vfs: Implement renaming of directories for backends without DirMove r…

…clone#2539

Previously to this change, backends without the optional interface
DirMove could not rename directories.

This change uses the new operations.DirMove call to implement renaming
directories which will fall back to Move/Copy as necessary.

vfs/dir.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/ncw/rclone/fs"
 	"github.com/ncw/rclone/fs/list"
+	"github.com/ncw/rclone/fs/operations"
 	"github.com/ncw/rclone/fs/walk"
 	"github.com/pkg/errors"
 )
@@ -576,15 +577,15 @@ func (d *Dir) Rename(oldName, newName string, destDir *Dir) error {
 			return err
 		}
 	case fs.Directory:
-		doDirMove := d.f.Features().DirMove
-		if doDirMove == nil {
-			err := errors.Errorf("Fs %q can't rename directories (no DirMove)", d.f)
+		features := d.f.Features()
+		if features.DirMove == nil && features.Move == nil && features.Copy == nil {
+			err := errors.Errorf("Fs %q can't rename directories (no DirMove, Move or Copy)", d.f)
 			fs.Errorf(oldPath, "Dir.Rename error: %v", err)
 			return err
 		}
 		srcRemote := x.Remote()
 		dstRemote := newPath
-		err = doDirMove(d.f, srcRemote, dstRemote)
+		err = operations.DirMove(d.f, srcRemote, dstRemote)
 		if err != nil {
 			fs.Errorf(oldPath, "Dir.Rename error: %v", err)
 			return err