Re: [PATCH v16 Part II 6/8] bisect--helper: `get_terms` & `bisect_terms` shell function in C

> Reimplement the `get_terms` and `bisect_terms` shell function in C and
> add `bisect-terms` subcommand to `git bisect--helper` to call it from
> git-bisect.sh .
> 
> Using `--bisect-terms` subcommand is a temporary measure to port shell
> function in C so as to use the existing test suite. As more functions
> are ported, this subcommand will be retired but its implementation will
> be called by some other methods.
> 
> Also use error() to report "no terms defined" and accordingly change the
> test in t6030.
> 
> Mentored-by: Lars Schneider <larsxschneider@gmail.com>
> Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> Signed-off-by: Pranit Bauva <pranit.bauva@gmail.com>
> ---
>  builtin/bisect--helper.c    | 69 +++++++++++++++++++++++++++++++++++++++++++--
>  git-bisect.sh               | 35 ++---------------------
>  t/t6030-bisect-porcelain.sh |  2 +-
>  3 files changed, 70 insertions(+), 36 deletions(-)
> 
> diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
> index 0f9c3e63821b8..ab0580ce0089a 100644
> --- a/builtin/bisect--helper.c
> +++ b/builtin/bisect--helper.c
> @@ -23,6 +23,7 @@ static const char * const git_bisect_helper_usage[] = {
>  	N_("git bisect--helper --bisect-write <state> <revision> <good_term> <bad_term> [<nolog>]"),
>  	N_("git bisect--helper --bisect-check-and-set-terms <command> <good_term> <bad_term>"),
>  	N_("git bisect--helper --bisect-next-check [<term>] <good_term> <bad_term>"),
> +	N_("git bisect--helper --bisect-terms [--term-good | --term-old | --term-bad | --term-new]"),
>  	NULL
>  };
>  
> @@ -344,6 +345,62 @@ static int bisect_next_check(const struct bisect_terms *terms,
>  	return retval;
>  }
>  
> +static int get_terms(struct bisect_terms *terms)
> +{
> +	struct strbuf str = STRBUF_INIT;
> +	FILE *fp = NULL;
> +	int res = 0;
> +
> +	fp = fopen(git_path_bisect_terms(), "r");
> +	if (!fp)
> +		goto fail;
> +
> +	free_terms(terms);
> +	strbuf_getline_lf(&str, fp);
> +	terms->term_bad = strbuf_detach(&str, NULL);
> +	strbuf_getline_lf(&str, fp);
> +	terms->term_good = strbuf_detach(&str, NULL);
> +	goto finish;
> +
> +fail:
> +	res = -1;
> +finish:
> +	if (fp)
> +		fclose(fp);
> +	strbuf_release(&str);
> +	return res;
> +}
> +
> +static int bisect_terms(struct bisect_terms *terms, const char **argv, int argc)
> +{
> +	int i;
> +
> +	if (get_terms(terms))
> +		return error(_("no terms defined"));
> +
> +	if (argc > 1)
> +		return error(_("--bisect-term requires exactly one argument"));
> +
> +	if (argc == 0)
> +		return !printf(_("Your current terms are %s for the old state\n"
> +				 "and %s for the new state.\n"),
> +				 terms->term_good, terms->term_bad);

> +
> +	for (i = 0; i < argc; i++) {
> +		if (!strcmp(argv[i], "--term-good"))> +			printf(_("%s\n"), terms->term_good);
> +		else if (!strcmp(argv[i], "--term-bad"))
> +			printf(_("%s\n"), terms->term_bad);
> +		else

> +			error(_("BUG: invalid argument %s for 'git bisect terms'.\n"
> +				  "Supported options are: "
> +				  "--term-good|--term-old and "
> +				  "--term-bad|--term-new."), argv[i]);
> +	}
> +
> +	return 0;
> +}
> +