contrib/hgweb.wsgi

log: make -frREV PATH detect missing files before falling back to slow path

If -rREV isn't specified, "log --follow" would abort on nonexistent paths.
Let's implement this behavior for "-frREV" case as we have ctx.hasdir() now.
Otherwise "log -frREV PATH" would silently fall back to slow path and files
wouldn't be followed across renames.

The loop is quadratic (as before), but the size of the startctxs and
match.files() should be small in general.

Some tests are marked as BROKEN since file renames aren't tracked in the
slow path. This is a known limitation of the current history traversal
function.

# An example WSGI for use with mod_wsgi, edit as necessary
# See https://mercurial-scm.org/wiki/modwsgi for more information

# 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()

# enable demandloading to reduce startup time
from mercurial import demandimport; demandimport.enable()

from mercurial.hgweb import hgweb
application = hgweb(config)