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/* Copyright (c) 2014, Yahoo! Inc. All rights reserved. Copyrights licensed under the New BSD License. See the accompanying LICENSE file for terms. */
'use strict';
var randomBytes = require('randombytes');
// Generate an internal UID to make the regexp pattern harder to guess.
var UID_LENGTH = 16; var UID = generateUID(); var PLACE_HOLDER_REGEXP = new RegExp('(\\\\)?"@__(F|R|D|M|S|A|U|I|B)-' + UID + '-(\\d+)__@"', 'g');
var IS_NATIVE_CODE_REGEXP = /\{\s*\[native code\]\s*\}/g; var IS_PURE_FUNCTION = /function.*?\(/; var IS_ARROW_FUNCTION = /.*?=>.*?/; var UNSAFE_CHARS_REGEXP = /[<>\/\u2028\u2029]/g;
var RESERVED_SYMBOLS = ['*', 'async'];
// Mapping of unsafe HTML and invalid JavaScript line terminator chars to their
// Unicode char counterparts which are safe to use in JavaScript strings.
var ESCAPED_CHARS = { '<' : '\\u003C', '>' : '\\u003E', '/' : '\\u002F', '\u2028': '\\u2028', '\u2029': '\\u2029' };
function escapeUnsafeChars(unsafeChar) { return ESCAPED_CHARS[unsafeChar]; }
function generateUID() { var bytes = randomBytes(UID_LENGTH); var result = ''; for(var i=0; i<UID_LENGTH; ++i) { result += bytes[i].toString(16); } return result; }
function deleteFunctions(obj){ var functionKeys = []; for (var key in obj) { if (typeof obj[key] === "function") { functionKeys.push(key); } } for (var i = 0; i < functionKeys.length; i++) { delete obj[functionKeys[i]]; } }
module.exports = function serialize(obj, options) { options || (options = {});
// Backwards-compatibility for `space` as the second argument.
if (typeof options === 'number' || typeof options === 'string') { options = {space: options}; }
var functions = []; var regexps = []; var dates = []; var maps = []; var sets = []; var arrays = []; var undefs = []; var infinities= []; var bigInts = [];
// Returns placeholders for functions and regexps (identified by index)
// which are later replaced by their string representation.
function replacer(key, value) {
// For nested function
if(options.ignoreFunction){ deleteFunctions(value); }
if (!value && value !== undefined) { return value; }
// If the value is an object w/ a toJSON method, toJSON is called before
// the replacer runs, so we use this[key] to get the non-toJSONed value.
var origValue = this[key]; var type = typeof origValue;
if (type === 'object') { if(origValue instanceof RegExp) { return '@__R-' + UID + '-' + (regexps.push(origValue) - 1) + '__@'; }
if(origValue instanceof Date) { return '@__D-' + UID + '-' + (dates.push(origValue) - 1) + '__@'; }
if(origValue instanceof Map) { return '@__M-' + UID + '-' + (maps.push(origValue) - 1) + '__@'; }
if(origValue instanceof Set) { return '@__S-' + UID + '-' + (sets.push(origValue) - 1) + '__@'; }
if(origValue instanceof Array) { var isSparse = origValue.filter(function(){return true}).length !== origValue.length; if (isSparse) { return '@__A-' + UID + '-' + (arrays.push(origValue) - 1) + '__@'; } } }
if (type === 'function') { return '@__F-' + UID + '-' + (functions.push(origValue) - 1) + '__@'; }
if (type === 'undefined') { return '@__U-' + UID + '-' + (undefs.push(origValue) - 1) + '__@'; }
if (type === 'number' && !isNaN(origValue) && !isFinite(origValue)) { return '@__I-' + UID + '-' + (infinities.push(origValue) - 1) + '__@'; }
if (type === 'bigint') { return '@__B-' + UID + '-' + (bigInts.push(origValue) - 1) + '__@'; }
return value; }
function serializeFunc(fn) { var serializedFn = fn.toString(); if (IS_NATIVE_CODE_REGEXP.test(serializedFn)) { throw new TypeError('Serializing native function: ' + fn.name); }
// pure functions, example: {key: function() {}}
if(IS_PURE_FUNCTION.test(serializedFn)) { return serializedFn; }
// arrow functions, example: arg1 => arg1+5
if(IS_ARROW_FUNCTION.test(serializedFn)) { return serializedFn; }
var argsStartsAt = serializedFn.indexOf('('); var def = serializedFn.substr(0, argsStartsAt) .trim() .split(' ') .filter(function(val) { return val.length > 0 });
var nonReservedSymbols = def.filter(function(val) { return RESERVED_SYMBOLS.indexOf(val) === -1 });
// enhanced literal objects, example: {key() {}}
if(nonReservedSymbols.length > 0) { return (def.indexOf('async') > -1 ? 'async ' : '') + 'function' + (def.join('').indexOf('*') > -1 ? '*' : '') + serializedFn.substr(argsStartsAt); }
// arrow functions
return serializedFn; }
// Check if the parameter is function
if (options.ignoreFunction && typeof obj === "function") { obj = undefined; } // Protects against `JSON.stringify()` returning `undefined`, by serializing
// to the literal string: "undefined".
if (obj === undefined) { return String(obj); }
var str;
// Creates a JSON string representation of the value.
// NOTE: Node 0.12 goes into slow mode with extra JSON.stringify() args.
if (options.isJSON && !options.space) { str = JSON.stringify(obj); } else { str = JSON.stringify(obj, options.isJSON ? null : replacer, options.space); }
// Protects against `JSON.stringify()` returning `undefined`, by serializing
// to the literal string: "undefined".
if (typeof str !== 'string') { return String(str); }
// Replace unsafe HTML and invalid JavaScript line terminator chars with
// their safe Unicode char counterpart. This _must_ happen before the
// regexps and functions are serialized and added back to the string.
if (options.unsafe !== true) { str = str.replace(UNSAFE_CHARS_REGEXP, escapeUnsafeChars); }
if (functions.length === 0 && regexps.length === 0 && dates.length === 0 && maps.length === 0 && sets.length === 0 && arrays.length === 0 && undefs.length === 0 && infinities.length === 0 && bigInts.length === 0) { return str; }
// Replaces all occurrences of function, regexp, date, map and set placeholders in the
// JSON string with their string representations. If the original value can
// not be found, then `undefined` is used.
return str.replace(PLACE_HOLDER_REGEXP, function (match, backSlash, type, valueIndex) { // The placeholder may not be preceded by a backslash. This is to prevent
// replacing things like `"a\"@__R-<UID>-0__@"` and thus outputting
// invalid JS.
if (backSlash) { return match; }
if (type === 'D') { return "new Date(\"" + dates[valueIndex].toISOString() + "\")"; }
if (type === 'R') { return "new RegExp(" + serialize(regexps[valueIndex].source) + ", \"" + regexps[valueIndex].flags + "\")"; }
if (type === 'M') { return "new Map(" + serialize(Array.from(maps[valueIndex].entries()), options) + ")"; }
if (type === 'S') { return "new Set(" + serialize(Array.from(sets[valueIndex].values()), options) + ")"; }
if (type === 'A') { return "Array.prototype.slice.call(" + serialize(Object.assign({ length: arrays[valueIndex].length }, arrays[valueIndex]), options) + ")"; }
if (type === 'U') { return 'undefined' }
if (type === 'I') { return infinities[valueIndex]; }
if (type === 'B') { return "BigInt(\"" + bigInts[valueIndex] + "\")"; }
var fn = functions[valueIndex];
return serializeFunc(fn); }); }
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