Before You File a Proposal Please Confirm You Have Done The Following...

• I havesearched for related issues and found none that match my proposal.
• I have searched thecurrent rule list and found no rules that match my proposal.
• I haveread the FAQ and my problem is not listed.

My proposal is suitable for this project

• I believe my proposal would be useful to the broader TypeScript community (meaning it is not a niche proposal).

Link to the rule's documentation

https://typescript-eslint.io/rules/await-thenable/,https://typescript-eslint.io/rules/no-floating-promises,https://typescript-eslint.io/rules/no-misused-promises

Description

I would like to find a place to lint for providing a sync disposable to anawait using statement. This relates closely to#8858, so maybe await-thenable is the right place for this check? But it also has concerns very adjacent to no-floating-promises and no-misused-promises, so I'm not sure.

Fail

asyncfunctionunhandledRejection(){await using_={async[Symbol.dispose](){thrownewError('dispose error');}}}

Pass

asyncfunctionproperlyHandledRejection(){await using_={async[Symbol.asyncDispose](){thrownewError('dispose error');}}}

Additional Info

The promise rejection inunhandledRejection cannot be caught, since the[Symbol.dispose]() method is called, butis not awaited, by anawait using statement. Only the[Symbol.asyncDispose]() method is awaited.

There's a lot of subtlety here so I've provided a repo to be able to play with variations on this athttps://github.com/kirkwaiblinger/typescript-eslint-repro-await-using