Add clarifying comments for dual rejection mechanism in body-parser

[VikramAditya33]

The body-parser uses two rejection callbacks (abortCallback and pendingReject) that serve distinct purposes, but the logic requires careful reading to understand. While the implementation is correct, adding brief inline comments would help future maintainers.

[Techvian]

I'd like to work on this issue.

[VikramAditya33]

@Techvian Do you understand the distinction properly? If yes then proceed with an explanation before we make any changes because, clearly I haven't mentioned the distinction between these or anything in the issue description so, I'd love to know how you understand this

[Techvian]

@VikramAditya33 yeah so from what I can tell —

abortCallback fires when the request itself gets aborted (like the client drops mid-stream), while pendingReject is there to reject the promise if something goes wrong during parsing before it resolves — stream error, size limit, etc.

so basically one is handling an external abort, the other is a safety net for internal failures while still waiting.

the logic works fine, just thought a quick comment on each would save the next person from having to trace through the whole thing to understand why both exist.

lmk if I'm off on something!

[VikramAditya33]

Sounds alright to me. Proceed with a PR

[Techvian]

Hi @VikramAditya33, question — for the body-parser.ts file, should I replace the existing comments or add new clarifying ones alongside them?

[VikramAditya33]

totally upto you it should just clarify the things and not overwrite any comment of any different behaviour