[1.1.X] Fixed #11940 - ModelForm evaluates callable default values on form class creation

Thanks to Harm Geerts for the report and initial patch.

Backport of [12721] from trunk


git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12722 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/fields/__init__.py

@@ -322,9 +322,11 @@ class Field(object):
         "Returns a django.forms.Field instance for this database Field."
         defaults = {'required': not self.blank, 'label': capfirst(self.verbose_name), 'help_text': self.help_text}
         if self.has_default():
-            defaults['initial'] = self.get_default()
             if callable(self.default):
+                defaults['initial'] = self.default
                 defaults['show_hidden_initial'] = True
+            else:
+                defaults['initial'] = self.get_default()
         if self.choices:
             # Fields with choices get special treatment.
             include_blank = self.blank or not (self.has_default() or 'initial' in kwargs)

tests/modeltests/model_formsets/models.py

@@ -930,7 +930,7 @@ False
 # when determine what extra forms have changed to save.
 
 >>> form = formset.forms[0] # this formset only has one form
->>> now = form.fields['date_joined'].initial
+>>> now = form.fields['date_joined'].initial()
 >>> print form.as_p()
 <p><label for="id_membership_set-0-date_joined">Date joined:</label> <input type="text" name="membership_set-0-date_joined" value="..." id="id_membership_set-0-date_joined" /><input type="hidden" name="initial-membership_set-0-date_joined" value="..." id="initial-membership_set-0-id_membership_set-0-date_joined" /></p>
 <p><label for="id_membership_set-0-karma">Karma:</label> <input type="text" name="membership_set-0-karma" id="id_membership_set-0-karma" /><input type="hidden" name="membership_set-0-person" value="1" id="id_membership_set-0-person" /><input type="hidden" name="membership_set-0-id" id="id_membership_set-0-id" /></p>

tests/regressiontests/forms/models.py

@@ -15,10 +15,17 @@ temp_storage = FileSystemStorage(location=temp_storage_location)
 class BoundaryModel(models.Model):
     positive_integer = models.PositiveIntegerField(null=True, blank=True)
 
+callable_default_value = 0
+def callable_default():
+    global callable_default_value
+    callable_default_value = callable_default_value + 1
+    return callable_default_value
+
 class Defaults(models.Model):
     name = models.CharField(max_length=255, default='class default value')
     def_date = models.DateField(default = datetime.date(1980, 1, 1))
     value = models.IntegerField(default=42)
+    callable_default = models.IntegerField(default=callable_default)
 
 class ChoiceModel(models.Model):
     """For ModelChoiceField and ModelMultipleChoiceField tests."""
@@ -85,6 +92,10 @@ u'class default value'
 datetime.date(1980, 1, 1)
 >>> DefaultsForm().fields['value'].initial
 42
+>>> r1 = DefaultsForm()['callable_default'].as_widget()
+>>> r2 = DefaultsForm()['callable_default'].as_widget()
+>>> r1 == r2
+False
 
 In a ModelForm that is passed an instance, the initial values come from the
 instance's values, not the model's defaults.
@@ -102,7 +113,7 @@ datetime.date(1969, 4, 4)
 ...     name = CharField(max_length=255)
 ...     class Meta:
 ...         model = Defaults
-...         exclude = ['name']
+...         exclude = ['name', 'callable_default']
 >>> f = ExcludingForm({'name': u'Hello', 'value': 99, 'def_date': datetime.date(1999, 3, 2)})
 >>> f.is_valid()
 True