Re: [PATCH v8 1/2] parse-options.c: make OPTION__COUNTUP consider negative values

[Junio C Hamano <gitster@pobox.com>]

Pranit Bauva <pranit.bauva@gmail.com> writes:

> The reason to make it consider negative values or more specifically
> "unspecified" values is to give the ability to differentiate between
> once, multiple time or with --no-option.
>
> Eg. :
> initialize verbose = -1
> `git commit` => verbose = -1
> `git commit -v` => verbose = 1
> `git commit -v -v` => verbose = 2
> `git commit --no-verbose` => verbose = 0

A few more things I noticed about this are:

 - Many uses of COUNTUP has now been replaced with BOOL and what
   remains are verbose/quiet/force.

 - This change will not affect existing users of COUNTUP at all, as
   long as they use the initial value of 0 (or more), as there is no
   mechanism to decrement.  The only thing the command line can do
   is to reset it to zero with "--no-foo".

So it seems a safe and sensible change.  Even though I suspect that
the justification can be written more clearly, I am not sure if it
worth the extra effort.

>
> Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
>
> ---
> The discussion about this patch:
> [1] : http://thread.gmane.org/gmane.comp.version-control.git/289027
>
> Previous version of the patch:
> [v1] : http://thread.gmane.org/gmane.comp.version-control.git/289061
>
> Changes introduced:
> Use a different language in commit message to make the change and its
> utility more clear.
> ---
>  Documentation/technical/api-parse-options.txt | 6 ++++--
>  parse-options.c                               | 8 +++++++-
>  2 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt
> index 5f0757d..a908d8a 100644
> --- a/Documentation/technical/api-parse-options.txt
> +++ b/Documentation/technical/api-parse-options.txt
> @@ -144,8 +144,10 @@ There are some macros to easily define options:
>  
>  `OPT_COUNTUP(short, long, &int_var, description)`::
>  	Introduce a count-up option.
> -	`int_var` is incremented on each use of `--option`, and
> -	reset to zero with `--no-option`.
> +	If the `int_var` is negative and `--option` is absent,
> +	then it will retain its value. Otherwise it will first set
> +	`int_var` to 0 and then increment it on each use of `--option`,
> +	and reset to zero with `--no-option`.
>  
>  `OPT_BIT(short, long, &int_var, description, mask)`::
>  	Introduce a boolean option.
> diff --git a/parse-options.c b/parse-options.c
> index 47a9192..86d30bd 100644
> --- a/parse-options.c
> +++ b/parse-options.c
> @@ -110,7 +110,13 @@ static int get_value(struct parse_opt_ctx_t *p,
>  		return 0;
>  
>  	case OPTION_COUNTUP:
> -		*(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
> +		if (unset)
> +			*(int *)opt->value = 0;
> +		else {
> +			if (*(int *)opt->value < 0)
> +				*(int *)opt->value = 0;
> +			*(int *)opt->value += 1;
> +		}
>  		return 0;
>  
>  	case OPTION_SET_INT:
>
> --
> https://github.com/git/git/pull/213