Re: [PATCH v3 2/3] bisect--helper: move all subcommands into their own functions

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

On Thu, Nov 10 2022, Đoàn Trần Công Danh wrote:

> In a later change, we will use OPT_SUBCOMMAND to parse sub-commands to
> avoid consuming non-option opts.
>
> Since OPT_SUBCOMMAND needs a function pointer to operate,
> let's move it now.
>
> Signed-off-by: Đoàn Trần Công Danh <congdanhqx@gmail.com>
> ---
>  builtin/bisect--helper.c | 155 ++++++++++++++++++++++++++++++---------
>  1 file changed, 121 insertions(+), 34 deletions(-)
>
> diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
> index 5ec2e67f59..d425555d1f 100644
> --- a/builtin/bisect--helper.c
> +++ b/builtin/bisect--helper.c
> @@ -1279,6 +1279,117 @@ static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
>  	return res;
>  }
>  
> +static int cmd_bisect__reset(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	if (argc > 1)
> +		return error(_("--bisect-reset requires either no argument or a commit"));
> +	return bisect_reset(argc ? argv[0] : NULL);
> +}
> +
> +static int cmd_bisect__terms(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	if (argc > 1)
> +		return error(_("--bisect-terms requires 0 or 1 argument"));
> +	res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__start(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	set_terms(&terms, "bad", "good");
> +	res = bisect_start(&terms, argv, argc);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__next(int argc, const char **argv UNUSED, const char *prefix)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	if (argc)
> +		return error(_("--bisect-next requires 0 arguments"));
> +	get_terms(&terms);
> +	res = bisect_next(&terms, prefix);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__state(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	set_terms(&terms, "bad", "good");
> +	get_terms(&terms);
> +	res = bisect_state(&terms, argv, argc);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__log(int argc, const char **argv UNUSED, const char *prefix UNUSED)
> +{
> +	if (argc)
> +		return error(_("--bisect-log requires 0 arguments"));
> +	return bisect_log();
> +}
> +
> +static int cmd_bisect__replay(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	if (argc != 1)
> +		return error(_("no logfile given"));
> +	set_terms(&terms, "bad", "good");
> +	res = bisect_replay(&terms, argv[0]);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__skip(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	set_terms(&terms, "bad", "good");
> +	get_terms(&terms);
> +	res = bisect_skip(&terms, argv, argc);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__visualize(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	get_terms(&terms);
> +	res = bisect_visualize(&terms, argv, argc);
> +	free_terms(&terms);
> +	return res;
> +}
> +
> +static int cmd_bisect__run(int argc, const char **argv, const char *prefix UNUSED)
> +{
> +	int res;
> +	struct bisect_terms terms = { 0 };
> +
> +	if (!argc)
> +		return error(_("bisect run failed: no command provided."));
> +	get_terms(&terms);
> +	res = bisect_run(&terms, argv, argc);
> +	free_terms(&terms);
> +	return res;
> +}
> +
>  int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  {
>  	enum {
> @@ -1318,8 +1429,6 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  			 N_("use <cmd>... to automatically bisect"), BISECT_RUN),
>  		OPT_END()
>  	};
> -	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
> -
>  	argc = parse_options(argc, argv, prefix, options,
>  			     git_bisect_helper_usage,
>  			     PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_UNKNOWN_OPT);
> @@ -1329,60 +1438,38 @@ int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
>  
>  	switch (cmdmode) {
>  	case BISECT_RESET:
> -		if (argc > 1)
> -			return error(_("--bisect-reset requires either no argument or a commit"));
> -		res = bisect_reset(argc ? argv[0] : NULL);
> +		res = cmd_bisect__reset(argc, argv, prefix);
>  		break;
>  	case BISECT_TERMS:
> -		if (argc > 1)
> -			return error(_("--bisect-terms requires 0 or 1 argument"));
> -		res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
> +		res = cmd_bisect__terms(argc, argv, prefix);
>  		break;
>  	case BISECT_START:
> -		set_terms(&terms, "bad", "good");
> -		res = bisect_start(&terms, argv, argc);
> +		res = cmd_bisect__start(argc, argv, prefix);
>  		break;
>  	case BISECT_NEXT:
> -		if (argc)
> -			return error(_("--bisect-next requires 0 arguments"));
> -		get_terms(&terms);
> -		res = bisect_next(&terms, prefix);
> +		res = cmd_bisect__next(argc, argv, prefix);
>  		break;
>  	case BISECT_STATE:
> -		set_terms(&terms, "bad", "good");
> -		get_terms(&terms);
> -		res = bisect_state(&terms, argv, argc);
> +		res = cmd_bisect__state(argc, argv, prefix);
>  		break;
>  	case BISECT_LOG:
> -		if (argc)
> -			return error(_("--bisect-log requires 0 arguments"));
> -		res = bisect_log();
> +		res = cmd_bisect__log(argc, argv, prefix);
>  		break;
>  	case BISECT_REPLAY:
> -		if (argc != 1)
> -			return error(_("no logfile given"));
> -		set_terms(&terms, "bad", "good");
> -		res = bisect_replay(&terms, argv[0]);
> +		res = cmd_bisect__replay(argc, argv, prefix);
>  		break;
>  	case BISECT_SKIP:
> -		set_terms(&terms, "bad", "good");
> -		get_terms(&terms);
> -		res = bisect_skip(&terms, argv, argc);
> +		res = cmd_bisect__skip(argc, argv, prefix);
>  		break;
>  	case BISECT_VISUALIZE:
> -		get_terms(&terms);
> -		res = bisect_visualize(&terms, argv, argc);
> +		res = cmd_bisect__visualize(argc, argv, prefix);
>  		break;
>  	case BISECT_RUN:
> -		if (!argc)
> -			return error(_("bisect run failed: no command provided."));
> -		get_terms(&terms);
> -		res = bisect_run(&terms, argv, argc);
> +		res = cmd_bisect__run(argc, argv, prefix);
>  		break;
>  	default:
>  		BUG("unknown subcommand %d", cmdmode);
>  	}
> -	free_terms(&terms);
>  
>  	/*
>  	 * Handle early success

