jQuery ajax:error runs even if the response is OK 200

Question

I have a form which submit a form via AJAX with :remote => true. Looking at the server log and FireBug, I get the response 200 OK and it returns JSON in the form of:

Answer 1

JSON.parse('') throws an error. To me, that is stupid, it should return undefined. I added this code to my app

#HACK JSON.parse('') should return undefined, not throw an error
_parse = JSON.parse
JSON.parse = (str) =>
  unless str == ''
    _parse.apply JSON, arguments

or for u poor people not using coffeescript ( untested )

//HACK JSON.parse('') should return undefined, not throw an error
var _parse = JSON.parse
JSON.parse = function(str) {
  if (str !== '')
    return _parse.apply(JSON, arguments);
  else
    return undefined;
}