@Test
public void testFindIdByUsername() {

	// Arrange
	final Patient patient = mock(Patient.class);
	when(patientRepository.findByUsername(anyString())).thenReturn(patient);
	final Long expectedId = new Long(100);
	when(patient.getId()).thenReturn(expectedId);
	// Act
	Long result = sut.findIdByUsername(anyString());
	// Assert
	assertEquals(expectedId, result);
}