react-redux: conditional type inference from alias fails after re-alias support in #42284 #42421
Description
Bug Report
On DT, react-redux/react-redux-tests.tsx:1433:
interface OwnProps { own: string; } const Component: React.FC<OwnProps & ReduxProps> = ({ own, dispatch }) => null; // ~~~~~~~~ 'dispatch' does not exist on PropsWithChildren<OwnProps> const connector = connect(); type ReduxProps = ConnectedProps<typeof connector>;🙂 Expected behavior
The object type that's the first parameter to the arrow function should have two properties own (from OwnProps) and dispatch (from ConnectedProps<typeof connector>.
ConnectedProps is a conditional type with a false branch never, and it looks like the false branch is incorrectly selected:
export type ConnectedProps<TConnector> = TConnector extends InferableComponentEnhancerWithProps<infer TInjectedProps, any> ? TInjectedProps : never;That must be because inference to InferableComponentEnhancerWithProps<infer TInjectedProps, any> fails.
🙁 Actual behavior
Component: React.FC<OwnProps> not : React.FC<OwnProps & DispatchProp>
Workaround
I observed that connect: Connect and also that
interface Connect { (): InferableComponentEnhancer<DispatchProp>; // ... many other properties ... } export type InferableComponentEnhancer<TInjectedProps> = InferableComponentEnhancerWithProps<TInjectedProps, {}>;Manually de-aliasing InferableComponentEnhancer fixes the error:
interface Connect { (): InferableComponentEnhancerWithProps<DispatchProp, {}>; // ... many other properties ... }