Microsoft/TypeScript

Valid JS code reported by TS as illegal code: Keywords cannot contain escape characters

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#54,196 opened on May 9, 2023

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 (10 comments) (0 reactions) (0 assignees)TypeScript (6,726 forks)batch import
BugDomain: ParserHelp Wanted

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Description

Bug Report

🔎 Search Terms

\u{63}onstructor() valid javascript code returns error Keywords cannot contain escape characters escape characters

🕗 Version & Regression Information

  • This is the behavior in every version I tried.

⏯ Playground Link

Playground link with relevant code

💻 Code

class C {
  \u{63}onstructor() {}  // equivalent to: constructor() {}
}

🙁 Actual behavior

Errors in code Keywords cannot contain escape characters.

🙂 Expected behavior

No errors as it is valid javascript code.

Contributor guide

Research direction
Locate the scanner or parser logic that rejects escape sequences in keywords and update it to allow valid Unicode escapes (e.g., \u{63}onstructor) that are legal in JavaScript.
Tech stack
typescript
Domain
compilers
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaScriptTypeScript
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65