hub/venv/lib/python3.7/site-packages/jedi/inference/analysis.py

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"""
Module for statical analysis.
"""
from parso.python import tree
from jedi._compatibility import force_unicode
from jedi import debug
from jedi.inference.helpers import is_string
CODES = {
'attribute-error': (1, AttributeError, 'Potential AttributeError.'),
'name-error': (2, NameError, 'Potential NameError.'),
'import-error': (3, ImportError, 'Potential ImportError.'),
'type-error-too-many-arguments': (4, TypeError, None),
'type-error-too-few-arguments': (5, TypeError, None),
'type-error-keyword-argument': (6, TypeError, None),
'type-error-multiple-values': (7, TypeError, None),
'type-error-star-star': (8, TypeError, None),
'type-error-star': (9, TypeError, None),
'type-error-operation': (10, TypeError, None),
'type-error-not-iterable': (11, TypeError, None),
'type-error-isinstance': (12, TypeError, None),
'type-error-not-subscriptable': (13, TypeError, None),
'value-error-too-many-values': (14, ValueError, None),
'value-error-too-few-values': (15, ValueError, None),
}
class Error(object):
def __init__(self, name, module_path, start_pos, message=None):
self.path = module_path
self._start_pos = start_pos
self.name = name
if message is None:
message = CODES[self.name][2]
self.message = message
@property
def line(self):
return self._start_pos[0]
@property
def column(self):
return self._start_pos[1]
@property
def code(self):
# The class name start
first = self.__class__.__name__[0]
return first + str(CODES[self.name][0])
def __unicode__(self):
return '%s:%s:%s: %s %s' % (self.path, self.line, self.column,
self.code, self.message)
def __str__(self):
return self.__unicode__()
def __eq__(self, other):
return (self.path == other.path and self.name == other.name
and self._start_pos == other._start_pos)
def __ne__(self, other):
return not self.__eq__(other)
def __hash__(self):
return hash((self.path, self._start_pos, self.name))
def __repr__(self):
return '<%s %s: %s@%s,%s>' % (self.__class__.__name__,
self.name, self.path,
self._start_pos[0], self._start_pos[1])
class Warning(Error):
pass
def add(node_context, error_name, node, message=None, typ=Error, payload=None):
exception = CODES[error_name][1]
if _check_for_exception_catch(node_context, node, exception, payload):
return
# TODO this path is probably not right
module_context = node_context.get_root_context()
module_path = module_context.py__file__()
issue_instance = typ(error_name, module_path, node.start_pos, message)
debug.warning(str(issue_instance), format=False)
node_context.inference_state.analysis.append(issue_instance)
return issue_instance
def _check_for_setattr(instance):
"""
Check if there's any setattr method inside an instance. If so, return True.
"""
module = instance.get_root_context()
node = module.tree_node
if node is None:
# If it's a compiled module or doesn't have a tree_node
return False
try:
stmt_names = node.get_used_names()['setattr']
except KeyError:
return False
return any(node.start_pos < n.start_pos < node.end_pos
# Check if it's a function called setattr.
and not (n.parent.type == 'funcdef' and n.parent.name == n)
for n in stmt_names)
def add_attribute_error(name_context, lookup_value, name):
message = ('AttributeError: %s has no attribute %s.' % (lookup_value, name))
# Check for __getattr__/__getattribute__ existance and issue a warning
# instead of an error, if that happens.
typ = Error
if lookup_value.is_instance() and not lookup_value.is_compiled():
# TODO maybe make a warning for __getattr__/__getattribute__
if _check_for_setattr(lookup_value):
typ = Warning
payload = lookup_value, name
add(name_context, 'attribute-error', name, message, typ, payload)
def _check_for_exception_catch(node_context, jedi_name, exception, payload=None):
"""
Checks if a jedi object (e.g. `Statement`) sits inside a try/catch and
doesn't count as an error (if equal to `exception`).
Also checks `hasattr` for AttributeErrors and uses the `payload` to compare
it.
Returns True if the exception was catched.
"""
def check_match(cls, exception):
if not cls.is_class():
return False
for python_cls in exception.mro():
if cls.py__name__() == python_cls.__name__ \
and cls.parent_context.is_builtins_module():
return True
return False
def check_try_for_except(obj, exception):
# Only nodes in try
iterator = iter(obj.children)
for branch_type in iterator:
next(iterator) # The colon
suite = next(iterator)
if branch_type == 'try' \
and not (branch_type.start_pos < jedi_name.start_pos <= suite.end_pos):
return False
for node in obj.get_except_clause_tests():
if node is None:
return True # An exception block that catches everything.
else:
except_classes = node_context.infer_node(node)
for cls in except_classes:
from jedi.inference.value import iterable
if isinstance(cls, iterable.Sequence) and \
cls.array_type == 'tuple':
# multiple exceptions
for lazy_value in cls.py__iter__():
for typ in lazy_value.infer():
if check_match(typ, exception):
return True
else:
if check_match(cls, exception):
return True
def check_hasattr(node, suite):
try:
assert suite.start_pos <= jedi_name.start_pos < suite.end_pos
assert node.type in ('power', 'atom_expr')
base = node.children[0]
assert base.type == 'name' and base.value == 'hasattr'
trailer = node.children[1]
assert trailer.type == 'trailer'
arglist = trailer.children[1]
assert arglist.type == 'arglist'
from jedi.inference.arguments import TreeArguments
args = TreeArguments(node_context.inference_state, node_context, arglist)
unpacked_args = list(args.unpack())
# Arguments should be very simple
assert len(unpacked_args) == 2
# Check name
key, lazy_value = unpacked_args[1]
names = list(lazy_value.infer())
assert len(names) == 1 and is_string(names[0])
assert force_unicode(names[0].get_safe_value()) == payload[1].value
# Check objects
key, lazy_value = unpacked_args[0]
objects = lazy_value.infer()
return payload[0] in objects
except AssertionError:
return False
obj = jedi_name
while obj is not None and not isinstance(obj, (tree.Function, tree.Class)):
if isinstance(obj, tree.Flow):
# try/except catch check
if obj.type == 'try_stmt' and check_try_for_except(obj, exception):
return True
# hasattr check
if exception == AttributeError and obj.type in ('if_stmt', 'while_stmt'):
if check_hasattr(obj.children[1], obj.children[3]):
return True
obj = obj.parent
return False