Combine: withLatestFrom, 05

code.swift

func setupAdvPipeline() {
    let searchStream = searchBar.searchTextField.textPublisher
        .prepend(searchBar.text!)
        .eraseToAnyPublisher()

    let sparsedSearchStream = searchStream
        .debounce(for: .seconds(0.3), scheduler: DispatchQueue.main)
        .eraseToAnyPublisher()

    let beginRefreshingStream = refreshControl
        .beginRefreshingPublisher
        .withLatestFrom(searchStream)  // <--
        .map { (_, filter) in filter }
        .delay(for: 0.3, scheduler: DispatchQueue.main) // simulate netw. delay
        .eraseToAnyPublisher()

    beginRefreshingStream
        .sink(
            receiveValue: { filter in
                // Dismiss the refresh control.
                self.refreshControl.endRefreshing()
        })
        .store(in: &cancellables)

    let joinedStream = sparsedSearchStream
        .merge(with: beginRefreshingStream)
        .eraseToAnyPublisher()

    joinedStream
        .sink(
            receiveValue: { searchText in
                self.filter = searchText
        })
        .store(in: &cancellables)
}