How to include a Annotation Processor generated code to test classpath in Java/Kotlin

Question

I have an Android project in process of migration from Java to Kotlin. In this project, I have a pure Kotlin module where I'm implementing a API Client with the following build.gradle:

apply plugin: 'kotlin'
apply plugin: 'kotlin-kapt'

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${kotlin_version}"
    implementation "com.squareup.retrofit2:retrofit:${retrofit_version}"
    implementation "com.squareup.retrofit2:converter-gson:${retrofit_version}"
    implementation "com.google.code.gson:gson:${gson_version}"
    implementation "com.squareup.okhttp3:logging-interceptor:${okhttp_version}"

    implementation "io.reactivex.rxjava2:rxjava:${rx_java_version}"
    implementation "io.reactivex.rxjava2:rxkotlin:${rx_kotlin_version}"
    implementation "com.jakewharton.retrofit:retrofit2-rxjava2-adapter:${retrofit2_rxjava2_adapter_version}"

    compileOnly "javax.annotation:jsr250-api:${jsr250_version}"
    implementation "com.google.dagger:dagger:${dagger_version}"
    kapt "com.google.dagger:dagger-compiler:${dagger_version}"

    testImplementation "junit:junit:${junit_version}"
    testImplementation "org.mockito:mockito-core:${mockito_version}"
    testImplementation "org.hamcrest:hamcrest-junit:${hamcrest_version}"
    testImplementation "com.squareup.okhttp3:mockwebserver:${mockwebserver_version}"

    // Dependence injection
    kaptTest "com.google.dagger:dagger-compiler:${dagger_version}"
}

There is an Annotation Processor dependency for unit tests:

kaptTest "com.google.dagger:dagger-compiler:${dagger_version}"

I can see the generated sources on build/generated/source/kapt/test directory, but they are not visible to the test sources, that is, is not possible to import the generated DaggerUnitTestComponent to inject dependencies, for exemple. And I'm having trouble to get it done.

This kind of thing I had already done with success on a Android project, with the help of this StackOverflow answer and the following snippet added to build.gradle, but for a pure Kotlin/Java project, it is not applicable.

android.applicationVariants.all {
  def aptOutputDir = new File(buildDir, "generated/source/apt/${it.unitTestVariant.dirName}")
  it.unitTestVariant.addJavaSourceFoldersToModel(aptOutputDir)
}

Is valid to say that I'm using Android Studio 3.0.1 and Kotlin 1.2.10. The sources of Kotlin library module lies on src/main/java and src/test/java.

Just to be sure, do you mean that the declarations from the generated files are not visible to the test sources? I couldn't get it what you mean by 'not included on classpath' and why would you need literally that. — hotkey, Jan 12 '18 at 13:53
@hotkey exactly. Maybe I could not find the right words to express myself. I need generated DaggerUnitTestComponent class be visible on my test classes. I edited the question to better understanding. — hugonardo, Jan 12 '18 at 14:12
Take a look at an example project that I created when I tried to reproduce the issue: https://github.com/h0tk3y/kt-dagger-example (it's a slightly modified project from [kotlin-examples](https://github.com/JetBrains/kotlin-examples/)) Seems to work fine for me. I think it can help if you provide more details about your project or make a simple sample project that shows what goes wrong. — hotkey, Jan 12 '18 at 15:42

hotkey · Accepted Answer · 2018-01-12T16:19:43.047

2

You might want to take a look at an example of a Kotlin project that uses dagger: (here)

From what I see, the test sources that use the generated classes should compile just fine during a Gradle build, but the IDE might not pick them up correctly.

Try updating Kotlin to a newer version in the project (1.2.10 should handle this). If that does not help, try using the idea plugin as in the example above, configured for the test generated sources as follows:

apply plugin: 'idea'

idea {
    module {
        testSourceDirs += file('build/generated/source/kapt/test')
        generatedSourceDirs += file('build/generated/source/kapt/test')
    }
}

edited Jan 12 '18 at 16:19

answered Jan 12 '18 at 15:50

hotkey

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Hey, @hotkey. Your help was very useful. To complement your answer, I had to move the source code from Java to Kotlin source set: from `src/main/java` to `src/main/kotlin`, and from `src/test/java` to `src/test/kotlin`. With this and applying Idea plugin, I had the solution. Thanks! – hugonardo Jan 15 '18 at 20:55
@hugonardo Glad I could help. – hotkey Jan 15 '18 at 21:07

How to include a Annotation Processor generated code to test classpath in Java/Kotlin

1 Answers1