FWIW I tried my suggestion in an earlier review of factoring this into a
function, I don't know if it's worth it, but it is a net reduction in
lines. Some of the error messages are changed as a result.

If you think the end result looks better, feel free to pick it up /
adapt it etc with my Signed-off-by.

 builtin/bisect--helper.c | 109 +++++++++++++++++++----------------------------
 1 file changed, 43 insertions(+), 66 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index d4d813ebfce..e5a5261f9f2 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -469,8 +469,11 @@ static int get_terms(struct bisect_terms *terms)
 	return res;
 }
 
-static int bisect_terms(struct bisect_terms *terms, const char *option)
+static int bisect_terms(struct bisect_terms *terms, const char **argv,
+			int argc)
 {
+	const char *option = argc == 1 ? argv[0] : NULL;
+
 	if (get_terms(terms))
 		return error(_("no terms defined"));
 
@@ -1024,7 +1027,7 @@ static int process_replay_line(struct bisect_terms *terms, struct strbuf *line)
 		struct strvec argv = STRVEC_INIT;
 		int res;
 		sq_dequote_to_strvec(rev, &argv);
-		res = bisect_terms(terms, argv.nr == 1 ? argv.v[0] : NULL);
+		res = bisect_terms(terms, argv.v, argv.nr);
 		strvec_clear(&argv);
 		return res;
 	}
@@ -1033,8 +1036,10 @@ static int process_replay_line(struct bisect_terms *terms, struct strbuf *line)
 	return -1;
 }
 
