add --outSuffix compiler option #32373

Search Terms

out, suffix

Suggestion

add --outSuffix compiler option

Use Cases

tsc --module es6 --outSuffix mjs

Examples

Imagine I have a package with file tree:
my_package/
├── a.ts
├── b.ts
├── index.ts
├── package.json
└── tsconfig.json

then I run:
> tsc --module es6 --outSuffix mjs
> tsc --module commonjs --outSuffix js

then the file tree will be:
my_package/
├── a.d.ts
├── a.js
├── a.mjs
├── a.ts
├── b.d.ts
├── b.js
├── b.mjs
├── b.ts
├── index.d.ts
├── index.js
├── index.mjs
├── index.ts
├── package.json
└── tsconfig.json

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.