"Class not found" when running JUnit tests from IntelliJ IDEA (Android)

Question

I have a problem when trying to run some Android JUnit tests inside IntelliJ Idea.

My project is an Android Library project using Gradle. When I run my tests, IntelliJ complains with the following error:

Class not found: "com.domain.app.ClassTest"

But ClassTest is present inside the test package.

Here's my build.gradle:

apply plugin: 'android-library'

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:0.10.+'
    }
}

dependencies {
    repositories {
        mavenCentral()
        maven {
            url 'https://oss.sonatype.org/content/repositories/snapshots/'
        }
    }

    compile 'com.android.support:support-v4:19.1.+'

    compile('junit:junit:4.11') {
        exclude module: 'hamcrest-core'
    }
}

android {
    compileSdkVersion 18
    buildToolsVersion "19.0.3"

    defaultConfig {
        versionName "1.0"
        versionCode 1

        targetSdkVersion 18
    }

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src/main/java']
            res.srcDirs = ['res']
        }

        androidTest {
            java.srcDirs = ['src/test/java']
        }
    }

    lintOptions {
        abortOnError false
    }
}

My project structure:

src
|_ main
   |_ java
     |_ com.domain.app
|_ test
   |_ java
      |_ com.domain.app

I'm using IntelliJ IDEA 13.1.1.

Thanks.

Answer 1

Go to Project Structure -> Modules -> your_module -> Paths.

The value for 'Output path' should be filled in, but 'Test output path' will not be. Copy the text that's in 'Output path', paste into 'Test output path', but change the final 'build/intermediates/classes/debug' to 'build/test-classes'. This is because the gradle android test plugin currently dumps all compiled test output (for all variants) into the same directory. This means that currently variants are not fully supported.

Source.