revset: special case commonancestors(none()) to be empty set
This matches the behavior of ancestor(none()).
From an implementation perspective, ancestor() and commonancestors() are
intersection, and ancestors() is union, so it would make some sense that
commonancestors(none()) returned all revisions. However, ancestor(none())
isn't implemented as such, which breaks ancestor(x) == max(commonancestors(x)).
From a user perspective, ancestors of nothing is nothing whichever type
of operation the ancestor predicate does.
==========
hgignore
==========
---------------------------------
syntax for Mercurial ignore files
---------------------------------
:Author: Vadim Gelfer <vadim.gelfer@gmail.com>
:Organization: Mercurial
:Manual section: 5
:Manual group: Mercurial Manual
.. include:: hgignore.5.gendoc.txt
Author
======
Vadim Gelfer <vadim.gelfer@gmail.com>
Mercurial was written by Matt Mackall <mpm@selenic.com>.
See Also
========
|hg(1)|_, |hgrc(5)|_
Copying
=======
This manual page is copyright 2006 Vadim Gelfer.
Mercurial is copyright 2005-2018 Matt Mackall.
Free use of this software is granted under the terms of the GNU General
Public License version 2 or any later version.
.. include:: common.txt