test_fileinput.py 文件源码

def test_opening_mode(self):
        try:
            # invalid mode, should raise ValueError
            fi = FileInput(mode="w")
            self.fail("FileInput should reject invalid mode argument")
        except ValueError:
            pass
        t1 = None
        try:
            # try opening in universal newline mode
            t1 = writeTmp(1, [b"A\nB\r\nC\rD"], mode="wb")
            with check_warnings(('', DeprecationWarning)):
                fi = FileInput(files=t1, mode="U")
            with check_warnings(('', DeprecationWarning)):
                lines = list(fi)
            self.assertEqual(lines, ["A\n", "B\n", "C\n", "D"])
        finally:
            remove_tempfiles(t1)