The JSON.stringify() function, as outlined in the ECMAScript 5 and newer editions, utilizes the toJSON() method if available on objects.

One issue arises when using Prototype.js or a similar library that includes an Array.prototype.toJSON() function. In this case, arrays are first converted to strings using Array.prototype.toJSON() before being surrounded by extra quotes by JSON.stringify(), resulting in incorrect formatting.

To resolve this issue, a simple solution (based on Raphael Schweikert's answer) is to:

delete Array.prototype.toJSON

While this may cause some repercussions on libraries relying on a toJSON() property for arrays, it is a minor inconvenience compared to the compatibility issues with ECMAScript 5 standards.

It is important to note that modern browsers efficiently implement the JSON Object defined in ECMAScript 5, making it advisable to adhere to the standard and update existing libraries accordingly.

Here is a potential solution that addresses the issue without impacting other dependencies in Prototype:

let _json_stringify = JSON.stringify;
JSON.stringify = function(value) {
    let _array_tojson = Array.prototype.toJSON;
    delete Array.prototype.toJSON;
    let result = _json_stringify(value);
    Array.prototype.toJSON = _array_tojson;
    return result;
};

This approach resolves the problem relating to the Array toJSON conflict with JSON.stringify while also preserving the unctionality of toJSON for other libraries within Prototype.

Adjusting for better accuracy:

An important section of code to focus on is found within the JSON library from JSON.org (as well as other ECMAScript 5's JSON object implementations):

if (value && typeof value === 'object' &&
  typeof value.toJSON === 'function') {
  value = value.toJSON(key);
}

The issue arises with the Prototype library, which adds a toJSON method to Array. When the JSON object encounters an array value, it triggers the toJSON method in Prototype, resulting in a string representation of the array enclosed in quotes. This leads to unexpected outcomes.

To resolve this, either remove the toJSON method from the Array object or stick to using the JSON library exclusively for proper functionality.

I believe a more efficient approach would be to add this code right after the prototype has finished loading

JSON = JSON || {};

JSON.stringify = function(data) { return data.toJSON(); };

JSON.parse = JSON.parse || function(jsonString) { return jsonString.evalJSON(true); };

By doing this, we make the prototype functionality accessible through standard JSON.stringify() and JSON.parse(), while still retaining support for native JSON.parse() in older browsers.

While I may not be an expert in Prototype, I did come across this information in the documentation:

Object.toJSON({"a":[1,2]})

I am uncertain if this method would encounter the same issue as the current encoding.

You can also explore a more comprehensive guide on utilizing JSON with Prototype.

Here is the snippet of code I utilized to address a similar issue:

function convertToString(data){
      var Lib = window.Library
      if (Lib && Lib.Version < '2.0' &&
          Array.prototype.toJsonString && Object.serializeJson){
              return Object.serializeJson(data)
      }
      return JSON.stringify(data)
}

In this script, we first verify the presence of Library and then check its version. If it's an older version, we use Object.serializeJson (if defined), otherwise we resort to using JSON.stringify() method.

This is my approach to the situation.

let stringifiedMethodCall =  Object.toJSON? Object.toJSON(options.jsonMethodCall) :  JSON.stringify(options.jsonMethodCall);

My proposed approach carefully evaluates the impact of Array.prototype.toJSON on JSON stringify to ensure the seamless functioning of the surrounding code:

let sample = { info: [{greetings: 'universe'}] }, check = {};

if(Array.prototype.toJSON) {
    try {
        check = JSON.parse(JSON.stringify(sample));
        if(!check || sample.info !== check.info) {
            delete Array.prototype.toJSON;
        }
    } catch(error) {
        // their only chance
    }
}

It has been noted by individuals that the issue stems from Prototype.js, particularly versions prior to 1.7. I found myself in a similar predicament where my code needed to function with or without Prototype.js present; thus, simply removing Array.prototype.toJSON was not an option due to uncertainty about its dependencies. In light of this, I devised the following solution:

function safeToJSON(item){ 
    if ([1,2,3] === JSON.parse(JSON.stringify([1,2,3]))){
        return JSON.stringify(item); //desired behavior
    } else { 
        return item.toJSON(); //Prototype.js quirkiness
    }
}

Hopefully, this solution proves beneficial to someone facing a similar dilemma.

If you're looking to avoid causing any harm and want a code that will work smoothly on most browsers, you can achieve it in the following way:

(function (undefined) { // Ensures _json_stringify is contained within this scope and redefines undefined if necessary
  if (true || typeof(Prototype) !== 'undefined') {
    // First step is to ensure access to an object's prototype.
    // Refer to http://stackoverflow.com/questions/7662147/how-to-access-object-prototype-in-javascript
    if(typeof(Object.getPrototypeOf) === 'undefined') {
      if(({}).__proto__ === Object.prototype && ([]).__proto__ === Array.prototype) {
        Object.getPrototypeOf = function getPrototypeOf (object) {
          return object.__proto__;
        };
      } else {
        Object.getPrototypeOf = function getPrototypeOf (object) {
          // May fail if constructor has been altered or removed
          return object.constructor ? object.constructor.prototype : undefined;
        }
      }
    }

    var _json_stringify = JSON.stringify; // Preserves current JSON.stringify functionality
    JSON.stringify = function stringify(obj) {
      var obj_prototype = Object.getPrototypeOf(obj),
          old_json = obj_prototype.toJSON, // Saves the object's toJSON method
          res = null;
      if (old_json) { // If the object has a toJSON method
        obj_prototype.toJSON = undefined;
      }
      res = _json_stringify.apply(this, arguments);
      if (old_json)
        obj_prototype.toJSON = old_json;
      return res;
    };
  }
}.call(this));

Although it may seem intricate, this complexity is necessary to address common use cases effectively. The core concept involves overriding JSON.stringify to eliminate toJSON from the argument object, then invoking the original JSON.stringify, before restoring it.