使用Robolectric进行测试时，Android WorkManager出错

Question

I'm using Android work manager with a custom initialization. to do that i disable auto-initialization in the manifest like this

        <provider
        tools:replace="android:authorities"
        android:name="androidx.work.impl.WorkManagerInitializer"
        android:authorities="${applicationId}.work_manager_init"
        android:enabled="false"
        android:exported="false" />

And in application code I use this code

private fun initWorkManager() {
    WorkManager.initialize(this, Configuration.Builder().run {
        setWorkerFactory(appComponent.daggerWorkerFactory())
        build()
    })
}

And it works fine when I run my application. But when I'm testing with roboletric any class that needs the context by RuntimeEnvironment.application throws this exception

java.lang.IllegalStateException: WorkManager is already initialized.  
Did you try to initialize it manually without disabling 
WorkManagerInitializer? See WorkManager#initialize(Context, 
Configuration) or the class levelJavadoc for more information.

The initWorkManager() get calls and throw this beacuse it doesn't know auto-init is already disabled in the manifest and somehow my test cannot read the values from the manifest file.

Any help or suggestion will be appritiated.

Answer 1

I solved a similar issue with the help of the Androidx Work Manager testing utils. For reference see the docs here: Android work manager testing docs

Basically what you need to do is add a dependency to include the work manger test utils:

testImplementation 'androidx.work:work-testing:2.0.1'

Then you will be able to call code in your test setup similar to this:

final Configuration config = new Configuration.Builder()
    .setMinimumLoggingLevel(Log.DEBUG)
    .setExecutor(new SynchronousExecutor())
    .build();
WorkManagerTestInitHelper.initializeTestWorkManager(
    context, config);

Whereas the context could obtained in different ways, depending on your test infrastructure.

With this approach no other steps like excluding something from the manifest are necessary.