Support Type Acquisition From Npx Shebang

Originally filed under https://github.com/microsoft/vscode/issues/87834.

Search Terms

shebang, npx, type acquisition

Suggestion

When authoring JS scripts that are to be invoked using npx, it would be great if the typing information could be inferred from the package that npx will call.

Use Cases

I'm currently building a library, where primary use case is to be consumed as executable scripts, with npx as the shebang command (this allows for global execution without the need for prior installation). And since all of the needed functionality is automatically injected into the global scope there is no need for external references. This is intended for portability and ease of authoring.

When authoring these scripts, the desire is to leverage the typings provided by the library called by npx. The assumption here is that the toolchain would detect the npx invocation in the shebang, and load the appropriate typings (local if library is previously installed, or downloaded if not).

Examples

#!/usr/bin/npx @arcsine/nodesh
stdin
  .sort()
  .unique()
  .stdout

In the sample above, stdin is a global variable that should be picked up via intellisense, and the methods it exposes should be searchable (with the associated docs).

Considerations

Alternatively, one thought was to leverage a triple-slash directive, but that is limited as it cannot:

• point to global node modules (without an absolute path)
• reference ephemeral libraries as loaded by npx

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

この issue にはファイル、テスト、エントリーポイントが記載されていません。まず、TypeScript による JavaScript の shebang と自動型取得の処理を追跡し、次に、要求されている npx パッケージ検索を既存の動作と比較してください。npx で呼び出されたスクリプトが、実行時の動作を変更せずにパッケージの型定義と IntelliSense を受け取れるようになれば完了です。