workingfilectx: always use the same filelog, even for renames
workingfilectx() was using the "src" filelog in case the file was renamed in
the working copy.
For consistency, stop special-casing it. This allows us to remove some
duplication between filectx and workingfilectx.
Martin Geisler <mg@lazybytes.net> [Wed, 20 May 2009 00:52:46 +0200] rev 8527
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