[WIP] Add atob / btoa (#1036)

CHANGELOG.md

@@ -1,5 +1,8 @@
 ## Changelog
 ##### Unreleased
+- Added [Base64 utility methods](https://developer.mozilla.org/en-US/docs/Glossary/Base64):
+  - `atob`
+  - `btoa`
 - Added the proper validation of arguments to some methods from web standards
 - Added Rhino 1.7.14 compat data
 - Added Deno 1.19 compat data mapping

README.md

@@ -159,6 +159,7 @@ queueMicrotask(() => console.log('called as microtask'));
       - [`Reflect` metadata](#reflect-metadata)
   - [Web standards](#web-standards)
     - [`structuredClone`](#structuredclone)
+    - [Base64 utility methods](#base64-utility-methods)
     - [`setTimeout` and `setInterval`](#settimeout-and-setinterval)
     - [`setImmediate`](#setimmediate)
     - [`queueMicrotask`](#queuemicrotask)
@@ -2998,10 +2999,9 @@ function structuredClone(value: Serializable, { transfer?: Sequence<Transferable
 ```
 [*CommonJS entry points:*](#commonjs-api)
 ```js
-core-js/web/structured-clone
 core-js(-pure)/stable|actual|features/structured-clone
 ```
-[*Examples*](t.ly/dBEC):
+[*Examples*](is.gd/RhK7TW):
 ```js
 const structured = [{ a: 42 }];
 const sclone = structuredClone(structured);
@@ -3036,6 +3036,23 @@ structuredClone(new WeakMap()); // => DataCloneError on non-serializable types
 * `ArrayBuffer` instances and many platform types cannot be transferred in most engines since we have no way to polyfill this behavior, however `.transfer` option works for some platform types. I recommend avoiding this option.
 * Some specific platform types can't be cloned in old engines. Mainly it's very specific types or very old engines, but here are some exceptions. For example, we have no sync way to clone `ImageBitmap` in Safari 14.0- or Firefox 83-, so it's recommended to look to the [polyfill source](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.structured-clone.js) if you wanna clone something specific.
 
+#### Base64 utility methods[⬆](#index)
+[Specification](https://html.spec.whatwg.org/multipage/webappapis.html#atob), [MDN](https://developer.mozilla.org/en-US/docs/Glossary/Base64). Modules [`web.atob`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.atob.js), [`web.btoa`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.btoa.js).
+```js
+function atob(data: string): string;
+function btoa(data: string): string;
+```
+[*CommonJS entry points:*](#commonjs-api)
+```js
+core-js(-pure)/stable|actual|features/atob
+core-js(-pure)/stable|actual|features/btoa
+```
+[*Examples*](is.gd/4Nxmzn):
+```js
+btoa('hi, core-js');      // => 'aGksIGNvcmUtanM='
+atob('aGksIGNvcmUtanM='); // => 'hi, core-js'
+```
+
 #### `setTimeout` and `setInterval`[⬆](#index)
 Module [`web.timers`](https://github.com/zloirock/core-js/blob/master/packages/core-js/modules/web.timers.js). Additional arguments fix for IE9-.
 ```js
@@ -3306,7 +3323,7 @@ console.log(iterator.next().value); // 2
 console.log(iterator.next().value); // 3
 console.log(iterator.next().value); // undefined
 
-getIterator({});   // TypeError: [object Object] is not iterable!
+getIterator({}); // TypeError: [object Object] is not iterable!
