revert: Save command-line options for continuing operation

In the same spirit as ".git/sequencer/head" and ".git/sequencer/todo",
introduce ".git/sequencer/opts" to persist the replay_opts structure
for continuing after a conflict resolution.  Use the gitconfig format
for this file so that it looks like:

  [options]
	  signoff = true
	  record-origin = true
	  mainline = 1
	  strategy = recursive
	  strategy-option = patience
	  strategy-option = ours

Helped-by: Jonathan Nieder <jrnieder@gmail.com>
Helped-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/revert.c

@@ -64,6 +64,7 @@ struct replay_opts {
 #define SEQ_DIR         "sequencer"
 #define SEQ_HEAD_FILE   "sequencer/head"
 #define SEQ_TODO_FILE   "sequencer/todo"
+#define SEQ_OPTS_FILE   "sequencer/opts"
 
 static const char *action_name(const struct replay_opts *opts)
 {
@@ -695,6 +696,37 @@ static void save_todo(struct commit_list *todo_list, struct replay_opts *opts)
 	strbuf_release(&buf);
 }
 
+static void save_opts(struct replay_opts *opts)
+{
+	const char *opts_file = git_path(SEQ_OPTS_FILE);
+
+	if (opts->no_commit)
+		git_config_set_in_file(opts_file, "options.no-commit", "true");
+	if (opts->edit)
+		git_config_set_in_file(opts_file, "options.edit", "true");
+	if (opts->signoff)
+		git_config_set_in_file(opts_file, "options.signoff", "true");
+	if (opts->record_origin)
+		git_config_set_in_file(opts_file, "options.record-origin", "true");
+	if (opts->allow_ff)
+		git_config_set_in_file(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);
+		strbuf_release(&buf);
+	}
+	if (opts->strategy)
+		git_config_set_in_file(opts_file, "options.strategy", opts->strategy);
+	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);
+	}
+}
+
 static int pick_commits(struct replay_opts *opts)
 {
 	struct commit_list *todo_list = NULL;
@@ -717,6 +749,7 @@ static int pick_commits(struct replay_opts *opts)
 		die(_("Can't cherry-pick into empty head"));
 	}
 	save_head(sha1_to_hex(sha1));
+	save_opts(opts);
 
 	for (cur = todo_list; cur; cur = cur->next) {
 		save_todo(cur, opts);

t/t3510-cherry-pick-sequence.sh

@@ -33,10 +33,35 @@ test_expect_success setup '
 
 test_expect_success 'cherry-pick persists data on failure' '
 	pristine_detach initial &&
-	test_must_fail git cherry-pick base..anotherpick &&
+	test_must_fail git cherry-pick -s base..anotherpick &&
 	test_path_is_dir .git/sequencer &&
 	test_path_is_file .git/sequencer/head &&
-	test_path_is_file .git/sequencer/todo
+	test_path_is_file .git/sequencer/todo &&
+	test_path_is_file .git/sequencer/opts
+'
+
+test_expect_success 'cherry-pick persists opts correctly' '
+	pristine_detach initial &&
+	test_must_fail git cherry-pick -s -m 1 --strategy=recursive -X patience -X ours base..anotherpick &&
+	test_path_is_dir .git/sequencer &&
+	test_path_is_file .git/sequencer/head &&
+	test_path_is_file .git/sequencer/todo &&
+	test_path_is_file .git/sequencer/opts &&
+	echo "true" >expect &&
+	git config --file=.git/sequencer/opts --get-all options.signoff >actual &&
+	test_cmp expect actual &&
+	echo "1" >expect &&
+	git config --file=.git/sequencer/opts --get-all options.mainline >actual &&
+	test_cmp expect actual &&
+	echo "recursive" >expect &&
+	git config --file=.git/sequencer/opts --get-all options.strategy >actual &&
+	test_cmp expect actual &&
+	cat >expect <<-\EOF &&
+	patience
+	ours
+	EOF
+	git config --file=.git/sequencer/opts --get-all options.strategy-option >actual &&
+	test_cmp expect actual
 '
 
 test_expect_success 'cherry-pick cleans up sequencer state upon success' '