+sub ffq_prev_info () {
+ # => ($ffq_prev, $gdrlast, $ffq_prev_commitish)
+ my ($status, $message, $current, $ffq_prev, $gdrlast)
+ = ffq_prev_branchinfo();
+ if ($status ne 'branch') {
+ snag $status, "could not check ffq-prev: $message";
+ snags_maybe_bail();
+ }
+ my $ffq_prev_commitish = $ffq_prev && git_get_ref $ffq_prev;
+ return ($ffq_prev, $gdrlast, $ffq_prev_commitish);
+}
+
+sub stitch ($$$$$) {
+ my ($old_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose) = @_;
+
+ push @deferred_updates, "delete $ffq_prev $ffq_prev_commitish";
+
+ if (is_fast_fwd $old_head, $ffq_prev_commitish) {
+ my $differs = get_differs $old_head, $ffq_prev_commitish;
+ unless ($differs & ~D_PAT_ADD) {
+ # ffq-prev is ahead of us, and the only tree changes it has
+ # are possibly addition of things in debian/patches/.
+ # Just wind forwards rather than making a pointless pseudomerge.
+ push @deferred_updates,
+ "update $gdrlast $ffq_prev_commitish $git_null_obj";
+ update_head_checkout $old_head, $ffq_prev_commitish,
+ "stitch (fast forward)";
+ return;
+ }
+ }
+ fresh_workarea();
+ # We make pseudomerges with L as the contributing parent.
+ # This makes git rev-list --first-parent work properly.
+ my $new_head = make_commit [ $old_head, $ffq_prev ], [
+ 'Declare fast forward / record previous work',
+ "[git-debrebase pseudomerge: $prose]",
+ ];
+ push @deferred_updates, "update $gdrlast $new_head $git_null_obj";
+ update_head $old_head, $new_head, "stitch: $prose";
+}
+
+sub do_stitch ($;$) {
+ my ($prose, $unclean) = @_;
+
+ my ($ffq_prev, $gdrlast, $ffq_prev_commitish) = ffq_prev_info();
+ if (!$ffq_prev_commitish) {
+ fail "No ffq-prev to stitch." unless $opt_noop_ok;
+ return;
+ }
+ my $dangling_head = get_head();
+
+ keycommits $dangling_head, $unclean,$unclean,$unclean;
+ snags_maybe_bail();
+
+ stitch($dangling_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose);
+}
+
+sub cmd_new_upstream () {