| # Copyright (c) 2015 LOGILAB S.A. (Paris, FRANCE) <contact@logilab.fr> |
| # Copyright (c) 2016-2020 Claudiu Popa <pcmanticore@gmail.com> |
| # Copyright (c) 2016 Glenn Matthews <glmatthe@cisco.com> |
| # Copyright (c) 2018 Ville Skyttä <ville.skytta@iki.fi> |
| # Copyright (c) 2019-2021 Pierre Sassoulas <pierre.sassoulas@gmail.com> |
| # Copyright (c) 2020 hippo91 <guillaume.peillex@gmail.com> |
| # Copyright (c) 2020 Anthony Sottile <asottile@umich.edu> |
| |
| # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html |
| # For details: https://github.com/PyCQA/pylint/blob/master/LICENSE |
| |
| import astroid |
| |
| from pylint.checkers import BaseTokenChecker |
| from pylint.checkers.utils import check_messages |
| from pylint.interfaces import IAstroidChecker, ITokenChecker |
| |
| |
| class ElseifUsedChecker(BaseTokenChecker): |
| """Checks for use of "else if" when an "elif" could be used""" |
| |
| __implements__ = (ITokenChecker, IAstroidChecker) |
| name = "else_if_used" |
| msgs = { |
| "R5501": ( |
| 'Consider using "elif" instead of "else if"', |
| "else-if-used", |
| "Used when an else statement is immediately followed by " |
| "an if statement and does not contain statements that " |
| "would be unrelated to it.", |
| ) |
| } |
| |
| def __init__(self, linter=None): |
| BaseTokenChecker.__init__(self, linter) |
| self._init() |
| |
| def _init(self): |
| self._elifs = [] |
| self._if_counter = 0 |
| |
| def process_tokens(self, tokens): |
| # Process tokens and look for 'if' or 'elif' |
| for _, token, _, _, _ in tokens: |
| if token == "elif": |
| self._elifs.append(True) |
| elif token == "if": |
| self._elifs.append(False) |
| |
| def leave_module(self, _): |
| self._init() |
| |
| def visit_ifexp(self, node): |
| if isinstance(node.parent, astroid.FormattedValue): |
| return |
| self._if_counter += 1 |
| |
| def visit_comprehension(self, node): |
| self._if_counter += len(node.ifs) |
| |
| @check_messages("else-if-used") |
| def visit_if(self, node): |
| if isinstance(node.parent, astroid.If): |
| orelse = node.parent.orelse |
| # current if node must directly follow an "else" |
| if orelse and orelse == [node]: |
| if not self._elifs[self._if_counter]: |
| self.add_message("else-if-used", node=node) |
| self._if_counter += 1 |
| |
| |
| def register(linter): |
| """Required method to auto register this checker. |
| |
| :param linter: Main interface object for Pylint plugins |
| :type linter: Pylint object |
| """ |
| linter.register_checker(ElseifUsedChecker(linter)) |
