def METHOD_NAME(self, basename, original, expected, first_differing):
    original_lines = self._split(original)
    expected_lines = self._split(expected)
    dut = IncludeFormatter(
        "drake/dummy/" + basename,
        readlines=original_lines)
    dut.format_includes()
    self.assertEqual(dut.get_all_lines(), expected_lines)
    self.assertEqual(dut.get_first_differing_original_index(),
                     first_differing)