Use yarn's fslib to implement the fake filesystem.

Leverage the work done by yarn, rather than reimplementing from scratch.

This means the fake fs is now reading from a zip file in the binary.

A few methods need custom implementations as the fake fs is not
writable. These were copied and adjusted from the yarn ZipOpenFS.

package.json

@@ -14,7 +14,7 @@
     "lint": "tslint \"{src,plugins,tasks}/**/*.ts\" --fix",
     "prepare": "npm run lint && npm run build && npm test",
     "prebuild": "rimraf lib",
-    "build": "tsc --declaration && tsc tasks/*.ts --noEmit --skipLibCheck",
+    "build": "tsc --declaration && tsc tasks/*.ts --noEmit --skipLibCheck && webpack",
     "postbuild": "ts-node tasks/post-build"
   },
   "repository": {
@@ -42,6 +42,8 @@
   "dependencies": {
     "@calebboyd/semaphore": "^1.3.1",
     "app-builder": "^7.0.4",
+    "@yarnpkg/fslib": "^2.6.0-rc.8",
+    "@yarnpkg/libzip": "^2.2.2",
     "archiver": "^5.3.0",
     "caw": "^2.0.1",
     "chalk": "^2.4.2",
@@ -56,7 +58,8 @@
     "multistream": "^4.1.0",
     "ora": "^3.4.0",
     "resolve-dependencies": "^6.0.8",
-    "rimraf": "^3.0.2"
+    "rimraf": "^3.0.2",
+    "webpack-config-prefabs": "0.0.5"
   },
   "devDependencies": {
     "@types/archiver": "^5.1.1",
@@ -82,6 +85,7 @@
     "tslint": "^6.1.1",
     "tslint-config-prettier": "^1.18.0",
     "tslint-plugin-prettier": "^2.3.0",
-    "typescript": "^4.6.4"
+    "typescript": "^4.6.4",
+    "webpack-cli": "^4.8.0"
   }
 }

src/compiler.ts

@@ -136,7 +136,7 @@ export class NexeCompiler {
   }
 
   @bound
-  addResource(absoluteFileName: string, content?: Buffer | string | File | null) {
+  addResource(absoluteFileName: string, content?: Buffer | string | File) {
     return this.bundle.addResource(absoluteFileName, content)
   }
 

