v4.5 regression: The inferred type of '…' cannot be named without a reference to '…'

[OliverJAsh]

Bug Report

🔎 Search Terms

• rxjs
• re-export
• declaration
• composite
• project references

🕗 Version & Regression Information

• This changed between versions 4.4.4 and 4.5.1-rc

⏯ Playground Link

N/A

💻 Code

package.json:

{
  "dependencies": {
    "rxjs": "^7.4.0",
    "typescript": "^4.5.1-rc"
  }
}

tsconfig.json:

{
    "compilerOptions": {
        "target": "ESNext",
        "module": "CommonJS",
        "declaration": true,
        "outDir": "./target/"
    },
    "files": ["./src/main.ts"],
}

src/facade.ts:

export { connectable, EMPTY } from 'rxjs';

src/main.ts:

import * as Rx from './facade';

export const myConnectable = Rx.connectable(Rx.EMPTY);

Steps to reproduce:

• Run yarn
• Run tsc

🙁 Actual behavior

No error, as it behaved in 4.4.4.

🙂 Expected behavior

Error:

$ tsc
src/main.ts:3:14 - error TS2742: The inferred type of 'myConnectable' cannot be named without a reference to '../node_modules/rxjs/dist/types'. This is likely not portable. A type annotation is necessary.

3 export const myConnectable = Rx.connectable(Rx.EMPTY);
               ~~~~~~~~~~~~~


Found 1 error.

---

I am able to workaround this by modifying src/facade.ts like so:

 export { connectable, EMPTY } from 'rxjs';
+export * from 'rxjs/internal/types'

Note also that the error doesn't reproduce if we import directly from rxjs:

src/main.ts:

import { EMPTY, connectable } from 'rxjs';

export const myConnectable = connectable(EMPTY);

[andrewbranch]

Sounds like #46452 (comment) which would be expected for RxJS in node12/nodenext resolution mode, but you’re not in that mode 🤔

[andrewbranch]

It looks like module resolution ignores export maps in --moduleResolution node (expected at least for back compat—we would really break the world if we changed this), but module specifier resolution always looks at export maps.