rebase -i: use struct commit when parsing options

This is in preparation for using `struct rebase_options` when parsing
options in cmd_rebase__interactive(). Using a string for onto,
restrict_revision and upstream, was a hangover from the scripted version
of rebase. The functions that use these variables are updated to take a
`struct commit`.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/parse-options-cb.c b/parse-options-cb.c
index 2733393546..2206eb763c 100644
--- a/parse-options-cb.c
+++ b/parse-options-cb.c
@@ -96,6 +96,23 @@ int parse_opt_commits(const struct option *opt, const char *arg, int unset)
 	return 0;
 }
 
+int parse_opt_commit(const struct option *opt, const char *arg, int unset)
+{
+	struct object_id oid;
+	struct commit *commit;
+	struct commit **target = opt->value;
+
+	if (!arg)
+		return -1;
+	if (get_oid(arg, &oid))
+		return error("malformed object name %s", arg);
+	commit = lookup_commit_reference(the_repository, &oid);
+	if (!commit)
+		return error("no such commit %s", arg);
+	*target = commit;
+	return 0;
+}
+
 int parse_opt_object_name(const struct option *opt, const char *arg, int unset)
 {
 	struct object_id oid;