[рони]

wet,

{
  "testName": "Тест",
  "questionsList": {
    "0": {
      "question": "вопрос",
      "answerList": {
        "0": "ответ 1",
        "1": "ответ 2"
      }
    },
    "1": {
      "question": "вопрос 2",
      "answerList": {
        "0": "ответ 3",
        "1": "ответ 4"
      }
    }
  }
}

var testList = {
    testName: "Тест",
    questionsList: {}
};
$(".question").each(function(b, c) {
    var a = {},
        d = $(this).data("question");
    a.question = d;
    a.answerList = {};
    $(".answer", c).each(function(b, c) {
        a.answerList[b] = $(c).data("answer")
    });
    testList.questionsList[b] = a
});