Re: [PATCH 3/4] add -u: only show pathless 'add -u' warning when changes exist outside cwd

On Tue, Mar 19, 2013 at 11:25 AM, Junio C Hamano [off-list ref] wrote:

I am wondering if we can special case the no-pathspec case to have
add_files_to_cache() call underlying run_diff_files() without any
pathspec, inspect the paths that are modified and/or deleted in the
update_callback, add ones that are under the $prefix while noticing
the ones outside as warning worthy events.

My concern is run full-tree diff can be expensive on large repos (one
of the reasons the user may choose to work from within a
subdirectory). We can exit as soon as we find a difference outside
$prefix. But in case we find nothing, we need to diff the whole
worktree.
-- 
Duy