52 lines
1.2 KiB
JavaScript
52 lines
1.2 KiB
JavaScript
'use strict';
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var $TypeError = require('es-errors/type');
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var callBound = require('call-bind/callBound');
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var hasOwn = require('hasown');
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var $charCodeAt = callBound('String.prototype.charCodeAt');
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var $toUpperCase = callBound('String.prototype.toUpperCase');
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var caseFolding = require('../helpers/caseFolding.json');
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// https://262.ecma-international.org/6.0/#sec-runtime-semantics-canonicalize-ch
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module.exports = function Canonicalize(ch, IgnoreCase, Unicode) {
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if (typeof ch !== 'string') {
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throw new $TypeError('Assertion failed: `ch` must be a character');
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}
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if (typeof IgnoreCase !== 'boolean' || typeof Unicode !== 'boolean') {
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throw new $TypeError('Assertion failed: `IgnoreCase` and `Unicode` must be Booleans');
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}
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if (!IgnoreCase) {
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return ch; // step 1
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}
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if (Unicode) { // step 2
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if (hasOwn(caseFolding.C, ch)) {
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return caseFolding.C[ch];
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}
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if (hasOwn(caseFolding.S, ch)) {
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return caseFolding.S[ch];
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}
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return ch; // step 2.b
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}
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var u = $toUpperCase(ch); // step 2
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if (u.length !== 1) {
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return ch; // step 3
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}
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var cu = u; // step 4
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if ($charCodeAt(ch, 0) >= 128 && $charCodeAt(cu, 0) < 128) {
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return ch; // step 5
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}
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return cu;
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};
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