Re: [PATCH 1/5 v4] diff: parse detached options like -S foo

> Change the option parsing logic in revision.c to accept detached forms
> like `-S foo' in addition to `-Sfoo'. The rest of git already accepted
> this form, but revision.c still used its own option parsing.
>
> This patch does not handle --stat-name-width and --stat-width, which are
> special-cases where diff_long_opt do not apply. They are handled in a
> separate patch to ease review.
>
> Original patch by Matthieu Moy, plus refactoring by Jonathan Nieder.
>
> Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
> ---
>  diff.c                       |   87 ++++++++++++++++++++++++++++++++++--------
>  diff.h                       |    7 +++
>  t/t4013-diff-various.sh      |    5 ++
>  t/t4013/diff.log_-S_F_master |    7 +++
>  t/t4202-log.sh               |   12 ++---
>  5 files changed, 95 insertions(+), 23 deletions(-)
>  create mode 100644 t/t4013/diff.log_-S_F_master
>
> diff --git a/diff.c b/diff.c
> index 17873f3..d89ea20 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -2990,9 +2990,50 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
>  
>  static int diff_scoreopt_parse(const char *opt);
>  
> +static inline int short_opt(char opt, const char **argv,
> +			    const char **optarg)
> +{
> +	const char *arg = argv[0];
> +	if (arg[0] != '-' || arg[1] != opt)
> +		return 0;
> +	if (arg[2] != '\0') {
> +		*optarg = arg + strlen("-c");