src/fs/SnapshotZipFS.ts

@@ -0,0 +1,390 @@
+import { Libzip } from '@yarnpkg/libzip'
+import {
+  FakeFS,
+  PortablePath,
+  ZipFS,
+  ZipOpenFS,
+  RmdirOptions,
+  OpendirOptions,
+} from '@yarnpkg/fslib'
+import { ZipOpenFSOptions } from '@yarnpkg/fslib/lib/ZipOpenFS'
+import {
+  WriteFileOptions,
+  CreateWriteStreamOptions,
+  BasePortableFakeFS,
+  Dirent,
+  MkdirOptions,
+  Dir,
+} from '@yarnpkg/fslib/lib/FakeFS'
+import { CustomDir } from '@yarnpkg/fslib/lib/algorithms/opendir'
+import { FSPath, ppath, npath, Filename } from '@yarnpkg/fslib/lib/path'
+// @ts-ignore
+import { resolve, toNamespacedPath } from 'path'
+import { WriteStream, constants } from 'fs'
+
+export type SnapshotZipFSOptions = {
+  baseFs: FakeFS<PortablePath>
+  libzip: Libzip | (() => Libzip)
+  zipFs: ZipFS
+}
+
+import { uniqBy } from 'lodash'
+function uniqReaddir(arr: Array<string | Dirent>) {
+  return uniqBy(arr, (s: string | Dirent) => (typeof s === 'string' ? s : s.name))
+}
+
+export class SnapshotZipFS extends BasePortableFakeFS {
+  zipFs: ZipFS
+  baseFs: FakeFS<PortablePath>
+  constructor(opts: SnapshotZipFSOptions) {
+    super()
+    this.zipFs = opts.zipFs
+    this.baseFs = opts.baseFs
+  }
+  private readonly fdMap: Map<number, [ZipFS, number]> = new Map()
+  private nextFd = 3
+
+  async makeCallPromise<T>(
+    p: FSPath<PortablePath>,
+    discard: () => Promise<T>,
+    accept: (zipFS: ZipFS, zipInfo: { subPath: PortablePath }) => Promise<T>,
+    { requireSubpath = true }: { requireSubpath?: boolean } = {}
+  ): Promise<T> {
+    if (typeof p !== 'string') return await discard()
+
+    const normalizedP = this.resolve(p)
+
+    const zipInfo = this.findZip(normalizedP)
+    if (!zipInfo) return await discard()
+
+    if (requireSubpath && zipInfo.subPath === '/') return await discard()
+
+    return await accept(this.zipFs, zipInfo)
+  }
+
+  makeCallSync<T>(
+    p: FSPath<PortablePath>,
+    discard: () => T,
+    accept: (zipFS: ZipFS, zipInfo: { subPath: PortablePath; archivePath: string }) => T,
+    { requireSubpath = true }: { requireSubpath?: boolean } = {}
+  ): T {
+    if (typeof p !== 'string') return discard()
+
+    const normalizedP = this.resolve(p)
+
+    const zipInfo = this.findZip(normalizedP)
+    if (!zipInfo) return discard()
+
+    if (requireSubpath && zipInfo.subPath === '/') return discard()
+
+    return accept(this.zipFs, { archivePath: '', ...zipInfo })
+  }
+
+  async realpathPromise(p: PortablePath) {
+    return await this.makeCallPromise(
+      p,
+      async () => {
+        return await this.baseFs.realpathPromise(p)
+      },
+      async (zipFs, { subPath }) => {
+        return await zipFs.realpathPromise(subPath)
+      }
+    )
+  }
+
+  realpathSync(p: PortablePath) {
+    return this.makeCallSync(
+      p,
+      () => {
+        return this.baseFs.realpathSync(p)
+      },
+      (zipFs, { subPath }) => {
+        return zipFs.realpathSync(subPath)
+      }
+    )
+  }
+
+  findZip(p: PortablePath) {
+    p = this.resolve(p)
+    const pathsToTry = Array.from(
+      new Set([
+        p,
+        resolve('/snapshot', p),
+        ppath.resolve(
+          npath.toPortablePath('/snapshot'),
+          npath.toPortablePath(
+            npath.relative(npath.fromPortablePath(process.cwd()), npath.fromPortablePath(p))
+          )
+        ),
+        ppath.resolve(
+          npath.toPortablePath('/snapshot'),
+          npath.toPortablePath(
+            npath.relative(
+              toNamespacedPath(npath.fromPortablePath(process.cwd())),
+              toNamespacedPath(npath.fromPortablePath(p))
+            )
+          )
+        ),
+      ])
+    )
+    for (const path of pathsToTry) {
+      const portablePath = npath.toPortablePath(path)
+      if (this.zipFs.existsSync(portablePath)) {
+        return {
+          subPath: portablePath,
+        }
+      }
+    }
+  }
+
+  async copyFilePromise(sourceP: PortablePath, destP: PortablePath, flags: number = 0) {
+    const fallback = async (
+      sourceFs: FakeFS<PortablePath>,
+      sourceP: PortablePath,
+      destFs: FakeFS<PortablePath>,
+      destP: PortablePath
+    ) => {
+      if ((flags & constants.COPYFILE_FICLONE_FORCE) !== 0)
+        throw Object.assign(
