# 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
"""This module contains exceptions used in the astroid library."""
from __future__ import annotations
from collections.abc import Iterable, Iterator
from typing import TYPE_CHECKING, Any
from astroid.typing import InferenceResult, SuccessfulInferenceResult
if TYPE_CHECKING:
from astroid import arguments, bases, nodes, objects
from astroid.context import InferenceContext
__all__ = (
"AstroidBuildingError",
"AstroidError",
"AstroidImportError",
"AstroidIndexError",
"AstroidSyntaxError",
"AstroidTypeError",
"AstroidValueError",
"AttributeInferenceError",
"DuplicateBasesError",
"InconsistentMroError",
"InferenceError",
"InferenceOverwriteError",
"MroError",
"NameInferenceError",
"NoDefault",
"NotFoundError",
"ParentMissingError",
"ResolveError",
"StatementMissing",
"SuperArgumentTypeError",
"SuperError",
"TooManyLevelsError",
"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: str = "", **kws: Any) -> None:
super().__init__(message)
self.message = message
for key, value in kws.items():
setattr(self, key, value)
def __str__(self) -> str:
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: str = "Failed to import module {modname}.",
modname: str | None = None,
error: Exception | None = None,
source: str | None = None,
path: str | None = None,
cls: type | None = None,
class_repr: str | None = None,
**kws: Any,
) -> None:
self.modname = modname
self.error = error
self.source = source
self.path = path
self.cls = cls
self.class_repr = class_repr
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.
"""
def __init__(
self,
message: str = "Relative import with too many levels "
"({level}) for module {name!r}",
level: int | None = None,
name: str | None = None,
**kws: Any,
) -> None:
self.level = level
self.name = name
super().__init__(message, **kws)
[docs]
class AstroidSyntaxError(AstroidBuildingError):
"""Exception class used when a module can't be parsed."""
def __init__(
self,
message: str,
modname: str | None,
error: Exception,
path: str | None,
source: str | None = None,
) -> None:
super().__init__(message, modname, error, source, path)
[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.
"""
def __init__(
self,
message: str = "{func!r} has no default for {name!r}.",
func: nodes.FunctionDef | None = None,
name: str | None = None,
**kws: Any,
) -> None:
self.func = func
self.name = name
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.
"""
def __init__(
self, message: str = "", context: InferenceContext | None = None, **kws: Any
) -> None:
self.context = context
super().__init__(message, **kws)
[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.
"""
def __init__(
self,
message: str,
mros: Iterable[Iterable[nodes.ClassDef]],
cls: nodes.ClassDef,
context: InferenceContext | None = None,
**kws: Any,
) -> None:
self.mros = mros
self.cls = cls
self.context = context
super().__init__(message, **kws)
def __str__(self) -> str:
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.
"""
def __init__(self, message: str, super_: objects.Super, **kws: Any) -> None:
self.super_ = super_
super().__init__(message, **kws)
def __str__(self) -> str:
return self.message.format(**vars(self.super_))
[docs]
class InferenceError(ResolveError): # pylint: disable=too-many-instance-attributes
"""Raised when we are unable to infer a node.
Standard attributes:
node: The node inference was called on.
context: InferenceContext object.
"""
def __init__( # pylint: disable=too-many-arguments
self,
message: str = "Inference failed for {node!r}.",
node: InferenceResult | None = None,
context: InferenceContext | None = None,
target: InferenceResult | None = None,
targets: InferenceResult | None = None,
attribute: str | None = None,
unknown: InferenceResult | None = None,
assign_path: list[int] | None = None,
caller: SuccessfulInferenceResult | None = None,
stmts: Iterator[InferenceResult] | None = None,
frame: InferenceResult | None = None,
call_site: arguments.CallSite | None = None,
func: InferenceResult | None = None,
arg: str | None = None,
positional_arguments: list | None = None,
unpacked_args: list | None = None,
keyword_arguments: dict | None = None,
unpacked_kwargs: dict | None = None,
**kws: Any,
) -> None:
self.node = node
self.context = context
self.target = target
self.targets = targets
self.attribute = attribute
self.unknown = unknown
self.assign_path = assign_path
self.caller = caller
self.stmts = stmts
self.frame = frame
self.call_site = call_site
self.func = func
self.arg = arg
self.positional_arguments = positional_arguments
self.unpacked_args = unpacked_args
self.keyword_arguments = keyword_arguments
self.unpacked_kwargs = unpacked_kwargs
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.
"""
def __init__(
self,
message: str = "{name!r} not found in {scope!r}.",
name: str | None = None,
scope: nodes.LocalsDictNodeNG | None = None,
context: InferenceContext | None = None,
**kws: Any,
) -> None:
self.name = name
self.scope = scope
self.context = context
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.
"""
def __init__(
self,
message: str = "{attribute!r} not found on {target!r}.",
attribute: str = "",
target: nodes.NodeNG | bases.BaseInstance | None = None,
context: InferenceContext | None = None,
mros: list[nodes.ClassDef] | None = None,
super_: nodes.ClassDef | None = None,
cls: nodes.ClassDef | None = None,
**kws: Any,
) -> None:
self.attribute = attribute
self.target = target
self.context = context
self.mros = mros
self.super_ = super_
self.cls = cls
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."""
def __init__(
self,
message: str = "",
node: nodes.NodeNG | bases.Instance | None = None,
index: nodes.Subscript | None = None,
context: InferenceContext | None = None,
**kws: Any,
) -> None:
self.node = node
self.index = index
self.context = context
super().__init__(message, **kws)
[docs]
class AstroidTypeError(AstroidError):
"""Raised when a TypeError would be expected in Python code."""
def __init__(
self,
message: str = "",
node: nodes.NodeNG | bases.Instance | None = None,
index: nodes.Subscript | None = None,
context: InferenceContext | None = None,
**kws: Any,
) -> None:
self.node = node
self.index = index
self.context = context
super().__init__(message, **kws)
[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:
super(ParentMissingError, self).__init__(
message=f"Statement not found on {target!r}"
)
SuperArgumentTypeError = SuperError
UnresolvableName = NameInferenceError
NotFoundError = AttributeInferenceError