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