Mocking Test Failed: Wanted but not invoked - junit5

Question

I'm trying to test updateUser() method from UserServiceImplementation class. For that, I'm using project-reactor test and JUnit5. When I test userUpdate(), I'm receiving Wanted but not invoked error. When I google it, I found out userRepository.save( ) is being called twice. I want to know why?
UserServiceImplementation Class
#Override
public Mono<User> updateUser(Long userId, UserDto userDto) {
return userRepository.findById(userId)
.flatMap(user -> {
User updateUser = UserMapper.USER_MAPPER_INSTANCE.toUser(userDto);
updateUser.setUserId(userId);
return userRepository.save(updateUser);
})
.map(Function.identity())
.switchIfEmpty(Mono.error(new Exception("User not found!")));
}
UserServiceImplementationTest Class
#Test
void updateUser() {
// given
Long userId = 1L;
String username = "user123";
UserDto userDto = new UserDto(
username,
"user user",
"user123#gmail.com",
LocalDate.now().toString(),
9843807187L,
"password",
Role.ADMIN
);
User user1 = new User(
1L,
username,
"password",
"user user",
"user123#gmail.com",
9843807187L,
LocalDate.now(),
Role.ADMIN
);
User userUpdate = new User(
1L,
username,
"password",
"user",
"user123#gmail.com",
9843807187L,
LocalDate.now(),
Role.ADMIN
);
//when
when(userRepository.findById(userId)).thenReturn(Mono.just(user1));
when(userRepository.save(any(User.class)))
.thenReturn(Mono.just(userUpdate));
// Then
Mono<User> updatedUser = serviceUnderTest.updateUser(userId, userDto);
StepVerifier.create(updatedUser)
.expectNext(userUpdate)
.verifyComplete();
verify(userRepository, times(1)).findById(userId);
verify(userRepository, times(1)).save(userUpdate);
}
Error
Wanted but not invoked:
userRepository.save(
User(userId=1, username=user123, password=password, name=user, email=user123#gmail.com, phNumber=9843807187, dateOfBirth=2023-02-06, role=ADMIN)
);
-> at com.alertSystem.service.UserServiceImplementationTest.updateUser(UserServiceImplementationTest.java:168)
However, there were exactly 2 interactions with this mock:
userRepository.findById(1L);
-> at com.alertSystem.service.UserServiceImplementation.updateUser(UserServiceImplementation.java:51)
userRepository.save(
User(userId=1, username=user123, password=password, name=user user, email=user123#gmail.com, phNumber=9843807187, dateOfBirth=2023-02-06, role=ADMIN)
);
-> at com.alertSystem.service.UserServiceImplementation.lambda$updateUser$0(UserServiceImplementation.java:55)
Wanted but not invoked:
userRepository.save(
User(userId=1, username=user123, password=password, name=user, email=user123#gmail.com, phNumber=9843807187, dateOfBirth=2023-02-06, role=ADMIN)
);
-> at com.alertSystem.service.UserServiceImplementationTest.updateUser(UserServiceImplementationTest.java:168)
However, there were exactly 2 interactions with this mock:
userRepository.findById(1L);
-> at com.alertSystem.service.UserServiceImplementation.updateUser(UserServiceImplementation.java:51)
userRepository.save(
User(userId=1, username=user123, password=password, name=user user, email=user123#gmail.com, phNumber=9843807187, dateOfBirth=2023-02-06, role=ADMIN)
);
-> at com.alertSystem.service.UserServiceImplementation.lambda$updateUser$0(UserServiceImplementation.java:55)
at com.alertSystem.service.UserServiceImplementationTest.updateUser(UserServiceImplementationTest.java:168)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:727)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:156)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:147)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:86)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(InterceptingExecutableInvoker.java:103)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.lambda$invoke$0(InterceptingExecutableInvoker.java:93)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:92)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:86)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7(TestMethodTestDescriptor.java:217)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:213)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:138)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:68)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:151)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:147)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:127)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:90)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:55)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:102)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:54)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:114)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86)
at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86)
at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:53)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:57)
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)

Answer 1

userRepository.save( ) is not being called twice. It said that there are two interactions with userRepository - find and save. The reason of error is probably that entities you are comparing in the test are not equal. Try to add or double check equals method and object which you are comparing with.