Error "TestEngine with ID 'junit-vintage' failed to discover tests" with Spring Boot 2.2

Question

I have a simple app using Spring Boot and Junit 5:

• When using Spring Boot 2.1 (e.g, 2.1.8 or 2.1.12), my unit tests run smoothly

• When using Spring Boot 2.2 (e.g., 2.2.2.RELEASE or 2.3.2.RELEASE) my unit tests fail with error message

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.22.2:test (default-test) on project XXX: There are test failures.
[ERROR]
[ERROR] Please refer to D:\Projets\workspace\XXX\target\surefire-reports for the individual test results.
[ERROR] Please refer to dump files (if any exist) [date].dump, [date]-jvmRun[N].dump and [date].dumpstream.
[ERROR] There was an error in the forked process
[ERROR] TestEngine with ID 'junit-vintage' failed to discover tests
[ERROR] org.apache.maven.surefire.booter.SurefireBooterForkException: There was an error in the forked process
[ERROR] TestEngine with ID 'junit-vintage' failed to discover tests
[ERROR]         at org.apache.maven.plugin.surefire.booterclient.ForkStarter.fork(ForkStarter.java:656)

I am using Maven 3.6.1, JDK 1.8, JUnit 5.6.0 and JUnit platform 1.6.0. I exclude the dependency on junit:junit from spring-boot-starter-test, so that I have no JUnit 4 artifacts left in the dependency tree. Note that both Spring Boot 2.2 and 2.3 use maven-surefire-plugin 2.22.2, so my problem does not originate from any regression of the maven-surefire-plugin.

Should I stick to Spring Boot 2.1 in order to have my unit test working?

Thanks in advance for your help.

Answer 1

I found the error. The dependency on spring-boot-starter-test brings a dependency on junit-vintage-engine. The latter must be excluded:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
    <exclusions>
        <exclusion>
            <groupId>org.junit.vintage</groupId>
            <artifactId>junit-vintage-engine</artifactId>
        </exclusion>
    </exclusions>
</dependency>

Answer 2

Adding the following dependency explicitly to upgrade junit-vintage-engine resolves the issue:

<dependency>
    <groupId>org.junit.vintage</groupId>
    <artifactId>junit-vintage-engine</artifactId>
    <version>5.7.0</version>
</dependency>

Answer 3

In my case (GRADLE and Spring Boot 2.x.x), adding exclusion for vintage worked

configurations {
    all {
        exclude(group = "junit", module = "junit")
        exclude(group = "org.junit.vintage", module = "junit-vintage-engine")
    }
}

Answer 4

For the reported error in the question or the below error, both relate to the same problem.

java.lang.NoClassDefFoundError: junit/runner/Version

This error occurs if the project excludes or not include JUnit 4 when it depends on spring-boot-starter-test. The spring-boot-starter-test depends on junit-vintage-engine by default. To resolve this issue either we have to exclude junit-vintage-engine Or should not depend on spring-boot-starter-test.

    testImplementation('org.springframework.boot:spring-boot-starter-test:2.2.2.RELEASE') {
        exclude group: 'junit'
        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
    }

    testImplementation('org.junit.jupiter:junit-jupiter-api:5.5.2')
    testImplementation('org.junit.jupiter:junit-jupiter-engine:5.5.2')
    testImplementation('org.junit.jupiter:junit-jupiter-params:5.5.2')

Answer 5

I had this issue as well. I've tried different solutions mentioned above, but nothing worked. The one that did work was the simple and ridiculous restart of Intellij.

Answer 6

I fixed the same error by using the Maven dependency analyzer and searching for 'junit'. A 1st party dependency (the red bar) was bringing in json-simple which was bringing in a 4.10 junit dependency. Simply excluding the 4.10 junit (right-click + Exclude) fixed it.

Answer 7

Excluding the dependencies is not an option for us. Because with that we don't have our tests run. So our solution was to downgrade the JUnit version:

<!--
  junit-vintage-engine 5.5.2 version does not support junit 4.13.1.
  If we try to use it, a parsing error is thrown.
  So we downgrade JUnit, so that junit-vintage-engine will handle it.
-->
<version.legacy.junit>4.13</version.legacy.junit>

Using Spring Boot 2.3.4 seems to be working.

Answer 8

Similar issue can be observed for "junit-jupiter" test engine, in case of running tests located inside java9 named modules (also for Spring Boot app). The message is the same without clue about the reason:

TestEngine with ID "junit-jupiter" failed to discover tests

The problem in this case is that one of your test classes requires named java9 module which is not required in your module-info.java.

