def _check_open_encoding(self, node):
"""Check that an open() call always has an encoding set."""
try:
mode_arg = utils.get_argument_from_call(node, position=1,
keyword='mode')
except utils.NoSuchArgumentError:
mode_arg = None
_encoding = None
try:
_encoding = utils.get_argument_from_call(node, position=2)
except utils.NoSuchArgumentError:
try:
_encoding = utils.get_argument_from_call(node,
keyword='encoding')
except utils.NoSuchArgumentError:
pass
if _encoding is None:
if mode_arg is not None:
mode = utils.safe_infer(mode_arg)
if (mode_arg is not None and isinstance(mode, astroid.Const) and
'b' in getattr(mode, 'value', '')):
# Files opened as binary don't need an encoding.
return
else:
self.add_message('open-without-encoding', node=node)
def _check_config(self, node):
"""Check that the arguments to config.get(...) are valid.
FIXME: We should check all ConfigManager calls.
https://github.com/The-Compiler/qutebrowser/issues/107
"""
try:
sect_arg = utils.get_argument_from_call(node, position=0, keyword="sectname")
opt_arg = utils.get_argument_from_call(node, position=1, keyword="optname")
except utils.NoSuchArgumentError:
return
sect_arg = utils.safe_infer(sect_arg)
opt_arg = utils.safe_infer(opt_arg)
if not (isinstance(sect_arg, astroid.Const) and isinstance(opt_arg, astroid.Const)):
return
try:
configdata.DATA[sect_arg.value][opt_arg.value]
except KeyError:
self.add_message("bad-config-call", node=node, args=(sect_arg.value, opt_arg.value))
def _check_config(self, node):
"""Check that the arguments to config.get(...) are valid."""
try:
sect_arg = utils.get_argument_from_call(node, position=0,
keyword='sectname')
opt_arg = utils.get_argument_from_call(node, position=1,
keyword='optname')
except utils.NoSuchArgumentError:
return
sect_arg = utils.safe_infer(sect_arg)
opt_arg = utils.safe_infer(opt_arg)
if not (isinstance(sect_arg, astroid.Const) and
isinstance(opt_arg, astroid.Const)):
return
try:
configdata.DATA[sect_arg.value][opt_arg.value]
except KeyError:
self.add_message('bad-config-call', node=node,
args=(sect_arg.value, opt_arg.value))
def _check_open_mode(self, node):
"""Check that the mode argument of an open or file call is valid."""
try:
mode_arg = utils.get_argument_from_call(node, position=1, keyword="mode")
except utils.NoSuchArgumentError:
return
if mode_arg:
mode_arg = utils.safe_infer(mode_arg)
if isinstance(mode_arg, astroid.Const) and not _check_mode_str(mode_arg.value):
self.add_message("bad-open-mode", node=node, args=mode_arg.value)
def _check_open_mode(self, node):
"""Check that the mode argument of an open or file call is valid."""
try:
mode_arg = utils.get_argument_from_call(node, position=1, keyword='mode')
if mode_arg:
mode_arg = utils.safe_infer(mode_arg)
if (isinstance(mode_arg, astroid.Const)
and not re.match(_VALID_OPEN_MODE_REGEX, mode_arg.value)):
self.add_message('W1501', node=node, args=(mode_arg.value))
except (utils.NoSuchArgumentError, TypeError):
pass
def _check_reversed(self, node):
""" check that the argument to `reversed` is a sequence """
try:
argument = safe_infer(get_argument_from_call(node, position=0))
except NoSuchArgumentError:
self.add_message('missing-reversed-argument', node=node)
else:
if argument is astroid.YES:
return
if argument is None:
# nothing was infered
# try to see if we have iter()
if isinstance(node.args[0], astroid.CallFunc):
try:
func = node.args[0].func.infer().next()
except InferenceError:
return
if (getattr(func, 'name', None) == 'iter' and
is_builtin_object(func)):
self.add_message('bad-reversed-sequence', node=node)
return
if isinstance(argument, astroid.Instance):
if (argument._proxied.name == 'dict' and
is_builtin_object(argument._proxied)):
self.add_message('bad-reversed-sequence', node=node)
return
elif any(ancestor.name == 'dict' and is_builtin_object(ancestor)
for ancestor in argument._proxied.ancestors()):
# mappings aren't accepted by reversed()
self.add_message('bad-reversed-sequence', node=node)
return
for methods in REVERSED_METHODS:
for meth in methods:
try:
argument.getattr(meth)
except astroid.NotFoundError:
break
else:
break
else:
# check if it is a .deque. It doesn't seem that
# we can retrieve special methods
# from C implemented constructs
if argument._proxied.qname().endswith(".deque"):
