Although Python supports `X = Y if COND else Z`, this was only
introduced in Python 2.5. Since we have to support Python 2.4, it was
a very common thing to write instead `X = COND and Y or Z`, which is a
bit obscure at a glance. It requires some intricate knowledge of
Python to understand how to parse these one-liners.
We change instead all of these one-liners to 4-liners. This was
executed with the following perlism:
find -name "*.py" -exec perl -pi -e 's,(\s*)([\.\w]+) = \(?(\S+)\s+and\s+(\S*)\)?\s+or\s+(\S*)$,$1if $3:\n$1 $2 = $4\n$1else:\n$1 $2 = $5,' {} \;
I tweaked the following cases from the automatic Perl output:
prev = (parents and parents[0]) or nullid
port = (use_ssl and 443 or 80)
cwd = (pats and repo.getcwd()) or ''
rename = fctx and webutil.renamelink(fctx) or []
ctx = fctx and fctx or ctx
self.base = (mapfile and os.path.dirname(mapfile)) or ''
I also added some newlines wherever they seemd appropriate for readability
There are probably a few ersatz ternary operators still in the code
somewhere, lurking away from the power of a simple regex.
Adds a new discovery method based on repeatedly sampling the still
undecided subset of the local node graph to determine the set of nodes
common to both the client and the server.
For small differences between client and server, it uses about the same
or slightly fewer roundtrips than the old tree-based discovery. For
larger differences, it typically reduces the number of roundtrips
drastically (from 150 to 4, for instance).
The old discovery code now lives in treediscovery.py, the new code is
in setdiscovery.py.
Still missing is a hook for extensions to contribute nodes to the
initial sample. For instance, Augie's remotebranches could contribute
the last known state of the server's heads.
Credits for the actual sampler and computing common heads instead of
bases go to Benoit Boissinot.