Commit 53da1e47 authored by Malcolm Tredinnick's avatar Malcolm Tredinnick
Browse files

Fixed #9649 -- Better error handling in model creation. 

Previously, you could explicitly assign None to a non-null ForeignKey
(or other) field when creating the model (Child(parent=None), etc). We
now throw an exception when you do that, which matches the behaviour
when you assign None to the attribute after creation.

Thanks to ales.zoulek@gmail.com and ondrej.kohout@gmail.com for some
analysis of this problem.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@9983 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent b5d4a8ae

django/db/models/base.py

+7 −6
Original line number Diff line number Diff line
@@ -224,12 +224,13 @@ class Model(object): 
        # keywords, or default.



        for field in fields_iter:

            rel_obj = None

            is_related_object = False

            if kwargs:

                if isinstance(field.rel, ManyToOneRel):

                    try:

                        # Assume object instance was passed in.

                        rel_obj = kwargs.pop(field.name)

                        is_related_object = True

                    except KeyError:

                        try:

                            # Object instance wasn't passed in -- must be an ID.
@@ -245,11 +246,11 @@ class Model(object): 
                    val = kwargs.pop(field.attname, field.get_default())

            else:

                val = field.get_default()

            # If we got passed a related instance, set it using the field.name

            # instead of field.attname (e.g. "user" instead of "user_id") so

            # that the object gets properly cached (and type checked) by the

            # RelatedObjectDescriptor.

            if rel_obj:

            if is_related_object:

                # If we are passed a related instance, set it using the

                # field.name instead of field.attname (e.g. "user" instead of

                # "user_id") so that the object gets properly cached (and type

                # checked) by the RelatedObjectDescriptor.

                setattr(self, field.name, rel_obj)

            else:

                setattr(self, field.attname, val)

tests/regressiontests/many_to_one_regress/models.py

+12 −1
Original line number Diff line number Diff line 
"""

Regression tests for a few FK bugs: #1578, #6886

Regression tests for a few ForeignKey bugs.

"""



from django.db import models
@@ -106,6 +106,17 @@ Traceback (most recent call last): 
    ...

ValueError: Cannot assign "<First: First object>": "Child.parent" must be a "Parent" instance.



# Nor can you explicitly assign None to Child.parent during object creation

# (regression for #9649).

>>> Child(name='xyzzy', parent=None)

Traceback (most recent call last):

    ...

ValueError: Cannot assign None: "Child.parent" does not allow null values.

>>> Child.objects.create(name='xyzzy', parent=None)

Traceback (most recent call last):

    ...

ValueError: Cannot assign None: "Child.parent" does not allow null values.



# Creation using keyword argument should cache the related object.

>>> p = Parent.objects.get(name="Parent")

>>> c = Child(parent=p)