return
self.add_message('bad-reversed-sequence', node=node)
elif not isinstance(argument, (astroid.List, astroid.Tuple)):
# everything else is not a proper sequence for reversed()
self.add_message('bad-reversed-sequence', node=node)
def testGetArgumentFromCall():
node = astroid.extract_node("foo(a, not_this_one=1, this_one=2)")
arg = utils.get_argument_from_call(node, position=2, keyword="this_one")
assert 2 == arg.value
node = astroid.extract_node("foo(a)")
with pytest.raises(utils.NoSuchArgumentError):
utils.get_argument_from_call(node, position=1)
with pytest.raises(ValueError):
utils.get_argument_from_call(node, None, None)
name = utils.get_argument_from_call(node, position=0)
assert name.name == "a"
def testGetArgumentFromCallExists(fn, kw):
node = astroid.extract_node(fn)
assert utils.get_argument_from_call(node, **kw) is not None
def testGetArgumentFromCallError(fn, kw):
with pytest.raises(utils.NoSuchArgumentError):
node = astroid.extract_node(fn)
utils.get_argument_from_call(node, **kw)
def testGetArgumentFromCallExists(fn, kw):
node = astroid.extract_node(fn)
assert utils.get_argument_from_call(node, **kw) is not None
def _check_new_format_specifiers(self, node, fields, named):
"""
Check attribute and index access in the format
string ("{0.a}" and "{0[a]}").
"""
for key, specifiers in fields:
# Obtain the argument. If it can't be obtained
# or inferred, skip this check.
if key == "":
# {[0]} will have an unnamed argument, defaulting
# to 0. It will not be present in `named`, so use the value
# 0 for it.
key = 0
if isinstance(key, numbers.Number):
try:
argname = utils.get_argument_from_call(node, key)
except utils.NoSuchArgumentError:
continue
else:
if key not in named:
continue
argname = named[key]
if argname in (astroid.Uninferable, None):
continue
try:
argument = utils.safe_infer(argname)
except astroid.InferenceError:
continue
if not specifiers or not argument:
# No need to check this key if it doesn't
# use attribute / item access
continue
if argument.parent and isinstance(argument.parent,
astroid.Arguments):
# Ignore any object coming from an argument,
# because we can't infer its value properly.
continue
previous = argument
parsed = []
for is_attribute, specifier in specifiers:
if previous is astroid.Uninferable:
break
parsed.append((is_attribute, specifier))
if is_attribute:
try:
previous = previous.getattr(specifier)[0]
except astroid.NotFoundError:
if (hasattr(previous, "has_dynamic_getattr")
and previous.has_dynamic_getattr()):
# Don't warn if the object has a custom __getattr__
break
path = get_access_path(key, parsed)
self.add_message(
"missing-format-attribute",
args=(specifier, path),
node=node,
)
break
else:
warn_error = False
if hasattr(previous, "getitem"):
try:
previous = previous.getitem(
astroid.Const(specifier))
except (
astroid.AstroidIndexError,
astroid.AstroidTypeError,
astroid.AttributeInferenceError,
):
warn_error = True
except astroid.InferenceError:
break
if previous is astroid.Uninferable:
break
else:
try:
# Lookup __getitem__ in the current node,
# but skip further checks, because we can't
# retrieve the looked object
previous.getattr("__getitem__")
break
except astroid.NotFoundError:
warn_error = True
if warn_error:
path = get_access_path(key, parsed)
self.add_message("invalid-format-index",
args=(specifier, path),
node=node)
break
try:
previous = next(previous.infer())
except astroid.InferenceError:
# can't check further if we can't infer it
break
def testGetArgumentFromCall(self):
node = test_utils.extract_node('foo(bar=3)')
self.assertIsNotNone(utils.get_argument_from_call(node, keyword='bar'))
with self.assertRaises(utils.NoSuchArgumentError):
node = test_utils.extract_node('foo(3)')
utils.get_argument_from_call(node, keyword='bar')
with self.assertRaises(utils.NoSuchArgumentError):
node = test_utils.extract_node('foo(one=a, two=b, three=c)')
utils.get_argument_from_call(node, position=1)
node = test_utils.extract_node('foo(a, b, c)')
self.assertIsNotNone(utils.get_argument_from_call(node, position=1))
node = test_utils.extract_node('foo(a, not_this_one=1, this_one=2)')
arg = utils.get_argument_from_call(node,
position=2,
keyword='this_one')
self.assertEqual(2, arg.value)
