MockitoJunitRunner can mock a Spring @Configuration class but all fields are null

Question

I have a Configuration class like this :

@Configuration
@ComponentScan(basePackages = "com.**.**") // production code, can't write package name
@EnableCaching
@PropertySource(value = { "classpath:application.properties", "classpath:version.txt"})
@EnableScheduling
public class AppConfig {

    @Value("${builtProfile}")
    @Nonnull
    private String activeProfile;

    ...
}

And this is the the test class :

@RunWith(MockitoJUnitRunner.class)
@ContextConfiguration(classes = {AppConfig.class, MvcConfiguration.class})
@ActiveProfiles("test")
public class NativeLoginServiceImplTest {

   @InjectMocks
   private NativeLoginServiceImpl nativeLoginServiceImpl;

   @Mock
   private AppConfig mAppConfiguration;

}

The mAppConfiguration is created during test but the problem is all of its fields are null. What wrong with my test setup and how can I make the correct one so Mockito can auto get these value in application.properties file for me?

Answer 1

I guess that for your fields you have at least getter methods. You should use when and thenReturn methods to make mocking work. Like this:

@Test
public void someTestMethod(){

    Mockito.when(mAppConfiguration.getActiveProfile()).thenReturn("some value");

    /** actual test goes here**/
}