"basic"/"relative" moduleResolution

🔍 Search Terms

module resolution, relative paths

✅ Viability Checklist

• 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, new syntax sugar for JS, etc.)
• This isn't a request to add a new utility type: https://github.com/microsoft/TypeScript/wiki/No-New-Utility-Types
• This feature would agree with the rest of our Design Goals: https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals

⭐ Suggestion

Hi all, I am writing a custom JavaScript runtime that only supports module imports using relative paths with file extensions present.

This is akin to browser-based module resolution (minus import maps).

At present, the compilerOptions.moduleResolution settings are:

• classic (deprecated)
• node/node10
• node16
• nodenext
• bundler

I think classic might work but am hesitant to use a deprecated feature.

Could we include a

{
  "compilerOptions": {
    "moduleResolution": "relative"
  }
}

That only permits resolving module import paths that are relative to the current file and requires that import paths include file extensions?

import * as foo from "./foo.js" // 👍 
import * as foo from "./foo.ts" // 👍 

import * as foo from "./foo" // 👎 
import * as foo from "foo" // 👎 

📃 Motivating Example

• Browsers using JavaScript modules without a bundler
• Custom JavaScript resolution algorithms
  • (shameless plug) https://github.com/alshdavid/ion

💻 Use Cases

1. Accurate import semantics for consumers not using Node.js or contexts compatible with Node.js import resolution semantics

首先阅读编译器如何处理现有的模块解析选项 classic、node10、node16、nodenext 和 bundler。跟踪 compilerOptions.moduleResolution 入口点，并比较当前针对相对导入和包导入的测试。完成的标准是：新的相对模式接受带扩展名的相对导入，同时拒绝不带扩展名的导入和非相对导入，并覆盖所请求的示例。