git-debrebase: break out stitch() (nfc)

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

1 files changed, 30 insertions, 22 deletions

diff --git a/git-debrebase b/git-debrebase
index 29f06a3..1713246 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -1026,6 +1026,33 @@ sub record_ffq_auto () {
     }
 }
 
+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();
+    my $new_head = make_commit [ $old_head, $ffq_prev ], [
+	'Declare fast forward / record previous work',
+        "[git-debrebase pseudomerge: stitch$prose]",
+    ];
+    push @deferred_updates, "update $gdrlast $new_head $git_null_obj";
+    update_head $old_head, $new_head, "stitch";
+}
+
 sub cmd_new_upstream_v0 () {
     # automatically and unconditionally launders before rebasing
     # if rebase --abort is used, laundering has still been done
@@ -1246,8 +1273,8 @@ sub cmd_stitch () {
 	fproblem $status, "could not check ffq-prev: $message";
 	fproblems_maybe_bail();
     }
-    my $prev = $ffq_prev && git_get_ref $ffq_prev;
-    if (!$prev) {
+    my $ffq_prev_commitish = $ffq_prev && git_get_ref $ffq_prev;
+    if (!$ffq_prev_commitish) {
 	fail "No ffq-prev to stitch." unless $opt_noop_ok;
 	return;
     }
@@ -1255,26 +1282,7 @@ sub cmd_stitch () {
 
     keycommits $old_head, \&fproblem, \&fproblem, \&fproblem;
 
-    push @deferred_updates, "delete $ffq_prev $prev";
-
-    if (is_fast_fwd $old_head, $prev) {
-	my $differs = get_differs $old_head, $prev;
-	unless ($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 $prev $git_null_obj";
-	    update_head_checkout $old_head, $prev, "stitch (fast forward)";
-	    return;
-	}
-    }
-    fresh_workarea();
-    my $new_head = make_commit [ $old_head, $ffq_prev ], [
-	'Declare fast forward / record previous work',
-        "[git-debrebase pseudomerge: stitch$prose]",
-    ];
-    push @deferred_updates, "update $gdrlast $new_head $git_null_obj";
-    update_head $old_head, $new_head, "stitch";
+    stitch($old_head, $ffq_prev, $gdrlast, $ffq_prev_commitish, $prose);
 }
 
 sub cmd_convert_from_gbp () {