delete: added --rmdirs flag to delete directories as well - fixes #4055

If you supply the --rmdirs flag with delete command,
it will remove all empty directories along with it
leaving the root intact.

cmd/delete/delete.go

@@ -4,12 +4,19 @@ import (
 	"context"
 
 	"github.com/rclone/rclone/cmd"
+	"github.com/rclone/rclone/fs/config/flags"
 	"github.com/rclone/rclone/fs/operations"
 	"github.com/spf13/cobra"
 )
 
+var (
+	rmdirs = false
+)
+
 func init() {
 	cmd.Root.AddCommand(commandDefinition)
+	cmdFlags := commandDefinition.Flags()
+	flags.BoolVarP(cmdFlags, &rmdirs, "rmdirs", "", rmdirs, "rmdirs removes empty directories but leaves root intact")
 }
 
 var commandDefinition = &cobra.Command{
@@ -23,6 +30,8 @@ filters so can be used to selectively delete files.
 alone. If you want to delete a directory and all of its contents use
 ` + "`" + `rclone purge` + "`" + `
 
+If you supply the --rmdirs flag, it will remove all empty directories along with it.
+
 Eg delete all files bigger than 100MBytes
 
 Check what would be deleted first (use either)
@@ -41,7 +50,14 @@ delete all files bigger than 100MBytes.
 		cmd.CheckArgs(1, 1, command, args)
 		fsrc := cmd.NewFsSrc(args)
 		cmd.Run(true, false, command, func() error {
-			return operations.Delete(context.Background(), fsrc)
+			if err := operations.Delete(context.Background(), fsrc); err != nil {
+				return err
+			}
+			if rmdirs {
+				fdst := cmd.NewFsDir(args)
+				return operations.Rmdirs(context.Background(), fdst, "", true)
+			}
+			return nil
 		})
 	},
 }