Reject promise in redux-form in fetch catch-block - redux-form

Question

How does one throw a new SumbmissionError in a .catch-block without getting a unhandled rejection?
This throws a Unhandled Rejection (SubmissionError)
import { SubmissionError } from 'redux-form';
const submit = (data) => {
console.log(data);
const config = {
method: 'GET'
};
return fetch('http://www.notAvailable.com/', config)
.then(response => {
console.log(response)
})
.catch(err => {
throw new SubmissionError({_error: 'Error'});
});
}
export default submit;

Answer 1

If you return the promise to the onSubmit config / prop or handleSubmit reduxForm should catch the SubmissionError:
const { createStore, combineReducers } = Redux;
const { Provider } = ReactRedux;
const { reduxForm, SubmissionError, reducer } = ReduxForm;
const submit = () => new Promise((resolve, reject) => {
setTimeout(() => reject('500'), 100);
}).catch(e => {
throw new SubmissionError({ _error: 'service error' })
});
const Form = reduxForm({
form: 'example',
onSubmit: submit
})(props => (
<form onSubmit={props.handleSubmit}>
<pre>{JSON.stringify(props, null, 4)}</pre>
<button type="submit">submit</button>
</form>
));
const store = createStore(combineReducers({ form: reducer }));
ReactDOM.render((
<Provider store={store}>
<Form />
</Provider>
), document.getElementById('root'));
JSFiddle: https://jsfiddle.net/pariesz/6srugtwr/