Before You File a Bug Report Please Confirm You Have Done The Following...

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I havesearched for related issues and found none that matched my issue.
• I haveread the FAQ and my problem is not listed.

Playground Link

https://typescript-eslint.io/play/#ts=5.4.3&fileType=.tsx&code=IYZwngdgxgBAZgV2gFwJYHsICoYFNhQAWAMqhLgBQD6IyATvgLYBcMASvgCbABGANrgDK9JgB4AqmWQAOAIJ06wMAD4AlK1nhoAcVzlFydHVG06ZAOYAaGADd0qTtaSdccMrk7KYAbwBQMGDBUXD5OGAAiVEYABwFGPWRgNEwYdEZUZGQPcN8AX19fXAAPaKNkGFBIWEQUDAgYPnRzUnIQClMmAH5WDmBufiERYEYJKTkFJTVWAAU6NNQQXFE7By8-AKhMWgb3EBgAXhgO4ZhOvAISd3ahxlUYVgBtAF0AbgKAuCMKgHdgDJgKJsINs%2BO5UnAdq07usAjAgSB0AIAHSNcwUUHkVT%2BGD5XJAA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6AQwHd3K78ALRE3YAjJOijdoTSODABfEPKA&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA&tokens=false

Repro Code

// contrived exampleasyncfunction*eachLine(_stream:ReadableStream<Uint8Array>):AsyncGenerator<string,void,undefined>{yield"implementation omitted"}exportasyncfunctionlogLines(stream?:ReadableStream<Uint8Array>):Promise<void>{constlines=stream ?eachLine(stream) :["some","defaults"];forawait(constlineoflines){console.log(line)}}

ESLint Config

module.exports={"rules":{"@typescript-eslint/await-thenable":"warn"}}

tsconfig

{"compilerOptions": {"strictNullChecks":true  }}

Expected Result

If a value isAsyncIterable | Iterable, you need afor await...of loop to iterate over it, so the linter doesn't complain.

Actual Result

await-thenable reports

Unexpected `for await...of` of a value that is not async iterable. 8:3 - 8:34> Convert to an ordinary `for...of` loop.

If you apply the suggestion, which in the example is

for(constlineoflines){

then the linter is satisfied but the code is broken and the compiler knows it:

2488: Type 'AsyncGenerator<string, void, undefined> | never[]' must have a '[Symbol.iterator]()' method that returns an iterator. 8:22 - 8:27

Additional Info

It'sfine to usefor await...of to iterate over a sync iterable. It makes sense not to use this construct if youknow that you have a sync iterable, but if you may have either an async iterable or a sync one, then you need it.