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# 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
"""Check for new / old style related problems."""
from __future__ import annotations
from typing import TYPE_CHECKING
import astroid
from astroid import nodes
from pylint.checkers import BaseChecker
from pylint.checkers.utils import (
has_known_bases,
node_frame_class,
only_required_for_messages,
)
from pylint.typing import MessageDefinitionTuple
if TYPE_CHECKING:
from pylint.lint import PyLinter
MSGS: dict[str, MessageDefinitionTuple] = {
"E1003": (
"Bad first argument %r given to super()",
"bad-super-call",
"Used when another argument than the current class is given as "
"first argument of the super builtin.",
)
}
class NewStyleConflictChecker(BaseChecker):
"""Checks for usage of new style capabilities on old style classes and
other new/old styles conflicts problems.
* use of property, __slots__, super
* "super" usage
"""
# configuration section name
name = "newstyle"
# messages
msgs = MSGS
# configuration options
options = ()
@only_required_for_messages("bad-super-call")
def visit_functiondef(self, node: nodes.FunctionDef) -> None:
"""Check use of super."""
# ignore actual functions or method within a new style class
if not node.is_method():
return
klass = node.parent.frame(future=True)
for stmt in node.nodes_of_class(nodes.Call):
if node_frame_class(stmt) != node_frame_class(node):
# Don't look down in other scopes.
continue
expr = stmt.func
if not isinstance(expr, nodes.Attribute):
continue
call = expr.expr
# skip the test if using super
if not (
isinstance(call, nodes.Call)
and isinstance(call.func, nodes.Name)
and call.func.name == "super"
):
continue
# super should not be used on an old style class
if klass.newstyle or not has_known_bases(klass):
# super first arg should not be the class
if not call.args:
continue
# calling super(type(self), self) can lead to recursion loop
# in derived classes
arg0 = call.args[0]
if (
isinstance(arg0, nodes.Call)
and isinstance(arg0.func, nodes.Name)
and arg0.func.name == "type"
):
self.add_message("bad-super-call", node=call, args=("type",))
continue
# calling super(self.__class__, self) can lead to recursion loop
# in derived classes
if (
len(call.args) >= 2
and isinstance(call.args[1], nodes.Name)
and call.args[1].name == "self"
and isinstance(arg0, nodes.Attribute)
and arg0.attrname == "__class__"
):
self.add_message(
"bad-super-call", node=call, args=("self.__class__",)
)
continue
try:
supcls = call.args and next(call.args[0].infer(), None)
except astroid.InferenceError:
continue
# If the supcls is in the ancestors of klass super can be used to skip
# a step in the mro() and get a method from a higher parent
if klass is not supcls and all(i != supcls for i in klass.ancestors()):
name = None
# if supcls is not Uninferable, then supcls was inferred
# and use its name. Otherwise, try to look
# for call.args[0].name
if supcls:
name = supcls.name
elif call.args and hasattr(call.args[0], "name"):
name = call.args[0].name
if name:
self.add_message("bad-super-call", node=call, args=(name,))
visit_asyncfunctiondef = visit_functiondef
def register(linter: PyLinter) -> None:
linter.register_checker(NewStyleConflictChecker(linter))
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