From b310490fa5976b0f3e7b3ee9e323f88764687a5b Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Sat, 9 Jul 2022 21:17:47 +0100
Subject: [PATCH] union: fix multiple files being uploaded when roots don't
 exist

See: https://forum.rclone.org/t/union-backend-copying-to-all-remotes-while-it-shouldnt/31781
---
 backend/union/union.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/backend/union/union.go b/backend/union/union.go
index fc78e20c3..0e894a50b 100644
--- a/backend/union/union.go
+++ b/backend/union/union.go
@@ -169,7 +169,11 @@ func (f *Fs) mkdir(ctx context.Context, dir string) ([]*upstream.Fs, error) {
 	if err != nil {
 		return nil, err
 	}
-	return upstreams, nil
+	// If created roots then choose one
+	if dir == "" {
+		upstreams, err = f.create(ctx, dir)
+	}
+	return upstreams, err
 }
 
 // Mkdir makes the root directory of the Fs object