sequencer: die on config error when saving replay opts

When we start picking a range of revisions we save the replay
options that are required to restore state when interrupting and
later continuing picking the revisions. However, we do not check
the return values of the `git_config_set` functions, which may
lead us to store incomplete information. As this may lead us to
fail when trying to continue the sequence the error can be fatal.

Fix this by dying immediately when we are unable to write back
any replay option.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

sequencer.c

@@ -933,31 +933,31 @@ static void save_opts(struct replay_opts *opts)
 	const char *opts_file = git_path_opts_file();
 
 	if (opts->no_commit)
-		git_config_set_in_file(opts_file, "options.no-commit", "true");
+		git_config_set_in_file_or_die(opts_file, "options.no-commit", "true");
 	if (opts->edit)
-		git_config_set_in_file(opts_file, "options.edit", "true");
+		git_config_set_in_file_or_die(opts_file, "options.edit", "true");
 	if (opts->signoff)
-		git_config_set_in_file(opts_file, "options.signoff", "true");
+		git_config_set_in_file_or_die(opts_file, "options.signoff", "true");
 	if (opts->record_origin)
-		git_config_set_in_file(opts_file, "options.record-origin", "true");
+		git_config_set_in_file_or_die(opts_file, "options.record-origin", "true");
 	if (opts->allow_ff)
-		git_config_set_in_file(opts_file, "options.allow-ff", "true");
+		git_config_set_in_file_or_die(opts_file, "options.allow-ff", "true");
 	if (opts->mainline) {
 		struct strbuf buf = STRBUF_INIT;
 		strbuf_addf(&buf, "%d", opts->mainline);
-		git_config_set_in_file(opts_file, "options.mainline", buf.buf);
+		git_config_set_in_file_or_die(opts_file, "options.mainline", buf.buf);
 		strbuf_release(&buf);
 	}
 	if (opts->strategy)
-		git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
+		git_config_set_in_file_or_die(opts_file, "options.strategy", opts->strategy);
 	if (opts->gpg_sign)
-		git_config_set_in_file(opts_file, "options.gpg-sign", opts->gpg_sign);
+		git_config_set_in_file_or_die(opts_file, "options.gpg-sign", opts->gpg_sign);
 	if (opts->xopts) {
 		int i;
 		for (i = 0; i < opts->xopts_nr; i++)
-			git_config_set_multivar_in_file(opts_file,
-							"options.strategy-option",
-							opts->xopts[i], "^$", 0);
+			git_config_set_multivar_in_file_or_die(opts_file,
+							       "options.strategy-option",
+							       opts->xopts[i], "^$", 0);
 	}
 }