 
 let method = getIteratorMethod(list);
 console.log(typeof method);         // 'function'

packages/core-js-compat/src/data.mjs

@@ -1818,6 +1818,26 @@ export const data = {
   },
   'esnext.weak-set.of': {
   },
+  'web.atob': {
+    chrome: '34',
+    deno: '1.0',
+    edge: '13',
+    firefox: '27',
+    // https://github.com/nodejs/node/issues/41450
+    // node: '16.0',
+    opera: '10.5',
+    safari: '10.1',
+  },
+  'web.btoa': {
+    chrome: '4',
+    deno: '1.0',
+    firefox: '1',
+    ie: '10',
+    // https://github.com/nodejs/node/issues/41450
+    // node: '16.0',
+    opera: '10.5',
+    safari: '3.0',
+  },
   'web.dom-collections.for-each': {
     chrome: '58',
     deno: '1.0',

packages/core-js-compat/src/modules-by-versions.mjs

@@ -135,4 +135,8 @@ export default {
     'web.dom-exception.to-string-tag',
     'web.structured-clone',
   ],
+  3.21: [
+    'web.atob',
+    'web.btoa',
+  ],
 };

packages/core-js/actual/atob.js

@@ -0,0 +1,3 @@
+var parent = require('../stable/atob');
+
+module.exports = parent;

packages/core-js/actual/btoa.js

@@ -0,0 +1,3 @@
+var parent = require('../stable/btoa');
+
+module.exports = parent;

packages/core-js/features/atob.js

@@ -0,0 +1,3 @@
+var parent = require('../actual/atob');
+
+module.exports = parent;

packages/core-js/features/btoa.js

@@ -0,0 +1,3 @@
+var parent = require('../actual/btoa');
+
+module.exports = parent;

packages/core-js/internals/base64-map.js

@@ -0,0 +1,9 @@
+var itoc = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
+var ctoi = {};
+
+for (var index = 0; index < 66; index++) ctoi[itoc.charAt(index)] = index;
+
+module.exports = {
+  itoc: itoc,
+  ctoi: ctoi
+};

packages/core-js/modules/web.atob.js

@@ -0,0 +1,52 @@
+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_ARG_RECEIVING_CHECK = !NO_SPACES_IGNORE && !fails(function () {
+  $atob();
+});
+
+// `atob` method
+// https://html.spec.whatwg.org/multipage/webappapis.html#dom-atob
+$({ global: true, enumerable: true, forced: NO_SPACES_IGNORE || NO_ARG_RECEIVING_CHECK }, {
+  atob: function atob(data) {
+    validateArgumentsLength(arguments.length, 1);
+    if (NO_ARG_RECEIVING_CHECK) 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;
+  }
+});

packages/core-js/modules/web.btoa.js

@@ -0,0 +1,37 @@
+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 validateArgumentsLength = require('../internals/validate-arguments-length');
+var itoc = require('../internals/base64-map').itoc;
+
+var $btoa = getBuiltIn('btoa');
+var charAt = uncurryThis(''.charAt);
+var charCodeAt = uncurryThis(''.charCodeAt);
+
+var NO_ARG_RECEIVING_CHECK = !!$btoa && !fails(function () {
+  $btoa();
+});
+
+// `btoa` method
+// https://html.spec.whatwg.org/multipage/webappapis.html#dom-btoa
+$({ global: true, enumerable: true, forced: NO_ARG_RECEIVING_CHECK }, {
+  btoa: function btoa(data) {
+    validateArgumentsLength(arguments.length, 1);
+    if (NO_ARG_RECEIVING_CHECK) return $btoa(data);
+    var string = toString(data);
+    var output = '';
+    var position = 0;
+    var map = itoc;
+    var block, charCode;
+    while (charAt(string, position) || (map = '=', position % 1)) {
+      charCode = charCodeAt(string, position += 3 / 4);
+      if (charCode > 0xFF) {
