[meta] Use the vscode filesystem API for *all* filesystem operations. #8533

With version , VS Code added a new filesystem API, to provide a consistent and reliable experience on different platforms and execution environments (including remote). The extension should use it as much as possible.

The API

vscode.workspace.fs.*
  copy(source: Uri, target: Uri, options?: {overwrite: boolean}): Thenable<void>
  createDirectory(uri: Uri): Thenable<void>
  delete(uri: Uri, options?: {recursive: boolean, useTrash: boolean}): Thenable<void>
  readDirectory(uri: Uri): Thenable<[string, FileType][]>
  readFile(uri: Uri): Thenable<Uint8Array>
  rename(source: Uri, target: Uri, options?: {overwrite: boolean}): Thenable<void>
  stat(uri: Uri): Thenable<FileStat>
  writeFile(uri: Uri, content: Uint8Array): Thenable<void>

vscode.FileStat
vscode.FileType

For reference:

• https://nodejs.org/api/fs.html
• https://github.com/jprichardson/node-fs-extra#methods

How to Switch?

PRs:

• Update the code base to use IFileSystem instead of fs and fs-extra. #7915 (for Use VS Code FS API #6911)
• Use new VS Code filesystem API. #8307 (for Use VS Code FS API #6911)

Tasks:

• identify all current filesystem usage (see [meta] Code health for filesystem interaction. #8801)
• consolidate all filesystem usage into IFileSystem (see [meta] Code health for filesystem interaction. #8801)
• ensure we keep using only our wrapper in the future (see [meta] Code health for filesystem interaction. #8801)
• improve testability (see [meta] Code health for filesystem interaction. #8801)
• use the vscode.workspace.fs API as a replacement:
  • node's "fs" module is completely subsumed by "fs-extra"
  • "fs-extra" module
    • (missing) chmod() -> ???
      • covered by Enable FileSystemProvider to stat a file as readonly vscode#73122 and FileSystemProvider: no way of handling permissions issues vscode#48659
    • (Use VS Code FS API #6911) readFile() -> readFile()
    • (Use VS Code FS API #6911) writeFile() -> writeFile()
    • (Use VS Code FS API #6911) unlink() -> delete()
    • (Use VS Code FS API #6911) stat() -> stat()
    • (missing) lstat() -> ???
      • covered by File Provider: support symbolic link operations vscode#71204
      • maybe use stat() instead?
    • (Use VS Code FS API #6911) mkdirp() -> createDirectory()
    • (Use VS Code FS API #6911) rmdir() -> delete()
    • (Use VS Code FS API #6911) readdir() -> `readDirectory()
    • (Use VS Code FS API #6911) remove() -> delete()
      • this is a recursive delete (i.e. rmtree())
    • (TODO) statSync() -> ???
      • per Support for sync functions in the vscode.workspace.fs API. vscode#84518, not going to happen
      • switch from sync to async?
    • (TODO) readFileSync() -> ???
      • per Support for sync functions in the vscode.workspace.fs API. vscode#84518, not going to happen
      • switch from sync to async?
    • (Use VS Code FS API #6911) createReadStream() - goes away once we use copy()
    • (Use VS Code FS API #6911) stop using createWriteStream() for copy()
    • (missing) createWriteStream() -> ???
      • requested: Add vscode.workspace.fs.createWriteStream(). vscode#84515
  • "tmp" module
    • (missing) file() -> ???
      • requested Add vscode.workspace.fs.mkdtemp(). vscode#84517
  • "glob" module
    • (TODO) glob() -> vscode.workspace.findFiles()
      • see Add more functionality to the "vscode.workspace.fs" API. vscode#84175
  • ...
• drop workarounds
  • (TODO) drop tree traversal code (per Add vscode.workspace.fs.mkdirp(). vscode#84516)
  • (blocked) FileStat.ctime == 0
    • reported: vscode.workspace.fs.stat(): wrong creation time. vscode#84525
    • drop: ...
  • (blocked) unexpected successes
    • reported: vscode.workspace.fs.remove() (and copy()) succeed unexpectedly. vscode#84177
    • drop: ...
  • (blocked) sockets as FileType.File
    • reported: vscode.workspace.fs.stat(): sockets identified as "regular" files. vscode#84524
    • drop: ...