43 lines
931 B
JavaScript
43 lines
931 B
JavaScript
'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $TypeError = GetIntrinsic('%TypeError%');
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var callBound = require('call-bind/callBound');
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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 Type = require('./Type');
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// https://262.ecma-international.org/5.1/#sec-15.10.2.8
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module.exports = function Canonicalize(ch, IgnoreCase) {
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if (Type(ch) !== 'String' || ch.length !== 1) {
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throw new $TypeError('Assertion failed: `ch` must be a character');
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}
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if (Type(IgnoreCase) !== 'Boolean') {
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throw new $TypeError('Assertion failed: `IgnoreCase` must be a Boolean');
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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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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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