+        throw new (getBuiltIn('DOMException'))('The string contains characters outside of the Latin1 range', 'InvalidCharacterError');
+      }
+      block = block << 8 | charCode;
+      output += charAt(map, 63 & block >> 8 - position % 1 * 8);
+    } return output;
+  }
+});

packages/core-js/stable/atob.js

@@ -0,0 +1,9 @@
+require('../modules/es.error.to-string');
+require('../modules/es.object.to-string');
+require('../modules/web.atob');
+require('../modules/web.dom-exception.constructor');
+require('../modules/web.dom-exception.stack');
+require('../modules/web.dom-exception.to-string-tag');
+var path = require('../internals/path');
+
+module.exports = path.atob;

packages/core-js/stable/btoa.js

@@ -0,0 +1,9 @@
+require('../modules/es.error.to-string');
+require('../modules/es.object.to-string');
+require('../modules/web.btoa');
+require('../modules/web.dom-exception.constructor');
+require('../modules/web.dom-exception.stack');
+require('../modules/web.dom-exception.to-string-tag');
+var path = require('../internals/path');
+
+module.exports = path.btoa;

packages/core-js/web/index.js

@@ -1,3 +1,5 @@
+require('../modules/web.atob');
+require('../modules/web.btoa');
 require('../modules/web.dom-collections.for-each');
 require('../modules/web.dom-collections.iterator');
 require('../modules/web.dom-exception.constructor');

tests/commonjs.mjs

@@ -545,6 +545,8 @@ for (PATH of ['core-js-pure', 'core-js']) {
   }
 
   for (const NS of ['stable', 'actual', 'features']) {
+    ok(load(NS, 'atob')('Zg==') === 'f');
+    ok(load(NS, 'btoa')('f') === 'Zg==');
     ok(typeof load(NS, 'dom-exception/constructor') == 'function');
     ok(load(NS, 'dom-exception/to-string-tag') === 'DOMException');
     ok(typeof load(NS, 'dom-exception') == 'function');

tests/compat/tests.js

@@ -1618,6 +1618,20 @@ GLOBAL.tests = {
   'esnext.weak-set.of': function () {
     return WeakSet.of;
   },
+  'web.atob': function () {
+    try {
+      atob();
+    } catch (error) {
+      return atob(' ') === '';
+    }
+  },
+  'web.btoa': function () {
+    try {
+      btoa();
+    } catch (error) {
+      return typeof btoa == 'function';
+    }
+  },
   'web.dom-collections.for-each': function () {
     return (!GLOBAL.NodeList || (NodeList.prototype.forEach && NodeList.prototype.forEach === [].forEach))
       && (!GLOBAL.DOMTokenList || (DOMTokenList.prototype.forEach && DOMTokenList.prototype.forEach === [].forEach));

tests/pure/web.atob.js

@@ -0,0 +1,33 @@
+// based on https://github.com/davidchambers/Base64.js/blob/master/test/base64.js
+import atob from 'core-js-pure/stable/atob';
+
+QUnit.test('atob', assert => {
+  assert.isFunction(atob);
+  assert.arity(atob, 1);
+
+  assert.same(atob(''), '');
+  assert.same(atob('Zg=='), 'f');
+  assert.same(atob('Zm8='), 'fo');
+  assert.same(atob('Zm9v'), 'foo');
+  assert.same(atob('cXV1eA=='), 'quux');
+  assert.same(atob('ISIjJCU='), '!"#$%');
+  assert.same(atob('JicoKSor'), "&'()*+");
+  assert.same(atob('LC0uLzAxMg=='), ',-./012');
+  assert.same(atob('MzQ1Njc4OTo='), '3456789:');
+  assert.same(atob('Ozw9Pj9AQUJD'), ';<=>?@ABC');
+  assert.same(atob('REVGR0hJSktMTQ=='), 'DEFGHIJKLM');
+  assert.same(atob('Tk9QUVJTVFVWV1g='), 'NOPQRSTUVWX');
+  assert.same(atob('WVpbXF1eX2BhYmM='), 'YZ[\\]^_`abc');
