Do not depend on a CPython implementation detail anymore...

...to make Roundup more compatible with other Python implementation
like PyPy.

Closes issue2550707. Thanks to Christof Meerwald.

Author: Bernhard Reiter

CHANGES.txt

@@ -7,6 +7,9 @@ Entries without name were done by Richard Jones.
 
 Fixed:
 
+- Do not depend on a CPython implementation detail anymore to make Roundup 
+  more compatible with other Python implementation like PyPy.
+  Closes issue2550707. Thanks to Christof Meerwald. (Bernhard Reiter)
 - Yet another fix to the mail gateway, messages got *all* files of
   an issue, not just the new ones. Thanks to Rafal Bisingier for
   reporting and proposing a fix. The regression test was updated.

roundup/instance.py

@@ -30,6 +30,7 @@
 
 import os
 import sys
+import __builtin__
 from roundup import configuration, mailgw
 from roundup import hyperdb, backends, actions
 from roundup.cgi import client, templating
@@ -86,7 +87,7 @@ def __init__(self, tracker_home, optimize=0):
                 sys.path.remove(libdir)
 
     def get_backend_name(self):
-        o = __builtins__['open']
+        o = __builtin__.open
         f = o(os.path.join(self.config.DATABASE, 'backend_name'))
         name = f.readline().strip()
         f.close()