How to import JUnit 5 source to Eclipse?

Question

I found some issues regarding taking JUnit5 (https://github.com/junit-team/junit5) inside my Eclipse IDE.

PS: I am using JDK 11 with correctly configured environment files in Windows 10. The same was done inside Eclipse.

I've done the steps:

• Fork to my github and clone it to my local machine.

• Using git bash entered project folder and ./gradlew clean build. Until this part everything went OK and completed sucessfully.

• Open Eclipse and imported as Gradle project.

• After syncing Eclipse workspace, I've got the errors:

Description Resource Path Location Type ArbitraryNamingKotlinTestCase cannot be resolved to a type AtypicalJvmMethodNameTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 34 Java Problem InstancePerClassKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 38 Java Problem InstancePerClassKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 43 Java Problem InstancePerClassKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 44 Java Problem InstancePerClassKotlinTestCase cannot be resolved to a type TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 37 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 55 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 60 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 64 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 67 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 70 Java Problem InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 74 Java Problem InstancePerMethodKotlinTestCase cannot be resolved to a type TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 54 Java Problem InstancePerMethodKotlinTestCase cannot be resolved to a type TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 65 Java Problem InstancePerMethodKotlinTestCase cannot be resolved to a type TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 66 Java Problem METHOD_NAME cannot be resolved to a variable AtypicalJvmMethodNameTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 39 Java Problem METHOD_NAME cannot be resolved to a variable AtypicalJvmMethodNameTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 40 Java Problem The import org.junit.jupiter.engine.kotlin.ArbitraryNamingKotlinTestCase cannot be resolved AtypicalJvmMethodNameTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 16 Java Problem The import org.junit.jupiter.engine.kotlin.ArbitraryNamingKotlinTestCase cannot be resolved AtypicalJvmMethodNameTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 19 Java Problem The import org.junit.jupiter.engine.kotlin.InstancePerClassKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 21 Java Problem The import org.junit.jupiter.engine.kotlin.InstancePerMethodKotlinTestCase cannot be resolved TestInstanceLifecycleKotlinTests.java /junit-jupiter-engine/src/test/java/org/junit/jupiter/engine line 22 Java Problem

It looks like It is not recognizing some Kotlin class files built-in the project. Any ideas on how to resolve this?

Answer 1

Eclipse IDE does not support compilation of Kotlin source code by default.

To get this working in Eclipse you will need to install the Kotlin Plugin for Eclipse and then right-click on the junit-jupiter-engine project and select "Configure Kotlin / Add Kotlin Nature".

Please note, however, that Kotlin Plugin for Eclipse has been known not to work consistently in Eclipse. Thus, you may simply want to ignore those compiler errors (which is embarrassingly what I actually do) or switch to IntelliJ IDEA.