Failing iterable check on types

[rpkilby]

Hi. The iterable check on Line 25 doesn't work when encountering types.

pysize/pysize.py

Line 25 in e94d25c

elif hasattr(obj, '__iter__') and not isinstance(obj, (str, bytes, bytearray)):

I believe this should be changed to

    elif isinstance(obj, collections.Iterable) and not isinstance(obj, (str, bytes, bytearray)):

[bosswissam]

@rpkilby can you provide an example of the failure?

[bosswissam]

@rpkilby Hi. I will change this algorithm to use a recursive approach. For now if you are blocked you can use sys.setrecursionlimit. Good catch!

[rpkilby]

Yep

>>> from collections import OrderedDict
>>> from pysize import get_size
>>> get_size(OrderedDict)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/bagel/Documents/django-rest-framework-filters/pysize.py", line 26, in get_size
    size += sum((get_size(i, seen) for i in obj))
TypeError: 'type' object is not iterable

[rpkilby]

@bosswissam - it's not a recursion issue, just a simple TypeError. I've fixed it locally by making the change in my original comment.

[rpkilby]

Basically, OrderedDict.__iter__ exists as an unbound method, but the OrderedDict type is not itself iterable, which is why the preceding check erroneously passes.

Hope that helps.

[bosswissam]

@rpkilby Apologies I seem to have had another issues open and left a comment on this one mistakenly. Yup will make this change, also feel free to send a PR if you'd like.

[kelechifletcher]

Please correct me if I'm wrong, but if a TypeError is occurring simply because a type object has been encountered, wouldn't adding type to the isinstance classinfo tuple fix this issue?

elif hasattr(obj, '__iter__') and not isinstance(obj, (type, str, bytes, bytearray)):