hgweb.cgi

commit: clear resolved mergestate even if working copy is clean

If the mergestate has resolved conflicts and a commit is successfully
created (either because there are changes in the working copy or
because ui.allowemptycommit=yes), we will also clear the merge
state. However, if the working copy is clean (and
ui.allowemptycommit=no), we leave the mergestate there. The user may
notice it in `hg resolve -l` output (but not in `hg status -v`
output). It's not clear how the user should clear it, but probably via
`hg co -C .`. It's also quite likely that they won't even notice it
and it will get cleared by a later `hg commit` (of unrelated
changes).

This patch makes it so that `hg commit` also clears resolved merge
conflicts even if the command doesn't end up writing a commit because
the working copy was empty. That's probably a little weird (commands
that abort should generally avoid changing the repo), but it still
seems mostly harmless, and it reduces the risk of more bugs like
https://bz.mercurial-scm.org/show_bug.cgi?id=5494. I just ran into a
version of that bug in the Evolve extension and that's what triggered
this series.

Differential Revision: https://phab.mercurial-scm.org/D8196

#!/usr/bin/env python
#
# An example hgweb CGI script, edit as necessary
# See also https://mercurial-scm.org/wiki/PublishingRepositories

# Path to repo or hgweb config to serve (see 'hg help hgweb')
config = "/path/to/repo/or/config"

# Uncomment and adjust if Mercurial is not installed system-wide
# (consult "installed modules" path from 'hg debuginstall'):
# import sys; sys.path.insert(0, "/path/to/python/lib")

# Uncomment to send python tracebacks to the browser if an error occurs:
# import cgitb; cgitb.enable()

from mercurial import demandimport

demandimport.enable()
from mercurial.hgweb import hgweb, wsgicgi

application = hgweb(config)
wsgicgi.launch(application)