setState has wrong type

We have interface:

interface State {
  condition: boolean;
  left: number;
  right: number;
}

and defined state:

  public state: State = {
    condition: true,
    left: 0,
    right: 0,
  };

Consider method:

  public change= (value: number) => {
    this.setState((state) => {
      if(state.condition) {
        return {
          left: value,
        }
      } else {
        return {
          right: value,
        }
      }
    });
  };

This cause an error during compilation.

TS:

...
        Type '{ left: number; right?: undefined; }' is not assignable to type 'Pick<State, "left" | "right">'.
          Types of property 'right' are incompatible.
            Type 'undefined' is not assignable to type 'number'.

Posible Solution:

       setState<K extends keyof S>(
            state: ((prevState: Readonly<S>, props: Readonly<P>) => (Partial<Pick<S, K>> | S | null)) | (Pick<S, K> | S | null),
            callback?: () => void
        ): void;

[laxip]

Im not sure, maybe I should add this issue to DefinitelyTyped/DefinitelyTyped/tree/master/types/react

[aweary]

The React team doesn’t maintain these TypeScript definitions. Please file this issue in the DefinitelyTyped repo. Thanks!