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String Literal Param in Default Type Definition in Interface Function Causes Breakage

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#1,035 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
typescript
Domain
tooling

Research direction

Reproduce the interface snippet in VS Code with the TypeScript Nightly extension, then inspect the TypeScript TextMate grammar files in this repository. Check how the default type definition and nested string literal affect block-level keyword scopes. Done means the snippet and the listed keywords no longer cause syntax highlighting to break.

Written by the indexing model from the issue text.

Description

Code

let var1;

interface MyInterface {
  func<T = Lowercase<'StringLiteral'>>(): T;
}

let var2;

JavaScript and TypeScript Nightly version: 5.6.0-dev.20240623

Screenshot 2024-06-24 at 12 33 28 PM

Breakage continues for many other keywords at the same block level such as: let, const, export, for, while, interface etc. class itself seems to overcome the breakage.

Dominant language
TypeScript
Stars
471
Forks
149
PR merge metrics
No merged PRs in 30d

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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.

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