+          new Error(`EXDEV: cross-device clone not permitted, copyfile '${sourceP}' -> ${destP}'`),
+          { code: `EXDEV` }
+        )
+      if (flags & constants.COPYFILE_EXCL && (await this.existsPromise(sourceP)))
+        throw Object.assign(
+          new Error(`EEXIST: file already exists, copyfile '${sourceP}' -> '${destP}'`),
+          { code: `EEXIST` }
+        )
+
+      let content
+      try {
+        content = await sourceFs.readFilePromise(sourceP)
+      } catch (error) {
+        throw Object.assign(
+          new Error(`EINVAL: invalid argument, copyfile '${sourceP}' -> '${destP}'`),
+          { code: `EINVAL` }
+        )
+      }
+
+      await destFs.writeFilePromise(destP, content)
+    }
+
+    return await this.makeCallPromise(
+      sourceP,
+      async () => {
+        return await this.baseFs.copyFilePromise(sourceP, destP, flags)
+      },
+      async (zipFsS, { subPath: subPathS }) => {
+        return await fallback(zipFsS, subPathS, this.baseFs, destP)
+      }
+    )
+  }
+
+  copyFileSync(sourceP: PortablePath, destP: PortablePath, flags: number = 0) {
+    const fallback = (
+      sourceFs: FakeFS<PortablePath>,
+      sourceP: PortablePath,
+      destFs: FakeFS<PortablePath>,
+      destP: PortablePath
+    ) => {
+      if ((flags & constants.COPYFILE_FICLONE_FORCE) !== 0)
+        throw Object.assign(
+          new Error(`EXDEV: cross-device clone not permitted, copyfile '${sourceP}' -> ${destP}'`),
+          { code: `EXDEV` }
+        )
+      if (flags & constants.COPYFILE_EXCL && this.existsSync(sourceP))
+        throw Object.assign(
+          new Error(`EEXIST: file already exists, copyfile '${sourceP}' -> '${destP}'`),
+          { code: `EEXIST` }
+        )
+
+      let content
+      try {
+        content = sourceFs.readFileSync(sourceP)
+      } catch (error) {
+        throw Object.assign(
+          new Error(`EINVAL: invalid argument, copyfile '${sourceP}' -> '${destP}'`),
+          { code: `EINVAL` }
+        )
+      }
+
+      destFs.writeFileSync(destP, content)
+    }
+
+    return this.makeCallSync(
+      sourceP,
+      () => {
+        return this.baseFs.copyFileSync(sourceP, destP, flags)
+      },
+      (zipFsS, { subPath: subPathS }) => {
+        return fallback(zipFsS, subPathS, this.baseFs, destP)
+      }
+    )
+  }
+  async readdirPromise(p: PortablePath): Promise<Array<Filename>>
+  async readdirPromise(
+    p: PortablePath,
+    opts: { withFileTypes: false } | null
+  ): Promise<Array<Filename>>
+  async readdirPromise(p: PortablePath, opts: { withFileTypes: true }): Promise<Array<Dirent>>
+  async readdirPromise(
+    p: PortablePath,
+    opts: { withFileTypes: boolean }
+  ): Promise<Array<Filename> | Array<Dirent>>
+  async readdirPromise(
+    p: PortablePath,
+    opts?: { withFileTypes?: boolean } | null
+  ): Promise<Array<string | Dirent>> {
+    const fallback = async () => {
+      return await this.baseFs.readdirPromise(p, opts as any)
+    }
+    return await this.makeCallPromise(
+      p,
+      fallback,
+      async (zipFs, { subPath }) => {
+        const fallbackPaths: Array<string | Dirent> = await fallback().catch(() => [])
+        return Promise.resolve(
+          uniqReaddir(
+            (fallbackPaths as any[]).concat(await zipFs.readdirPromise(subPath, opts as any))
+          )
+        )
+      },
+      {
+        requireSubpath: false,
+      }
+    )
+  }
+
+  readdirSync(p: PortablePath): Array<Filename>
+  readdirSync(p: PortablePath, opts: { withFileTypes: false } | null): Array<Filename>
+  readdirSync(p: PortablePath, opts: { withFileTypes: true }): Array<Dirent>
+  readdirSync(p: PortablePath, opts: { withFileTypes: boolean }): Array<Filename> | Array<Dirent>
+  readdirSync(p: PortablePath, opts?: { withFileTypes?: boolean } | null): Array<string | Dirent> {
+    const fallback = () => {
+      return this.baseFs.readdirSync(p, opts as any)
+    }
+    return this.makeCallSync(
+      p,
+      fallback,
+      (zipFs, { subPath }) => {
+        let fallbackPaths: Array<string | Dirent> = []
+        try {
+          fallbackPaths = fallback()
+        } catch (e) {}
+        return (fallbackPaths as any[]).concat(uniqReaddir(zipFs.readdirSync(subPath, opts as any)))
+      },
+      {
+        requireSubpath: false,
