From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sat, 23 Jul 2005 19:15:11 +0000 (+0000)
Subject: (no commit message)
X-Git-Tag: rel_0_1_0~850
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=45245eefc212fd14a3505ba68cbf84624154cd00;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

---

diff --git a/lib/sqlalchemy/mapper.py b/lib/sqlalchemy/mapper.py
index 7122418cc3..8f274bd511 100644
--- a/lib/sqlalchemy/mapper.py
+++ b/lib/sqlalchemy/mapper.py
@@ -59,10 +59,10 @@ def globalidentity():
     return _global_identitymap
     
 def eagerload(name):
-    return EagerOption(name)
+    return EagerLazySwitcher(name, toeager = True)
     
 def lazyload(name):
-    return LazyOption(name)
+    return EagerLazySwitcher(name, toeager = False)
 
 class Mapper(object):
     def __init__(self, class_, selectable, table = None, properties = None, identitymap = None, use_smart_properties = True, isroot = True, echo = None):
@@ -253,24 +253,31 @@ class Mapper(object):
 class MapperOption:
     def process(self, mapper):
         raise NotImplementedError()
-        
+
 class MapperProperty:
+    """an element attached to a Mapper that describes the loading and population
+    of an attribute on an object instance."""
     def execute(self, instance, row, identitykey, localmap, isduplicate):
         """called when the mapper receives a row.  instance is the parent instance corresponding
         to the row. """
         raise NotImplementedError()
+
     def setup(self, key, primarytable, statement, **options):
         """called when a statement is being constructed.  """
         return self
+
     def init(self, key, parent, root):
         """called when the MapperProperty is first attached to a new parent Mapper."""
         pass
+    
     def save(self, object, traverse, refetch):
         pass
+    
     def delete(self, object):
         pass
-        
+
 class ColumnProperty(MapperProperty):
+    """describes an object attribute that corresponds to the value in a result set column."""
     def __init__(self, column):
         self.column = column
 
@@ -282,7 +289,7 @@ class ColumnProperty(MapperProperty):
                 setattr(parent.class_, key, SmartProperty(key).property())
         else:
             self.use_smart = False
-            
+
     def execute(self, instance, row, identitykey, localmap, isduplicate):
         if not isduplicate:
             if self.use_smart:
@@ -402,24 +409,20 @@ class EagerLoader(PropertyLoader):
 
         self.mapper._instance(row, localmap, list)
 
-class EagerOption(MapperOption):
+class EagerLazySwitcher(MapperOption):
     """an option that switches a PropertyLoader to be an EagerLoader"""
-    def __init__(self, key):
+    def __init__(self, key, toeager = True):
         self.key = key
+        self.toeager = toeager
 
     def process(self, mapper):
         oldprop = mapper.props[self.key]
-        mapper.set_property(self.key, EagerLoader(oldprop.mapper, oldprop.secondary, primaryjoin = oldprop.primaryjoin, secondaryjoin = oldprop.secondaryjoin))
-        
-class LazyOption(MapperOption):
-    """an option that switches a PropertyLoader to be a LazyLoader"""
-    def __init__(self, key):
-        self.key = key
+        if self.toeager:
+            class_ = EagerLoader
+        else:
+            class_ = LazyLoader
+        mapper.set_property(self.key, class_(oldprop.mapper, oldprop.secondary, primaryjoin = oldprop.primaryjoin, secondaryjoin = oldprop.secondaryjoin))
 
-    def process(self, mapper):
-        oldprop = mapper.props[self.key]
-        mapper.set_property(self.key, LazyLoader(oldprop.mapper, oldprop.whereclause))
-        
 class Aliasizer(sql.ClauseVisitor):
     def __init__(self, table, aliasname):
         self.table = table
diff --git a/test/mapper.py b/test/mapper.py
index 12d9048d94..b710cc1b77 100644
--- a/test/mapper.py
+++ b/test/mapper.py
@@ -143,13 +143,21 @@ class MapperTest(PersistTest):
         l = m.select(users.c.user_name.endswith('ed'))
         print repr(l)
 
-    def testoptions(self):
+    def testeageroptions(self):
         """tests that a lazy relation can be upgraded to an eager relation via the options method"""
         m = mapper(User, users, properties = dict(
             addresses = relation(Address, addresses, lazy = True)
         ), echo = True)
         l = m.options(eagerload('addresses')).select()
         print repr(l)
+
+    def testlazyoptions(self):
+        """tests that an eager relation can be upgraded to a lazy relation via the options method"""
+        m = mapper(User, users, properties = dict(
+            addresses = relation(Address, addresses, lazy = False)
+        ), echo = True)
+        l = m.options(lazyload('addresses')).select()
+        print repr(l)
     
 class LazyTest(PersistTest):
     def setUp(self):