mirror of
https://fuchsia.googlesource.com/third_party/github.com/pylint-dev/pylint
synced 2024-09-21 16:19:21 +00:00
82 lines
3.2 KiB
Python
82 lines
3.2 KiB
Python
|
# -*- coding: utf-8 -*-
|
||
|
|
|
||
|
|
# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
|
||
|
|
# For details: https://github.com/PyCQA/pylint/blob/master/COPYING
|
||
|
|
|
||
|
|
"""Looks for overlapping exceptions."""
|
||
|
|
|
||
|
|
import astroid
|
||
|
|
|
||
|
|
from pylint import interfaces
|
||
|
|
from pylint import checkers
|
||
|
|
from pylint.checkers import utils
|
||
|
|
|
||
|
|
from pylint.checkers.exceptions import _annotated_unpack_infer
|
||
|
|
|
||
|
|
|
||
|
|
class OverlappingExceptionsChecker(checkers.BaseChecker):
|
||
|
|
"""Checks for two or more exceptions in the same exception handler
|
||
|
|
clause that are identical or parts of the same inheritence hierarchy
|
||
|
|
(i.e. overlapping)."""
|
||
|
|
|
||
|
|
__implements__ = interfaces.IAstroidChecker
|
||
|
|
|
||
|
|
name = 'overlap-except'
|
||
|
|
msgs = {'W0714': ('Overlapping exceptions (%s)',
|
||
|
|
'overlapping-except',
|
||
|
|
'Used when exceptions in handler overlap or are identical')}
|
||
|
|
priority = -2
|
||
|
|
options = ()
|
||
|
|
|
||
|
|
@utils.check_messages('overlapping-except')
|
||
|
|
def visit_tryexcept(self, node):
|
||
|
|
"""check for empty except"""
|
||
|
|
for _, handler in enumerate(node.handlers):
|
||
|
|
if handler.type is None:
|
||
|
|
continue
|
||
|
|
if isinstance(handler.type, astroid.BoolOp):
|
||
|
|
continue
|
||
|
|
try:
|
||
|
|
excs = list(_annotated_unpack_infer(handler.type))
|
||
|
|
except astroid.InferenceError:
|
||
|
|
continue
|
||
|
|
|
||
|
|
handled_in_clause = []
|
||
|
|
for part, exc in excs:
|
||
|
|
if exc is astroid.YES:
|
||
|
|
continue
|
||
|
|
if (isinstance(exc, astroid.Instance) and
|
||
|
|
utils.inherit_from_std_ex(exc)):
|
||
|
|
# pylint: disable=protected-access
|
||
|
|
exc = exc._proxied
|
||
|
|
|
||
|
|
if not isinstance(exc, astroid.ClassDef):
|
||
|
|
continue
|
||
|
|
|
||
|
|
exc_ancestors = [anc for anc in exc.ancestors()
|
||
|
|
if isinstance(anc, astroid.ClassDef)]
|
||
|
|
|
||
|
|
for prev_part, prev_exc in handled_in_clause:
|
||
|
|
prev_exc_ancestors = [anc for anc in prev_exc.ancestors()
|
||
|
|
if isinstance(anc, astroid.ClassDef)]
|
||
|
|
if exc == prev_exc:
|
||
|
|
self.add_message('overlapping-except',
|
||
|
|
node=handler.type,
|
||
|
|
args='%s and %s are the same' %
|
||
|
|
(prev_part.as_string(),
|
||
|
|
part.as_string()))
|
||
|
|
elif (prev_exc in exc_ancestors or
|
||
|
|
exc in prev_exc_ancestors):
|
||
|
|
ancestor = part if exc in prev_exc_ancestors else prev_part
|
||
|
|
descendant = part if prev_exc in exc_ancestors else prev_part
|
||
|
|
self.add_message('overlapping-except',
|
||
|
|
node=handler.type,
|
||
|
|
args='%s is an ancestor class of %s' %
|
||
|
|
(ancestor.as_string(), descendant.as_string()))
|
||
|
|
handled_in_clause += [(part, exc)]
|
||
|
|
|
||
|
|
|
||
|
|
def register(linter):
|
||
|
|
"""Required method to auto register this checker."""
|
||
|
|
linter.register_checker(OverlappingExceptionsChecker(linter))
|