@Test
public void testDiff() {

    IChemObject atom1 = mock(IChemObject.class);
    IChemObject atom2 = mock(IChemObject.class);
    when(atom1.getFlags()).thenReturn(new boolean[]{false, false, false});
    when(atom2.getFlags()).thenReturn(new boolean[]{false, true, false});
    String result = ChemObjectDiff.diff(atom1, atom2);
    Assert.assertNotNull(result);
    Assert.assertNotSame("Expected non-zero-length result", 0, result.length());
    assertContains(result, "ChemObjectDiff");
    assertContains(result, "F/T");
}