Re: [PATCH v3 07/12] unpack-trees: stop recursing into sparse directories

>
> From: Derrick Stolee <dstolee@microsoft.com>
>
> When walking trees using traverse_trees_recursive() and
> unpack_callback(), we must not attempt to walk into a sparse directory
> entry. There are no index entries within that directory to compare to
> the tree object at that position, so skip over the entries of that tree.
>
> This code is used in many places, so the only way to test it is to start
> removing the command_requres_full_index option from one builtin at a
> time and carefully test that its use of unpack_trees() behaves correctly
> with a sparse-index. Such tests will be added by later changes.
>
> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
> ---
>  diff-lib.c     | 6 ++++++
>  unpack-trees.c | 7 +++++--
>  2 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/diff-lib.c b/diff-lib.c
> index b73cc1859a49..d5e7e01132ee 100644
> --- a/diff-lib.c
> +++ b/diff-lib.c
> @@ -322,6 +322,9 @@ static void show_new_file(struct rev_info *revs,
>         unsigned int mode;
>         unsigned dirty_submodule = 0;
>
> +       if (S_ISSPARSEDIR(new_file->ce_mode))
> +               return;
> +

>         /*
>          * New file in the index: it might actually be different in
>          * the working tree.
> @@ -343,6 +346,9 @@ static int show_modified(struct rev_info *revs,
>         const struct object_id *oid;
>         unsigned dirty_submodule = 0;
>
> +       if (S_ISSPARSEDIR(new_entry->ce_mode))
> +               return 0;
> +

>         if (get_stat_data(new_entry, &oid, &mode, cached, match_missing,
>                           &dirty_submodule, &revs->diffopt) < 0) {
>                 if (report_missing)
> diff --git a/unpack-trees.c b/unpack-trees.c
> index ef6a2b1c951c..703b0bdc9dfd 100644
> --- a/unpack-trees.c
> +++ b/unpack-trees.c
> @@ -1261,6 +1261,7 @@ static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, str
>         struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
>         struct unpack_trees_options *o = info->data;
>         const struct name_entry *p = names;
> +       unsigned unpack_tree = 1;
>
>         /* Find first entry with a real name (we could use "mask" too) */
>         while (!p->mode)
> @@ -1307,7 +1308,8 @@ static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, str
>                 }
>         }
>
> -       if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
> +       if (unpack_tree &&
> +           unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
>                 return -1;
>
>         if (o->merge && src[0]) {
> @@ -1337,7 +1339,8 @@ static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, str
>                         }
>                 }
>
> -               if (traverse_trees_recursive(n, dirmask, mask & ~dirmask,
> +               if (unpack_tree &&
> +                   traverse_trees_recursive(n, dirmask, mask & ~dirmask,
>                                              names, info) < 0)
>                         return -1;
>                 return mask;
> --
> gitgitgadget