Unknown type undefined

**Current behavior**
Public method: options2 throw error `Unknown type undefined`

**To reproduce**

```
  /**
   * show
   * @public
   * @param options1 options1
   * @param options2 options2
   */
  public show = (options1:{}, options2?: {}) => {
    // pass
  };
```

**Expected behavior**

Public method support optional parameters
