Instant use cases in Unit Test for a custom Gradle plugin that depends on an Android plugin

I am developing a Gradle plugin. My plugin depends on Android Gradle plugin. My plugin adds a task for each android app. Each task name is generated from the variant name.

public class MyPlugin implements Plugin<Project> {
    @Override
    void apply(Project project) {
        project.android.applicationVariants.all {
            project.task(type: SendApkTask, dependsOn: it.assemble, "send${it.name.capitalize()}Apk")
        }
    }
}

      

        
        
        
      

    

I want to create a unit test for MyPlugin # apply (Project). The test should verify that the task has been added. There should only be release and debug options by default.

public class MyPluginTest {

    Project project

    @Before
    public void setup() {
        project = ProjectBuilder.builder().build()
    }

    @Test
    public void testMyPluginAddsTasks() {
        project.apply plugin: 'com.android.application'
        project.apply plugin: MyPlugin

        assertNotNull(project.tasks['sendReleaseApk'])
    }
}

      

        
        
        
      

    

I cannot convey this statement. After debugging, I found it was project.applicationVariants

empty. My closure adding tasks never starts. How do I get the Android Gradle plugin that mocks my test? Do I need to customize my entire mock directory file with ProjectBuilder

?