tests/test-rename-dir-merge

Add symlink method to util.opener.

Differences from os.symlink:

- the symlink name is relative to the opener base directory

- if a file with that name already exists, it's removed

- if necessary, parent directories are created

- if the system (OS or filesystem) doesn't support symlinks, a
  regular file is created.  Its contents are the symlink target.

#!/bin/sh

mkdir t
cd t
hg init

mkdir a
echo foo > a/a
echo bar > a/b

hg add a
hg ci -m "0" -d "0 0"

hg co -C 0
hg mv a b
hg ci -m "1 mv a/ b/" -d "0 0"

hg co -C 0
echo baz > a/c
hg add a/c
hg ci -m "2 add a/c" -d "0 0"

hg merge --debug 1
echo a/* b/*
hg st -C
hg ci -m "3 merge 2+1" -d "0 0"

hg co -C 1
hg merge --debug 2
echo a/* b/*
hg st -C
hg ci -m "4 merge 1+2" -d "0 0"