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Lambda function with line break before parentheses produces wrong syntax highlight on the parameters

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#1,053 0 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
typescript, vscode
Domain
tooling

Research direction

Reproduce the highlighting with the TypeScript Nightly extension using the multiline arrow-function example, then compare it with the version without the line break. Trace the TypeScript TextMate grammar rules responsible for arrow-function parameters. Done means the parameter type and delimiters receive the same syntax highlighting in both forms.

Written by the indexing model from the issue text.

Description

JavaScript and TypeScript Nightly version: 5.9.20250330

Code

const clearSet =
(
  set: Set<string>
) => {}

Result

Image

It is normal without the line break.

Image

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

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