Returns the line number from the y_pos.

        :param y_pos: Y pos in the editor
        :return: Line number (0 based), -1 if out of range

def line_nbr_from_position(self, y_pos):
        """
        Returns the line number from the y_pos.

        :param y_pos: Y pos in the editor
        :return: Line number (0 based), -1 if out of range
        """
        editor = self._editor
        height = editor.fontMetrics().height()
        for top, line, block in editor.visible_blocks:
            if top <= y_pos <= top + height:
                return line
        return -1