Re: [PATCH 3/3] Mark new entries skip-worktree appropriately

[Jonathan Nieder <jrnieder@gmail.com>]

Nguyễn Thái Ngọc Duy wrote:

> Sparse checkout updates worktree based on the old and new
> skip-worktree status when $GIT_DIR/info/sparse-checkout changes:
> 
> old = ce_skip_worktree(ce);           // current skip-worktree
> new = will_have_skip_work_tree(ce);   // from $GIT..sparse-checkout
> if (old && !new) add_file_back(ce);   // shrink checkout area
> if (!old && new) remove_file_out(ce); [1] // enlarge checkout area
> 
> New entries after merging will always have skip-worktree unset
> (i.e. old = 0). If those files are filtered out by
> $GIT_DIR/info/sparse-checkout (i.e. new != 0), then case [1] will
> happen. But there is nothing to remove because they're new.

When using unpack_trees to add a new file, there is no in-file
index entry to grab the previous skip worktree bit from.  If it
is outside the checkout area, we should pretend it was skipped before,
too; otherwise a checkout can cause a file on disk whose name
coincides with a newly added outside-worktree file to be deleted.

Do I understand correctly?

> +++ b/unpack-trees.c
> @@ -1091,6 +1091,8 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
>  	if (!old) {
>  		if (verify_absent(merge, "overwritten", o))
>  			return -1;
> +		if (!o->skip_sparse_checkout && will_have_skip_worktree(merge, o))
> +			update |= CE_SKIP_WORKTREE;
>  		invalidate_ce_path(merge, o);
>  	} else if (!(old->ce_flags & CE_CONFLICTED)) {
>  		/*

Looks sane.

Thanks for the fixes,
Jonathan