core: Implement Walk directory listing and use in place of Lister

This is in preparation for removing the Lister code and replacing the
fundamental operation in the Fs with listing a single directory.

cmd/all/all.go

@@ -20,6 +20,7 @@ import (
 	_ "github.com/ncw/rclone/cmd/gendocs"
 	_ "github.com/ncw/rclone/cmd/listremotes"
 	_ "github.com/ncw/rclone/cmd/ls"
+	_ "github.com/ncw/rclone/cmd/ls2"
 	_ "github.com/ncw/rclone/cmd/lsd"
 	_ "github.com/ncw/rclone/cmd/lsl"
 	_ "github.com/ncw/rclone/cmd/md5sum"

cmd/ls2/ls2.go

@@ -0,0 +1,46 @@
+package ls2
+
+import (
+	"fmt"
+
+	"github.com/ncw/rclone/cmd"
+	"github.com/ncw/rclone/fs"
+	"github.com/spf13/cobra"
+)
+
+var (
+	recurse bool
+)
+
+func init() {
+	cmd.Root.AddCommand(commandDefintion)
+	commandDefintion.Flags().BoolVarP(&recurse, "recursive", "R", false, "Recurse into the listing.")
+}
+
+var commandDefintion = &cobra.Command{
+	Use:    "ls2 remote:path",
+	Short:  `List directories and objects in the path.`,
+	Hidden: true,
+	Run: func(command *cobra.Command, args []string) {
+		cmd.CheckArgs(1, 1, command, args)
+		fsrc := cmd.NewFsSrc(args)
+		cmd.Run(false, false, command, func() error {
+			return fs.Walk(fsrc, "", false, fs.ConfigMaxDepth(recurse), func(path string, entries fs.DirEntries, err error) error {
+				if err != nil {
+					fs.Stats.Error()
+					fs.Errorf(path, "error listing: %v", err)
+					return nil
+				}
+				for _, entry := range entries {
+					_, isDir := entry.(*fs.Dir)
+					if isDir {
+						fmt.Println(entry.Remote() + "/")
+					} else {
+						fmt.Println(entry.Remote())
+					}
+				}
+				return nil
+			})
+		})
+	},
+}

cmd/mountlib/mounttest/fs.go

@@ -240,7 +240,7 @@ func (r *Run) readLocal(t *testing.T, dir dirMap, filepath string) {
 
 // reads the remote tree into dir
 func (r *Run) readRemote(t *testing.T, dir dirMap, filepath string) {
-	objs, dirs, err := fs.NewLister().SetLevel(1).Start(r.fremote, filepath).GetAll()
+	objs, dirs, err := fs.WalkGetAll(r.fremote, filepath, true, 1)
 	if err == fs.ErrorDirNotFound {
 		return
 	}