@polkadot/util/cjs/is/hex.js

A collection of useful utilities for @polkadot

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.REGEX_HEX_PREFIXED = exports.REGEX_HEX_NOPREFIX = void 0;
exports.isHex = isHex;
// Copyright 2017-2022 @polkadot/util authors & contributors
// SPDX-License-Identifier: Apache-2.0
const REGEX_HEX_PREFIXED = /^0x[\da-fA-F]+$/;
exports.REGEX_HEX_PREFIXED = REGEX_HEX_PREFIXED;
const REGEX_HEX_NOPREFIX = /^[\da-fA-F]+$/;
/**
 * @name isHex
 * @summary Tests for a hex string.
 * @description
 * Checks to see if the input value is a `0x` prefixed hex string. Optionally (`bitLength` !== -1) checks to see if the bitLength is correct.
 * @example
 * <BR>
 *
 * ```javascript
 * import { isHex } from '@polkadot/util';
 *
 * isHex('0x1234'); // => true
 * isHex('0x1234', 8); // => false
 * ```
 */

exports.REGEX_HEX_NOPREFIX = REGEX_HEX_NOPREFIX;

function isHex(value) {
  let bitLength = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : -1;
  let ignoreLength = arguments.length > 2 ? arguments[2] : undefined;
  return typeof value === 'string' && (value === '0x' || REGEX_HEX_PREFIXED.test(value)) && (bitLength === -1 ? ignoreLength || value.length % 2 === 0 : value.length === 2 + Math.ceil(bitLength / 4));
}