Add dirstate.pathto and localrepo.pathto. Every time util.pathto is called, we have to pass the repo root and the repo cwd. dirstate.pathto is a simple convenience function that knows about the root and the cwd arguments. It's still possible to pass the cwd as an optimization. localrepo.pathto is a convenience function that just calls dirstate.pathto, just like localrepo.getcwd. dirstate.pathto becomes a single point that converts most (all?) paths from the internal representation to some OS-specific relative path for display purposes.

#!/bin/sh

hg init
echo a > a
hg commit -A -ma

echo a >> a
hg commit -mb

echo a >> a
hg commit -mc

hg up 1
echo a >> a
hg commit -md

hg up 1
echo a >> a
hg commit -me

hg up 1
echo % should fail because not at a head
hg merge

hg up
echo % should fail because \> 2 heads
hg merge

echo % should succeed
hg merge 2
hg commit -mm1

echo % should succeed - 2 heads
hg merge
hg commit -mm2

echo % should fail because 1 head
hg merge

true