node = test_utils.extract_node('foo(a)')
with self.assertRaises(utils.NoSuchArgumentError):
utils.get_argument_from_call(node, position=1)
with self.assertRaises(ValueError):
utils.get_argument_from_call(node, None, None)
name = utils.get_argument_from_call(node, position=0)
self.assertEqual(name.name, 'a')
def _check_shallow_copy_environ(self, node):
arg = utils.get_argument_from_call(node, position=0)
for inferred in arg.inferred():
if inferred.qname() == OS_ENVIRON:
self.add_message("shallow-copy-environ", node=node)
break
def _check_new_format_specifiers(self, node, fields, named):
"""
Check attribute and index access in the format
string ("{0.a}" and "{0[a]}").
"""
for key, specifiers in fields:
# Obtain the argument. If it can't be obtained
# or infered, skip this check.
if key == '':
# {[0]} will have an unnamed argument, defaulting
# to 0. It will not be present in `named`, so use the value
# 0 for it.
key = 0
if isinstance(key, numbers.Number):
try:
argname = utils.get_argument_from_call(node, key)
except utils.NoSuchArgumentError:
continue
else:
if key not in named:
continue
argname = named[key]
if argname in (astroid.YES, None):
continue
try:
argument = argname.infer().next()
except astroid.InferenceError:
continue
if not specifiers or argument is astroid.YES:
# No need to check this key if it doesn't
# use attribute / item access
continue
if argument.parent and isinstance(argument.parent, astroid.Arguments):
# Check to see if our argument is kwarg or vararg,
# and skip the check for this argument if so, because when inferring,
# astroid will return empty objects (dicts and tuples) and
# that can lead to false positives.
if argname.name in (argument.parent.kwarg, argument.parent.vararg):
continue
previous = argument
parsed = []
for is_attribute, specifier in specifiers:
if previous is astroid.YES:
break
parsed.append((is_attribute, specifier))
if is_attribute:
try:
previous = previous.getattr(specifier)[0]
except astroid.NotFoundError:
if (hasattr(previous, 'has_dynamic_getattr') and
previous.has_dynamic_getattr()):
# Don't warn if the object has a custom __getattr__
break
path = get_access_path(key, parsed)
self.add_message('missing-format-attribute',
args=(specifier, path),
node=node)
break
else:
warn_error = False
if hasattr(previous, 'getitem'):
try:
previous = previous.getitem(specifier)
except (IndexError, TypeError):
warn_error = True
else:
try:
# Lookup __getitem__ in the current node,
# but skip further checks, because we can't
# retrieve the looked object
previous.getattr('__getitem__')
break
except astroid.NotFoundError:
warn_error = True
if warn_error:
path = get_access_path(key, parsed)
self.add_message('invalid-format-index',
args=(specifier, path),
node=node)
break
try:
previous = previous.infer().next()
except astroid.InferenceError:
# can't check further if we can't infer it
break
def testGetArgumentFromCallExists(
fn: str, kw: Union[Dict[str, int], Dict[str, str]]) -> None:
node = astroid.extract_node(fn)
assert utils.get_argument_from_call(node, **kw) is not None
def testGetArgumentFromCall(self):
node = test_utils.extract_node('foo(bar=3)')
self.assertIsNotNone(utils.get_argument_from_call(node, keyword='bar'))
with self.assertRaises(utils.NoSuchArgumentError):
node = test_utils.extract_node('foo(3)')
utils.get_argument_from_call(node, keyword='bar')
with self.assertRaises(utils.NoSuchArgumentError):
node = test_utils.extract_node('foo(one=a, two=b, three=c)')
utils.get_argument_from_call(node, position=1)
node = test_utils.extract_node('foo(a, b, c)')
self.assertIsNotNone(utils.get_argument_from_call(node, position=1))
node = test_utils.extract_node('foo(a, not_this_one=1, this_one=2)')
arg = utils.get_argument_from_call(node, position=1, keyword='this_one')
self.assertEqual(2, arg.value)
node = test_utils.extract_node('foo(a)')
with self.assertRaises(utils.NoSuchArgumentError):
utils.get_argument_from_call(node, position=1)
with self.assertRaises(ValueError):
utils.get_argument_from_call(node, None, None)
name = utils.get_argument_from_call(node, position=0)
self.assertEqual(name.name, 'a')
def _check_new_format_specifiers(self, node, fields, named):
"""
Check attribute and index access in the format
string ("{0.a}" and "{0[a]}").
