diff options
Diffstat (limited to 'checkers/base.py')
| -rw-r--r-- | checkers/base.py | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/checkers/base.py b/checkers/base.py index 604685a..943f65e 100644 --- a/checkers/base.py +++ b/checkers/base.py @@ -676,7 +676,13 @@ functions, methods variable names, max locals """ self.stats[node.is_method() and 'method' or 'function'] += 1 + self._check_dangerous_default(node) + + def _check_dangerous_default(self, node): # check for dangerous default values as arguments + is_iterable = lambda n: isinstance(n, (astroid.List, + astroid.Set, + astroid.Dict)) for default in node.args.defaults: try: value = next(default.infer()) @@ -685,24 +691,30 @@ functions, methods if (isinstance(value, astroid.Instance) and value.qname() in DEFAULT_ARGUMENT_SYMBOLS): - is_infered_builtin = isinstance( - value, - (astroid.List, astroid.Tuple, astroid.Set)) + if value is default: msg = DEFAULT_ARGUMENT_SYMBOLS[value.qname()] - elif type(value) is astroid.Instance or is_infered_builtin: - if isinstance(default, astroid.CallFunc): - # this argument is direct call to list() or dict() etc + elif type(value) is astroid.Instance or is_iterable(value): + # We are here in the following situation(s): + # * a dict/set/list/tuple call which wasn't inferred + # to a syntax node ({}, () etc.). This can happen + # when the arguments are invalid or unknown to + # the inference. + # * a variable from somewhere else, which turns out to be a list + # or a dict. + if is_iterable(default): + msg = value.pytype() + elif isinstance(default, astroid.CallFunc): msg = '%s() (%s)' % (value.name, value.qname()) else: - # this argument is a variable from somewhere else which turns - # out to be a list or dict msg = '%s (%s)' % (default.as_string(), value.qname()) else: # this argument is a name msg = '%s (%s)' % (default.as_string(), DEFAULT_ARGUMENT_SYMBOLS[value.qname()]) - self.add_message('dangerous-default-value', node=node, args=(msg,)) + self.add_message('dangerous-default-value', + node=node, + args=(msg, )) @check_messages('unreachable', 'lost-exception') def visit_return(self, node): |