Re: [PATCH 16/20] strvec: add functions to replace and remove strings

[Eric Sunshine <sunshine@sunshineco.com>]

On Thu, May 23, 2024 at 8:27 AM Patrick Steinhardt <ps@pks.im> wrote:
> Add two functions that allow to replace and remove strings contained in
> the strvec. This will be used by a subsequent commit that refactors
> git-mv(1).
> [...]
> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> ---
> diff --git a/strvec.c b/strvec.c
> @@ -56,6 +56,26 @@ void strvec_pushv(struct strvec *array, const char **items)
> +const char *strvec_replace(struct strvec *array, size_t idx, const char *replacement)
> +{
> +       char *to_free;
> +       if (idx >= array->nr)
> +               BUG("index outside of array boundary");
> +       to_free = (char *) array->v[idx];
> +       array->v[idx] = xstrdup(replacement);
> +       free(to_free);
> +       return array->v[idx];
> +}

The reason you delay calling free() until after xstrdup() is to
protect against the case when `replacement` is a substring of the
string already stored at `v[idx]`, correct?