Cursor with undefined result

[kevinprotoss]

Hi,

I made some queries to get documents based on AQL. Some of them will return no error and a cursor like this:

{ extra: undefined,
  _connection: 
   { config: 
      { url: 'http://127.0.0.1:8529',
        databaseName: 'n-fuse',
        arangoVersion: 20300,
        agentOptions: [Object],
        headers: [Object] },
     _request: [Function: request] },
  _api: 
   { _connection: { config: [Object], _request: [Function: request] },
     _path: '_api',
     _headers: undefined },
  _result: undefined,
  _hasMore: false,
  _id: undefined,
  _index: 0 }

First of all, I'm sure the collection and relevant document exists, but no document is found.
Second, even the document doesn't exist, the cursor should not have an undefined result, shouldn't it?
Last but not least, I call cursor.hasNext() to check whether I can advance the cursor or not. My code then hangs on at this step, no error, no returned value, and no exception. I believe it's the reason of undefined result. Even if I put another try/catch block here, I still can not see any exception.

p.s. this case does not occur each time...

Best regards,
Kevin