[PATCH 1 of 2] context: fix repo[n] not to make invalid changectx if n is out of range

[Yuya Nishihara]

On Mon, 02 Feb 2015 14:25:54 +0000, Pierre-Yves David wrote:
> On 02/02/2015 02:15 PM, Yuya Nishihara wrote:
> > # HG changeset patch
> > # User Yuya Nishihara <yuya at tcha.org>
> > # Date 1420883783 -32400
> > #      Sat Jan 10 18:56:23 2015 +0900
> > # Node ID 184aa519a7a72ab10361d91f66455e3cea8f4f50
> > # Parent  3667bc21b8773715d9472a3b4e034b77e62c6451
> > context: fix repo[n] not to make invalid changectx if n is out of range
> >
> > This problem was spotted by ba89f7b542c9 (and eb763217152a), so it uses
> > fullreposet(repo) instead. This fix is necessary to rewrite "rev()" revset
> > without using fullreposet.
> >
> > diff --git a/mercurial/context.py b/mercurial/context.py
> > --- a/mercurial/context.py
> > +++ b/mercurial/context.py
> > @@ -371,6 +371,8 @@ class changectx(basectx):
> >
> >           try:
> >               if isinstance(changeid, int):
> > +                if changeid < nullrev or changeid >= len(repo.changelog):
> 
> len(repo.changelog) can be more expensive than you expect this is has to 
> take filtering into account (iirc),

I think it just returns revlog.__len__(), and changectx.__init__() does it
for string revision.

> you probably want `changeid in repo.changelog`

It will iterate all nodes in changelog, see eb763217152a.

Regards,