title: ngrx/store state not updating in reducer function called
body: <p>I am starting to add ngrx(8.4.0) to an existing Angular(8.2) application but one of my actions (see action below) when triggered does not mutate state. </p>
  
  <p>auth.actions.ts (partial)</p>
  
  <pre class="lang-js prettyprint-override"><code>export const loginSuccess = createAction(
    '[SIGN IN] Login Success',
    props&lt;{ user: any; isNewUser: boolean }&gt;()
  </code></pre>
  
  <p>The <code>loginSuccess</code> action is handled by the reducer function below.</p>
  
  <p>auth.reducer.ts (partial)</p>
  
  <pre class="lang-js prettyprint-override"><code>export interface AuthState {
    user: any;
    isNewUser: boolean;
  }
  
  export const initialState: AuthState = {
    user: null,
    isNewUser: null
  };
  
  const authReducer = createReducer(
    initialState,
    on(loginSuccess, (state, { user, isNewUser }) =&gt; ({
      ...state,
      user: user,
      isNewUser: isNewUser
    }))
  );
  
  export function reducer(state: AuthState | undefined, action: Action) {
    return authReducer(state, action);
  }
  </code></pre>
  
  <p>The <code>loginSuccess</code> action is dispatched from an effect called <code>loginWithPopUp</code>.</p>
  
  <pre class="lang-js prettyprint-override"><code>  loginWithPopUp$ = createEffect(() =&gt;
      this.actions$.pipe(
        ofType(authActions.loginWithPopUp),
        distinctUntilChanged(),
        switchMap(action =&gt;
          from(this.authService.signUpWithPopUp()).pipe(
            map((result: firebase.auth.UserCredential) =&gt;
              authActions.loginSuccess({
                user: result.user,
                isNewUser: result.additionalUserInfo.isNewUser
              })
            ),
            tap(() =&gt; this.router.navigate(['/notes'])),
            catchError(() =&gt; of(authActions.loginFail()))
          )
        )
      )
    );
  </code></pre>
  
  <p>Even though my action is triggered and I see the properties <code>user</code> and <code>isNewUser</code> in my action, state is not updated.</p>
  
  <p><a href="https://i.stack.imgur.com/JFMv0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JFMv0.png" alt="unchanged state"></a></p>
  
  <p><code>user</code> and <code>isNewUser</code> populated in the action.</p>
  
  <p><a href="https://i.stack.imgur.com/1DXfe.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1DXfe.png" alt="action"></a></p>
  
  <p>Error that appears on the console.</p>
  
  <p><a href="https://i.stack.imgur.com/3z5se.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3z5se.png" alt="enter image description here"></a></p>