Fixed #12215: Added len to ModelChoiceIterator. Thanks Alex and Tobias.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@11850 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/forms/models.py

@@ -910,6 +910,9 @@ class ModelChoiceIterator(object):
             for obj in self.queryset.all():
                 yield self.choice(obj)
 
+    def __len__(self):
+        return len(self.queryset)
+
     def choice(self, obj):
         if self.field.to_field_name:
             key = obj.serializable_value(self.field.to_field_name)

tests/regressiontests/model_forms_regress/tests.py

@@ -101,3 +101,15 @@ class CustomFieldSaveTests(TestCase):
         # generate an AssertionError if it is called more than once during save.
         form = CFFForm(data = {'f': None})
         form.save()
+
+class ModelChoiceIteratorTests(TestCase):
+    def test_len(self):
+        class Form(forms.ModelForm):
+            class Meta:
+                model = Article
+                fields = ["publications"]
+        
+        Publication.objects.create(title="Pravda",
+            date_published=date(1991, 8, 22))
+        f = Form()
+        self.assertEqual(len(f.fields["publications"].choices), 1)