"""
for key, specifiers in fields:
# Obtain the argument. If it can't be obtained
# or infered, skip this check.
if key == "":
# {[0]} will have an unnamed argument, defaulting
# to 0. It will not be present in `named`, so use the value
# 0 for it.
key = 0
if isinstance(key, numbers.Number):
try:
argname = utils.get_argument_from_call(node, key)
except utils.NoSuchArgumentError:
continue
else:
if key not in named:
continue
argname = named[key]
if argname in (astroid.Uninferable, None):
continue
try:
argument = next(argname.infer())
except astroid.InferenceError:
continue
if not specifiers or argument is astroid.Uninferable:
# No need to check this key if it doesn't
# use attribute / item access
continue
if argument.parent and isinstance(argument.parent, astroid.Arguments):
# Ignore any object coming from an argument,
# because we can't infer its value properly.
continue
previous = argument
parsed = []
for is_attribute, specifier in specifiers:
if previous is astroid.Uninferable:
break
parsed.append((is_attribute, specifier))
if is_attribute:
try:
previous = previous.getattr(specifier)[0]
except astroid.NotFoundError:
if (
hasattr(previous, "has_dynamic_getattr")
and previous.has_dynamic_getattr()
):
# Don't warn if the object has a custom __getattr__
break
path = get_access_path(key, parsed)
self.add_message(
"missing-format-attribute",
args=(specifier, path),
node=node,
)
break
else:
warn_error = False
if hasattr(previous, "getitem"):
try:
previous = previous.getitem(astroid.Const(specifier))
except (
astroid.AstroidIndexError,
astroid.AstroidTypeError,
astroid.AttributeInferenceError,
):
warn_error = True
except astroid.InferenceError:
break
if previous is astroid.Uninferable:
break
else:
try:
# Lookup __getitem__ in the current node,
# but skip further checks, because we can't
# retrieve the looked object
previous.getattr("__getitem__")
break
except astroid.NotFoundError:
warn_error = True
if warn_error:
path = get_access_path(key, parsed)
self.add_message(
"invalid-format-index", args=(specifier, path), node=node
)
break
try:
previous = next(previous.infer())
except astroid.InferenceError:
# can't check further if we can't infer it
break
def _check_new_format_specifiers(self, node, fields, named):
"""
Check attribute and index access in the format
string ("{0.a}" and "{0[a]}").
"""
for key, specifiers in fields:
# Obtain the argument. If it can't be obtained
# or infered, skip this check.
if key == '':
# {[0]} will have an unnamed argument, defaulting
# to 0. It will not be present in `named`, so use the value
# 0 for it.
key = 0
if isinstance(key, numbers.Number):
try:
argname = utils.get_argument_from_call(node, key)
except utils.NoSuchArgumentError:
continue
else:
if key not in named:
continue
argname = named[key]
if argname in (astroid.YES, None):
continue
try:
argument = argname.infer().next()
except astroid.InferenceError:
continue
if not specifiers or argument is astroid.YES:
# No need to check this key if it doesn't
# use attribute / item access
continue
if argument.parent and isinstance(argument.parent,
astroid.Arguments):
