[PATCH 2 of 6 RFC] scmutil": add altvfs class

[Matt Mackall]

On Wed, 2014-12-24 at 13:05 +0100, Angel Ezquerra wrote:
> # HG changeset patch
> # User Angel Ezquerra <angel.ezquerra at gmail.com>
> # Date 1413194278 -7200
> #      Mon Oct 13 11:57:58 2014 +0200
> # Node ID 1664b472cc83f97257c7914c59bfa1600dc64f1a
> # Parent  b213f4439d5427cfff6c7fa28927c25e4422a948
> scmutil": add altvfs class
> 
> The altvfs class is derived from the regular vfs class. It lets you specify an
> alternate base path (altbase) that will be used instead of the regular base path
> when working with a list of "alternate paths" (altpaths).

This is going to complicate things when we get to the next step in the
VFS roadmap where we choose between two classes to use.

http://mercurial.selenic.com/wiki/WindowsUTF8Plan

So I think we want to instead have something like a wrapper class that
takes two VFS objects and presents a union.

-- 
Mathematics is the supreme nostalgia of our time.