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 signal_handler_mapping(self):
        """A dict mapping (signal number) -> (a method handling the signal)."""
        # Could use an enum here, but we never end up doing any matching on the specific signal value,
        # instead just iterating over the registered signals to set handlers, so a dict is probably
        # better.
        return {
            signal.SIGINT: self._handle_sigint_if_enabled,
            signal.SIGQUIT: self.handle_sigquit,
            signal.SIGTERM: self.handle_sigterm,
        }