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

hg init a
cd a
echo bar > foo
hg add foo
hg ci -m 'add foo' -d '1000000 0'

echo foobar > foo
hg ci -m 'change foo' -d '1000001 0'

echo 'quiet:'
hg --quiet diff -r 0 -r 1
echo

echo 'normal:'
hg diff -r 0 -r 1
echo

echo 'verbose:'
hg --verbose diff -r 0 -r 1
echo

echo 'debug:'
hg --debug diff -r 0 -r 1
echo