Since assignments on M2M or reverse FK descriptors is composed of a `clear()`,
followed by an `add()`, `clear()` could potentially affect the value of the
assigned queryset before the `add()` step; pre-evaluating it solves the problem.
This patch fixes the issue for ForeignRelatedObjectsDescriptor,
ManyRelatedObjectsDescriptor, and ReverseGenericRelatedObjectsDescriptor.
It completes 6cb6e1 which addressed ReverseManyRelatedObjectsDescriptor.
GenericRelation now supports an optional related_query_name argument.
Setting related_query_name adds a relation from the related object back to
the content type for filtering, ordering and other query operations.
Thanks to Loic Bistuer for spotting a couple of important issues in
his review.
Allows a `GenericForeignKey` to reference proxy models. The default
for `for_concrete_model` is `True` to keep backwards compatibility.
Also added the analog `for_concrete_model` kwarg to
`generic_inlineformset_factory` to provide an API at the form level.
This also updates all dependent functionality, including modelform_factory
and modelformset_factory, and the generic views `ModelFormMixin`,
`CreateView` and `UpdateView` which gain a new `fields` attribute.
Loic Bistuer
Gabe Jackson
Simon Charette
Jason Myers
Alasdair Nicol
Tim Graham
Alasdair Nicol
Bouke Haarsma
Pablo Mouzo
Claude Paroz
Bojan Mihelac
Gavin Wahl
Marc Tamlyn
Anssi Kääriäinen
Luke Plant
Loic Bistuer
Florian Apolloner