microsoft / microsoft/TypeScript

.d.ts emitted from derived classes in JS doesn't include identical override properties

Open
#54,061 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Bug Domain: Declaration Emit
Dominant language
Go
Stars
111k
Forks
14.3k
Avg merge
1d 19h
Merged PRs (30d)
117

Description

export class C {
    updateDisplay() {
    }
}

export class D extends C {
    updateDisplay() {
    }
}

The generated d.ts for JS has export class D extends C {} whereas TS has export declare class D extends C { updateDisplay(): void }

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the provided JavaScript inheritance example and compare its emitted .d.ts with the TypeScript equivalent. Trace declaration emission for the derived override; done when the JavaScript output includes D.updateDisplay(): void as the TypeScript output does.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, typescript
Domain
compilers, devtools
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.