Replacements for path-root / path-root-regex

path-root returns the root of a path, / for an absolute path and an empty string for a relative one. path-root-regex is the regular expression behind it, and is only ever pulled in as a dependency of path-root.

In Node.js

parse already exposes this as its root property.

import pathRoot from 'path-root'
import { parse } from 'node:path'

pathRoot(filepath) 
parse(filepath).root 

parse follows the platform it runs on, so on Linux and macOS it reads \ and C: as ordinary filename characters where path-root treated them as roots, and it reads a leading // as a plain root rather than a UNC server and share. Reach for win32.parse if you actually need to parse Windows paths on a POSIX host.

In the browser

node:path is not available, so keep the regular expression. This is the one path-root-regex returns.

import pathRootRegex from 'path-root-regex'
const ROOT_RE = /^([a-zA-Z]:|[\\/]{2}[^\\/]+[\\/]+[^\\/]+)?([\\/])?/

const pathRoot = (filepath) => { 
  if (typeof filepath !== 'string') throw new TypeError('expected a string') 
  return ROOT_RE.exec(filepath)[0] 
} 

Keep the type check. Without it the regex coerces its argument, so a non-string returns an empty string instead of throwing the way path-root does.