Different mocks are used for @Mock and @InjectMock in the same test class with JUnit 5 extension

I’ve been playing with the new JUnit 5 support in Mockito 2.17.0. I have found that with @Mock and @InjectMocks used in the same test class different mocks are injected. I would expect to have the same mock reused (as it works with JUnit 4 or manual @Mock initialization).

Sample code:

@ExtendWith(MockitoExtension.class)
public class SpaceShip5BugMiniTest {

    @InjectMocks
    private SpaceShip spaceShip;

    @Mock
    private TacticalStation tacticalStation;

    @Test
    public void shouldInjectMocks() {
        assertThat(tacticalStation).isNotNull();
        assertThat(spaceShip.getTacticalStation()).isEqualTo(tacticalStation);  
        //Bug ↑ - different mocks are use in @Mock and @InjectMock
    }
}

Error message:

org.opentest4j.AssertionFailedError: 
Expecting:
 <"tacticalStation (TacticalStation$MockitoMock$991606095@61d6015a)">
to be equal to:
 <"tacticalStation (TacticalStation$MockitoMock$991606095@b62d79)">
but was not.
Expected :tacticalStation
Actual   :tacticalStation

The minimal (non-)working example is available here.

@TimvdLippe Do you have an idea what could be wrong?

Mockito 2.17.0 (2.17.1 is not being released due to (https://github.com/mockito/shipkit/issues/679), junit-jupiter 5.1.0, OpenJDK 1.8.0_161, Linux.

Checklist:

• The mockito message in the stacktrace have useful information, but it didn’t help
• The problematic code (if that’s possible) is copied here; Note that some configuration are impossible to mock via Mockito
• Provide versions (mockito / jdk / os / any other relevant information)
• Provide a Short, Self Contained, Correct (Compilable), Example of the issue (same as any question on stackoverflow.com)
• Read the contributing guide

[szpak]

It works flawlessly. Thanks @SeriyBg!

@TimvdLippe As this bug can impact all those people preferring a constructor injection, what do you thing about releasing the new minor version (e.g. after #1350 is hopefully merged 😃 ) to Maven Central?

[karthikairam]

I’m seeing this same bug when using SpringExtension.class along with MockitoExtension.class:

@ExtendWith({MockitoExtension.class, SpringExtension.class})
public class InjectMocksTest {
  static class TacticalStation {}

  static class SpaceShip {
    private final TacticalStation tacticalStation;

    public SpaceShip(final TacticalStation tacticalStation) {
      this.tacticalStation = tacticalStation;
    }

    public TacticalStation getTacticalStation() {
      return tacticalStation;
    }
  }

  @InjectMocks
  private SpaceShip spaceShip;

  @Mock
  private TacticalStation tacticalStation;

  @Test
  public void shouldInjectMocks() {
    assertThat(tacticalStation).isNotNull();
    assertThat(spaceShip.getTacticalStation()).isEqualTo(tacticalStation);
    //Bug ↑ - different mocks are use in @Mock and @InjectMock
  }
}

This is using Mockito 3.1.0, JUnit 5.6.0, and Spring Boot 5.3.0.RELEASE.

Yes I am also facing this issue. Mine is also exactly the same scenario. Below are my dependencies, org.junit.jupiter:junit-jupiter-engine:5.6.0 org.springframework.boot:spring-boot-starter:2.2.6.RELEASE org.springframework.boot:spring-boot-starter-test:2.2.6.RELEASE org.mockito:mockito-junit-jupiter:3.1.0