ManyToOneRel.name uses relatemodelname instead of relatedmodelname_set

[Maxim Syabro]

F.e.

class MainModel(models.Model):
pass

class RelatedModel(models.Model):
main = models.ForeignKey(MainModel)

ManyToOneRel.name should be relatedmodel_set, not
relatedmodel

>>> from testmodels.models import MainModel
>>> fieldname = MainModel._meta.get_fields()[0].name
>>> print getattr(MainModel, fieldname, None)
None
>>> print getattr(MainModel, fieldname + '_set', None)
object at 0x103dc1510>}}}

[Tim Graham]

I'm not sure if the proposal is correct. You can use get_accessor_name() to retrieve relatedmodel_set. If you provide a patch that shows how to fix this as your propose and doesn't break any tests, that might confirm whether or not the idea is correct.

[Tim Graham]

The relevant attribute is ​ForeignObjectRel.name which is an alias for related_query_name().

[Maxim Syabro]

Tim, what if someone will have this situation:

class MainModel(models.Model):
    relatedmodel = IntegerField()

class RelatedModel(models.Model):
    main = models.ForeignKey(MainModel)

Turns out ReverseManyToOneDescriptor will replace original field. So I think it's ambiguous a little bit. Don't you think?

from .models import MainModel
for i, field in enumerate(MainModel._meta.get_fields()):
    fieldname = field.name
    print i, fieldname
    print getattr(MainModel, fieldname, None)
    print getattr(MainModel, fieldname + '_set', None)
    print

will give this output

0 relatedmodel
None
<django.db.models.fields.related_descriptors.ReverseManyToOneDescriptor object at 0x1076db950>

1 id
None
None

2 relatedmodel
None
<django.db.models.fields.related_descriptors.ReverseManyToOneDescriptor object at 0x1076db950>

[Maxim Syabro]

Okay, I missed this error

ERRORS:
testmodels.RelatedModel.main: (fields.E303) Reverse query name for 'RelatedModel.main' clashes with field name 'MainModel.relatedmodel'.
	HINT: Rename field 'MainModel.relatedmodel', or add/change a related_name argument to the definition for field 'RelatedModel.main'.

And I still have this questions:

1. Why does it clash?
2. Why related model have two names: 'relatedmodel' and 'relatedmodel_set' if we can use only second one?
3. Why name property can't return 'relatedmodel_set' to avoid stuff above?

[Tim Graham]

I can't answer the questions offhand. I'd suggest trying to develop a patch making the change you suggest and then looking at the test failures if you want to understand how Django works.