--- a/mercurial/patch.py	Sun Jan 03 18:16:42 2010 +0100
+++ b/mercurial/patch.py	Sun Jan 03 20:36:30 2010 +0100
@@ -1166,6 +1166,8 @@
     finally:
         if cwd:
             os.chdir(curdir)
+        if fp != patchobj:
+            fp.close()
     if ret < 0:
         raise PatchError
     return ret > 0