+      }
+    )
+  }
+
+  async mkdirPromise(p: PortablePath, opts?: MkdirOptions) {
+    return await this.baseFs.mkdirPromise(p, opts)
+  }
+
+  mkdirSync(p: PortablePath, opts?: MkdirOptions) {
+    return this.baseFs.mkdirSync(p, opts)
+  }
+
+  async rmdirPromise(p: PortablePath, opts?: RmdirOptions) {
+    return await this.baseFs.rmdirPromise(p, opts)
+  }
+
+  rmdirSync(p: PortablePath, opts?: RmdirOptions) {
+    return this.baseFs.rmdirSync(p, opts)
+  }
+
+  async opendirPromise(p: PortablePath, opts?: OpendirOptions) {
+    return Promise.resolve(this.zipFs.opendirSync(p, opts))
+  }
+
+  opendirSync(p: PortablePath, opts?: OpendirOptions) {
+    const zipInfo = this.findZip(p)
+    let zipFsDir: Dir<PortablePath> | null = null
+    if (zipInfo) {
+      zipFsDir = this.zipFs.opendirSync(zipInfo.subPath)
+    }
+    let realFsDir: Dir<PortablePath> | null = null
+    try {
+      realFsDir = this.baseFs.opendirSync(p)
+    } catch (e) {
+      if (!zipFsDir) throw e
+    }
+    const seen = new Set()
+    const nextDirent = () => {
+      const entry = realFsDir?.readSync() || zipFsDir?.readSync()
+      if (entry && !seen.has(entry.name)) {
+        seen.add(entry.name)
+        return entry
+      }
+      return null
+    }
+
+    const onClose = () => {
+      zipFsDir?.closeSync()
+      realFsDir?.closeSync()
+    }
+
+    return new CustomDir(p, nextDirent, { onClose })
+  }
+
+  accessPromise = ZipOpenFS.prototype.accessPromise
+  accessSync = ZipOpenFS.prototype.accessSync
+  appendFilePromise = ZipOpenFS.prototype.appendFilePromise
+  appendFileSync = ZipOpenFS.prototype.appendFileSync
+  chmodPromise = ZipOpenFS.prototype.chmodPromise
+  chmodSync = ZipOpenFS.prototype.chmodSync
+  fchmodPromise = ZipOpenFS.prototype.fchmodPromise
+  fchmodSync = ZipOpenFS.prototype.fchmodSync
+  chownPromise = ZipOpenFS.prototype.chownPromise
+  chownSync = ZipOpenFS.prototype.chownSync
+  fchownPromise = ZipOpenFS.prototype.fchownPromise
+  fchownSync = ZipOpenFS.prototype.fchownSync
+  closePromise = ZipOpenFS.prototype.closePromise
+  closeSync = ZipOpenFS.prototype.closeSync
+  createReadStream = ZipOpenFS.prototype.createReadStream
+  createWriteStream = ZipOpenFS.prototype.createWriteStream
+  existsPromise = ZipOpenFS.prototype.existsPromise
+  existsSync = ZipOpenFS.prototype.existsSync
+  fstatPromise = ZipOpenFS.prototype.fstatPromise
+  fstatSync = ZipOpenFS.prototype.fstatSync
+  getExtractHint = ZipOpenFS.prototype.getExtractHint
+  getRealPath = ZipOpenFS.prototype.getRealPath
+  linkPromise = ZipOpenFS.prototype.linkPromise
+  linkSync = ZipOpenFS.prototype.linkSync
+  lstatPromise = ZipOpenFS.prototype.lstatPromise
+  lstatSync = ZipOpenFS.prototype.lstatSync
+  openPromise = ZipOpenFS.prototype.openPromise
+  openSync = ZipOpenFS.prototype.openSync
+  readFilePromise = ZipOpenFS.prototype.readFilePromise
+  readFileSync = ZipOpenFS.prototype.readFileSync
+  readlinkPromise = ZipOpenFS.prototype.readlinkPromise
+  readlinkSync = ZipOpenFS.prototype.readlinkSync
+  readPromise = ZipOpenFS.prototype.readPromise
+  readSync = ZipOpenFS.prototype.readSync
+  renamePromise = ZipOpenFS.prototype.renamePromise
+  renameSync = ZipOpenFS.prototype.renameSync
+  resolve = ZipOpenFS.prototype.resolve
+  statPromise = ZipOpenFS.prototype.statPromise
+  statSync = ZipOpenFS.prototype.statSync
+  symlinkPromise = ZipOpenFS.prototype.symlinkPromise
+  symlinkSync = ZipOpenFS.prototype.symlinkSync
+  truncatePromise = ZipOpenFS.prototype.truncatePromise
+  truncateSync = ZipOpenFS.prototype.truncateSync
+  ftruncatePromise = ZipOpenFS.prototype.ftruncatePromise
+  ftruncateSync = ZipOpenFS.prototype.ftruncateSync
+  unlinkPromise = ZipOpenFS.prototype.unlinkPromise
+  unlinkSync = ZipOpenFS.prototype.unlinkSync
+  unwatchFile = ZipOpenFS.prototype.unwatchFile
+  utimesPromise = ZipOpenFS.prototype.utimesPromise
+  utimesSync = ZipOpenFS.prototype.utimesSync
+  watch = ZipOpenFS.prototype.watch
+  watchFile = ZipOpenFS.prototype.watchFile
+  writeFilePromise = ZipOpenFS.prototype.writeFilePromise
+  writeFileSync = ZipOpenFS.prototype.writeFileSync
+  writePromise = ZipOpenFS.prototype.writePromise
+  writeSync = ZipOpenFS.prototype.writeSync
+
+  // @ts-ignore
+  remapFd = ZipOpenFS.prototype.remapFd
+}

