var $ = require('../internals/export'); var getBuiltIn = require('../internals/get-built-in'); var uncurryThis = require('../internals/function-uncurry-this'); var fails = require('../internals/fails'); var toString = require('../internals/to-string'); var hasOwn = require('../internals/has-own-property'); var validateArgumentsLength = require('../internals/validate-arguments-length'); var ctoi = require('../internals/base64-map').ctoi; var disallowed = /[^\d+/a-z]/i; var whitespaces = /[\t\n\f\r ]+/g; var finalEq = /[=]+$/; var $atob = getBuiltIn('atob'); var fromCharCode = String.fromCharCode; var charAt = uncurryThis(''.charAt); var replace = uncurryThis(''.replace); var exec = uncurryThis(disallowed.exec); var NO_SPACES_IGNORE = fails(function () { return $atob(' ') !== ''; }); var NO_ENCODING_CHECK = !fails(function () { $atob('a'); }); var NO_ARG_RECEIVING_CHECK = !NO_SPACES_IGNORE && !NO_ENCODING_CHECK && !fails(function () { $atob(); }); var WRONG_ARITY = !NO_SPACES_IGNORE && !NO_ENCODING_CHECK && $atob.length !== 1; // `atob` method // https://html.spec.whatwg.org/multipage/webappapis.html#dom-atob $({ global: true, enumerable: true, forced: NO_SPACES_IGNORE || NO_ENCODING_CHECK || NO_ARG_RECEIVING_CHECK || WRONG_ARITY }, { atob: function atob(data) { validateArgumentsLength(arguments.length, 1); if (NO_ARG_RECEIVING_CHECK || WRONG_ARITY) return $atob(data); var string = replace(toString(data), whitespaces, ''); var output = ''; var position = 0; var bc = 0; var chr, bs; if (string.length % 4 == 0) { string = replace(string, finalEq, ''); } if (string.length % 4 == 1 || exec(disallowed, string)) { throw new (getBuiltIn('DOMException'))('The string is not correctly encoded', 'InvalidCharacterError'); } while (chr = charAt(string, position++)) { if (hasOwn(ctoi, chr)) { bs = bc % 4 ? bs * 64 + ctoi[chr] : ctoi[chr]; if (bc++ % 4) output += fromCharCode(255 & bs >> (-2 * bc & 6)); } } return output; } });