# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html # For details: https://github.com/pylint-dev/pylint/blob/main/LICENSE # Copyright (c) https://github.com/pylint-dev/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, ) from pylint.interfaces import HIGH 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 " "an 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.", ), "W2603": ( "Exception groups are not supported by all versions included in the py-version setting", "using-exception-groups-in-unsupported-version", "Used when the py-version set by the user is lower than 3.11 and pylint encounters " "``except*`` or `ExceptionGroup``.", ), "W2604": ( "Generic type syntax (PEP 695) is not supported by all versions included in the py-version setting", "using-generic-type-syntax-in-unsupported-version", "Used when the py-version set by the user is lower than 3.12 and pylint encounters " "generic type syntax.", ), "W2605": ( "Assignment expression is not supported by all versions included in the py-version setting", "using-assignment-expression-in-unsupported-version", "Used when the py-version set by the user is lower than 3.8 and pylint encounters " "an assignment expression (walrus) operator.", ), "W2606": ( "Positional-only arguments are not supported by all versions included in the py-version setting", "using-positional-only-args-in-unsupported-version", "Used when the py-version set by the user is lower than 3.8 and pylint encounters " "positional-only arguments.", ), } 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) self._py311_plus = py_version >= (3, 11) self._py312_plus = py_version >= (3, 12) @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, confidence=HIGH ) @only_required_for_messages("using-assignment-expression-in-unsupported-version") def visit_namedexpr(self, node: nodes.JoinedStr) -> None: if not self._py38_plus: self.add_message( "using-assignment-expression-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-positional-only-args-in-unsupported-version") def visit_arguments(self, node: nodes.Arguments) -> None: if not self._py38_plus and node.posonlyargs: self.add_message( "using-positional-only-args-in-unsupported-version", node=node, confidence=HIGH, ) @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, confidence=HIGH, ) @only_required_for_messages("using-exception-groups-in-unsupported-version") def visit_trystar(self, node: nodes.TryStar) -> None: if not self._py311_plus: self.add_message( "using-exception-groups-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-exception-groups-in-unsupported-version") def visit_excepthandler(self, node: nodes.ExceptHandler) -> None: if ( not self._py311_plus and isinstance(node.type, nodes.Name) and node.type.name == "ExceptionGroup" ): self.add_message( "using-exception-groups-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-exception-groups-in-unsupported-version") def visit_raise(self, node: nodes.Raise) -> None: if ( not self._py311_plus and isinstance(node.exc, nodes.Call) and isinstance(node.exc.func, nodes.Name) and node.exc.func.name == "ExceptionGroup" ): self.add_message( "using-exception-groups-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-generic-type-syntax-in-unsupported-version") def visit_typealias(self, node: nodes.TypeAlias) -> None: if not self._py312_plus: self.add_message( "using-generic-type-syntax-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-generic-type-syntax-in-unsupported-version") def visit_typevar(self, node: nodes.TypeVar) -> None: if not self._py312_plus: self.add_message( "using-generic-type-syntax-in-unsupported-version", node=node, confidence=HIGH, ) @only_required_for_messages("using-generic-type-syntax-in-unsupported-version") def visit_typevartuple(self, node: nodes.TypeVarTuple) -> None: if not self._py312_plus: self.add_message( "using-generic-type-syntax-in-unsupported-version", node=node, confidence=HIGH, ) def register(linter: PyLinter) -> None: linter.register_checker(UnsupportedVersionChecker(linter))