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Splitting a default tuple type across multiple lines breaks highlighting

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#1,040 0 comments 2 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
55/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Tech stack
typescript
Domain
tooling

Research direction

Start by reproducing the issue with the provided TypeScript declaration snippet and inspect the TypeScript TextMate grammar rules involved in multiline tuple defaults. Done means syntax highlighting remains correct below the split tuple, including the following interface and constructor.

Written by the indexing model from the issue text.

Description

JavaScript and TypeScript Nightly version: 5.6.0-dev.20240819

Splitting a tuple across multiple lines, which is used as the default type for a parameter on a method in an interface or class in a declaration file (.d.ts), breaks syntax highlighting below that line.

Code

// Please include a code snippet that demonstrates the issue
export interface Broken {
    a<A extends [number] = [
        number
    ]>(value: number): boolean;

    b(value: number): string;
}

export interface Other {
    constructor(name: string);
}

Broken:
broken_interface

Working:
working_interface

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

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  4. Open a pull request that references the issue number.

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