Files (and subclasses) override __eq__ but not __ne__

[xtian <xtian@…>]

We were trying to compare two model objects using the following function:

def allModelFieldsEqual(a, b):
    fields = [f.name for f in a._meta.fields]
    for name in fields:
        if getattr(a, name) != getattr(b, name):
            return False
    return True

This fails when the models contain FileFields, because File doesn't implement ne. Confusingly, because it implements eq, the values also compare equal.

(Pdb) !a.largeImage
<ImageFieldFile: /images/first-large-image.png>
(Pdb) !b.largeImage
<ImageFieldFile: /images/first-large-image.png>
(Pdb) !a.largeImage == b.largeImage
True
(Pdb) !a.largeImage != b.largeImage
True

It should probably be implemented as:

    def __ne__(self, other):
        return not self == other

[Malcolm Tredinnick]

Fixed in r9647.

[Malcolm Tredinnick]

(In [9648]) [1.0.X] Fixed #9786 -- Fixed inequality checking for django.db.models.fields.file.FieldFile class.

Backport of r9647 from trunk.