code: func (F *Frisby) ExpectJsonLength(path string, length int) *Frisby {
  	Global.NumAsserts++
  	json, err := F.Resp.Json()
  	if err != nil {
  		F.AddError(err.Error())
  		return F
  	}
  
  	if path != "" {
  		path_items := strings.Split(path, Global.PathSeparator)
  		json = json.GetPath(path_items...)
  	}
  
  	ary, err := json.Array()
  	if err != nil {
  		F.AddError(err.Error())
  		return F
  	}
  	L := len(ary)
  
  	if L != length {
  		err_str := fmt.Sprintf("Expect length to be %d, but got %d", length, L)
  		F.AddError(err_str)
  	}
  
  	return F
  }
docs: // ExpectJsonLength checks if the JSON at path
  // is an array and has the correct length
  //
  // path can be a dot joined field names.
  // ex:  'path.to.subobject.field'