Set serialize=False on TaggableManager to fix tagged object serializing

taggit/managers.py

@@ -73,7 +73,7 @@ class ExtraJoinRestriction(object):
 class TaggableManager(RelatedField, Field):
     def __init__(self, verbose_name=_("Tags"),
         help_text=_("A comma-separated list of tags."), through=None, blank=False):
-        Field.__init__(self, verbose_name=verbose_name, help_text=help_text, blank=blank)
+        Field.__init__(self, verbose_name=verbose_name, help_text=help_text, blank=blank, null=True, serialize=False)
         self.through = through or TaggedItem
         self.rel = TaggableRel(self)
 

tests/tests.py

@@ -5,6 +5,7 @@ from unittest import TestCase as UnitTestCase
 import django
 from django.conf import settings
 from django.core.exceptions import ValidationError
+from django.core import serializers
 from django.db import connection
 from django.test import TestCase, TransactionTestCase
 from django.utils import six
@@ -336,6 +337,10 @@ class TaggableManagerTestCase(BaseTaggingTestCase):
         apple.tags.add('red')
         self.assertEqual(list(apple.tags.slugs()), ['green-and-juicy', 'red'])
 
+    def test_serializes(self):
+        apple = self.food_model.objects.create(name="apple")
+        serializers.serialize("json", (apple,))
+
 
 class TaggableManagerDirectTestCase(TaggableManagerTestCase):
     food_model = DirectFood