Method test_empty_ff

tests/test_black.py:139–147

(self)

    invokeBlack = staticmethod(invokeBlack)

    def test_empty_ff(self) -> None:
        expected = ""
        tmp_file = Path(black.dump_to_file())
        try:
            self.assertFalse(ff(tmp_file, write_back=black.WriteBack.YES))
            actual = tmp_file.read_text(encoding="utf-8")
        finally:
            os.unlink(tmp_file)
        self.assertFormatEqual(expected, actual)

    @patch("black.dump_to_file", dump_to_stderr)
    def test_one_empty_line(self) -> None: