'.
   > Could not resolve project :mylibrary.
     Required by:
         project :app
      > Unable to find a matching configuration of project :mylibrary:
          - Configuration 'debugApiElements':
              - Required com.android.build.api.attributes.BuildTypeAttr 'staging' and found incompatible value 'debug'.
              - Required com.android.build.gradle.internal.dependency.AndroidTypeAttr 'Aar' and found compatible value 'Aar'.
              - Found com.android.build.gradle.internal.dependency.VariantAttr 'debug' but wasn't required.
              - Required org.gradle.api.attributes.Usage 'java-api' and found compatible value 'java-api'.
          - Configuration 'debugRuntimeElements':
              - Required com.android.build.api.attributes.BuildTypeAttr 'staging' and found incompatible value 'debug'.
              - Required com.android.build.gradle.internal.dependency.AndroidTypeAttr 'Aar' and found compatible value 'Aar'.
              - Found com.android.build.gradle.internal.dependency.VariantAttr 'debug' but wasn't required.
              - Required org.gradle.api.attributes.Usage 'java-api' and found incompatible value 'java-runtime'.
          - Configuration 'releaseApiElements':
              - Required com.android.build.api.attributes.BuildTypeAttr 'staging' and found incompatible value 'release'.
              - Required com.android.build.gradle.internal.dependency.AndroidTypeAttr 'Aar' and found compatible value 'Aar'.
              - Found com.android.build.gradle.internal.dependency.VariantAttr 'release' but wasn't required.
              - Required org.gradle.api.attributes.Usage 'java-api' and found compatible value 'java-api'.
          - Configuration 'releaseRuntimeElements':
              - Required com.android.build.api.attributes.BuildTypeAttr 'staging' and found incompatible value 'release'.
              - Required com.android.build.gradle.internal.dependency.AndroidTypeAttr 'Aar' and found compatible value 'Aar'.
              - Found com.android.build.gradle.internal.dependency.VariantAttr 'release' but wasn't required.
              - Required org.gradle.api.attributes.Usage 'java-api' and found incompatible value 'java-runtime'.

That's fair enough, but I cannot go through all of my libraries adding staging just to get a different application suffix.

I tried:

debugImplementation project(path: ':mylibrary', configuration: 'debug')
releaseImplementation project(path: ':mylibrary', configuration: 'release')
stagingImplementation project(path: ':mylibrary', configuration: 'release')

But it fails:

* What went wrong:
Could not determine the dependencies of task ':app:compileReleaseJavaWithJavac'.
> Could not resolve all task dependencies for configuration ':app:releaseCompileClasspath'.
   > Could not resolve project :mylibrary.
     Required by:
         project :app
      > Project :app declares a dependency from configuration 'releaseImplementation' to configuration 'release' which is not declared in the descriptor for project :mylibrary.

debugImplementation project(path: ':mylibrary', configuration: 'default')
releaseImplementation project(path: ':mylibrary', configuration: 'default')
stagingImplementation project(path: ':mylibrary', configuration: 'default')

This works but every build has release build of library. I don't want that, I need debug to have debug version of library.

I've seen this q, but it's pre "implementation" and publishNonDefault true had no effect, same error as above.

publishNonDefault is deprecated and has no effect anymore. All variants are now published.

Gradlew version 4.6

Answer 1

Been here, done that :P

You'll need to specify matchingFallback with the Android Gradle Plugin 3.0.0 for the plugin to know which fallback build type of library to use when being compiled with app code in case a certain build type defined in your app is not found in library.

buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
    debug {
        applicationIdSuffix '.debug'
    }
    staging {
        initWith release
        applicationIdSuffix '.staging'
        matchingFallbacks = ['release']
    }
}

More info here: Migrate to Android Plugin for Gradle 3.0.0.