Default attribute accessor now returns a field default for a field provided by a subtype.

docs/HISTORY.txt

@@ -4,6 +4,10 @@ Changelog
 2.0.1 (unreleased)
 ------------------
 
+- The default attribute accessor now also looks through subtypes
+  (behaviors) to find a field default.
+  [malthe]
+
 - Added support in the FTI to look up behaviors by utility name when
   getting additional schemata (i.e. fields provided by behaviors).
 

plone/dexterity/content.py

@@ -185,7 +185,13 @@ class DexterityContent(DAVResourceMixin, PortalContent, DefaultDublinCoreImpl, C
             field = schema.get(name, None)
             if field is not None:
                 return deepcopy(field.default)
-        
+
+        # do the same for each subtype
+        for schema in SCHEMA_CACHE.subtypes(self.portal_type):
+            field = schema.get(name, None)
+            if field is not None:
+                return deepcopy(field.default)
+
         raise AttributeError(name)
     
     # Let __name__ and id be identical. Note that id must be ASCII in Zope 2,

plone/dexterity/tests/test_content.py

@@ -231,7 +231,7 @@ class TestContent(MockTestCase):
             pass
         
         class ISubtype(Interface):
-            pass
+            baz = zope.schema.TextLine(title=u"baz", default=u"baz")
         
         behavior1 = BehaviorRegistration(u"Behavior1", "", IBehavior1, None, None)
         behavior2 = BehaviorRegistration(u"Behavior2", "", IBehavior2, ISubtype, None)
@@ -258,7 +258,10 @@ class TestContent(MockTestCase):
         # the cache. This is not the case, as evidenced by .count(1) above.
         self.assertEquals(True, ISubtype.providedBy(item))
         self.assertEquals(True, ISchema.providedBy(item))
-        
+
+        # Subtypes provide field defaults.
+        self.assertEquals(u"baz", getattr(item, "baz", None))
+
         # We also need to ensure that the _v_ attribute doesn't hide any
         # interface set directly on the instance with alsoProvides() or
         # directlyProvides(). This is done by clearing the cache when these