error[E0277]: the trait bound `std::result::Result<(), ()>: wasm_bindgen::__rt::IntoJsResult` is not satisfied
  --> $DIR/async-errors.rs:30:1
   |
30 | #[wasm_bindgen]
   | ^^^^^^^^^^^^^^^ the trait `wasm_bindgen::__rt::IntoJsResult` is not implemented for `std::result::Result<(), ()>`
   |
   = help: the following implementations were found:
             <std::result::Result<(), E> as wasm_bindgen::__rt::IntoJsResult>
             <std::result::Result<T, E> as wasm_bindgen::__rt::IntoJsResult>
   = note: required by `wasm_bindgen::__rt::IntoJsResult::into_js_result`

error[E0277]: the trait bound `std::result::Result<(), BadType>: wasm_bindgen::__rt::IntoJsResult` is not satisfied
  --> $DIR/async-errors.rs:32:1
   |
32 | #[wasm_bindgen]
   | ^^^^^^^^^^^^^^^ the trait `wasm_bindgen::__rt::IntoJsResult` is not implemented for `std::result::Result<(), BadType>`
   |
   = help: the following implementations were found:
             <std::result::Result<(), E> as wasm_bindgen::__rt::IntoJsResult>
             <std::result::Result<T, E> as wasm_bindgen::__rt::IntoJsResult>
   = note: required by `wasm_bindgen::__rt::IntoJsResult::into_js_result`

error[E0277]: the trait bound `wasm_bindgen::JsValue: std::convert::From<BadType>` is not satisfied
  --> $DIR/async-errors.rs:34:1
   |
34 | #[wasm_bindgen]
   | ^^^^^^^^^^^^^^^ the trait `std::convert::From<BadType>` is not implemented for `wasm_bindgen::JsValue`
   |
   = help: the following implementations were found:
             <wasm_bindgen::JsValue as std::convert::From<&'a T>>
             <wasm_bindgen::JsValue as std::convert::From<&'a std::string::String>>
             <wasm_bindgen::JsValue as std::convert::From<&'a str>>
             <wasm_bindgen::JsValue as std::convert::From<MyType>>
           and 62 others
   = note: required because of the requirements on the impl of `std::convert::Into<wasm_bindgen::JsValue>` for `BadType`
   = note: required because of the requirements on the impl of `wasm_bindgen::__rt::IntoJsResult` for `BadType`
   = note: required by `wasm_bindgen::__rt::IntoJsResult::into_js_result`

error[E0277]: the trait bound `std::result::Result<BadType, wasm_bindgen::JsValue>: wasm_bindgen::__rt::IntoJsResult` is not satisfied
  --> $DIR/async-errors.rs:36:1
   |
36 | #[wasm_bindgen]
   | ^^^^^^^^^^^^^^^ the trait `wasm_bindgen::__rt::IntoJsResult` is not implemented for `std::result::Result<BadType, wasm_bindgen::JsValue>`
   |
   = help: the following implementations were found:
             <std::result::Result<(), E> as wasm_bindgen::__rt::IntoJsResult>
             <std::result::Result<T, E> as wasm_bindgen::__rt::IntoJsResult>
   = note: required by `wasm_bindgen::__rt::IntoJsResult::into_js_result`