src/fs/bundle.ts

@@ -28,7 +28,7 @@ export class Bundle {
     return Array.from(this.files)
   }
 
-  public addResource(absoluteFileName: string, content?: File | Buffer | string | null) {
+  public addResource(absoluteFileName: string, content?: File | Buffer | string) {
     const destPath = makeRelativeToZip(this.cwd, absoluteFileName)
     if (!this.files.has(destPath)) {
       if (content == null) {

src/fs/patch.ts

@@ -1,329 +1,76 @@
-import { Stats } from 'fs'
-import { getLatestGitRelease } from '../releases'
+import { getLibzipSync } from '@yarnpkg/libzip'
+import { patchFs, npath, PosixFS, NodeFS, ZipFS } from '@yarnpkg/fslib'
+import { SnapshotZipFS } from './SnapshotZipFS'
+import * as assert from 'assert'
+import * as constants from 'constants'
 
-export interface NexeBinary {
+export interface NexeHeader {
   blobPath: string
-  resources: { [key: string]: number[] }
   layout: {
-    stat: Stats
     resourceStart: number
-    contentSize?: number
-    contentStart?: number
-    resourceSize?: number
+    resourceSize: number
+    contentSize: number
+    contentStart: number
   }
 }
 
 let originalFsMethods: any = null
 let lazyRestoreFs = () => {}
+const patches = (process as any).nexe.patches || {}
+delete (process as any).nexe
 
-// optional Win32 file namespace prefix followed by drive letter and colon
-const windowsFullPathRegex = /^(\\{2}\?\\)?([a-zA-Z]):/
-
-const upcaseDriveLetter = (s: string): string =>
-  s.replace(windowsFullPathRegex, (_match, ns, drive) => `${ns || ''}${drive.toUpperCase()}:`)
-
-function shimFs(binary: NexeBinary, fs: any = require('fs')) {
+function shimFs(binary: NexeHeader, fs: typeof import('fs') = require('fs')) {
   if (originalFsMethods !== null) {
     return
   }
+
   originalFsMethods = Object.assign({}, fs)
-  const { blobPath, resources: manifest } = binary,
-    { resourceStart, stat } = binary.layout,
-    directories: { [key: string]: { [key: string]: boolean } } = {},
-    notAFile = '!@#$%^&*',
-    isWin = process.platform.startsWith('win'),
-    isString = (x: any): x is string => typeof x === 'string' || x instanceof String,
-    noop = () => {},
-    path = require('path'),
-    winPath: (key: string) => string = isWin ? upcaseDriveLetter : (s) => s,
-    baseDir = winPath(path.dirname(process.execPath))
+
+  const realFs: typeof fs = { ...fs }
+  const nodeFs = new NodeFS(realFs)
+
+  const blob = Buffer.allocUnsafe(binary.layout.resourceSize)
+  const blobFd = realFs.openSync(binary.blobPath, 'r')
+  const bytesRead = realFs.readSync(
+    blobFd,
+    blob,
+    0,
+    binary.layout.resourceSize,
+    binary.layout.resourceStart
+  )
+  assert.equal(bytesRead, binary.layout.resourceSize)
+
+  const zipFs = new ZipFS(blob, {
+    libzip: getLibzipSync(),
+    readOnly: true,
+  })
+  const snapshotZipFS = new SnapshotZipFS({
+    libzip: getLibzipSync(),
+    zipFs,
+    baseFs: nodeFs,
+  })
+  const posixSnapshotZipFs = new PosixFS(snapshotZipFS)
+  patchFs(fs, posixSnapshotZipFs)
+  const { readFileSync } = fs
 
