[PATCH] bisect: report actual bisect_state() argument on error

["René Scharfe" <l.s.r@web.de>]

The strvec "args" in bisect_run() is initialized and cleared, but never
added to.  Nevertheless its first member is printed when reporting a
bisect_state() error.  That's not useful, since it's always NULL.

Before d1bbbe45df (bisect--helper: reimplement `bisect_run` shell
function in C, 2021-09-13) the new state was reported if it could not
been set.  Reinstate that behavior and remove the unused strvec.

Reported-by: Ramkumar Ramachandra <r@artagnon.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
---
This doesn't fix your problem, only replace the "(null)" in the error
messages with the actual state name -- which may be useful for
diagnosing its cause, though.

Patch generated with --function-context for easier review.

 builtin/bisect--helper.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/builtin/bisect--helper.c b/builtin/bisect--helper.c
index 28a2e6a575..1dbc6294ef 100644
--- a/builtin/bisect--helper.c
+++ b/builtin/bisect--helper.c
@@ -1092,80 +1092,76 @@ static int bisect_visualize(struct bisect_terms *terms, const char **argv, int a
 static int bisect_run(struct bisect_terms *terms, const char **argv, int argc)
 {
 	int res = BISECT_OK;
 	struct strbuf command = STRBUF_INIT;
-	struct strvec args = STRVEC_INIT;
 	struct strvec run_args = STRVEC_INIT;
 	const char *new_state;
 	int temporary_stdout_fd, saved_stdout;

 	if (bisect_next_check(terms, NULL))
 		return BISECT_FAILED;

 	if (argc)
 		sq_quote_argv(&command, argv);
 	else {
 		error(_("bisect run failed: no command provided."));
 		return BISECT_FAILED;
 	}

 	strvec_push(&run_args, command.buf);

 	while (1) {
-		strvec_clear(&args);
-
 		printf(_("running %s\n"), command.buf);
 		res = run_command_v_opt(run_args.v, RUN_USING_SHELL);

 		if (res < 0 || 128 <= res) {
 			error(_("bisect run failed: exit code %d from"
 				" '%s' is < 0 or >= 128"), res, command.buf);
 			strbuf_release(&command);
 			return res;
 		}

 		if (res == 125)
 			new_state = "skip";
 		else if (!res)
 			new_state = terms->term_good;
 		else
 			new_state = terms->term_bad;

 		temporary_stdout_fd = open(git_path_bisect_run(), O_CREAT | O_WRONLY | O_TRUNC, 0666);

 		if (temporary_stdout_fd < 0)
 			return error_errno(_("cannot open file '%s' for writing"), git_path_bisect_run());

 		fflush(stdout);
 		saved_stdout = dup(1);
 		dup2(temporary_stdout_fd, 1);

 		res = bisect_state(terms, &new_state, 1);

 		fflush(stdout);
 		dup2(saved_stdout, 1);
 		close(saved_stdout);
 		close(temporary_stdout_fd);

 		print_file_to_stdout(git_path_bisect_run());

 		if (res == BISECT_ONLY_SKIPPED_LEFT)
 			error(_("bisect run cannot continue any more"));
 		else if (res == BISECT_INTERNAL_SUCCESS_MERGE_BASE) {
 			printf(_("bisect run success"));
 			res = BISECT_OK;
 		} else if (res == BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND) {
 			printf(_("bisect found first bad commit"));
 			res = BISECT_OK;
 		} else if (res) {
 			error(_("bisect run failed: 'git bisect--helper --bisect-state"
-			" %s' exited with error code %d"), args.v[0], res);
+			" %s' exited with error code %d"), new_state, res);
 		} else {
 			continue;
 		}

 		strbuf_release(&command);
-		strvec_clear(&args);
 		strvec_clear(&run_args);
 		return res;
 	}
 }
--
2.34.1