[v3,11/15] bisect: move even the command-line parsing to `bisect--helper`

Commit Message

Johannes Schindelin May 21, 2022, 2:49 p.m. UTC

From: Johannes Schindelin <[e-mail]>

On our journey to a fully built-in `git bisect`, this is the
one of the last steps.

Side note: The `parse-options` API is not at all set up to parse
subcommands such as `git bisect start`, `git bisect reset`, etc.
Instead of fighting an up-hill battle trying to "fix" that, we simply
roll the same type of manual subcommand parsing as we already do e.g.
in `builtin/bundle.c`.

Signed-off-by: Johannes Schindelin <[e-mail]>
---
 builtin/bisect--helper.c | 91 ++++++++++++----------------------------
 git-bisect.sh            | 49 +---------------------
 2 files changed, 27 insertions(+), 113 deletions(-)

Comments

Ævar Arnfjörð Bjarmason May 21, 2022, 4:52 p.m. UTC | #1

On Sat, May 21 2022, Johannes Schindelin via GitGitGadget wrote:

> From: Johannes Schindelin <[e-mail]>
>
> On our journey to a fully built-in `git bisect`, this is the
> one of the last steps.
>
> Side note: The `parse-options` API is not at all set up to parse
> subcommands such as `git bisect start`, `git bisect reset`, etc.


It seems that since v2 you fixed the bug of "-h" starting a bisection
session, as noted in :
https://lore.kernel.org/git/[e-mail]/


But that problem seems to still be with us in other forms, e.g. just one
thing I tried (the very first thing) was the command I was testing in
10/15, and:
    
    ./git bisect--helper  --bisect-terms 1 2 ; echo $?
    You need to start by "git bisect start"
    
    Do you want me to do it for you [Y/n]? ^C

so that's buggy too.

> Instead of fighting an up-hill battle trying to "fix" that, we simply
> roll the same type of manual subcommand parsing as we already do e.g.
> in `builtin/bundle.c`.

This is particularly confusing because that would be a good approach (as
I pointed out in a previous round), but the end-state here isn't at all
like builtin/bundle.c. I.e. in that case we have a top-level strcmp()
chain dispatching to parse_options() for the sub-command, which would
solve your problems here...

Patch

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 824f84ae76f..89ff688a4a2 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -1276,108 +1276,69 @@  static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
 
 int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
 {
-	enum {
-		BISECT_START = 1,
-		BISECT_STATE,
-		BISECT_TERMS,
-		BISECT_SKIP,
-		BISECT_NEXT,
-		BISECT_RESET,
-		BISECT_VISUALIZE,
-		BISECT_REPLAY,
-		BISECT_LOG,
-		BISECT_RUN,
-	} cmdmode = 0;
 	int res = 0;
 	struct option options[] = {
-		OPT_CMDMODE(0, "bisect-start", &cmdmode,
-			 N_("start the bisect session"), BISECT_START),
-		OPT_CMDMODE(0, "bisect-state", &cmdmode,
-			 N_("mark the state of ref (or refs)"), BISECT_STATE),
-		OPT_CMDMODE(0, "bisect-terms", &cmdmode,
-			 N_("print out the bisect terms"), BISECT_TERMS),
-		OPT_CMDMODE(0, "bisect-skip", &cmdmode,
-			 N_("skip some commits for checkout"), BISECT_SKIP),
-		OPT_CMDMODE(0, "bisect-next", &cmdmode,
-			 N_("find the next bisection commit"), BISECT_NEXT),
-		OPT_CMDMODE(0, "bisect-reset", &cmdmode,
-			 N_("reset the bisection state"), BISECT_RESET),
-		OPT_CMDMODE(0, "bisect-visualize", &cmdmode,
-			 N_("visualize the bisection"), BISECT_VISUALIZE),
-		OPT_CMDMODE(0, "bisect-replay", &cmdmode,
-			 N_("replay the bisection process from the given file"), BISECT_REPLAY),
-		OPT_CMDMODE(0, "bisect-log", &cmdmode,
-			 N_("list the bisection steps so far"), BISECT_LOG),
-		OPT_CMDMODE(0, "bisect-run", &cmdmode,
-			 N_("use <cmd>... to automatically bisect"), BISECT_RUN),
 		OPT_END()
 	};
 	struct bisect_terms terms = { .term_good = NULL, .term_bad = NULL };
+	const char *command = argc > 1 ? argv[1] : "help";
 
-	argc = parse_options(argc, argv, prefix, options,
-			     git_bisect_helper_usage,
-			     PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_UNKNOWN);
+	if (!strcmp("-h", command) || !strcmp("help", command))
+		usage_with_options(git_bisect_helper_usage, options);
 
