odin-js-fundamentals-part-4/node_modules/es-abstract/2021/Canonicalize.js

56 lines
1.2 KiB
JavaScript

'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var callBound = require('call-bind/callBound');
var has = require('has');
var $charCodeAt = callBound('String.prototype.charCodeAt');
var $toUpperCase = callBound('String.prototype.toUpperCase');
var Type = require('./Type');
var caseFolding = require('../helpers/caseFolding');
// https://262.ecma-international.org/6.0/#sec-runtime-semantics-canonicalize-ch
module.exports = function Canonicalize(ch, IgnoreCase, Unicode) {
if (Type(ch) !== 'String') {
throw new $TypeError('Assertion failed: `ch` must be a character');
}
if (Type(IgnoreCase) !== 'Boolean' || Type(Unicode) !== 'Boolean') {
throw new $TypeError('Assertion failed: `IgnoreCase` and `Unicode` must be Booleans');
}
if (!IgnoreCase) {
return ch; // step 1
}
if (Unicode) { // step 2
if (has(caseFolding.C, ch)) {
return caseFolding.C[ch];
}
if (has(caseFolding.S, ch)) {
return caseFolding.S[ch];
}
return ch; // step 2.b
}
var u = $toUpperCase(ch); // step 2
if (u.length !== 1) {
return ch; // step 3
}
var cu = u; // step 4
if ($charCodeAt(ch, 0) >= 128 && $charCodeAt(cu, 0) < 128) {
return ch; // step 5
}
return cu;
};