'org.junit.platform.commons.JUnitException: TestEngine with ID 'junit-jupiter' failed to discover tests

I wan to implement a Junit 5 test into Gradle project. I tried this:

Gradle configuration:

plugins {
    id 'org.springframework.boot' version '2.5.5'
    id 'io.spring.dependency-management' version '1.0.11.RELEASE'
    id 'java'
}

group = 'test'
version = '0.0.1'
sourceCompatibility = '17'

repositories {
    mavenCentral()
}

ext {
    set('springCloudVersion', "2020.0.4")
}

dependencies {
    ...............
    testImplementation 'org.springframework.boot:spring-boot-starter-test'
    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.2'
    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.2'
}

dependencyManagement {
    imports {
        mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
    }
}

test {
    useJUnitPlatform()
}

Junit test:

import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.Timeout;

import java.util.concurrent.TimeUnit;

public class GeneratePdf {

    @DisplayName("Test MessageService.get()")
    @Test
    @Timeout(value = 60, unit = TimeUnit.SECONDS)
    public void generatePdfFileTes() throws InterruptedException
    {
        System.out.println("test!");
    }

}

When I run the code I get error:

Internal Error occurred.
org.junit.platform.commons.JUnitException: TestEngine with ID 'junit-jupiter' failed to discover tests
    at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverEngineRoot(EngineDiscoveryOrchestrator.java:160)
    at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverSafely(EngineDiscoveryOrchestrator.java:134)
    at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discover(EngineDiscoveryOrchestrator.java:108)
    at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discover(EngineDiscoveryOrchestrator.java:80)
    at org.junit.platform.launcher.core.DefaultLauncher.discover(DefaultLauncher.java:110)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86)
    at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86)
    at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:53)
    at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
    at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)
Caused by: org.junit.platform.commons.JUnitException: MethodSelector [className = 'org.merchant.poc.GeneratePdf', methodName = 'generatePdfFileTes', methodParameterTypes = ''] resolution failed
    at org.junit.platform.launcher.listeners.discovery.AbortOnFailureLauncherDiscoveryListener.selectorProcessed(AbortOnFailureLauncherDiscoveryListener.java:39)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolveCompletely(EngineDiscoveryRequestResolution.java:102)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.run(EngineDiscoveryRequestResolution.java:82)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver.resolve(EngineDiscoveryRequestResolver.java:113)
    at org.junit.jupiter.engine.discovery.DiscoverySelectorResolver.resolveSelectors(DiscoverySelectorResolver.java:46)
    at org.junit.jupiter.engine.JupiterTestEngine.discover(JupiterTestEngine.java:69)
    at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverEngineRoot(EngineDiscoveryOrchestrator.java:152)
    ... 13 more
Caused by: org.junit.platform.commons.PreconditionViolationException: Could not load class with name: org.merchant.poc.GeneratePdf
    at org.junit.platform.engine.discovery.MethodSelector.lambda$lazyLoadJavaClass$0(MethodSelector.java:157)
    at org.junit.platform.commons.function.Try$Failure.getOrThrow(Try.java:335)
    at org.junit.platform.engine.discovery.MethodSelector.lazyLoadJavaClass(MethodSelector.java:156)
    at org.junit.platform.engine.discovery.MethodSelector.getJavaClass(MethodSelector.java:135)
    at org.junit.jupiter.engine.discovery.MethodSelectorResolver.resolve(MethodSelectorResolver.java:73)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.lambda$resolve$2(EngineDiscoveryRequestResolution.java:146)
    at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
    at java.base/java.util.ArrayList$ArrayListSpliterator.tryAdvance(ArrayList.java:1602)
    at java.base/java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:129)
    at java.base/java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:527)
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:513)
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
    at java.base/java.util.stream.FindOps$FindOp.evaluateSequential(FindOps.java:150)
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
    at java.base/java.util.stream.ReferencePipeline.findFirst(ReferencePipeline.java:647)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:185)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:125)
    at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolveCompletely(EngineDiscoveryRequestResolution.java:91)
    ... 18 more
Caused by: java.lang.ClassNotFoundException: org.merchant.poc.GeneratePdf
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
    at org.junit.platform.commons.util.ReflectionUtils.lambda$tryToLoadClass$9(ReflectionUtils.java:829)
    at org.junit.platform.commons.function.Try.lambda$call$0(Try.java:57)
    at org.junit.platform.commons.function.Try.of(Try.java:93)
    at org.junit.platform.commons.function.Try.call(Try.java:57)
    at org.junit.platform.commons.util.ReflectionUtils.tryToLoadClass(ReflectionUtils.java:792)
    at org.junit.platform.commons.util.ReflectionUtils.tryToLoadClass(ReflectionUtils.java:748)
    ... 34 more

Do you know how this issue can be fixed?

EDIT:

import org.junit.jupiter.api.Test;

public class InvoiceTests {

    @Test
    public void generateTest()
    {
        System.out.println("test!");
    }

}

I tried this but again it's not working.

Solution 1:^[1]

What is the project structure you are following? I remember facing a similar issue when I started out, so basically what I did was just follow this structure:

project-dir
 -- src
     -- main
        -- java
            -- classes
     -- test
        -- java
            -- test-classes

In addition to the above structure, make sure you are naming your test classes in a correct format as mentioned in the above answer by @johanneslink

Solution 2:^[2]

I had issue this issue when I updgraded the versions of junit from 5.7.0 to 5.8.2. Try with version 5.7.0 for org.junit.jupiter:junit-jupiter-api and org.junit.jupiter:junit-jupiter-engine

Solution 3:^[3]

GeneratePdf does not match the default name pattern for test classes. The default pattern is Test*|*Test|*Tests.

You can change it in your Gradle file with

test {
  useJUnitPlatform()
  include '**/*Pdf'
}

Solution 4:^[4]

Environment :

IntelliJ
Java 17

I have faced the same issue after upgrading my project from JDK 11 to JDK 17 and junit-jupiter-api from 5.7.0 to 5.8.2.

On my project, the working version is 5.7.2

Follow the issue here : Github issue

Solution 5:^[5]

I got the same error because I'd named my integration test class as XyzIT, post renaming it to XyzIntegrationTest, it started working.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Vaibhav
Solution 2	Kowlown
Solution 3	johanneslink
Solution 4	AceneKASDI
Solution 5	ADJ

'org.junit.platform.commons.JUnitException: TestEngine with ID 'junit-jupiter' failed to discover tests

Solution 1:[1]

Solution 2:[2]

Solution 3:[3]

Solution 4:[4]

Solution 5:[5]