-	switch (cmdmode ? cmdmode : BISECT_STATE) {
-	case BISECT_START:
+	argc -= 2;
+	argv += 2;
+
+	if (!strcmp("start", command)) {
 		set_terms(&terms, "bad", "good");
 		res = bisect_start(&terms, argv, argc);
-		break;
-	case BISECT_TERMS:
+	} else if (!strcmp("terms", command)) {
 		if (argc > 1)
-			die(_("--bisect-terms requires 0 or 1 argument"));
+			die(_("'terms' requires 0 or 1 argument"));
 		res = bisect_terms(&terms, argc == 1 ? argv[0] : NULL);
-		break;
-	case BISECT_SKIP:
+	} else if (!strcmp("skip", command)) {
 		set_terms(&terms, "bad", "good");
 		get_terms(&terms);
 		res = bisect_skip(&terms, argv, argc);
-		break;
-	case BISECT_NEXT:
+	} else if (!strcmp("next", command)) {
 		if (argc)
-			die(_("--bisect-next requires 0 arguments"));
+			die(_("'next' requires 0 arguments"));
 		get_terms(&terms);
 		res = bisect_next(&terms, prefix);
-		break;
-	case BISECT_RESET:
+	} else if (!strcmp("reset", command)) {
 		if (argc > 1)
-			die(_("--bisect-reset requires either no argument or a commit"));
+			die(_("'reset' requires either no argument or a commit"));
 		res = bisect_reset(argc ? argv[0] : NULL);
-		break;
-	case BISECT_VISUALIZE:
+	} else if (one_of(command, "visualize", "view", NULL)) {
 		get_terms(&terms);
 		res = bisect_visualize(&terms, argv, argc);
-		break;
-	case BISECT_REPLAY:
+	} else if (!strcmp("replay", command)) {
 		if (argc != 1)
 			die(_("no logfile given"));
 		set_terms(&terms, "bad", "good");
 		res = bisect_replay(&terms, argv[0]);
-		break;
-	case BISECT_LOG:
+	} else if (!strcmp("log", command)) {
 		if (argc)
-			die(_("--bisect-log requires 0 arguments"));
+			die(_("'log' requires 0 arguments"));
 		res = bisect_log();
-		break;
-	case BISECT_RUN:
+	} else if (!strcmp("run", command)) {
 		if (!argc)
 			die(_("bisect run failed: no command provided."));
 		get_terms(&terms);
 		res = bisect_run(&terms, argv, argc);
-		break;
-	case BISECT_STATE:
+	} else {
 		set_terms(&terms, "bad", "good");
 		get_terms(&terms);
-		if (!cmdmode &&
-		    (!argc || check_and_set_terms(&terms, argv[0]))) {
-			char *msg = xstrfmt(_("unknown command: '%s'"), argv[0]);
+		if (check_and_set_terms(&terms, command)) {
+			char *msg = xstrfmt(_("unknown command: '%s'"), command);
 			usage_msg_opt(msg, git_bisect_helper_usage, options);
 		}
+		/* shift the `command` back in */
+		argc++;
+		argv--;
 		res = bisect_state(&terms, argv, argc);
-		break;
-	default:
-		BUG("unknown subcommand %d", cmdmode);
 	}
+
 	free_terms(&terms);
 
 	/*
diff --git a/git-bisect.sh b/git-bisect.sh
index fbf56649d7d..028d39cd9ce 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -34,51 +34,4 @@  Please use "git help bisect" to get the full man page.'
 OPTIONS_SPEC=
 . git-sh-setup
 
-TERM_BAD=bad
-TERM_GOOD=good
-
-get_terms () {
-	if test -s "$GIT_DIR/BISECT_TERMS"
-	then
-		{
-		read TERM_BAD
-		read TERM_GOOD
-		} <"$GIT_DIR/BISECT_TERMS"
-	fi
-}
-
-case "$#" in
-0)
-	usage ;;
-*)
-	cmd="$1"
-	get_terms
-	shift
-	case "$cmd" in
-	help)
-		git bisect -h ;;
-	start)
-		git bisect--helper --bisect-start "$@" ;;
-	bad|good|new|old|"$TERM_BAD"|"$TERM_GOOD")
-		git bisect--helper "$cmd" "$@" ;;
-	skip)
-		git bisect--helper --bisect-skip "$@" || exit;;
-	next)
-		# Not sure we want "next" at the UI level anymore.
-		git bisect--helper --bisect-next "$@" || exit ;;
-	visualize|view)
-		git bisect--helper --bisect-visualize "$@" || exit;;
-	reset)
-		git bisect--helper --bisect-reset "$@" ;;
-	replay)
-		git bisect--helper --bisect-replay "$@" || exit;;
-	log)
-		git bisect--helper --bisect-log || exit ;;
-	run)
-		git bisect--helper --bisect-run "$@" || exit;;
-	terms)
-		git bisect--helper --bisect-terms "$@" || exit;;
-	*)
-		usage ;;
-	esac
-esac
+exec git bisect--helper "$@"