@Test
public void test_addUserToSafe_failure_400() {

    String token = "5PDrOhsy4ig8L3EpsJZSLAMg";
    String path = "shared/mysafe01";
    SafeUser safeUser = new SafeUser(path, "testuser1","write");
    UserDetails userDetails = new UserDetails();
    userDetails.setUsername("testuser1");
    
    ResponseEntity<String> responseEntityExpected = ResponseEntity.status(HttpStatus.BAD_REQUEST).body("{\"errors\":[\"Invalid input values\"]}");
    when(ControllerUtil.areSafeUserInputsValid(safeUser)).thenReturn(false);
    when(safeUtils.canAddOrRemoveUser(userDetails, safeUser, "addUser")).thenReturn(true);
    
    ResponseEntity<String> responseEntity = safesService.addUserToSafe(token, safeUser, null);
    assertEquals(HttpStatus.BAD_REQUEST, responseEntity.getStatusCode());
    assertEquals(responseEntityExpected, responseEntity);
}