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- 'use strict';
- var $ = require('../internals/export');
- var global = require('../internals/global');
- var uncurryThis = require('../internals/function-uncurry-this');
- var anObjectOrUndefined = require('../internals/an-object-or-undefined');
- var aString = require('../internals/a-string');
- var hasOwn = require('../internals/has-own-property');
- var arrayFromConstructorAndList = require('../internals/array-from-constructor-and-list');
- var base64Map = require('../internals/base64-map');
- var getAlphabetOption = require('../internals/get-alphabet-option');
- var base64Alphabet = base64Map.c2i;
- var base64UrlAlphabet = base64Map.c2iUrl;
- var Uint8Array = global.Uint8Array;
- var SyntaxError = global.SyntaxError;
- var charAt = uncurryThis(''.charAt);
- var replace = uncurryThis(''.replace);
- var stringSlice = uncurryThis(''.slice);
- var push = uncurryThis([].push);
- var SPACES = /[\t\n\f\r ]/g;
- var EXTRA_BITS = 'Extra bits';
- // `Uint8Array.fromBase64` method
- // https://github.com/tc39/proposal-arraybuffer-base64
- if (Uint8Array) $({ target: 'Uint8Array', stat: true, forced: true }, {
- fromBase64: function fromBase64(string /* , options */) {
- aString(string);
- var options = arguments.length > 1 ? anObjectOrUndefined(arguments[1]) : undefined;
- var alphabet = getAlphabetOption(options) === 'base64' ? base64Alphabet : base64UrlAlphabet;
- var strict = options ? !!options.strict : false;
- var input = strict ? string : replace(string, SPACES, '');
- if (input.length % 4 === 0) {
- if (stringSlice(input, -2) === '==') input = stringSlice(input, 0, -2);
- else if (stringSlice(input, -1) === '=') input = stringSlice(input, 0, -1);
- } else if (strict) throw new SyntaxError('Input is not correctly padded');
- var lastChunkSize = input.length % 4;
- switch (lastChunkSize) {
- case 1: throw new SyntaxError('Bad input length');
- case 2: input += 'AA'; break;
- case 3: input += 'A';
- }
- var bytes = [];
- var i = 0;
- var inputLength = input.length;
- var at = function (shift) {
- var chr = charAt(input, i + shift);
- if (!hasOwn(alphabet, chr)) throw new SyntaxError('Bad char in input: "' + chr + '"');
- return alphabet[chr] << (18 - 6 * shift);
- };
- for (; i < inputLength; i += 4) {
- var triplet = at(0) + at(1) + at(2) + at(3);
- push(bytes, (triplet >> 16) & 255, (triplet >> 8) & 255, triplet & 255);
- }
- var byteLength = bytes.length;
- if (lastChunkSize === 2) {
- if (strict && bytes[byteLength - 2] !== 0) throw new SyntaxError(EXTRA_BITS);
- byteLength -= 2;
- } else if (lastChunkSize === 3) {
- if (strict && bytes[byteLength - 1] !== 0) throw new SyntaxError(EXTRA_BITS);
- byteLength--;
- }
- return arrayFromConstructorAndList(Uint8Array, bytes, byteLength);
- }
- });
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