Re: [PATCH 09/23] dir: fix off by one errors for ignored and untracked entries

> In `treat_directory()` we perform some logic to handle ignored and
> untracked entries. When populating a directory with entries we first
> save the current number of ignored/untracked entries and then populate
> new entries at the end of our arrays that keep track of those entries.
> When we figure out that all entries have been ignored/are untracked we
> then remove this tail of entries from those vectors again. But there is
> an off by one error in both paths that causes us to not free the first
> ignored and untracked entries, respectively.
>
> Fix these off-by-one errors to plug the resulting leak. While at it,
> massage the code a bit to match our modern code style.
>
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---
>  dir.c                                              | 6 ++----
>  t/t3011-common-prefixes-and-directory-traversal.sh | 1 +
>  t/t7061-wtstatus-ignore.sh                         | 1 +
>  t/t7521-ignored-mode.sh                            | 1 +
>  4 files changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/dir.c b/dir.c
> index 5a23376bdae..787bcb7a1a4 100644
> --- a/dir.c
> +++ b/dir.c
> @@ -2135,8 +2135,7 @@ static enum path_treatment treat_directory(struct dir_struct *dir,
>  			 */
>  			state = path_none;
>  		} else {
> -			int i;
> -			for (i = old_ignored_nr + 1; i<dir->ignored_nr; ++i)
> +			for (int i = old_ignored_nr; i < dir->ignored_nr; i++)
>  				FREE_AND_NULL(dir->ignored[i]);
>  			dir->ignored_nr = old_ignored_nr;