# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html # For details: https://github.com/PyCQA/pylint/blob/main/LICENSE # Copyright (c) https://github.com/PyCQA/pylint/blob/main/CONTRIBUTORS.txt """Checker for features used that are not supported by all python versions indicated by the py-version setting. """ from __future__ import annotations from typing import TYPE_CHECKING from astroid import nodes from pylint.checkers import BaseChecker from pylint.checkers.utils import ( only_required_for_messages, safe_infer, uninferable_final_decorators, ) if TYPE_CHECKING: from pylint.lint import PyLinter class UnsupportedVersionChecker(BaseChecker): """Checker for features that are not supported by all python versions indicated by the py-version setting. """ name = "unsupported_version" msgs = { "W2601": ( "F-strings are not supported by all versions included in the py-version setting", "using-f-string-in-unsupported-version", "Used when the py-version set by the user is lower than 3.6 and pylint encounters " "a f-string.", ), "W2602": ( "typing.final is not supported by all versions included in the py-version setting", "using-final-decorator-in-unsupported-version", "Used when the py-version set by the user is lower than 3.8 and pylint encounters " "a ``typing.final`` decorator.", ), } def open(self) -> None: """Initialize visit variables and statistics.""" py_version = self.linter.config.py_version self._py36_plus = py_version >= (3, 6) self._py38_plus = py_version >= (3, 8) @only_required_for_messages("using-f-string-in-unsupported-version") def visit_joinedstr(self, node: nodes.JoinedStr) -> None: """Check f-strings.""" if not self._py36_plus: self.add_message("using-f-string-in-unsupported-version", node=node) @only_required_for_messages("using-final-decorator-in-unsupported-version") def visit_decorators(self, node: nodes.Decorators) -> None: """Check decorators.""" self._check_typing_final(node) def _check_typing_final(self, node: nodes.Decorators) -> None: """Add a message when the `typing.final` decorator is used and the py-version is lower than 3.8. """ if self._py38_plus: return decorators = [] for decorator in node.get_children(): inferred = safe_infer(decorator) if inferred and inferred.qname() == "typing.final": decorators.append(decorator) for decorator in decorators or uninferable_final_decorators(node): self.add_message( "using-final-decorator-in-unsupported-version", node=decorator ) def register(linter: PyLinter) -> None: linter.register_checker(UnsupportedVersionChecker(linter))