def test_check_no_download(self):
        """ensures 'selfupdate --check' does not download anything."""
        output = self.run_command("selfupdate --check", exitcode=0)
        contains_latest_version = ("Already at latest version" in output)
        contains_new_version = ("New version available" in output)
        assert (contains_latest_version or contains_new_version)
        self.assertNotIn("Url: ", output)
        self.assertNotIn("Update completed.", output)
        self.assertNotIn("Failed to update. Please try again.", output)
ensures 'selfupdate --check' does not download anything.
tests/misc/test_selfupdate.py