drive: make sure invalid auth for teamdrives always reports an error

For some reason Google doesn't return an error if you use a service
account with the wrong permissions to list a team drive.  This gives
the user the false impression that the drive is empty.

This change:
- calls teamdrives get on rclone about
- calls teamdrives get on a listing of the root which returned no entries

These will both detect a team drive which has the incorrect auth and
workaround the issue.

Fixes: #3763
See: https://forum.rclone.org/t/rclone-missing-error-code-when-sas-have-no-permission/13086
See: https://forum.rclone.org/t/need-need-bug-verification-rclone-about-doesnt-work-on-teamdrives-empty-output/13105

backend/drive/drive.go

@@ -1480,6 +1480,14 @@ func (f *Fs) List(ctx context.Context, dir string) (entries fs.DirEntries, err e
 	if iErr != nil {
 		return nil, iErr
 	}
+	// If listing the root of a teamdrive and got no entries,
+	// double check we have access
+	if f.isTeamDrive && len(entries) == 0 && f.root == "" && dir == "" {
+		err = f.teamDriveOK(ctx)
+		if err != nil {
+			return nil, err
+		}
+	}
 	return entries, nil
 }
 
@@ -1617,6 +1625,7 @@ func (f *Fs) ListR(ctx context.Context, dir string, callback fs.ListRCallback) (
 	out := make(chan error, fs.Config.Checkers)
 	list := walk.NewListRHelper(callback)
 	overflow := []listREntry{}
+	listed := 0
 
 	cb := func(entry fs.DirEntry) error {
 		mu.Lock()
@@ -1629,6 +1638,7 @@ func (f *Fs) ListR(ctx context.Context, dir string, callback fs.ListRCallback) (
 				overflow = append(overflow, listREntry{d.ID(), d.Remote()})
 			}
 		}
+		listed++
 		return list.Add(entry)
 	}
 
@@ -1685,7 +1695,21 @@ func (f *Fs) ListR(ctx context.Context, dir string, callback fs.ListRCallback) (
 		return err
 	}
 
-	return list.Flush()
+	err = list.Flush()
+	if err != nil {
+		return err
+	}
+
+	// If listing the root of a teamdrive and got no entries,
+	// double check we have access
+	if f.isTeamDrive && listed == 0 && f.root == "" && dir == "" {
+		err = f.teamDriveOK(ctx)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
 // itemToDirEntry converts a drive.File to a fs.DirEntry.
@@ -2058,9 +2082,30 @@ func (f *Fs) CleanUp(ctx context.Context) error {
 	return nil
 }
 
+// teamDriveOK checks to see if we can access the team drive
+func (f *Fs) teamDriveOK(ctx context.Context) (err error) {
+	if !f.isTeamDrive {
+		return nil
+	}
+	var td *drive.Drive
+	err = f.pacer.Call(func() (bool, error) {
+		td, err = f.svc.Drives.Get(f.opt.TeamDriveID).Fields("name,id,capabilities,createdTime,restrictions").Context(ctx).Do()
+		return shouldRetry(err)
+	})
+	if err != nil {
+		return errors.Wrap(err, "failed to get Team/Shared Drive info")
+	}
+	fs.Debugf(f, "read info from team drive %q", td.Name)
+	return err
+}
+
 // About gets quota information
 func (f *Fs) About(ctx context.Context) (*fs.Usage, error) {
 	if f.isTeamDrive {
+		err := f.teamDriveOK(ctx)
+		if err != nil {
+			return nil, err
+		}
 		// Teamdrives don't appear to have a usage API so just return empty
 		return &fs.Usage{}, nil
 	}