Respect types@ exports condition or typesVersions

[nicolo-ribaudo]

Version: Deno 2.1.7

Deno is resolving the wrong types in @babel/[email protected].

Try with this file:

import * as t from "npm:@babel/[email protected]";

type X = t.Identifier;

Go-to-definition goes to /Users/nic/Library/Caches/deno/npm/registry.npmjs.org/@babel/types/7.26.7/lib/index-legacy.d.ts, but it should go to /Users/nic/Library/Caches/deno/npm/registry.npmjs.org/@babel/types/7.26.7/lib/index.d.ts.

These are the relevant parts of package.json:

{
  "name": "@babel/types",
  "version": "7.26.7",
  "main": "./lib/index.js",
  "types": "./lib/index-legacy.d.ts",
  "typesVersions": {
    ">=4.1": {
      "lib/index-legacy.d.ts": [
        "lib/index.d.ts"
      ]
    }
  }
}

The same behavior happens with @babel/[email protected], which actually includes one more "tool" for Deno to resolve TS types (package.json#exports):

{
  "name": "@babel/types",
  "version": "8.0.0-alpha.15",
  "main": "./lib/index.js",
  "types": "./lib/index-legacy.d.ts",
  "typesVersions": {
    ">=4.1": {
      "lib/index-legacy.d.ts": [
        "lib/index.d.ts"
      ]
    }
  },
  "exports": {
    ".": {
      "types@>=4.1": "./lib/index.d.ts",
      "types": "./lib/index-legacy.d.ts",
      "default": "./lib/index.js"
    },
    "./package.json": "./package.json"
  },
  "type": "module"
}

---

Relevant TS docs:

• https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-9.html#exports-is-prioritized-over-typesversions
• https://www.typescriptlang.org/docs/handbook/declaration-files/publishing.html#version-selection-with-typesversions