webpack/lib/util/parseJson.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
*/

"use strict";

const JSONParseError = require("../errors/JSONParseError");

/** @typedef {import("../util/fs").JsonValue} JsonValue */

// Inspired by https://github.com/npm/json-parse-even-better-errors

// Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)
// because the buffer-to-string conversion in `fs.readFileSync()`
// translates it to FEFF, the UTF-16 BOM.
/**
 * @param {string | Buffer} txt text
 * @returns {string} text without BOM
 */
const stripBOM = (txt) => String(txt).replace(/^\uFEFF/, "");

/**
 * @template [R=JsonValue]
 * @callback ParseJsonFn
 * @param {string} raw text
 * @param {(this: EXPECTED_ANY, key: string, value: EXPECTED_ANY) => EXPECTED_ANY=} reviver reviver
 * @returns {R} parsed JSON
 */

/** @type {ParseJsonFn} */
const parseJson = (raw, reviver) => {
	const txt = stripBOM(raw);

	try {
		return JSON.parse(txt, reviver);
	} catch (err) {
		throw new JSONParseError(/** @type {Error} */ (err), raw, txt);
	}
};

module.exports = parseJson;