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index.js
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index.js
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import stripAnsi from 'strip-ansi';
import eastAsianWidth from 'eastasianwidth';
import emojiRegex from 'emoji-regex';
export default function stringWidth(string, options = {}) {
if (typeof string !== 'string' || string.length === 0) {
return 0;
}
string = stripAnsi(string);
if (string.length === 0) {
return 0;
}
string = string.replace(emojiRegex(), ' ');
const ambiguousCharWidth = options.ambiguousIsNarrow ? 1 : 2;
let width = 0;
for (let index = 0; index < string.length; index++) {
const codePoint = string.codePointAt(index);
// Ignore control characters
if (codePoint <= 0x1F || (codePoint >= 0x7F && codePoint <= 0x9F)) {
continue;
}
// Ignore combining characters
if (codePoint >= 0x300 && codePoint <= 0x36F) {
continue;
}
const code = eastAsianWidth.eastAsianWidth(string.charAt(index));
switch (code) {
case 'F':
case 'W':
width += 2;
break;
case 'A':
width += ambiguousCharWidth;
break;
default:
width += 1;
}
}
return width;
}