Support @extends block tag.

[fiddleplum]

Search Terms

extends, javascript, jsdoc, generics

Problem

In my JavaScript code I have this:

/**
 * A viewport is where a scene will be rendered through a camera.
 * @extends {CollectionItem<Engine>}
 */
export class Viewport extends CollectionItem {
  ...
}

I am using JavaScript so I can't put the <Engine> tag directly after the extends CollectionItem, but I am using TypeScript 5.5.4 for validating my JavaScript code, enforcing typing through JSDoc tags everywhere.

When I run my code through TypeDoc 0.26.0, I get the warning:

[warning] Encountered an unknown block tag @extends

However, if I remove it, I get the TypeScript error:

Expected CollectionItem<CollectionParentType> type arguments; provide these with an '@extends' tag.

TypeScript knows I'm running JavaScript with JSDoc and supports it with the --checkJs flag, and I believe you guys support JavaScript with JSDoc as well. I understand that TypeScript itself is your primary target.

TypeScript supports the @extends block tag for its inferring of types, and TypeDoc does not.

Suggested Solution

It would be nice if TypeDoc also supported the @extends tag. It isn't normally needed, except when extending from generic classes where you need to specify the generic parameter.

This came up when I upgraded to 0.56.0, and the extra warnings came up (which fixed some other things for me, thank you!). I searched for an existing issue but did not find one.

[fiddleplum]

That was amazingly fast, thanks @Gerrit0!