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JSDoc with @extends, type parameter and member expression gives wrong dts output
🔎 Search Terms
jsdoc type parameter generics extends superclass template
🕗 Version & Regression Information
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about JSDoc type parameters with
@extends
I tried with TypeScript 5.0.0, 5.6.2, and 5.7.0-dev.20241001.
⏯ Minimal repro link
I needed more than one file to reproduce, which I can't do on the playground. Here's a simple reproducer:
https://github.com/blutorange/issue-repro/tree/issue-typescript-missing-type-param
git clone https://github.com/blutorange/issue-repro
cd issue-repro
git checkout issue-typescript-missing-type-param
npm install
npm run build
Then open dist/index.d.ts.
💻 Code
/**
* @template {0|1|2} T
* @extends {Scope.sub.Box<T>}
*/
export class MyComponent extends Scope.sub.Box {
more() {
return "foo";
}
}
🙁 Actual behavior
The class in the extends clause is missing the type parameter. This is a compile error when you validate the .d.ts file.
declare const MyComponent_base: typeof import("./header.js").Box;
/**
* @template {0|1|2} T
* @extends {Scope.sub.Box<T>}
*/
export class MyComponent<T extends 0 | 1 | 2> extends MyComponent_base {
constructor();
more(): string;
}
export {};
🙂 Expected behavior
TypeScript should include the type parameter in the extends clause.
declare const MyComponent_base: typeof import("./header.js").Box;
/**
* @template {0|1|2} T
* @extends {Scope.sub.Box<T>}
*/
export class MyComponent<T extends 0 | 1 | 2> extends MyComponent_base<T> {
constructor();
more(): string;
}
export {};
Additional information about the issue
Only seems to happen when the extends clause is a member expression where TS generate an intermediate declare const ....
Fyi, I came across this issue while investigating how to setup a project for generating type declarations from js files for primefaces/primefaces#12500
