JSON.parse只是对象的一部分

Question

我试图解析从服务器返回的以下JSON：

{
"plant_1":{
    "name":"agi_1",
    "growth":[{"d":0,"m":20,"w":2,"n":"10"}]},
"plant_2":{
    "name":"agi_2",
    "growth":[{"d":0,"m":20,"w":2,"n":"20"}]},
"plant_3":{
    "name":"agi_3",
    "growth":[{"d":0,"m":20,"w":2,"n":"30"}]},
"plant_4":{
    "name":"agi_4",
    "growth":[{"d":0,"m":20,"w":2,"n":"40"}]},
"plant_5":{
    "name":"agi_5",
    "growth":[{"d":0,"m":20,"w":2,"n":"50"}]}
}

（为便于阅读而格式化的代码，没有新行字符）

直接解析JSON会返回以下对象：

如您所见，plant_1.growth为空，而其他人在数组中有相应的对象。

复制上述字符串并对字符串执行JSON.parse（例如JSON.parse('string')）可以正常工作并返回正确的模型。

我不知道发生了什么，因为JSON是有效的。知道如何正确恢复模型吗？

编辑1

我使用Express服务器和Mongoskin查询Mongo数据库并返回请求的数据。以下是数据库查询代码：

db.collection('plants').find({owner : owner}, function(err, result) {
    if(err) throw err;

    var idx = 1;
    result.each(function(err, doc) {

        if(doc != null) {

            obj['plant_' + idx] = {
                name : doc.name,
                growth : doc.growth 
            }

            idx = idx + 1;

        } else {

            console.log(JSON.stringify(obj));
            res.send(JSON.stringify(obj));

        }

    });

});

console.log(JSON.stringify(obj))：

的结果

{"plant_1":{"name":"agi_1","growth":[{"d":0,"m":20,"w":2,"n":"10"}]},"plant_2":{"name":"agi_2","growth":[{"d":0,"m":20,"w":2,"n":"20"}]},"plant_3":{"name":"agi_3","growth":[{"d":0,"m":20,"w":2,"n":"30"}]},"plant_4":{"name":"agi_4","growth":[{"d":0,"m":20,"w":2,"n":"40"}]},"plant_5":{"name":"agi_5","growth":[{"d":0,"m":20,"w":2,"n":"50"}]}}

编辑2

用于请求和处理请求的代码

    // Get plants data synchronously
var conn = new XMLHttpRequest();
conn.open("POST", "get-plants", false);

conn.setRequestHeader("Content-type", "application/json");
conn.onreadystatechange = function() {

    console.log(conn.responseText)   // Line 53
    var response = JSON.parse(conn.responseText);
    console.log(response);          // Line 55

    if(conn.readyState == 4 && conn.status == 200) { 

        if(response != null) {

            thatGame.plants = response;

        } else {
            // empty
            console.log('invalid');
        }
    }

};  
conn.send(JSON.stringify({owner : game.state.states['Main'].user}));

console.log(this.plants.plant_1);    // Line 74

浏览器console的屏幕截图。