microsoft / microsoft/TypeScript

When using a string value as export for reference, the .d.ts file created with dot notation instead of computed property which can break

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@rbuckton is already working on this.

Since Feb 10, 2025.

Bug Domain: Declaration Emit
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Description

🔎 Search Terms

references, string exports

🕗 Version & Regression Information
  • This changed between versions 5.6 and 5.7.3
  • This changed in commit or PR _______. It's a feature wasn't implemented fully
  • This is the behavior in every version I tried, and I reviewed the FAQ for entries about: Yes
  • I was unable to test this on prior versions because: It's a new feature that isn't fully implemented (string exports)
⏯ Playground Link

https://www.typescriptlang.org/play/?#code/JYOwLgpgTgZghgYwgAgGIHt3IN4F8BQ+EAHgA7pRg5qbJwDOyARAH4bpPIH4D0PyAC3QB3ZABMsAV2TCowSMnkB+ZCHRhgSZGAFwqAAzaZ9ixnElh0AWgToAtqQA2EMHABGzwdAi9+wgZoCpnSO9FhqVLZQUBAIVADmwABuECCKYADkjBHI8eggIHDIbihJcI7AYnQwkFDItg7OGvn4YACepCgAKhD0VAC8ig4UYAAUGQB0PKCkFhkAlBNG6EA

💻 Code

A demo repo

// In a project with references that I forced to export a "private export". I export it as a string value which breaks .d.ts creation
interface ReferenceTo<T extends string> {
  (value: T): T;
  value: T;
}


// The `as "…"` part
export { ReferenceTo as "~ ReferenceTo" };
🙁 Actual behavior

I get the error

a/out/lib/y.d.ts:1:39 - error TS1110: Type expected.

1 export declare const x: import("./x").~ ReferenceTo<"x">;
~

a/out/lib/y.d.ts:1:39 - error TS1110: Type expected.

1 export declare const x: import("./x").~ ReferenceTo<"x">;
~

Found 2 errors.

According to @Andarist it somes to the issue as described in the playground

More in the Bluesky thread: https://bsky.app/profile/andarist.bsky.social/post/3lhrod2ysps2k

🙂 Expected behavior

It will export it as a computed value so it work

export declare const x: import("./x")["~ ReferenceTo"]<"x">;
Additional information about the issue

More in the Bluesky thread: https://bsky.app/profile/andarist.bsky.social/post/3lhrod2ysps2k

It seems it happens with Autocomplete as well.

A demo repo

Contributor guide

Open the contributing guide

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Assessment

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