# Check to see if our argument is kwarg or vararg,
# and skip the check for this argument if so, because when inferring,
# astroid will return empty objects (dicts and tuples) and
# that can lead to false positives.
if argname.name in (argument.parent.kwarg,
argument.parent.vararg):
continue
previous = argument
parsed = []
for is_attribute, specifier in specifiers:
if previous is astroid.YES:
break
parsed.append((is_attribute, specifier))
if is_attribute:
try:
previous = previous.getattr(specifier)[0]
except astroid.NotFoundError:
if (hasattr(previous, 'has_dynamic_getattr')
and previous.has_dynamic_getattr()):
# Don't warn if the object has a custom __getattr__
break
path = get_access_path(key, parsed)
self.add_message('missing-format-attribute',
args=(specifier, path),
node=node)
break
else:
warn_error = False
if hasattr(previous, 'getitem'):
try:
previous = previous.getitem(specifier)
except (IndexError, TypeError):
warn_error = True
else:
try:
# Lookup __getitem__ in the current node,
# but skip further checks, because we can't
# retrieve the looked object
previous.getattr('__getitem__')
break
except astroid.NotFoundError:
warn_error = True
if warn_error:
path = get_access_path(key, parsed)
self.add_message('invalid-format-index',
args=(specifier, path),
node=node)
break
try:
previous = previous.infer().next()
except astroid.InferenceError:
# can't check further if we can't infer it
break
def _check_shallow_copy_environ(self, node):
arg = utils.get_argument_from_call(node, position=0)
for inferred in arg.inferred():
if inferred.qname() == OS_ENVIRON:
self.add_message('shallow-copy-environ', node=node)
break
def includes_exc_info(node):
try:
exc_info = utils.get_argument_from_call(node, keyword='exc_info')
except utils.NoSuchArgumentError:
return False
return bool(exc_info.value)
def _check_use_maxsplit_arg(self, node: astroid.Call) -> None:
"""Add message when accessing first or last elements of a str.split() or str.rsplit()."""
# Check if call is split() or rsplit()
if not (isinstance(node.func, astroid.Attribute)
and node.func.attrname in ("split", "rsplit") and isinstance(
utils.safe_infer(node.func), astroid.BoundMethod)):
return
try:
utils.get_argument_from_call(node, 0, "sep")
except utils.NoSuchArgumentError:
return
try:
# Ignore if maxsplit arg has been set
utils.get_argument_from_call(node, 1, "maxsplit")
return
except utils.NoSuchArgumentError:
pass
if isinstance(node.parent, astroid.Subscript):
try:
subscript_value = utils.get_subscript_const_value(
node.parent).value
except utils.InferredTypeError:
return
# Check for cases where variable (Name) subscripts may be mutated within a loop
if isinstance(node.parent.slice, astroid.Name):
# Check if loop present within the scope of the node
scope = node.scope()
for loop_node in scope.nodes_of_class(
(astroid.For, astroid.While)):
loop_node = cast(astroid.node_classes.NodeNG, loop_node)
if not loop_node.parent_of(node):
continue
# Check if var is mutated within loop (Assign/AugAssign)
for assignment_node in loop_node.nodes_of_class(
astroid.AugAssign):
assignment_node = cast(astroid.AugAssign,
assignment_node)
if node.parent.slice.name == assignment_node.target.name:
return
for assignment_node in loop_node.nodes_of_class(
astroid.Assign):
assignment_node = cast(astroid.Assign, assignment_node)
if node.parent.slice.name in [
n.name for n in assignment_node.targets
]:
return
if subscript_value in (-1, 0):
fn_name = node.func.attrname
new_fn = "rsplit" if subscript_value == -1 else "split"
new_name = (
node.func.as_string().rsplit(fn_name, maxsplit=1)[0] +
new_fn +
f"({node.args[0].as_string()}, maxsplit=1)[{subscript_value}]"
)
self.add_message("use-maxsplit-arg",
node=node,
args=(new_name, ))
def testGetArgumentFromCallError(fn, kw):
with pytest.raises(utils.NoSuchArgumentError):
node = astroid.extract_node(fn)
utils.get_argument_from_call(node, **kw)
def testGetArgumentFromCallError(
fn: str, kw: Union[Dict[str, int], Dict[str, str]]) -> None:
with pytest.raises(utils.NoSuchArgumentError):
node = astroid.extract_node(fn)
utils.get_argument_from_call(node, **kw)
