Merge branch 'master' of https://github.com/MeirKriheli/mongoengine

Conflicts:
	docs/changelog.rst

AUTHORS

@@ -105,4 +105,5 @@ that much better:
  * Adam Reeve
  * Anthony Nemitz
  * deignacio
- * shaunduncan
+ * shaunduncan
+ * Meir Kriheli

docs/changelog.rst

@@ -4,6 +4,7 @@ Changelog
 
 Changes in 0.6.X
 ================
+- Added PULL reverse_delete_rule
 - Fixed CASCADE delete bug
 - Fixed db_field data load error
 - Fixed recursive save with FileField

docs/guide/defining-documents.rst

@@ -289,6 +289,10 @@ Its value can take any of the following constants:
 :const:`mongoengine.CASCADE`
   Any object containing fields that are refererring to the object being deleted
   are deleted first.
+:const:`mongoengine.PULL`
+  Removes the reference to the object (using MongoDB's "pull" operation)
+  from any object's fields of
+  :class:`~mongoengine.ListField` (:class:`~mongoengine.ReferenceField`).
 
 
 .. warning::

mongoengine/fields.py

@@ -656,6 +656,7 @@ class ReferenceField(BaseField):
       * NULLIFY     - Updates the reference to null.
       * CASCADE     - Deletes the documents associated with the reference.
       * DENY        - Prevent the deletion of the reference object.
+      * PULL        - Pull the reference from a :class:`~mongoengine.ListField` of references
 
     Alternative syntax for registering delete rules (useful when implementing
     bi-directional delete rules)

mongoengine/queryset.py

@@ -10,7 +10,7 @@ from bson.code import Code
 from mongoengine import signals
 
 __all__ = ['queryset_manager', 'Q', 'InvalidQueryError',
-           'DO_NOTHING', 'NULLIFY', 'CASCADE', 'DENY']
+           'DO_NOTHING', 'NULLIFY', 'CASCADE', 'DENY', 'PULL']
 
 
 # The maximum number of items to display in a QuerySet.__repr__
@@ -21,6 +21,7 @@ DO_NOTHING = 0
 NULLIFY = 1
 CASCADE = 2
 DENY = 3
+PULL = 4
 
 
 class DoesNotExist(Exception):
@@ -1321,6 +1322,10 @@ class QuerySet(object):
                 document_cls.objects(**{field_name + '__in': self}).update(
                         safe_update=safe,
                         **{'unset__%s' % field_name: 1})
+            elif rule == PULL:
+                document_cls.objects(**{field_name + '__in': self}).update(
+                        safe_update=safe,
+                        **{'pull_all__%s' % field_name: self})
 
         self._collection.remove(self._query, safe=safe)
 

tests/test_queryset.py

@@ -1419,6 +1419,36 @@ class QuerySetTest(unittest.TestCase):
 
         self.assertRaises(OperationError, self.Person.objects.delete)
 
+    def test_reverse_delete_rule_pull(self):
+        """Ensure pulling of references to deleted documents.
+        """
+        class BlogPost(Document):
+            content = StringField()
+            authors = ListField(ReferenceField(self.Person,
+                reverse_delete_rule=PULL))
+
+        BlogPost.drop_collection()
+        self.Person.drop_collection()
+
+        me = self.Person(name='Test User')
+        me.save()
+
+        someoneelse = self.Person(name='Some-one Else')
+        someoneelse.save()
+
+        post = BlogPost(content='Watching TV', authors=[me, someoneelse])
+        post.save()
+
+        another = BlogPost(content='Chilling Out', authors=[someoneelse])
+        another.save()
+
+        someoneelse.delete()
+        post.reload()
+        another.reload()
+
+        self.assertEqual(post.authors, [me])
+        self.assertEqual(another.authors, [])
+
     def test_update(self):
         """Ensure that atomic updates work properly.
         """