Simplified a i18n test.

    def test_extraction_error(self):

        os.chdir(self.test_dir)

        shutil.copyfile('./templates/template_with_error.tpl', './templates/template_with_error.html')

        self.assertRaises(SyntaxError, management.call_command, 'makemessages', locale=LOCALE, verbosity=0)

        self.assertRaises(SyntaxError, management.call_command, 'makemessages', locale=LOCALE, extensions=['tpl'], verbosity=0)

        with self.assertRaises(SyntaxError) as context_manager:

            management.call_command('makemessages', locale=LOCALE, verbosity=0)

            management.call_command('makemessages', locale=LOCALE, extensions=['tpl'], verbosity=0)

        self.assertRegexpMatches(str(context_manager.exception),

                r'Translation blocks must not include other block tags: blocktrans \(file templates[/\\]template_with_error\.html, line 3\)'

                r'Translation blocks must not include other block tags: blocktrans \(file templates[/\\]template_with_error\.tpl, line 3\)'

            )

        os.remove('./templates/template_with_error.html')

        # Check that the temporary file was cleaned up

        self.assertFalse(os.path.exists('./templates/template_with_error.html.py'))