Added support for null=True (and default=None) to BitField class.

bitfield/models.py

@@ -57,7 +57,8 @@ def __get__(self, obj, type=None):
         if obj is None:
             return BitFieldFlags(self.field.flags)
         retval = obj.__dict__[self.field.name]
-        if self.field.__class__ is BitField:
+        # handle case where value of field is None
+        if not retval is None and self.field.__class__ is BitField:
             # Update flags from class in case they've changed.
             retval._keys = self.field.flags
         return retval
@@ -106,7 +107,11 @@ def pre_save(self, instance, add):
     def get_prep_value(self, value):
         if isinstance(value, (BitHandler, Bit)):
             value = value.mask
-        return int(value)
+        # handle case where value is None
+        if value is not None:
+            return int(value)
+        else:
+            return value
 
     # def get_db_prep_save(self, value, connection):
     #     if isinstance(value, Bit):
@@ -133,7 +138,10 @@ def get_prep_lookup(self, lookup_type, value):
     def to_python(self, value):
         if isinstance(value, Bit):
             value = value.mask
-        if not isinstance(value, BitHandler):
+        # handle case where value is None
+        if value is None:
+            pass
+        elif not isinstance(value, BitHandler):
             # Regression for #1425: fix bad data that was created resulting
             # in negative values for flags.  Compute the value that would
             # have been visible ot the application to preserve compatibility.

bitfield/tests/models.py

@@ -28,3 +28,10 @@ class CompositeBitFieldTestModel(models.Model):
         'flags_2',
     ))
 
+class BitFieldNullDefaultModel(models.Model):
+    flags = BitField(flags=(
+        'FLAG_0',
+        'FLAG_1',
+        'FLAG_2',
+        'FLAG_3',
+    ), null=True, default=None, db_column='another_default_null_name')

bitfield/tests/tests.py

@@ -3,7 +3,7 @@
 from django.test import TestCase
 
 from bitfield import BitHandler, Bit
-from bitfield.tests import BitFieldTestModel, CompositeBitFieldTestModel
+from bitfield.tests import BitFieldTestModel, CompositeBitFieldTestModel, BitFieldNullDefaultModel
 
 class BitHandlerTest(TestCase):
     def test_defaults(self):
@@ -289,3 +289,31 @@ def test_hasattr(self):
         self.assertEqual(hasattr(inst.flags, 'flag_4'),
             hasattr(inst.flags_2, 'flag_4'))
 
+class NullDefaultBitfieldTest(TestCase):
+    """Null values for bitfields used to not work. This test checks to make sure they do work
+       now and don't break other non-null cases."""
+    def test_create_default_null(self):
+        inst = BitFieldNullDefaultModel()
+        # flags should be None (null) by default
+        self.assertIsNone(inst.flags)
+        inst.save()
+        # make sure still None (null) after save
+        self.assertIsNone(inst.flags)
+        inst = BitFieldNullDefaultModel.objects.get(pk=inst.pk)
+        # make sure still None (null) after being loaded back in
+        self.assertIsNone(inst.flags)
+        # make sure we can still set the flags
+        inst.flags = 1
+        self.assertEqual(type(inst.flags),BitHandler)
+        inst.save()
+        inst = BitFieldNullDefaultModel.objects.get(pk=inst.pk)
+        self.assertEqual(type(inst.flags),BitHandler)
+        self.assertTrue(inst.flags.FLAG_0.is_set)
+        # and that we haven't broken things
+        self.assertFalse(inst.flags.FLAG_1.is_set)
+        inst.save()
+        inst = BitFieldNullDefaultModel.objects.get(pk=inst.pk)
+        self.assertEqual(type(inst.flags),BitHandler)
+        self.assertTrue(inst.flags.FLAG_0.is_set)
+        self.assertFalse(inst.flags.FLAG_1.is_set)
+

setup.py

@@ -4,7 +4,7 @@
 
 setup(
     name='django-bitfield',
-    version='1.5.0',
+    version='1.5.0.ejs',
     author='DISQUS',
     author_email='[email protected]',
     url='http://github.com/disqus/django-bitfield',