-static enum bisect_error bisect_replay(struct bisect_terms *terms, const char *filename)
+static int bisect_replay(struct bisect_terms *terms, const char **argv,
+			int argc)
 {
+	const char *filename = argv[0];
 	FILE *fp = NULL;
 	enum bisect_error res = BISECT_OK;
 	struct strbuf line = STRBUF_INIT;
@@ -1279,6 +1284,24 @@ static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
 	return res;
 }
 
+typedef int (*cmd_bisect_fn_t)(struct bisect_terms *terms, const char **argv, int argc);
+static int terms_cmd(int argc, const char **argv, const char *prefix UNUSED,
+		     cmd_bisect_fn_t fn, int set, int errcond,
+		     const char *errmsg, const char *errcmd)
+{
+	int res;
+	struct bisect_terms terms = { 0 };
+
+	if (errcond)
+		return error(_(errmsg), errcmd);
+	if (set)
+		set_terms(&terms, "bad", "good");
+	get_terms(&terms);
+	res = fn(&terms, argv, argc);
+	free_terms(&terms);
+	return res;
+}
+
 static int cmd_bisect__reset(int argc, const char **argv, const char *prefix UNUSED)
 {
 	if (argc > 1)
@@ -1286,27 +1309,15 @@ static int cmd_bisect__reset(int argc, const char **argv, const char *prefix UNU
 	return bisect_reset(argc ? argv[0] : NULL);
 }
 
-static int cmd_bisect__terms(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__terms(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	if (argc > 1)
-		return error(_("--bisect-terms requires 0 or 1 argument"));
-	res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_terms, 0, argc > 1,
+			 N_("'bisect %s' requires 0 or 1 argument"), "terms");
 }
 
-static int cmd_bisect__start(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__start(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	set_terms(&terms, "bad", "good");
-	res = bisect_start(&terms, argv, argc);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_start, 1, 0, NULL, NULL);
 }
 
 static int cmd_bisect__next(int argc, const char **argv UNUSED, const char *prefix)
@@ -1322,16 +1333,9 @@ static int cmd_bisect__next(int argc, const char **argv UNUSED, const char *pref
 	return res;
 }
 
-static int cmd_bisect__state(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__state(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	set_terms(&terms, "bad", "good");
-	get_terms(&terms);
-	res = bisect_state(&terms, argv, argc);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_state, 1, 0, NULL, NULL);
 }
 
 static int cmd_bisect__log(int argc, const char **argv UNUSED, const char *prefix UNUSED)
@@ -1341,53 +1345,26 @@ static int cmd_bisect__log(int argc, const char **argv UNUSED, const char *prefi
 	return bisect_log();
 }
 
-static int cmd_bisect__replay(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__replay(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	if (argc != 1)
-		return error(_("no logfile given"));
-	set_terms(&terms, "bad", "good");
-	res = bisect_replay(&terms, argv[0]);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_replay, 1, argc != 1,
+			 N_("'bisect %s': no logfile given"), "replay");
 }
 
-static int cmd_bisect__skip(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__skip(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	set_terms(&terms, "bad", "good");
-	get_terms(&terms);
-	res = bisect_skip(&terms, argv, argc);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_skip, 1, 0, NULL, NULL);
 }
 
-static int cmd_bisect__visualize(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__visualize(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	get_terms(&terms);
-	res = bisect_visualize(&terms, argv, argc);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_visualize, 0, 0, NULL, NULL);
 }
 
-static int cmd_bisect__run(int argc, const char **argv, const char *prefix UNUSED)
+static int cmd_bisect__run(int argc, const char **argv, const char *prefix)
 {
-	int res;
-	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
-
-	if (!argc)
-		return error(_("bisect run failed: no command provided."));
-	get_terms(&terms);
-	res = bisect_run(&terms, argv, argc);
-	free_terms(&terms);
-	return res;
+	return terms_cmd(argc, argv, prefix, bisect_run, 0, !argc,
+			 N_("bisect %s failed: no command provided."), "run");
 }
 
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)