OutputDirectoryProvider not available; probably due to unaligned versions of the junit-platform-engine and junit-platform-launcher jars on the classpath/module path.

[swaechter]

When switching from JUnit 5.11.4 to 5.12.0, all my tests fail at runtime:

Output:

PS SNIPPED_PATH\junittest> .\gradlew.bat build
> Task :test FAILED

[Incubating] Problems report is available at: file:///SNIPPED_PATH/junittest/build/reports/problems/problems-report.html

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':test'.
> There were failing tests. See the report at: file:///SNIPPED_PATH/junittest/build/reports/tests/test/index.html

* Try:
> Run with --scan to get full insights.

Deprecated Gradle features were used in this build, making it incompatible with Gradle 9.0.

You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.

For more on this, please refer to https://docs.gradle.org/8.13/userguide/command_line_interface.html#sec:command_line_warnings in the Gradle documentation.

BUILD FAILED in 2s
3 actionable tasks: 3 executed
PS SNIPPED_PATH\junittest>

Stacktrace:

org.gradle.api.internal.tasks.testing.TestSuiteExecutionException: Could not complete execution for Gradle Test Executor 1.
	at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:65)
	at java.base@21.0.4/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at java.base@21.0.4/java.lang.reflect.Method.invoke(Method.java:580)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
	at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
	at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
	at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:92)
	at jdk.proxy1/jdk.proxy1.$Proxy4.stop(Unknown Source)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker$3.run(TestWorker.java:200)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker.executeAndMaintainThreadName(TestWorker.java:132)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:103)
	at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:63)
	at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:56)
	at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:121)
	at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:71)
	at app//worker.org.gradle.process.internal.worker.GradleWorkerMain.run(GradleWorkerMain.java:69)
	at app//worker.org.gradle.process.internal.worker.GradleWorkerMain.main(GradleWorkerMain.java:74)
Caused by: org.junit.platform.commons.JUnitException: TestEngine with ID 'junit-jupiter' failed to discover tests
	at app//org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverEngineRoot(EngineDiscoveryOrchestrator.java:160)
	at app//org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverSafely(EngineDiscoveryOrchestrator.java:134)
	at app//org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discover(EngineDiscoveryOrchestrator.java:108)
	at app//org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discover(EngineDiscoveryOrchestrator.java:80)
	at app//org.junit.platform.launcher.core.DefaultLauncher.discover(DefaultLauncher.java:110)
	at app//org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86)
	at app//org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:124)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:99)
	at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:94)
	at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:63)
	... 16 more
Caused by: org.junit.platform.commons.JUnitException: OutputDirectoryProvider not available; probably due to unaligned versions of the junit-platform-engine and junit-platform-launcher jars on the classpath/module path.
	at app//org.junit.platform.engine.EngineDiscoveryRequest.getOutputDirectoryProvider(EngineDiscoveryRequest.java:94)
	at app//org.junit.jupiter.engine.JupiterTestEngine.discover(JupiterTestEngine.java:67)
	at app//org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverEngineRoot(EngineDiscoveryOrchestrator.java:152)
	... 26 more

Gradle wrapper version:

PS SNIPPED_PATH\junittest> .\gradlew.bat --version

------------------------------------------------------------
Gradle 8.13
------------------------------------------------------------

Build time:    2025-02-25 09:22:14 UTC
Revision:      073314332697ba45c16c0a0ce1891fa6794179ff

Kotlin:        2.0.21
Groovy:        3.0.22
Ant:           Apache Ant(TM) version 1.10.15 compiled on August 25 2024
Launcher JVM:  21.0.4 (Eclipse Adoptium 21.0.4+7-LTS)
Daemon JVM:    C:\Program Files\Eclipse Adoptium\jdk-21.0.4.7-hotspot (no JDK specified, using current Java home)
OS:            Windows 11 10.0 amd64

How to reproduce the problem (Reproducer: https://github.com/swaechter/junittest):

1.) Create a new Gradle project and update the Gradle wrapper to 8.13

2.) Create a new test case:

package com.swaechter;

import org.junit.jupiter.api.Test;

public class ExampleTest {

    @Test
    public void testHello() {
        System.out.println("Hello World");
    }
}

3.) Update the build.gradle.kts file:

plugins {
    id("java")
}

group = "ch.swaechter"
version = "1.0-SNAPSHOT"

repositories {
    mavenCentral()
}

dependencies {
    // Switch to JUnit version 5.12.0 to reproduce the error
    testImplementation(platform("org.junit:junit-bom:5.11.4"))
    //testImplementation(platform("org.junit:junit-bom:5.12.0"))
    testImplementation("org.junit.jupiter:junit-jupiter")
}

tasks.test {
    useJUnitPlatform()
}

4.) Toggle between JUnit version 5.11.4 and 5.12.0 and run the build/test command to reproduce the error.

Remarks:

• The problem also happens with older versions of the Gradle wrapper
• The problem also happens when using Java 23
• The problem happens from the command line and also from IntelliJ IDEA

[marcphilipp]

The root cause is that Gradle uses an old version of junit-platform-launcher if there is no explicit dependency on it on the test runtime classpath.

Please add a testRuntimeOnly("org.junit.platform:junit-platform-launcher") dependency. We've updated the User Guide a few days ago to reflect that.

[sbrannen]

Closing this as a:

• duplicate of 'TestEngine with ID 'junit-jupiter' failed to discover tests' on bump from 5.11.4 to 5.12.0 #4335

Specifying a testRuntimeOnly dependency on junit-platform-launcher should resolve the issue.

• See also Overhaul Gradle section regarding dependency alignment #4358

In the future, please search the issue tracker for related issues before creating a new issue.

Thanks

[sbrannen]

Oops... looks like @marcphilipp and I were typing at the same time. 😉

[swaechter]

Dear Marc and Sam. Thanks a lot for your fast reply and the explanation (Also in the linked issue regarding the new API). I was reading the changelog + using a time fixed Google search, but nothing showed up. But as you said, the issue search would have provided several of these issues. Sorry, my bad - have a nice weekend :)

[marcphilipp]

Sorry, my bad - have a nice weekend :)

No worries! You, too!