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

echo "[extensions]" >> $HGRCPATH
echo "fetch=" >> $HGRCPATH

hg init a
echo a > a/a
hg --cwd a commit -d '1 0' -Ama

hg clone a b
hg clone a c

echo b > a/b
hg --cwd a commit -d '2 0' -Amb
hg --cwd a parents -q

echo % should pull one change
hg --cwd b fetch ../a
hg --cwd b parents -q

echo c > c/c
hg --cwd c commit -d '3 0' -Amc
hg --cwd c fetch -d '4 0' -m 'automated merge' ../a
ls c