   let log = (_: string) => true
   let loggedManifest = false
   if ((process.env.DEBUG || '').toLowerCase().includes('nexe:require')) {
     log = (text: string) => {
-      setupManifest()
       if (!loggedManifest) {
-        process.stderr.write('[nexe] - MANIFEST' + JSON.stringify(manifest, null, 4) + '\n')
-        process.stderr.write('[nexe] - DIRECTORIES' + JSON.stringify(directories, null, 4) + '\n')
+        // TODO anything meaningful to log here?
         loggedManifest = true
       }
       return process.stderr.write('[nexe] - ' + text + '\n')
     }
   }
-
-  const getKey = function getKey(filepath: string | Buffer | null): string {
-    if (Buffer.isBuffer(filepath)) {
-      filepath = filepath.toString()
-    }
-    if (!isString(filepath)) {
-      return notAFile
-    }
-    let key = path.resolve(baseDir, filepath)
-
-    return winPath(key)
-  }
-
-  const statTime = function () {
-    return {
-      atime: new Date(stat.atime),
-      mtime: new Date(stat.mtime),
-      ctime: new Date(stat.ctime),
-      birthtime: new Date(stat.birthtime),
-    }
-  }
-
-  let BigInt: Function
-  try {
-    BigInt = eval('BigInt')
-  } catch (ignored) {}
-
-  const minBlocks = Math.max(Math.ceil(stat.blksize / 512), 1)
-  const createStat = function (extensions: any, options: any) {
-    const stat = Object.assign(new fs.Stats(), binary.layout.stat, statTime(), extensions)
-    if ('size' in extensions) {
-      //Assume non adjustable allocation size for file system
-      stat.blocks = Math.ceil(stat.size / stat.blksize) * minBlocks
-    }
-    if (options && options.bigint && typeof BigInt !== 'undefined') {
-      for (const k in stat) {
-        if (Object.prototype.hasOwnProperty.call(stat, k) && typeof stat[k] === 'number') {
-          stat[k] = BigInt(stat[k])
-        }
-      }
-    }
-    return stat
-  }
-
-  const ownStat = function (filepath: any, options: any) {
-    setupManifest()
-    const key = getKey(filepath)
-    if (directories[key]) {
-      let mode = binary.layout.stat.mode
-      mode |= fs.constants.S_IFDIR
-      mode &= ~fs.constants.S_IFREG
-      return createStat({ mode, size: 0 }, options)
-    }
-    if (manifest[key]) {
-      return createStat({ size: manifest[key][1] }, options)
-    }
-  }
-
-  const getStat = function (fn: string) {
-    return function stat(filepath: string | Buffer, options: any, callback: any) {
-      let stat: any
-      if (typeof options === 'function') {
-        callback = options
-        stat = ownStat(filepath, null)
-      } else {
-        stat = ownStat(filepath, options)
-      }
-      if (stat) {
-        process.nextTick(() => {
-          callback(null, stat)
-        })
-      } else {
-        return originalFsMethods[fn].apply(fs, arguments)
-      }
-    }
-  }
-
-  function makeLong(filepath: string) {
-    return (path as any)._makeLong && (path as any)._makeLong(filepath)
-  }
-
-  function fileOpts(options: any) {
-    return !options ? {} : isString(options) ? { encoding: options } : options
-  }
-
-  let setupManifest = () => {
-    Object.keys(manifest).forEach((filepath) => {
-      const entry = manifest[filepath]
-      const absolutePath = getKey(filepath)
-      const longPath = makeLong(absolutePath)
-      const normalizedPath = winPath(path.normalize(filepath))
-
-      if (!manifest[absolutePath]) {
-        manifest[absolutePath] = entry
-      }
-      if (longPath && !manifest[longPath]) {
-        manifest[longPath] = entry
-      }
-      if (!manifest[normalizedPath]) {
-        manifest[normalizedPath] = manifest[filepath]
-      }
-
-      let currentDir = path.dirname(absolutePath)
-      let prevDir = absolutePath
-
-      while (currentDir !== prevDir) {
-        directories[currentDir] = directories[currentDir] || {}
-        directories[currentDir][path.basename(prevDir)] = true
-        const longDir = makeLong(currentDir)
-        if (longDir && !directories[longDir]) {
-          directories[longDir] = directories[currentDir]
-        }
-        prevDir = currentDir
-        currentDir = path.dirname(currentDir)
-      }
-    })
-    ;(manifest[notAFile] as any) = false
-    ;(directories[notAFile] as any) = false
-    setupManifest = noop
-  }
-
-  //naive patches intended to work for most use cases
-  const nfs: any = {
-    existsSync: function existsSync(filepath: string) {
-      setupManifest()
-      const key = getKey(filepath)
-      if (manifest[key] || directories[key]) {
-        return true
-      }
-      return originalFsMethods.existsSync.apply(fs, arguments)
-    },
-    realpath: function realpath(filepath: any, options: any, cb: any): void {
-      setupManifest()
-      const key = getKey(filepath)
-      if (isString(filepath) && (manifest[filepath] || manifest[key])) {
-        return process.nextTick(() => cb(null, filepath))
-      }
-      return originalFsMethods.realpath.call(fs, filepath, options, cb)
-    },
-    realpathSync: function realpathSync(filepath: any, options: any) {
-      setupManifest()
-      const key = getKey(filepath)
-      if (manifest[key]) {
-        return filepath
-      }
-      return originalFsMethods.realpathSync.call(fs, filepath, options)
-    },
-    readdir: function readdir(filepath: string | Buffer, options: any, callback: any) {
-      setupManifest()
-      const dir = directories[getKey(filepath)]
-      if (dir) {
-        if ('function' === typeof options) {
-          callback = options
-          options = { encoding: 'utf8' }
-        }
-        process.nextTick(() => callback(null, Object.keys(dir)))
-      } else {
-        return originalFsMethods.readdir.apply(fs, arguments)
-      }
-    },
-    readdirSync: function readdirSync(filepath: string | Buffer, options: any) {
-      setupManifest()
-      const dir = directories[getKey(filepath)]
-      if (dir) {
-        return Object.keys(dir)
-      }
-      return originalFsMethods.readdirSync.apply(fs, arguments)
-    },
-
-    readFile: function readFile(filepath: any, options: any, callback: any) {
-      setupManifest()
-      const entry = manifest[getKey(filepath)]
-      if (!entry) {
-        return originalFsMethods.readFile.apply(fs, arguments)
-      }
-      const [offset, length] = entry
-      const resourceOffset = resourceStart + offset
-      const encoding = fileOpts(options).encoding
-      callback = typeof options === 'function' ? options : callback
-
-      originalFsMethods.open(blobPath, 'r', function (err: Error, fd: number) {
-        if (err) return callback(err, null)
-        originalFsMethods.read(
