rebase -i: honor --rerere-autoupdate

Interactive rebase was ignoring '--rerere-autoupdate'. Fix this by
reading it appropriate file when restoring the sequencer state for an
interactive rebase and passing '--rerere-autoupdate' to merge and
cherry-pick when rebasing with '--preserve-merges'.

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

git-rebase--interactive.sh

@@ -281,7 +281,7 @@ pick_one () {
 
 	test -d "$rewritten" &&
 		pick_one_preserving_merges "$@" && return
-	output eval git cherry-pick \
+	output eval git cherry-pick $allow_rerere_autoupdate \
 			${gpg_sign_opt:+$(git rev-parse --sq-quote "$gpg_sign_opt")} \
 			"$strategy_args" $empty_args $ff "$@"
 
@@ -393,7 +393,8 @@ pick_one_preserving_merges () {
 			merge_args="--no-log --no-ff"
 			if ! do_with_author output eval \
 			'git merge ${gpg_sign_opt:+"$gpg_sign_opt"} \
-				$merge_args $strategy_args -m "$msg_content" $new_parents'
+				$allow_rerere_autoupdate $merge_args \
+				$strategy_args -m "$msg_content" $new_parents'
 			then
 				printf "%s\n" "$msg_content" > "$GIT_DIR"/MERGE_MSG
 				die_with_patch $sha1 "$(eval_gettext "Error redoing merge \$sha1")"
@@ -401,7 +402,7 @@ pick_one_preserving_merges () {
 			echo "$sha1 $(git rev-parse HEAD^0)" >> "$rewritten_list"
 			;;
 		*)
-			output eval git cherry-pick \
+			output eval git cherry-pick $allow_rerere_autoupdate \
 				${gpg_sign_opt:+$(git rev-parse --sq-quote "$gpg_sign_opt")} \
 				"$strategy_args" "$@" ||
 				die_with_patch $sha1 "$(eval_gettext "Could not pick \$sha1")"

sequencer.c

@@ -127,6 +127,7 @@ static GIT_PATH_FUNC(rebase_path_onto, "rebase-merge/onto")
 static GIT_PATH_FUNC(rebase_path_autostash, "rebase-merge/autostash")
 static GIT_PATH_FUNC(rebase_path_strategy, "rebase-merge/strategy")
 static GIT_PATH_FUNC(rebase_path_strategy_opts, "rebase-merge/strategy_opts")
+static GIT_PATH_FUNC(rebase_path_allow_rerere_autoupdate, "rebase-merge/allow_rerere_autoupdate")
 
 static inline int is_rebase_i(const struct replay_opts *opts)
 {
@@ -1479,6 +1480,15 @@ static int read_populate_opts(struct replay_opts *opts)
 				free(opts->gpg_sign);
 				opts->gpg_sign = xstrdup(buf.buf + 2);
 			}
+			strbuf_reset(&buf);
+		}
+
+		if (read_oneliner(&buf, rebase_path_allow_rerere_autoupdate(), 1)) {
+			if (!strcmp(buf.buf, "--rerere-autoupdate"))
+				opts->allow_rerere_auto = RERERE_AUTOUPDATE;
+			else if (!strcmp(buf.buf, "--no-rerere-autoupdate"))
+				opts->allow_rerere_auto = RERERE_NOAUTOUPDATE;
+			strbuf_reset(&buf);
 		}
 
 		if (file_exists(rebase_path_verbose()))

t/t3418-rebase-continue.sh

@@ -141,5 +141,8 @@ test_rerere_autoupdate () {
 
 test_rerere_autoupdate
 test_rerere_autoupdate -m
+GIT_SEQUENCE_EDITOR=: && export GIT_SEQUENCE_EDITOR
+test_rerere_autoupdate -i
+test_rerere_autoupdate --preserve-merges
 
 test_done