# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html
# For details: https://github.com/PyCQA/astroid/blob/main/LICENSE
# Copyright (c) https://github.com/PyCQA/astroid/blob/main/CONTRIBUTORS.txt
"""this module contains exceptions used in the astroid library
"""
from typing import TYPE_CHECKING
from astroid import util
if TYPE_CHECKING:
from astroid import nodes
__all__ = (
"AstroidBuildingError",
"AstroidBuildingException",
"AstroidError",
"AstroidImportError",
"AstroidIndexError",
"AstroidSyntaxError",
"AstroidTypeError",
"AstroidValueError",
"AttributeInferenceError",
"BinaryOperationError",
"DuplicateBasesError",
"InconsistentMroError",
"InferenceError",
"InferenceOverwriteError",
"MroError",
"NameInferenceError",
"NoDefault",
"NotFoundError",
"OperationError",
"ParentMissingError",
"ResolveError",
"StatementMissing",
"SuperArgumentTypeError",
"SuperError",
"TooManyLevelsError",
"UnaryOperationError",
"UnresolvableName",
"UseInferenceDefault",
)
[docs]class AstroidError(Exception):
"""base exception class for all astroid related exceptions
AstroidError and its subclasses are structured, intended to hold
objects representing state when the exception is thrown. Field
values are passed to the constructor as keyword-only arguments.
Each subclass has its own set of standard fields, but use your
best judgment to decide whether a specific exception instance
needs more or fewer fields for debugging. Field values may be
used to lazily generate the error message: self.message.format()
will be called with the field names and values supplied as keyword
arguments.
"""
def __init__(self, message="", **kws):
super().__init__(message)
self.message = message
for key, value in kws.items():
setattr(self, key, value)
def __str__(self):
return self.message.format(**vars(self))
[docs]class AstroidBuildingError(AstroidError):
"""exception class when we are unable to build an astroid representation
Standard attributes:
modname: Name of the module that AST construction failed for.
error: Exception raised during construction.
"""
def __init__(self, message="Failed to import module {modname}.", **kws):
super().__init__(message, **kws)
[docs]class AstroidImportError(AstroidBuildingError):
"""Exception class used when a module can't be imported by astroid."""
[docs]class TooManyLevelsError(AstroidImportError):
"""Exception class which is raised when a relative import was beyond the top-level.
Standard attributes:
level: The level which was attempted.
name: the name of the module on which the relative import was attempted.
"""
level = None
name = None
def __init__(
self,
message="Relative import with too many levels " "({level}) for module {name!r}",
**kws,
):
super().__init__(message, **kws)
[docs]class AstroidSyntaxError(AstroidBuildingError):
"""Exception class used when a module can't be parsed."""
[docs]class NoDefault(AstroidError):
"""raised by function's `default_value` method when an argument has
no default value
Standard attributes:
func: Function node.
name: Name of argument without a default.
"""
func = None
name = None
def __init__(self, message="{func!r} has no default for {name!r}.", **kws):
super().__init__(message, **kws)
[docs]class ResolveError(AstroidError):
"""Base class of astroid resolution/inference error.
ResolveError is not intended to be raised.
Standard attributes:
context: InferenceContext object.
"""
context = None
[docs]class MroError(ResolveError):
"""Error raised when there is a problem with method resolution of a class.
Standard attributes:
mros: A sequence of sequences containing ClassDef nodes.
cls: ClassDef node whose MRO resolution failed.
context: InferenceContext object.
"""
mros = ()
cls = None
def __str__(self):
mro_names = ", ".join(f"({', '.join(b.name for b in m)})" for m in self.mros)
return self.message.format(mros=mro_names, cls=self.cls)
[docs]class DuplicateBasesError(MroError):
"""Error raised when there are duplicate bases in the same class bases."""
[docs]class InconsistentMroError(MroError):
"""Error raised when a class's MRO is inconsistent."""
[docs]class SuperError(ResolveError):
"""Error raised when there is a problem with a *super* call.
Standard attributes:
*super_*: The Super instance that raised the exception.
context: InferenceContext object.
"""
super_ = None
def __str__(self):
return self.message.format(**vars(self.super_))
[docs]class InferenceError(ResolveError):
"""raised when we are unable to infer a node
Standard attributes:
node: The node inference was called on.
context: InferenceContext object.
"""
node = None
context = None
def __init__(self, message="Inference failed for {node!r}.", **kws):
super().__init__(message, **kws)
# Why does this inherit from InferenceError rather than ResolveError?
# Changing it causes some inference tests to fail.
[docs]class NameInferenceError(InferenceError):
"""Raised when a name lookup fails, corresponds to NameError.
Standard attributes:
name: The name for which lookup failed, as a string.
scope: The node representing the scope in which the lookup occurred.
context: InferenceContext object.
"""
name = None
scope = None
def __init__(self, message="{name!r} not found in {scope!r}.", **kws):
super().__init__(message, **kws)
[docs]class AttributeInferenceError(ResolveError):
"""Raised when an attribute lookup fails, corresponds to AttributeError.
Standard attributes:
target: The node for which lookup failed.
attribute: The attribute for which lookup failed, as a string.
context: InferenceContext object.
"""
target = None
attribute = None
def __init__(self, message="{attribute!r} not found on {target!r}.", **kws):
super().__init__(message, **kws)
[docs]class UseInferenceDefault(Exception):
"""exception to be raised in custom inference function to indicate that it
should go back to the default behaviour
"""
class _NonDeducibleTypeHierarchy(Exception):
"""Raised when is_subtype / is_supertype can't deduce the relation between two types."""
[docs]class AstroidIndexError(AstroidError):
"""Raised when an Indexable / Mapping does not have an index / key."""
[docs]class AstroidTypeError(AstroidError):
"""Raised when a TypeError would be expected in Python code."""
[docs]class AstroidValueError(AstroidError):
"""Raised when a ValueError would be expected in Python code."""
[docs]class InferenceOverwriteError(AstroidError):
"""Raised when an inference tip is overwritten
Currently only used for debugging.
"""
[docs]class ParentMissingError(AstroidError):
"""Raised when a node which is expected to have a parent attribute is missing one
Standard attributes:
target: The node for which the parent lookup failed.
"""
def __init__(self, target: "nodes.NodeNG") -> None:
self.target = target
super().__init__(message=f"Parent not found on {target!r}.")
[docs]class StatementMissing(ParentMissingError):
"""Raised when a call to node.statement() does not return a node. This is because
a node in the chain does not have a parent attribute and therefore does not
return a node for statement().
Standard attributes:
target: The node for which the parent lookup failed.
"""
def __init__(self, target: "nodes.NodeNG") -> None:
# pylint: disable-next=bad-super-call
# https://github.com/PyCQA/pylint/issues/2903
# https://github.com/PyCQA/astroid/pull/1217#discussion_r744149027
super(ParentMissingError, self).__init__(
message=f"Statement not found on {target!r}"
)
# Backwards-compatibility aliases
OperationError = util.BadOperationMessage
UnaryOperationError = util.BadUnaryOperationMessage
BinaryOperationError = util.BadBinaryOperationMessage
SuperArgumentTypeError = SuperError
UnresolvableName = NameInferenceError
NotFoundError = AttributeInferenceError
AstroidBuildingException = AstroidBuildingError