When spring boot integrates with mybatisplus to add database, junit startup reports the following error

java.lang.NoClassDefFoundError: org/springframework/core/annotation/MergedAnnotations$SearchStrategy

    at org.springframework.test.context.support.TestPropertySourceUtils.buildMergedTestPropertySources(TestPropertySourceUtils.java:74)
    at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildMergedContextConfiguration(AbstractTestContextBootstrapper.java:386)
    at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildDefaultMergedContextConfiguration(AbstractTestContextBootstrapper.java:312)
    at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildMergedContextConfiguration(AbstractTestContextBootstrapper.java:265)
    at org.springframework.test.context.support.AbstractTestContextBootstrapper.buildTestContext(AbstractTestContextBootstrapper.java:108)
    at org.springframework.boot.test.context.SpringBootTestContextBootstrapper.buildTestContext(SpringBootTestContextBootstrapper.java:82)
    at org.springframework.test.context.TestContextManager.<init>(TestContextManager.java:137)
    at org.springframework.test.context.TestContextManager.<init>(TestContextManager.java:122)
    at org.springframework.test.context.junit4.SpringJUnit4Cla***unner.createTestContextManager(SpringJUnit4Cla***unner.java:151)
    at org.springframework.test.context.junit4.SpringJUnit4Cla***unner.<init>(SpringJUnit4Cla***unner.java:142)
    at org.springframework.test.context.junit4.SpringRunner.<init>(SpringRunner.java:49)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
    at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
    at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
    at org.junit.internal.requests.Cla***equest.getRunner(Cla***equest.java:33)
    at org.junit.internal.requests.FilterRequest.getRunner(FilterRequest.java:36)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:49)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.ClassNotFoundException: org.springframework.core.annotation.MergedAnnotations$SearchStrategy
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 26 more

The reason is that spring core dependency is not introduced into pom file. The solution is as follows: it is recommended to be consistent with spring test version

It turns out that another error has been reported

I checked this for a long time. It said that there was a conflict between the versions of springboot and springcloud. I used springboot-2.1.8 ，springcloud-Greenwich.SR3 , it's a match. After a lot of checking, it's found that my test package conflicts

The long-standing problem has finally been solved