Mercurial > hg
diff mercurial/copies.py @ 8527:f9a80054dd3c
use 'x is None' instead of 'x == None'
The built-in None object is a singleton and it is therefore safe to
compare memory addresses with is. It is also faster, how much depends
on the object being compared. For a simple type like str I get:
| s = "foo" | s = None
----------+-----------+----------
s == None | 0.25 usec | 0.21 usec
s is None | 0.17 usec | 0.17 usec
author | Martin Geisler <mg@lazybytes.net> |
---|---|
date | Wed, 20 May 2009 00:52:46 +0200 |
parents | b35d11d10646 |
children | 3f56055ff1d7 431462bd8478 |
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--- a/mercurial/copies.py Wed May 20 00:43:23 2009 +0200 +++ b/mercurial/copies.py Wed May 20 00:52:46 2009 +0200 @@ -106,7 +106,7 @@ return {}, {} # avoid silly behavior for parent -> working dir - if c2.node() == None and c1.node() == repo.dirstate.parents()[0]: + if c2.node() is None and c1.node() == repo.dirstate.parents()[0]: return repo.dirstate.copies(), {} limit = _findlimit(repo, c1.rev(), c2.rev())