[FIX] fix the decorator "@wraps" to work on python < 2.5

lp bug: https://launchpad.net/bugs/313547 fixed

bzr revid: christophe@tinyerp.com-20090105115608-ke3du6rq5hvre0pd

bin/tools/func.py

@@ -1,7 +1,7 @@
 # -*- encoding: utf-8 -*-
 ##############################################################################
 #
-#    OpenERP, Open Source Management Solution	
+#    OpenERP, Open Source Management Solution
 #    Copyright (C) 2004-2009 Tiny SPRL (<http://tiny.be>). All Rights Reserved
 #    $Id$
 #
@@ -20,12 +20,60 @@
 #
 ##############################################################################
 
+__all__ = ['partial', 'wraps', 'update_wrapper']
+
 try:
-	from functools import wraps
+    from functools import partial, wraps, update_wrapper
 except ImportError:
-	# this module doesn't exist in python < 2.5
-	# we define a identity decorator
-	def wraps(f):
-		def identity(x):
-			return x
-		return identity
+    # The functools module doesn't exist in python < 2.5
+    # Code taken from python 2.5 
+    # http://svn.python.org/view/python/tags/r254/Lib/functools.py?view=markup
+
+    def partial(fun, *args, **kwargs):
+        def _partial(*args2, **kwargs2):
+            return fun(*(args+args2), **dict(kwargs, **kwargs2))
+        return _partial
+
+    ### --- code from python 2.5
+
+    # update_wrapper() and wraps() are tools to help write
+    # wrapper functions that can handle naive introspection
+
+    WRAPPER_ASSIGNMENTS = ('__module__', '__name__', '__doc__')
+    WRAPPER_UPDATES = ('__dict__',)
+    def update_wrapper(wrapper,
+                       wrapped,
+                       assigned = WRAPPER_ASSIGNMENTS,
+                       updated = WRAPPER_UPDATES):
+        """Update a wrapper function to look like the wrapped function
+
+           wrapper is the function to be updated
+           wrapped is the original function
+           assigned is a tuple naming the attributes assigned directly
+           from the wrapped function to the wrapper function (defaults to
+           functools.WRAPPER_ASSIGNMENTS)
+           updated is a tuple naming the attributes off the wrapper that
+           are updated with the corresponding attribute from the wrapped
+           function (defaults to functools.WRAPPER_UPDATES)
+        """
+        for attr in assigned:
+            setattr(wrapper, attr, getattr(wrapped, attr))
+        for attr in updated:
+            getattr(wrapper, attr).update(getattr(wrapped, attr, {}))
+        # Return the wrapper so this can be used as a decorator via partial()
+        return wrapper
+
+    def wraps(wrapped,
+              assigned = WRAPPER_ASSIGNMENTS,
+              updated = WRAPPER_UPDATES):
+        """Decorator factory to apply update_wrapper() to a wrapper function
+
+           Returns a decorator that invokes update_wrapper() with the decorated
+           function as the wrapper argument and the arguments to wraps() as the
+           remaining arguments. Default arguments are as for update_wrapper().
+           This is a convenience function to simplify applying partial() to
+           update_wrapper().
+        """
+        return partial(update_wrapper, wrapped=wrapped,
+                       assigned=assigned, updated=updated)
+