changelog: lazily parse description
Before, the description field was converted to a localstr at parse
time. With this patch, we store the raw description and convert to
a localstr when it is first accessed.
We see a revset speedup for revsets that don't access the description:
author(mpm)
0.896565
0.914234
0.869085
date(2015)
0.878797
0.891980
0.862525
extra(rebase_source)
0.865446
0.912514
0.871500
author(mpm) or author(greg)
1.801832
1.860402
1.791589
date(2015) or branch(default)
0.968276
0.994673
0.974027
author(mpm) or desc(bug) or date(2015) or extra(rebase_source)
3.656193
3.721032
3.643593
As you can see, most of these revsets are already faster than from
before this refactoring: we have already offset the performance
loss from the introduction of the new class representing parsed
changelog entries!
#require serve
$ hg init test
$ cd test
$ cat > .hg/hgrc <<EOF
> [extensions]
> # this is only necessary to check that the mapping from
> # interhg to websub works
> interhg =
>
> [websub]
> issues = s|Issue(\d+)|<a href="http://bts.example.org/issue\1">Issue\1</a>|
>
> [interhg]
> # check that we maintain some interhg backwards compatibility...
> # yes, 'x' is a weird delimiter...
> markbugs = sxbugx<i class="\x">bug</i>x
> EOF
$ touch foo
$ hg add foo
$ hg commit -d '1 0' -m 'Issue123: fixed the bug!'
$ hg serve -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
$ cat hg.pid >> $DAEMON_PIDS
log
$ get-with-headers.py localhost:$HGPORT "rev/tip" | grep bts
<div class="description"><a href="http://bts.example.org/issue123">Issue123</a>: fixed the <i class="x">bug</i>!</div>
errors
$ cat errors.log
$ cd ..