| # Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html |
| # For details: https://github.com/pylint-dev/astroid/blob/main/LICENSE |
| # Copyright (c) https://github.com/pylint-dev/astroid/blob/main/CONTRIBUTORS.txt |
| |
| |
| from __future__ import annotations |
| |
| import warnings |
| from typing import TYPE_CHECKING, Any, Final, Literal |
| |
| from astroid.exceptions import InferenceError |
| |
| if TYPE_CHECKING: |
| from astroid import bases, nodes |
| from astroid.context import InferenceContext |
| from astroid.typing import InferenceResult |
| |
| |
| class UninferableBase: |
| """Special inference object, which is returned when inference fails. |
| |
| This is meant to be used as a singleton. Use astroid.util.Uninferable to access it. |
| """ |
| |
| def __repr__(self) -> Literal["Uninferable"]: |
| return "Uninferable" |
| |
| __str__ = __repr__ |
| |
| def __getattribute__(self, name: str) -> Any: |
| if name == "next": |
| raise AttributeError("next method should not be called") |
| if name.startswith("__") and name.endswith("__"): |
| return object.__getattribute__(self, name) |
| if name == "accept": |
| return object.__getattribute__(self, name) |
| return self |
| |
| def __call__(self, *args: Any, **kwargs: Any) -> UninferableBase: |
| return self |
| |
| def __bool__(self) -> Literal[False]: |
| return False |
| |
| __nonzero__ = __bool__ |
| |
| def accept(self, visitor): |
| return visitor.visit_uninferable(self) |
| |
| |
| Uninferable: Final = UninferableBase() |
| |
| |
| class BadOperationMessage: |
| """Object which describes a TypeError occurred somewhere in the inference chain. |
| |
| This is not an exception, but a container object which holds the types and |
| the error which occurred. |
| """ |
| |
| |
| class BadUnaryOperationMessage(BadOperationMessage): |
| """Object which describes operational failures on UnaryOps.""" |
| |
| def __init__(self, operand, op, error): |
| self.operand = operand |
| self.op = op |
| self.error = error |
| |
| @property |
| def _object_type_helper(self): |
| from astroid import helpers # pylint: disable=import-outside-toplevel |
| |
| return helpers.object_type |
| |
| def _object_type(self, obj): |
| objtype = self._object_type_helper(obj) |
| if isinstance(objtype, UninferableBase): |
| return None |
| |
| return objtype |
| |
| def __str__(self) -> str: |
| if hasattr(self.operand, "name"): |
| operand_type = self.operand.name |
| else: |
| object_type = self._object_type(self.operand) |
| if hasattr(object_type, "name"): |
| operand_type = object_type.name |
| else: |
| # Just fallback to as_string |
| operand_type = object_type.as_string() |
| |
| msg = "bad operand type for unary {}: {}" |
| return msg.format(self.op, operand_type) |
| |
| |
| class BadBinaryOperationMessage(BadOperationMessage): |
| """Object which describes type errors for BinOps.""" |
| |
| def __init__(self, left_type, op, right_type): |
| self.left_type = left_type |
| self.right_type = right_type |
| self.op = op |
| |
| def __str__(self) -> str: |
| msg = "unsupported operand type(s) for {}: {!r} and {!r}" |
| return msg.format(self.op, self.left_type.name, self.right_type.name) |
| |
| |
| def _instancecheck(cls, other) -> bool: |
| wrapped = cls.__wrapped__ |
| other_cls = other.__class__ |
| is_instance_of = wrapped is other_cls or issubclass(other_cls, wrapped) |
| warnings.warn( |
| "%r is deprecated and slated for removal in astroid " |
| "2.0, use %r instead" % (cls.__class__.__name__, wrapped.__name__), |
| PendingDeprecationWarning, |
| stacklevel=2, |
| ) |
| return is_instance_of |
| |
| |
| def check_warnings_filter() -> bool: |
| """Return True if any other than the default DeprecationWarning filter is enabled. |
| |
| https://docs.python.org/3/library/warnings.html#default-warning-filter |
| """ |
| return any( |
| issubclass(DeprecationWarning, filter[2]) |
| and filter[0] != "ignore" |
| and filter[3] != "__main__" |
| for filter in warnings.filters |
| ) |
| |
| |
| def safe_infer( |
| node: nodes.NodeNG | bases.Proxy | UninferableBase, |
| context: InferenceContext | None = None, |
| ) -> InferenceResult | None: |
| """Return the inferred value for the given node. |
| |
| Return None if inference failed or if there is some ambiguity (more than |
| one node has been inferred). |
| """ |
| if isinstance(node, UninferableBase): |
| return node |
| try: |
| inferit = node.infer(context=context) |
| value = next(inferit) |
| except (InferenceError, StopIteration): |
| return None |
| try: |
| next(inferit) |
| return None # None if there is ambiguity on the inferred node |
| except InferenceError: |
| return None # there is some kind of ambiguity |
| except StopIteration: |
| return value |