fancyopts: add early-options parser compatible with getopt()
The next patch will add a flag for strict parsing of early options, where
we'll have to parse all early options at once instead of processing them
one-by-one by dispatch._earlygetopt(). That's why I decided to hook
fancyopts().
All dispatch._early*opt() functions is planned to be replaced with this
function. But in this stable series, only the strict mode will be handled
by fancyopts.earlygetopt().
#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 ..