-          fd,
-          Buffer.alloc(length),
-          0,
-          length,
-          resourceOffset,
-          function (error: Error, bytesRead: number, result: Buffer) {
-            if (error) {
-              return originalFsMethods.close(fd, function () {
-                callback(error, null)
-              })
-            }
-            originalFsMethods.close(fd, function (err: Error) {
-              if (err) {
-                return callback(err, result)
-              }
-              callback(err, encoding ? result.toString(encoding) : result)
-            })
-          }
-        )
-      })
-    },
-    createReadStream: function createReadStream(filepath: any, options: any) {
-      setupManifest()
-      const entry = manifest[getKey(filepath)]
-      if (!entry) {
-        return originalFsMethods.createReadStream.apply(fs, arguments)
-      }
-      const [offset, length] = entry
-      const resourceOffset = resourceStart + offset
-      const opts = fileOpts(options)
-
-      return originalFsMethods.createReadStream(
-        blobPath,
-        Object.assign({}, opts, {
-          start: resourceOffset,
-          end: resourceOffset + length - 1,
-        })
-      )
-    },
-    readFileSync: function readFileSync(filepath: any, options: any) {
-      setupManifest()
-      const entry = manifest[getKey(filepath)]
-      if (!entry) {
-        return originalFsMethods.readFileSync.apply(fs, arguments)
-      }
-      const [offset, length] = entry
-      const resourceOffset = resourceStart + offset
-      const encoding = fileOpts(options).encoding
-      const fd = originalFsMethods.openSync(process.execPath, 'r')
-      const result = Buffer.alloc(length)
-      originalFsMethods.readSync(fd, result, 0, length, resourceOffset)
-      originalFsMethods.closeSync(fd)
-      return encoding ? result.toString(encoding) : result
-    },
-    statSync: function statSync(filepath: string | Buffer, options: any) {
-      const stat = ownStat(filepath, options)
-      if (stat) {
-        return stat
-      }
-      return originalFsMethods.statSync.apply(fs, arguments)
-    },
-    stat: getStat('stat'),
-    lstat: getStat('lstat'),
-    lstatSync: function statSync(filepath: string | Buffer, options: any) {
-      const stat = ownStat(filepath, options)
-      if (stat) {
-        return stat
-      }
-      return originalFsMethods.lstatSync.apply(fs, arguments)
-    },
-  }
-  if (typeof fs.exists === 'function') {
-    nfs.exists = function (filepath: string, cb: Function) {
-      cb = cb || noop
-      const exists = nfs.existsSync(filepath)
-      process.nextTick(() => cb(exists))
-    }
-  }
-
-  const patches = (process as any).nexe.patches || {}
-  delete (process as any).nexe
   patches.internalModuleReadFile = function (this: any, original: any, ...args: any[]) {
-    setupManifest()
-    const filepath = getKey(args[0])
-    if (manifest[filepath]) {
-      log('read     (hit)              ' + filepath)
-      return nfs.readFileSync(filepath, 'utf-8')
+    log(`internalModuleReadFile ${args[0]}`)
+    try {
+      return fs.readFileSync(args[0], 'utf-8')
+    } catch (e) {
+      return null
     }
-    log('read          (miss)       ' + filepath)
-    return original.call(this, ...args)
   }
   let returningArray: boolean
   patches.internalModuleReadJSON = function (this: any, original: any, ...args: any[]) {
@@ -334,99 +81,21 @@ function shimFs(binary: NexeBinary, fs: any = require('fs')) {
       : res
   }
   patches.internalModuleStat = function (this: any, original: any, ...args: any[]) {
-    setupManifest()
-    const filepath = getKey(args[0])
-    if (manifest[filepath]) {
-      log('stat     (hit)              ' + filepath + '   ' + 0)
+    log(`internalModuleStat ${args[0]}`)
+    try {
+      const stat = fs.statSync(args[0])
+      if (stat.isDirectory()) return 1
       return 0
-    }
-    if (directories[filepath]) {
-      log('stat dir (hit)              ' + filepath + '   ' + 1)
-      return 1
-    }
-    const res = original.call(this, ...args)
-    if (res === 0) {
-      log('stat          (miss)        ' + filepath + '   ' + res)
-    } else if (res === 1) {
-      log('stat dir      (miss)        ' + filepath + '   ' + res)
-    } else {
-      log('stat                 (fail) ' + filepath + '   ' + res)
-    }
-    return res
-  }
-
-  if (typeof fs.exists === 'function') {
-    nfs.exists = function (filepath: string, cb: Function) {
-      cb = cb || noop
-      const exists = nfs.existsSync(filepath)
-      if (!exists) {
-        return originalFsMethods.exists(filepath, cb)
-      }
-      process.nextTick(() => cb(exists))
+    } catch (e) {
+      return -constants.ENOENT
     }
   }
-
-  if (typeof fs.copyFile === 'function') {
-    nfs.copyFile = function (filepath: string, dest: string, flags: number, callback: Function) {
-      setupManifest()
-      const entry = manifest[getKey(filepath)]
-      if (!entry) {
-        return originalFsMethods.copyFile.apply(fs, arguments)
-      }
-      if (typeof flags === 'function') {
-        callback = flags
-        flags = 0
-      }
-      nfs.readFile(filepath, (err: any, buffer: any) => {
-        if (err) {
-          return callback(err)
-        }
-        originalFsMethods.writeFile(dest, buffer, (err: any) => {
-          if (err) {
-            return callback(err)
-          }
-          callback(null)
-        })
-      })
-    }
-    nfs.copyFileSync = function (filepath: string, dest: string) {
-      setupManifest()
-      const entry = manifest[getKey(filepath)]
-      if (!entry) {
-        return originalFsMethods.copyFileSync.apply(fs, arguments)
-      }
-      return originalFsMethods.writeFileSync(dest, nfs.readFileSync(filepath))
-    }
-  }
-
-  if (typeof fs.realpath.native === 'function') {
-    nfs.realpath.native = function realpathNative(filepath: any, options: any, cb: any): void {
-      setupManifest()
-      const key = getKey(filepath)
-      if (isString(filepath) && (manifest[filepath] || manifest[key])) {
-        return process.nextTick(() => cb(null, filepath))
-      }
-      return originalFsMethods.realpath.native.call(fs, filepath, options, cb)
-    }
-    nfs.realpathSync.native = function realpathSyncNative(filepath: any, options: any) {
-      setupManifest()
-      const key = getKey(filepath)
-      if (manifest[key]) {
-        return filepath
-      }
-      return originalFsMethods.realpathSync.native.call(fs, filepath, options)
-    }
-  }
-
-  Object.assign(fs, nfs)
+  // TODO restore patches in restoreFs
 
