37 lines
649 B
JavaScript
37 lines
649 B
JavaScript
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'use strict';
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const stripAnsi = require('strip-ansi');
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const isFullwidthCodePoint = require('is-fullwidth-code-point');
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module.exports = str => {
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if (typeof str !== 'string' || str.length === 0) {
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return 0;
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}
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str = stripAnsi(str);
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let width = 0;
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for (let i = 0; i < str.length; i++) {
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const code = str.codePointAt(i);
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// Ignore control characters
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if (code <= 0x1F || (code >= 0x7F && code <= 0x9F)) {
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continue;
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}
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// Ignore combining characters
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if (code >= 0x300 && code <= 0x36F) {
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continue;
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}
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// Surrogates
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if (code > 0xFFFF) {
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i++;
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}
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width += isFullwidthCodePoint(code) ? 2 : 1;
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}
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return width;
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};
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