source: class BookmarkViewModelTest {
  
      private BookmarkViewModel viewModel;
      @Mock
      private AcademyRepository academyRepository;
  
      @Test
      public void getBookmark() {
  
target:         when(academyRepository.getBookmarkedCourses()).thenReturn(DataDummy.generateDummyCourses());
          List<CourseEntity> courseEntities = viewModel.getBookmarks();
          verify(academyRepository).getBookmarkedCourses();
          assertNotNull(courseEntities);
          assertEquals(5, courseEntities.size());
      }
  
  }