Fixed #7913 -- Corrected backwards incompatible parts of [7977] when optgroup handling was added to field choices (Ticket #4412). Thanks to Michael Elsdorfer (miracle2k) for the report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8102 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/fields/__init__.py

@@ -288,7 +288,7 @@ class Field(object):
         if self.choices:
             field_objs = [oldforms.SelectField]
 
-            params['choices'] = self.flatchoices
+            params['choices'] = self.get_flatchoices()
         else:
             field_objs = self.get_manipulator_field_objs()
         return (field_objs, params)
@@ -362,7 +362,8 @@ class Field(object):
         return val
 
     def get_choices(self, include_blank=True, blank_choice=BLANK_CHOICE_DASH):
-        "Returns a list of tuples used as SelectField choices for this field."
+        """Returns choices with a default blank choices included, for use
+        as SelectField choices for this field."""
         first_choice = include_blank and blank_choice or []
         if self.choices:
             return first_choice + list(self.choices)
@@ -376,6 +377,11 @@ class Field(object):
     def get_choices_default(self):
         return self.get_choices()
 
+    def get_flatchoices(self, include_blank=True, blank_choice=BLANK_CHOICE_DASH):
+        "Returns flattened choices with a default blank choice included."
+        first_choice = include_blank and blank_choice or []
+        return first_choices + list(self.flatchoices)
+
     def _get_val_from_obj(self, obj):
         if obj:
             return getattr(obj, self.attname)
@@ -408,8 +414,9 @@ class Field(object):
     choices = property(_get_choices)
 
     def _get_flatchoices(self):
+        """Flattened version of choices tuple."""
         flat = []
-        for choice, value in self.get_choices_default():
+        for choice, value in self.choices:
             if type(value) in (list, tuple):
                 flat.extend(value)
             else:

tests/modeltests/choices/models.py

@@ -36,4 +36,15 @@ __test__ = {'API_TESTS':"""
 u'Male'
 >>> s.get_gender_display()
 u'Female'
+
+# If the value for the field doesn't correspond to a valid choice,
+# the value itself is provided as a display value.
+>>> a.gender = ''
+>>> a.get_gender_display()
+u''
+
+>>> a.gender = 'U'
+>>> a.get_gender_display()
+u'U'
+
 """}

tests/regressiontests/model_fields/models.py

@@ -11,6 +11,22 @@ class Bar(models.Model):
     b = models.CharField(max_length=10)
     a = models.ForeignKey(Foo, default=get_foo)
 
+class Whiz(models.Model):
+    CHOICES = (
+        ('Group 1', (
+                (1,'First'),
+                (2,'Second'),
+            )
+        ),
+        ('Group 2', (
+                (3,'Third'),
+                (4,'Fourth'),
+            )
+        ),        
+        (0,'Other'),
+    )
+    c = models.IntegerField(choices=CHOICES, null=True)
+    
 __test__ = {'API_TESTS':"""
 # Create a couple of Places.
 >>> f = Foo.objects.create(a='abc')
@@ -21,4 +37,39 @@ __test__ = {'API_TESTS':"""
 <Foo: Foo object>
 >>> b.save()
 
+# Regression tests for #7913
+# Check that get_choices and get_flatchoices interact with
+# get_FIELD_display to return the expected values.
+
+# Test a nested value
+>>> w = Whiz(c=1)
+>>> w.save()
+>>> w.get_c_display()
+u'First'
+
+# Test a top level value
+>>> w.c = 0
+>>> w.save()
+>>> w.get_c_display()
+u'Other'
+
+# Test an invalid data value
+>>> w.c = 9
+>>> w.save()
+>>> w.get_c_display()
+9
+
+# Test a blank data value
+>>> w.c = None
+>>> w.save()
+>>> print w.get_c_display()
+None
+
+# Test an empty data value
+>>> w.c = ''
+>>> w.save()
+>>> w.get_c_display()
+u''
+
+
 """}