notes/node_modules/string-width/index.js

36 lines
591 B
JavaScript

'use strict';
const stripAnsi = require('strip-ansi');
const isFullwidthCodePoint = require('is-fullwidth-code-point');
module.exports = str => {
if (typeof str !== 'string' || str.length === 0) {
return 0;
}
let width = 0;
str = stripAnsi(str);
for (let i = 0; i < str.length; i++) {
const code = str.codePointAt(i);
// ignore control characters
if (code <= 0x1f || (code >= 0x7f && code <= 0x9f)) {
continue;
}
// surrogates
if (code >= 0x10000) {
i++;
}
if (isFullwidthCodePoint(code)) {
width += 2;
} else {
width++;
}
}
return width;
};