Back out [8120] for a bit. Refs #6217. It's having unintended side-effects (a.k.a breaks the tree)

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8126 bcc190cf-cafb-0310-a4f2-bffc1f526a37

3 files changed, 22 insertions, 33 deletions

diff --git a/AUTHORS b/AUTHORS
index cf03e891ec..26b2e0540f 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -407,7 +407,6 @@ answer newbie questions, and generally made Django that much better:
     charly.wilhelm@gmail.com
     Rachel Willmer <http://www.willmer.com/kb/>
     Gary Wilson <gary.wilson@gmail.com>
-    Jakub Wilk <ubanus@users.sf.net>
     Jakub Wiśniowski <restless.being@gmail.com>
     Maciej Wiśniowski <pigletto@gmail.com>
     wojtek
diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index edd7ba257f..dd5117fb78 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -191,8 +191,7 @@ class Field(object):
     def set_attributes_from_name(self, name):
         self.name = name
         self.attname, self.column = self.get_attname_column()
-        if self.verbose_name is None and name:
-            self.verbose_name = name.replace('_', ' ')
+        self.verbose_name = self.verbose_name or (name and name.replace('_', ' '))
 
     def contribute_to_class(self, cls, name):
         self.set_attributes_from_name(name)
diff --git a/django/utils/functional.py b/django/utils/functional.py
index e465ab5fec..3de693e18c 100644
--- a/django/utils/functional.py
+++ b/django/utils/functional.py
@@ -148,51 +148,42 @@ def lazy(func, *resultclasses):
     function is evaluated on every access.
     """
     class __proxy__(Promise):
-        """
-        Encapsulate a function call and act as a proxy for methods that are
-        called on the result of that function. The function is not evaluated
-        until one of the methods on the result is called.
-        """
-        __dispatch = None
-
+        # This inner class encapsulates the code that should be evaluated
+        # lazily. On calling of one of the magic methods it will force
+        # the evaluation and store the result. Afterwards, the result
+        # is delivered directly. So the result is memoized.
         def __init__(self, args, kw):
             self.__func = func
             self.__args = args
             self.__kw = kw
-            if self.__dispatch is None:
-                self.__prepare_class__()
-
-        def __prepare_class__(cls):
-            cls.__dispatch = {}
+            self.__dispatch = {}
             for resultclass in resultclasses:
-                cls.__dispatch[resultclass] = {}
+                self.__dispatch[resultclass] = {}
                 for (k, v) in resultclass.__dict__.items():
-                    if hasattr(cls, k):
-                        continue
-                    setattr(cls, k, cls.__promise__(resultclass, k, v))
-            cls._delegate_str = str in resultclasses
-            cls._delegate_unicode = unicode in resultclasses
-            assert not (cls._delegate_str and cls._delegate_unicode), "Cannot call lazy() with both str and unicode return types."
-            if cls._delegate_unicode:
-                cls.__unicode__ = cls.__unicode_cast
-            elif cls._delegate_str:
-                cls.__str__ = cls.__str_cast
-        __prepare_class__ = classmethod(__prepare_class__)
+                    setattr(self, k, self.__promise__(resultclass, k, v))
+            self._delegate_str = str in resultclasses
+            self._delegate_unicode = unicode in resultclasses
+            assert not (self._delegate_str and self._delegate_unicode), "Cannot call lazy() with both str and unicode return types."
+            if self._delegate_unicode:
+                # Each call to lazy() makes a new __proxy__ object, so this
+                # doesn't interfere with any other lazy() results.
+                __proxy__.__unicode__ = __proxy__.__unicode_cast
+            elif self._delegate_str:
+                __proxy__.__str__ = __proxy__.__str_cast
 
-        def __promise__(cls, klass, funcname, func):
+        def __promise__(self, klass, funcname, func):
             # Builds a wrapper around some magic method and registers that magic
             # method for the given type and method name.
-            def __wrapper__(self, *args, **kw):
+            def __wrapper__(*args, **kw):
                 # Automatically triggers the evaluation of a lazy value and
                 # applies the given magic method of the result type.
                 res = self.__func(*self.__args, **self.__kw)
                 return self.__dispatch[type(res)][funcname](res, *args, **kw)
 
-            if klass not in cls.__dispatch:
-                cls.__dispatch[klass] = {}
-            cls.__dispatch[klass][funcname] = func
+            if klass not in self.__dispatch:
+                self.__dispatch[klass] = {}
+            self.__dispatch[klass][funcname] = func
             return __wrapper__
-        __promise__ = classmethod(__promise__)
 
         def __unicode_cast(self):
             return self.__func(*self.__args, **self.__kw)