From 46e43f4bde4a35785b4997b81e86cd19f046b69b Mon Sep 17 00:00:00 2001 From: Minteck Date: Tue, 21 Dec 2021 16:52:28 +0100 Subject: Commit --- src/node_modules/es-abstract/2020/CodePointAt.js | 58 ++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 src/node_modules/es-abstract/2020/CodePointAt.js (limited to 'src/node_modules/es-abstract/2020/CodePointAt.js') diff --git a/src/node_modules/es-abstract/2020/CodePointAt.js b/src/node_modules/es-abstract/2020/CodePointAt.js new file mode 100644 index 0000000..a25f7b3 --- /dev/null +++ b/src/node_modules/es-abstract/2020/CodePointAt.js @@ -0,0 +1,58 @@ +'use strict'; + +var GetIntrinsic = require('../GetIntrinsic'); + +var $TypeError = GetIntrinsic('%TypeError%'); +var callBound = require('../helpers/callBound'); +var isLeadingSurrogate = require('../helpers/isLeadingSurrogate'); +var isTrailingSurrogate = require('../helpers/isTrailingSurrogate'); + +var Type = require('./Type'); +var UTF16DecodeSurrogatePair = require('./UTF16DecodeSurrogatePair'); + +var $charAt = callBound('String.prototype.charAt'); +var $charCodeAt = callBound('String.prototype.charCodeAt'); + +// https://tc39.es/ecma262/2020/#sec-codepointat + +module.exports = function CodePointAt(string, position) { + if (Type(string) !== 'String') { + throw new $TypeError('Assertion failed: `string` must be a String'); + } + var size = string.length; + if (position < 0 || position >= size) { + throw new $TypeError('Assertion failed: `position` must be >= 0, and < the length of `string`'); + } + var first = $charCodeAt(string, position); + var cp = $charAt(string, position); + var firstIsLeading = isLeadingSurrogate(first); + var firstIsTrailing = isTrailingSurrogate(first); + if (!firstIsLeading && !firstIsTrailing) { + return { + '[[CodePoint]]': cp, + '[[CodeUnitCount]]': 1, + '[[IsUnpairedSurrogate]]': false + }; + } + if (firstIsTrailing || (position + 1 === size)) { + return { + '[[CodePoint]]': cp, + '[[CodeUnitCount]]': 1, + '[[IsUnpairedSurrogate]]': true + }; + } + var second = $charCodeAt(string, position + 1); + if (!isTrailingSurrogate(second)) { + return { + '[[CodePoint]]': cp, + '[[CodeUnitCount]]': 1, + '[[IsUnpairedSurrogate]]': true + }; + } + + return { + '[[CodePoint]]': UTF16DecodeSurrogatePair(first, second), + '[[CodeUnitCount]]': 2, + '[[IsUnpairedSurrogate]]': false + }; +}; -- cgit