Microsoft/TypeScript

tsc looses trailing comments in the produced js files

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#60,811 opened on Dec 18, 2024

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 (1 comment) (1 reaction) (0 assignees)TypeScript (6,726 forks)batch import
Domain: Comment EmitHelp WantedPossible Improvement

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Description

🔎 Search Terms

"missing comments", "missing comments in .js output", "trailing comments"

🕗 Version & Regression Information

Happens in every version available in the playground (3.3.3 to v5.8.0-dev.20241218)

⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.7.2#code/MYGwhgzhAECC0G8CwAoa7oHpPQNYFN8AHAWggHsAnAF3wBNoJqwbUNoBbfagC3LtgAKAJSI27DMHIA7CiHwA6EOQDmggEQUa9dcIDc49AF9DWHAWJkqtBvml1URoA

💻 Code

class A {
    // keep-sorted start
    methodA() {
        console.log("sorted");
    }
    // keep-sorted end
}

🙁 Actual behavior

// keep-sorted end is missing in the .js output.

🙂 Expected behavior

// keep-sorted end is retained in the .js output.

Additional information about the issue

No response

Contributor guide

Research direction
Investigate how the TypeScript emitter handles comments that are siblings of class members, specifically the 'keep sorted' comment block. Trace the comment emission logic for class declarations.
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.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
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
TypeScriptGit
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65