27 lines
708 B
JavaScript
27 lines
708 B
JavaScript
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'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var CodePointAt = require('./CodePointAt');
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var $TypeError = GetIntrinsic('%TypeError%');
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var Type = require('./Type');
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// https://262.ecma-international.org/14.0/#sec-isstringwellformedunicode
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module.exports = function IsStringWellFormedUnicode(string) {
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if (Type(string) !== 'String') {
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throw new $TypeError('Assertion failed: `string` must be a String');
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}
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var len = string.length; // step 1
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var k = 0; // step 2
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while (k < len) { // step 3
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var cp = CodePointAt(string, k); // step 3.a
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if (cp['[[IsUnpairedSurrogate]]']) {
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return false; // step 3.b
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}
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k += cp['[[CodeUnitCount]]']; // step 3.c
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}
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return true; // step 4
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};
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