@Test
  public void testGetContainersByStatusResultsDifferent() {
    Set<Container> primaryResult = new HashSet<>(Collections.singletonList(testContainer));
    Set<Container> secondaryResult = new HashSet<>();
    when(primaryAccountService.getContainersByStatus(any())).thenReturn(primaryResult);
    when(secondaryAccountService.getContainersByStatus(any())).thenReturn(secondaryResult);
    assertEquals("", primaryResult, compositeAccountService.getContainersByStatus(Container.ContainerStatus.ACTIVE));
    verify(primaryAccountService).getContainersByStatus(Container.ContainerStatus.ACTIVE);
    verify(secondaryAccountService).getContainersByStatus(Container.ContainerStatus.ACTIVE);
  }
Test composite getContainersByStatus() with both sources returning different results.
ambry-account/src/test/java/com/github/ambry/account/CompositeAccountServiceTest.java