import { join, sep, parse } from 'path' import fs from 'mz/fs' import glob from 'glob-promise' export default async function resolve (id) { const paths = getPaths(id) for (const p of paths) { if (await isFile(p)) { return p } } const err = new Error(`Cannot find module ${id}`) err.code = 'ENOENT' throw err } export function resolveFromList (id, files) { const paths = getPaths(id) const set = new Set(files) for (const p of paths) { if (set.has(p)) return p } } function getPaths (id) { const i = sep === '/' ? id : id.replace(/\//g, sep) if (i.slice(-3) === '.js') return [i] if (i.slice(-5) === '.json') return [i] if (i[i.length - 1] === sep) { return [ i + 'index.js', i + 'index.json' ] } return [ i + '.js', join(i, 'index.js'), i + '.json', join(i, 'index.json') ] } async function isFile (p) { let stat try { stat = await fs.stat(p) } catch (err) { if (err.code === 'ENOENT') return false throw err } // We need the path to be case sensitive const realpath = await getTrueFilePath(p) if (p !== realpath) return false return stat.isFile() || stat.isFIFO() } // This is based on the stackoverflow answer: http://stackoverflow.com/a/33139702/457224 // We assume we'll get properly normalized path names as p async function getTrueFilePath (p) { let fsPathNormalized = p // OSX: HFS+ stores filenames in NFD (decomposed normal form) Unicode format, // so we must ensure that the input path is in that format first. if (process.platform === 'darwin') fsPathNormalized = fsPathNormalized.normalize('NFD') // !! Windows: Curiously, the drive component mustn't be part of a glob, // !! otherwise glob.sync() will invariably match nothing. // !! Thus, we remove the drive component and instead pass it in as the 'cwd' // !! (working dir.) property below. var pathRoot = parse(fsPathNormalized).root var noDrivePath = fsPathNormalized.slice(Math.max(pathRoot.length - 1, 0)) // Perform case-insensitive globbing (on Windows, relative to the drive / // network share) and return the 1st match, if any. // Fortunately, glob() with nocase case-corrects the input even if it is // a *literal* path. const result = await glob(noDrivePath, { nocase: true, cwd: pathRoot }) return result[0] }