+  assert.same(atob('ZGVmZ2hpamtsbW5vcA=='), 'defghijklmnop');
+  assert.same(atob('cXJzdHV2d3h5ent8fX4='), 'qrstuvwxyz{|}~');
+  assert.same(atob(' '), '');
+
+  assert.same(atob(42), atob('42'));
+  assert.same(atob(null), atob('null'));
+
+  assert.throws(() => atob(), TypeError, 'no args');
+  assert.throws(() => atob('a'), 'invalid #1');
+  assert.throws(() => atob('a '), 'invalid #2');
+  assert.throws(() => atob('aaaaa'), 'invalid #3');
+  assert.throws(() => atob('[object Object]'), 'invalid #4');
+});

tests/pure/web.btoa.js

@@ -0,0 +1,31 @@
+// based on https://github.com/davidchambers/Base64.js/blob/master/test/base64.js
+import btoa from 'core-js-pure/stable/btoa';
+
+QUnit.test('btoa', assert => {
+  assert.isFunction(btoa);
+  assert.arity(btoa, 1);
+
+  assert.same(btoa(''), '');
+  assert.same(btoa('f'), 'Zg==');
+  assert.same(btoa('fo'), 'Zm8=');
+  assert.same(btoa('foo'), 'Zm9v');
+  assert.same(btoa('quux'), 'cXV1eA==');
+  assert.same(btoa('!"#$%'), 'ISIjJCU=');
+  assert.same(btoa("&'()*+"), 'JicoKSor');
+  assert.same(btoa(',-./012'), 'LC0uLzAxMg==');
+  assert.same(btoa('3456789:'), 'MzQ1Njc4OTo=');
+  assert.same(btoa(';<=>?@ABC'), 'Ozw9Pj9AQUJD');
+  assert.same(btoa('DEFGHIJKLM'), 'REVGR0hJSktMTQ==');
+  assert.same(btoa('NOPQRSTUVWX'), 'Tk9QUVJTVFVWV1g=');
+  assert.same(btoa('YZ[\\]^_`abc'), 'WVpbXF1eX2BhYmM=');
+  assert.same(btoa('defghijklmnop'), 'ZGVmZ2hpamtsbW5vcA==');
+  assert.same(btoa('qrstuvwxyz{|}~'), 'cXJzdHV2d3h5ent8fX4=');
+  assert.same(btoa('qrstuvwxyz{|}~'), 'cXJzdHV2d3h5ent8fX4=');
+
+  assert.same(btoa(42), btoa('42'));
+  assert.same(btoa(null), btoa('null'));
+  assert.same(btoa({ x: 1 }), btoa('[object Object]'));
+
+  assert.throws(() => btoa(), TypeError, 'no args');
+  assert.throws(() => btoa('✈'), 'non-ASCII');
+});

tests/tests/web.atob.js

@@ -0,0 +1,35 @@
+// based on https://github.com/davidchambers/Base64.js/blob/master/test/base64.js
+import { NODE } from '../helpers/constants';
+
+QUnit.test('atob', assert => {
+  assert.isFunction(atob);
+  assert.arity(atob, 1);
+  assert.name(atob, 'atob');
+  if (!NODE) assert.looksNative(atob);
+
+  assert.same(atob(''), '');
+  assert.same(atob('Zg=='), 'f');
+  assert.same(atob('Zm8='), 'fo');
+  assert.same(atob('Zm9v'), 'foo');
+  assert.same(atob('cXV1eA=='), 'quux');
+  assert.same(atob('ISIjJCU='), '!"#$%');
+  assert.same(atob('JicoKSor'), "&'()*+");
+  assert.same(atob('LC0uLzAxMg=='), ',-./012');
+  assert.same(atob('MzQ1Njc4OTo='), '3456789:');
+  assert.same(atob('Ozw9Pj9AQUJD'), ';<=>?@ABC');
+  assert.same(atob('REVGR0hJSktMTQ=='), 'DEFGHIJKLM');
+  assert.same(atob('Tk9QUVJTVFVWV1g='), 'NOPQRSTUVWX');
+  assert.same(atob('WVpbXF1eX2BhYmM='), 'YZ[\\]^_`abc');
+  assert.same(atob('ZGVmZ2hpamtsbW5vcA=='), 'defghijklmnop');
+  assert.same(atob('cXJzdHV2d3h5ent8fX4='), 'qrstuvwxyz{|}~');
+  assert.same(atob(' '), '');
+
+  assert.same(atob(42), atob('42'));
+  assert.same(atob(null), atob('null'));
+
+  assert.throws(() => atob(), TypeError, 'no args');
+  assert.throws(() => atob('a'), 'invalid #1');
+  assert.throws(() => atob('a '), 'invalid #2');
+  assert.throws(() => atob('aaaaa'), 'invalid #3');
+  assert.throws(() => atob('[object Object]'), 'invalid #4');
+});