“Empty test suite.” in pure kotlin module. (Spock/Android)

Empty Test Suite in Pure Kotlin Modules (Spock/Android)

Understanding the Issue

An “Empty test suite” error typically occurs when a testing framework like Spock, or JUnit in the context of Android development, fails to discover any tests in your Kotlin module. This can lead to frustrating situations where your tests appear to be missing, even though they are present within your project.

Causes

• Incorrect Test Configuration: Missing or misconfigured dependencies for your chosen testing framework (Spock, JUnit) or test runner (e.g., Android JUnit).
• Invalid Test Naming Conventions: Testing frameworks often rely on specific naming conventions to identify test classes and methods. Using non-standard names might lead to tests being overlooked.
• Module Structure: Incorrect or ambiguous module structure can sometimes hinder test discovery. Ensure your test code is located in an appropriate test source set and properly configured within your build.gradle files.
• Code Errors: Bugs within your test code (e.g., missing imports, invalid annotations) might prevent tests from executing correctly.

Troubleshooting Steps

1. Verify Dependencies and Configuration

• **Spock:**

  dependencies {
      testImplementation("org.spockframework:spock-core:2.0-groovy-3.0")
    }
    

• **Android JUnit:**

  dependencies {
      testImplementation("junit:junit:4.13.2")
      androidTestImplementation("androidx.test.ext:junit:1.1.5")
    }
    

2. Examine Test Naming Conventions

Ensure your test classes and methods follow the established naming conventions. For example:

• Spock: Test classes typically end with “Spec” (e.g., `MyClassSpec`), and test methods start with `’test’` or `’when’`.
• Android JUnit: Test classes usually end with “Test” (e.g., `MyClassTest`), and test methods often use the `@Test` annotation.

3. Check Module Structure

• In your `build.gradle` file, ensure your test code is placed within the appropriate test source set:

sourceSets {
    main.java.srcDirs 'src/main/java'
    test.java.srcDirs 'src/test/java'
    androidTest.java.srcDirs 'src/androidTest/java'
  }
  

4. Inspect Test Code for Errors

• Check for missing imports.
• Verify annotations are used correctly.
• Ensure test methods are accessible (not private).

Example: Spock

import spock.lang.Specification

class MyClassSpec extends Specification {
    def "should do something"() {
        expect:
        // Assertions and logic here
    }
}

Example: Android JUnit

import org.junit.Test

class MyClassTest {
    @Test
    fun `should do something`() {
        // Assertions and logic here
    }
}

Conclusion

By carefully examining your test configuration, naming conventions, module structure, and code for errors, you can resolve the “Empty test suite” issue and ensure your tests are properly discovered and executed. Remember, a robust test suite is crucial for maintaining the quality and stability of your Kotlin applications.