   lazyRestoreFs = () => {
-    Object.keys(nfs).forEach((key) => {
-      fs[key] = originalFsMethods[key]
-    })
+    Object.assign(fs, originalFsMethods)
     lazyRestoreFs = () => {}
   }
-  return true
 }
 
 function restoreFs() {

src/steps/shim.ts

@@ -5,10 +5,17 @@ export default async function (compiler: NexeCompiler, next: () => Promise<void>
   await next()
   compiler.shims.push(
     wrap(
-      '' +
-        '{{ file("lib/fs/patch.js") }}' +
-        '\nshimFs(process.__nexe)' +
-        `\n${compiler.options.fs ? '' : 'restoreFs()'}`
+      [
+        'process.__nexe = {};',
+        'const fsPatcher = (function() {',
+        'const module = {exports: {}};',
+        'const exports = module.exports;',
+        '{{file("lib/fs/patch.bundle.js")}}',
+        'return module.exports;',
+        '})()',
+        'fsPatcher.shimFs(process.__nexe);',
+        compiler.options.fs ? '' : 'restoreFs();',
+      ].join('\n')
       //TODO support only restoring specific methods
     )
   )

webpack.config.ts

@@ -0,0 +1,7 @@
+import * as wcp from 'webpack-config-prefabs'
+export = wcp.nodeLibrary(module, {
+  enableTypescript: true,
+  entry: './src/fs/patch.ts',
+  minimize: false,
+  outputFilepath: './lib/fs/patch.bundle.js',
+});