Ticket #16663: 16663-failing-test.patch

tests/modeltests/choices/tests.py

@@ -1 +1 @@
 from django.test import TestCase
 
-from models import Person
+from models import Person, Mutant
 
 
 class ChoicesTests(TestCase):
+
     def test_display(self):
         a = Person.objects.create(name='Adrian', gender='M')
         s = Person.objects.create(name='Sara', gender='F')
@@ -21 +22 @@
         a.gender = 'U'
         self.assertEqual(a.get_gender_display(), 'U')
 
+    def test_mutable_list_of_choices(self):
+        # Regression test for #16663: when a list (or list-like object) is
+        # passed in the `choices` keyword argument of the field, it must be
+        # used even if it's empty.
+        m = Mutant.objects.create(name='Alien', gender='O')
+        import pdb; pdb.set_trace()
+        self.assertEqual(m.get_gender_display(), 'O')
+        Mutant.gender_choices = [('O', 'Other')]
+        self.assertEqual(m.get_gender_display(), 'Other')
+        

tests/modeltests/choices/models.py

@@ -22 +22 @@
 
     def __unicode__(self):
         return self.name
+
+
+class Mutant(models.Model):
+    gender_choices = []
+
+    name = models.CharField(max_length=20)
+    gender = models.CharField(max_length=1, choices=gender_choices)

django/db/models/fields/__init__.py

@@ -93 +93 @@
         self.serialize = serialize
         self.unique_for_date, self.unique_for_month = unique_for_date, unique_for_month
         self.unique_for_year = unique_for_year
-        self._choices = choices or []
+        self._choices = [] if choices is None else choices
         self.help_text = help_text
         self.db_column = db_column
         self.db_tablespace = db_tablespace or settings.DEFAULT_INDEX_TABLESPACE