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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
var EXPORTED_SYMBOLS = ["CanonicalJSON"];
var CanonicalJSON = {
/**
* Return the canonical JSON form of the passed source, sorting all the object
* keys recursively. Note that this method will cause an infinite loop if
* cycles exist in the source (bug 1265357).
*
* @param source
* The elements to be serialized.
*
* The output will have all unicode chars escaped with the unicode codepoint
* as lowercase hexadecimal.
*
* @usage
* CanonicalJSON.stringify(listOfRecords);
**/
stringify: function stringify(source, jsescFn) {
if (typeof jsescFn != "function") {
const { jsesc } = ChromeUtils.import(
);
jsescFn = jsesc;
}
if (Array.isArray(source)) {
const jsonArray = source.map(x => (typeof x === "undefined" ? null : x));
return (
"[" + jsonArray.map(item => stringify(item, jsescFn)).join(",") + "]"
);
}
if (typeof source === "number") {
if (source === 0) {
return Object.is(source, -0) ? "-0" : "0";
}
}
// Leverage jsesc library, mainly for unicode escaping.
const toJSON = input => jsescFn(input, { lowercaseHex: true, json: true });
if (typeof source !== "object" || source === null) {
return toJSON(source);
}
// Dealing with objects, ordering keys.
const sortedKeys = Object.keys(source).sort();
const lastIndex = sortedKeys.length - 1;
return (
sortedKeys.reduce((serial, key, index) => {
const value = source[key];
// JSON.stringify drops keys with an undefined value.
if (typeof value === "undefined") {
return serial;
}
const jsonValue = value && value.toJSON ? value.toJSON() : value;
const suffix = index !== lastIndex ? "," : "";
const escapedKey = toJSON(key);
return (
serial + escapedKey + ":" + stringify(jsonValue, jsescFn) + suffix
);
}, "{") + "}"
);
},
};