transaction: clarify the "quick abort" scenario
Right now, the transaction has a code-pass to do a "quick abort" that skip most¹
(too much) of the logic when the right condition are detected²
We are about to improve this logic in multiple aspect. We clarify the code
first.
The conditional return in `_can_quick_abort` looks a bit weird because we are
about to make them more complex very soon.
[1] actually too much
[2] actually not often enough
#!/usr/bin/env python3
#
# 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 = b"/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)