To confirm this go to that particular module and execute build with -X option to enable debugging stacktraces. After that you will get more detailed information on the problem:

    [ERROR] org.apache.maven.surefire.booter.SurefireBooterForkException: There was an error in the forked process                                                                              
    [ERROR] TestEngine with ID 'junit-jupiter' failed to discover tests                                                                                                                         
    [ERROR] org.junit.platform.commons.JUnitException: TestEngine with ID 'junit-jupiter' failed to discover tests                                                                              
(...)                                                                                               
    [ERROR] Caused by: org.junit.platform.commons.JUnitException: ClassSelector [className = 'x.y.z.YourTest'] resolution failed                                                                                                                                                                  
    [ERROR]         at org.junit.platform.launcher.listeners.discovery.AbortOnFailureLauncherDiscoveryListener.selectorProcessed(AbortOnFailureLauncherDiscoveryListener.java:39)               
    (...)                                                                                                                                                 
    [ERROR] Caused by: java.lang.IllegalAccessError: class x.y.z.YourTest (in module com.your.module) cannot access class com.fasterxml.jackson.core.JsonProcessingException (in module com.fasterxml.jackson.core) because module com.bnymellon.rei.data.exchange.au
    th.service does not read module com.fasterxml.jackson.core   

As the message says jackson.core is not available and needs to be added to your module descriptor module-info.java:

open module com.your.module {
 (...)
  requires com.fasterxml.jackson.core;
  requires com.fasterxml.jackson.databind;
}
                                                                                                                         

NOTE: In example above you can see also jackson.databind added as subsequent exceptions (after you rerun maven build) would most probably suggest that this one is missing as well.

Answer 9

In my case in gradle this error was caused by having

testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine:${jUnitVersion}"

instead of

testImplementation "org.junit.jupiter:junit-jupiter-engine:${jUnitVersion}"

Answer 10

What solve my problem in this case, is changing Settings of IntelliJ, to use Gradle not Intellij as Gradle builder.

Answer 11

my solution removed following dependency:

<dependency>
    <groupId>junit-addons</groupId>
    <artifactId>junit-addons</artifactId>
    <scope>test</scope>
</dependency>

Answer 12

Already had the exclusion in my pom for junit-vintage-engine, but was encountering the issue. Did invalidate cache and restart in IntelliJ to make it work.

Answer 13

Another reason for this error message could be a mixed junit-version set:

After consistently switching from junit 5.6.2 to 5.7.2 fixes the error for me.

Answer 14

For me nothing from above worked. However, adding the latest version of JUnit from maven solved the issue for me.

Answer 15

The best option is to run the Maven test with debugging enabled:

e.g. mvn clean test -X. It will show the exact failure reason.

In my case, I was trying to run some Spock tests and the required Groovy XML dependency was not found (see stack trace below). It was solved when I added the Groovy dependency explicitly.

TestEngine with ID 'spock' failed to discover tests
org.junit.platform.commons.JUnitException: TestEngine with ID 'spock' failed to discover tests
        at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discoverEngineRoot(EngineDiscoveryOrchestrator.java:111)
        at org.junit.platform.launcher.core.EngineDiscoveryOrchestrator.discover(EngineDiscoveryOrchestrator.java:85)
        at org.junit.platform.launcher.core.DefaultLauncher.discover(DefaultLauncher.java:92)
        at org.junit.platform.launcher.core.DefaultLauncher.discover(DefaultLauncher.java:67)
        at org.apache.maven.surefire.junitplatform.TestPlanScannerFilter.accept(TestPlanScannerFilter.java:56)
        at org.apache.maven.surefire.api.util.DefaultScanResult.applyFilter(DefaultScanResult.java:102)
        at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.scanClasspath(JUnitPlatformProvider.java:147)
        at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invoke(JUnitPlatformProvider.java:128)
        at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:428)
        at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:162)
        at org.apache.maven.surefire.booter.ForkedBooter.run(ForkedBooter.java:562)
        at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:548)
Caused by: java.lang.NoClassDefFoundError: groovy/xml/MarkupBuilder
        at java.base/java.lang.Class.getDeclaredMethods0(Native Method)
...

Answer 16

I ran into this situation with a project that worked fine a few months ago, but when I went back the unit tests no longer worked within IntelliJ. I restarted IntelliJ, no change, updated IntelliJ and "Wala" error went away.