fixed a _get_criterion mismatch, cleaned up types + updated types doc

3 files changed, 20 insertions, 21 deletions

diff --git a/lib/sqlalchemy/mapping/mapper.py b/lib/sqlalchemy/mapping/mapper.py
index 15d197a34..7977cae6a 100644
--- a/lib/sqlalchemy/mapping/mapper.py
+++ b/lib/sqlalchemy/mapping/mapper.py
@@ -450,6 +450,22 @@ class Mapper(object):
             self._options[optkey] = mapper
             return mapper
 
+    def _get_criterion(self, key, value):
+        """used by select_by to match a key/value pair against
+        local properties, column names, or a matching property in this mapper's
+        list of relations."""
+        if self.props.has_key(key):
+            return self.props[key].columns[0] == value
+        elif self.table.c.has_key(key):
+            return self.table.c[key] == value
+        else:
+            for prop in self.props.values():
+                c = prop.get_criterion(key, value)
+                if c is not None:
+                    return c
+            else:
+                return None
+
     def __getattr__(self, key):
         if (key.startswith('select_by_') or key.startswith('get_by_')):
             return getattr(self.query, key)
diff --git a/lib/sqlalchemy/mapping/query.py b/lib/sqlalchemy/mapping/query.py
index 2ef23c560..283e8c189 100644
--- a/lib/sqlalchemy/mapping/query.py
+++ b/lib/sqlalchemy/mapping/query.py
@@ -177,7 +177,7 @@ class Query(object):
         for key, value in params.iteritems():
             if value is False:
                 continue
-            c = self._get_criterion(key, value)
+            c = self.mapper._get_criterion(key, value)
             if c is None:
                 raise InvalidRequestError("Cant find criterion for property '"+ key + "'")
             if clause is None:
@@ -261,18 +261,3 @@ class Query(object):
             value.setup(key, statement, **kwargs) 
         return statement
 
-    def _get_criterion(self, key, value):
-        """used by select_by to match a key/value pair against
-        local properties, column names, or a matching property in this mapper's
-        list of relations."""
-        if self.props.has_key(key):
-            return self.props[key].columns[0] == value
-        elif self.table.c.has_key(key):
-            return self.table.c[key] == value
-        else:
-            for prop in self.props.values():
-                c = prop.get_criterion(key, value)
-                if c is not None:
-                    return c
-            else:
-                return None
diff --git a/lib/sqlalchemy/types.py b/lib/sqlalchemy/types.py
index 40b94bbd8..bc894184f 100644
--- a/lib/sqlalchemy/types.py
+++ b/lib/sqlalchemy/types.py
@@ -67,7 +67,9 @@ class TypeDecorator(AbstractType):
     def convert_result_value(self, value, engine):
         return self.impl.convert_result_value(value, engine)
     def copy(self):
-        raise NotImplementedError()
+        instance = self.__class__.__new__(self.__class__)
+        instance.__dict__.update(self.__dict__)
+        return instance
         
 def to_instance(typeobj):
     if typeobj is None:
@@ -132,8 +134,6 @@ class Unicode(TypeDecorator):
              return value.decode(engine.encoding)
          else:
              return value
-    def copy(self):
-        return Unicode(self.impl.length)
         
 class Integer(TypeEngine):
     """integer datatype"""
@@ -194,8 +194,6 @@ class PickleType(TypeDecorator):
       if value is None:
           return None
       return self.impl.convert_bind_param(pickle.dumps(value, self.protocol), engine)
-    def copy(self):
-        return PickleType(self.protocol)
 
 class Boolean(TypeEngine):
     pass