What to put in package.json types field for typescript based libs

Question

I'm a bit confused as to how best develop multiple typescript modules in parallel with code navigation and still publishing the right way. So what should I really put in package.json "types" field?

According to: Typescriptlang.org/publishing.html

I should put a reference to my generated index.d.ts like so:

{
    "name": "awesome",
    "author": "Vandelay Industries",
    "version": "1.0.0",
    "main": "./lib/main.js",
    "types": "./lib/main.d.ts"
}

If I then develop a module in parallel that depends on this one with npm link, code navigation in for example vscode makes me just jump into this definitions file. Which is not what I want.

I want to go into the source file to be able to edit in the dep in parallel. No tsconfig setting with sourcemaps, inlined or not have helped in this regard. I might be missing something here. The only way I've managed my work flow to work decently is to actually point to the source main.ts file instead:

{
    "name": "awesome",
    "author": "Vandelay Industries",
    "version": "1.0.0",
    "main": "./lib/main.js",
    "types": "./src/main.ts"
}

That however would make thing break when published right ?

At least if I put src under .npmignore. I'm failing to understand the best way to have a nice workflow with multiple typescript modules.

I mean, I wouldn't want to have to mangle package.json as part of release process…?

Answer 1

Here is a lighter weight alternative but it requires using PNPM. In your package02 add this to your package.json:

"type": "module",
"exports": {
    ".": "./src/index.ts"
  },
  "types": "./src/index.ts",
  "publishConfig": {
    "exports": {
      ".": "./lib/index.js"
    },
    "types": "./lib/index.d.ts"
  },

When your package is published, the publishConfig options will override the development references in src. Note, I'm building an ESM package with this solution. Not sure about CJS.