From 409a95adf44f577a204114469ff414bebefca293 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Fri, 1 Jul 2011 11:32:07 -0400
Subject: [PATCH]   - Fixed bug in the mutable extension whereby     if None or
 a non-corresponding type were set,     an error would be raised.  None is now
 accepted     which assigns None to all attributes,     illegal values raise
 ValueError.

---
 CHANGES                       |  6 ++++++
 lib/sqlalchemy/ext/mutable.py | 20 ++++++++++----------
 test/ext/test_mutable.py      | 18 ++++++++++++++++++
 3 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/CHANGES b/CHANGES
index 92881a3416..4c2243f9fb 100644
--- a/CHANGES
+++ b/CHANGES
@@ -89,6 +89,12 @@ CHANGES
     mapping, the attributes beyond the first
     would not get instrumented.
 
+  - Fixed bug in the mutable extension whereby
+    if None or a non-corresponding type were set, 
+    an error would be raised.  None is now accepted
+    which assigns None to all attributes,
+    illegal values raise ValueError.
+
 - examples
   - Repaired the examples/versioning test runner
     to not rely upon SQLAlchemy test libs,
diff --git a/lib/sqlalchemy/ext/mutable.py b/lib/sqlalchemy/ext/mutable.py
index b31710ca8b..ece7e3ad48 100644
--- a/lib/sqlalchemy/ext/mutable.py
+++ b/lib/sqlalchemy/ext/mutable.py
@@ -346,6 +346,16 @@ class MutableBase(object):
 
         return weakref.WeakKeyDictionary()
 
+    @classmethod
+    def coerce(cls, key, value):
+        """Given a value, coerce it into this type.
+
+        By default raises ValueError.
+        """
+        if value is None:
+            return None
+        raise ValueError("Attribute '%s' does not accept objects of type %s" % (key, type(value)))
+
     @classmethod
     def _listen_on_attribute(cls, attribute, coerce, parent_cls):
         """Establish this type as a mutation listener for the given 
@@ -423,16 +433,6 @@ class Mutable(MutableBase):
         for parent, key in self._parents.items():
             flag_modified(parent, key)
 
-    @classmethod
-    def coerce(cls, key, value):
-        """Given a value, coerce it into this type.
-
-        By default raises ValueError.
-        """
-        if value is None:
-            return None
-        raise ValueError("Attribute '%s' does not accept objects of type %s" % (key, type(value)))
-
     @classmethod
     def associate_with_attribute(cls, attribute):
         """Establish this type as a mutation listener for the given 
diff --git a/test/ext/test_mutable.py b/test/ext/test_mutable.py
index 9d0a4a0c89..df4006c01b 100644
--- a/test/ext/test_mutable.py
+++ b/test/ext/test_mutable.py
@@ -355,6 +355,24 @@ class MutableCompositesTest(_CompositeTestBase, fixtures.MappedTest):
             f2.data.y = 12
             assert f2 in sess.dirty
 
+    def test_set_none(self):
+        sess = Session()
+        f1 = Foo(data=None)
+        sess.add(f1)
+        sess.commit()
+        eq_(f1.data, Point(None, None))
+
+        f1.data.y = 5
+        sess.commit()
+        eq_(f1.data, Point(None, 5))
+
+    def test_set_illegal(self):
+        f1 = Foo()
+        assert_raises_message(
+            ValueError,
+            "Attribute 'data' does not accept objects",
+            setattr, f1, 'data', 'foo'
+        )
 
 class MutableInheritedCompositesTest(_CompositeTestBase, fixtures.MappedTest):
     @classmethod
-- 
2.39.5