revset: delay showing parse error for the revset alias until it is referred
Before this patch, a problematic revset alias aborts execution
immediately, even if it isn't referred in the specified revset.
If old "hg" may be used too (for example, bisecting Mercurial itself),
it is also difficult to write alias definitions using features newly
introduced by newer "hg" into configuration files, because such alias
definitions cause unexpected abortion at parsing revset aliases with
old "hg".
This patch delays showing parse error for the revset alias until it is
actually referred at runtime.
This patch detects referring problematic aliases in "_expandaliases"
by examination of "revsetalias.error", which is initialized with the
error message only when parsing fails.
For usability, this patch also warns about problematic aliases, even
if they aren't referred at runtime. This should help users to know
potential problems in their alias definitions earlier.
# An example WSGI for use with mod_wsgi, edit as necessary
# See http://mercurial.selenic.com/wiki/modwsgi for more information
# 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()
# enable demandloading to reduce startup time
from mercurial import demandimport; demandimport.enable()
from mercurial.hgweb import hgweb
application = hgweb(config)