[pypy-commit] pypy default: make str.captitalize not do extra copies.

[alex_gaynor]

Author: Alex Gaynor <alex.gaynor at gmail.com>
Branch: 
Changeset: r47941:c154a210d625
Date: 2011-10-11 12:33 -0400
http://bitbucket.org/pypy/pypy/changeset/c154a210d625/

Log:	make str.captitalize not do extra copies.

diff --git a/pypy/objspace/std/stringobject.py b/pypy/objspace/std/stringobject.py
--- a/pypy/objspace/std/stringobject.py
+++ b/pypy/objspace/std/stringobject.py
@@ -178,24 +178,24 @@
 
 def str_capitalize__String(space, w_self):
     input = w_self._value
-    buffer = [' '] * len(input)
+    builder = StringBuilder(len(input))
     if len(input) > 0:
         ch = input[0]
         if ch.islower():
             o = ord(ch) - 32
-            buffer[0] = chr(o)
+            builder.append(chr(o))
         else:
-            buffer[0] = ch
+            builder.append(ch)
 
         for i in range(1, len(input)):
             ch = input[i]
             if ch.isupper():
                 o = ord(ch) + 32
-                buffer[i] = chr(o)
+                builder.append(chr(o))
             else:
-                buffer[i] = ch
+                builder.append(ch)
 
-    return space.wrap("".join(buffer))
+    return space.wrap(builder.build())
 
 def str_title__String(space, w_self):
     input = w_self._value