def onShortcutUnindentWithBackspace(self):
        """Backspace pressed, unindent
        """
        assert self._qpart.textBeforeCursor().endswith(self.text())

        charsToRemove = len(self._qpart.textBeforeCursor()) % len(self.text())
        if charsToRemove == 0:
            charsToRemove = len(self.text())

        cursor = self._qpart.textCursor()
        cursor.setPosition(cursor.position() - charsToRemove, QTextCursor.KeepAnchor)
        cursor.removeSelectedText()
def _reset_exiter(cls, exiter: Optional[Exiter]) -> None:
        """Class state:

        - Overwrites `cls._exiter`.
        Python state:
        - Overwrites sys.excepthook.
        """
        logger.debug(f"overriding the global exiter with {exiter} (from {cls._exiter})")
        # NB: mutate the class variables! This is done before mutating the exception hook, because the
        # uncaught exception handler uses cls._exiter to exit.
        cls._exiter = exiter
        # NB: mutate process-global state!
        sys.excepthook = cls._log_unhandled_exception_and_exit