in library/inspect.py [0:0]
def classify_class_attrs(cls):
"""Return list of attribute-descriptor tuples.
For each name in dir(cls), the return list contains a 4-tuple
with these elements:
0. The name (a string).
1. The kind of attribute this is, one of these strings:
'class method' created via classmethod()
'static method' created via staticmethod()
'property' created via property()
'method' any other flavor of method or descriptor
'data' not a method
2. The class which defined this attribute (a class).
3. The object as obtained by calling getattr; if this fails, or if the
resulting object does not live anywhere in the class' mro (including
metaclasses) then the object is looked up in the defining class's
dict (found by walking the mro).
If one of the items in dir(cls) is stored in the metaclass it will now
be discovered and not have None be listed as the class in which it was
defined. Any items whose home class cannot be discovered are skipped.
"""
mro = getmro(cls)
metamro = getmro(type(cls)) # for attributes stored in the metaclass
metamro = tuple(cls for cls in metamro if cls not in (type, object))
class_bases = (cls,) + mro
all_bases = class_bases + metamro
names = dir(cls)
# :dd any DynamicClassAttributes to the list of names;
# this may result in duplicate entries if, for example, a virtual
# attribute with the same name as a DynamicClassAttribute exists.
for base in mro:
for k, v in base.__dict__.items():
if isinstance(v, types.DynamicClassAttribute):
names.append(k)
result = []
processed = set()
for name in names:
# Get the object associated with the name, and where it was defined.
# Normal objects will be looked up with both getattr and directly in
# its class' dict (in case getattr fails [bug #1785], and also to look
# for a docstring).
# For DynamicClassAttributes on the second pass we only look in the
# class's dict.
#
# Getting an obj from the __dict__ sometimes reveals more than
# using getattr. Static and class methods are dramatic examples.
homecls = None
get_obj = None
dict_obj = None
if name not in processed:
try:
if name == '__dict__':
raise Exception("__dict__ is special, don't want the proxy")
get_obj = getattr(cls, name)
except Exception as exc:
pass
else:
homecls = getattr(get_obj, "__objclass__", homecls)
if homecls not in class_bases:
# if the resulting object does not live somewhere in the
# mro, drop it and search the mro manually
homecls = None
last_cls = None
# first look in the classes
for srch_cls in class_bases:
srch_obj = getattr(srch_cls, name, None)
if srch_obj is get_obj:
last_cls = srch_cls
# then check the metaclasses
for srch_cls in metamro:
try:
srch_obj = srch_cls.__getattr__(cls, name)
except AttributeError:
continue
if srch_obj is get_obj:
last_cls = srch_cls
if last_cls is not None:
homecls = last_cls
for base in all_bases:
if name in base.__dict__:
dict_obj = base.__dict__[name]
if homecls not in metamro:
homecls = base
break
if homecls is None:
# unable to locate the attribute anywhere, most likely due to
# buggy custom __dir__; discard and move on
continue
obj = get_obj if get_obj is not None else dict_obj
# Classify the object or its descriptor.
if isinstance(dict_obj, (staticmethod, types.BuiltinMethodType)):
kind = "static method"
obj = dict_obj
elif isinstance(dict_obj, (classmethod, types.ClassMethodDescriptorType)):
kind = "class method"
obj = dict_obj
elif isinstance(dict_obj, property):
kind = "property"
obj = dict_obj
elif isroutine(obj):
kind = "method"
else:
kind = "data"
result.append(Attribute(name, kind, homecls, obj))
processed.add(name)
return result