谷歌Chrome远程调试协议：无法获得功能范围

Question

我使用Remote debugging protocol为Google Chrome编写自定义调试程序。我的调试器工作正常，除了它无法访问功能范围。我监听Debugger.paused事件，监听器得到CallFrame的数组。我从每个帧获得closure范围，因此我可以获得所有绑定变量及其属性。这些变量中有一些功能。我将带有其中一个功能ID的Runtime.getProperties发布到Chrome并获取其属性。以下是我的回应：

{  
  "result":[  
      {  
        "configurable":false, "enumerable":false,
        "isOwn":true, "name":"length",
        "value":{  
            "description":"0",
            "type":"number",
            "value":0
        },
        "writable":false
      }, {  
        "configurable":false, "enumerable":false,
        "isOwn":true, "name":"name",
        "value":{  
            "type":"string",
            "value":""
        },
        "writable":false
      }, {  
        "configurable":false, "enumerable":false,
        "get":{  
            "className":"Function",
            "description":"function ThrowTypeError() { [native code] }",
            "objectId":"{\"injectedScriptId\":3,\"id\":34}",
            "type":"function"
        },
        "isOwn":true,"name":"arguments",
        "set":{  
            "className":"Function",
            "description":"function ThrowTypeError() { [native code] }",
            "objectId":"{\"injectedScriptId\":3,\"id\":35}",
            "type":"function"
        }
      }, {  
        "configurable":false, "enumerable":false,
        "get":{  
            "className":"Function",
            "description":"function ThrowTypeError() { [native code] }",
            "objectId":"{\"injectedScriptId\":3,\"id\":36}",
            "type":"function"
        },
        "isOwn":true, "name":"caller",
        "set":{  
            "className":"Function",
            "description":"function ThrowTypeError() { [native code] }",
            "objectId":"{\"injectedScriptId\":3,\"id\":37}",
            "type":"function"
        }
      }, {  
        "configurable":false, "enumerable":false,
        "isOwn":true, "name":"prototype",
        "value":{  
            "className":"Object",
            "description":"Object",
            "objectId":"{\"injectedScriptId\":3,\"id\":38}",
            "type":"object"
        },
        "writable":true
      }, {  
        "configurable":true, "enumerable":false,
        "isOwn":true, "name":"__proto__",
        "value":{  
            "className":"Function",
            "description":"function Empty() {}",
            "objectId":"{\"injectedScriptId\":3,\"id\":39}",
            "type":"function"
        },
        "writable":true
      }
  ]
}

如您所见，没有<function scope>属性。但是，当我调试相同的代码并停在同一位置时，我可以打开Closure - ＆gt; $return - ＆gt; <function scope>。我真的需要这个，因为$ return是在其范围内包含绑定变量的回调，所以通过回调闭包链我可以重建堆栈跟踪。