The await_only_futures lint should not generate a lint if the type of the expression is an extension type. It is a compile-time error to await an expression whose type is an extension type that doesn't implement Future, so the reporting in that case is duplicated.
The
await_only_futureslint should not generate a lint if the type of the expression is an extension type. It is a compile-time error toawaitan expression whose type is an extension type that doesn't implementFuture, so the reporting in that case is duplicated.