如何用RxTest测试一个可观察到的combineLatest？

import XCTest
import RxSwift
import RxTest

class MyCombineLatestTest: XCTestCase {
    var disposeBag: DisposeBag!
    var scheduler: TestScheduler!
    var observer: TestableObserver<OutputType>!
    
    override func setUp() {
        super.setUp()
        disposeBag = DisposeBag()
        scheduler = TestScheduler(initialClock: 0)
        observer = scheduler.createObserver(OutputType.self)
    }
    
    override func tearDown() {
        disposeBag = nil
        scheduler = nil
        observer = nil
        super.tearDown()
    }
    
    // 定义测试方法
    func testCombineLatest() {
        // 测试代码
    }
}

func testCombineLatest() {
    // 创建可观察序列
    let observable1 = scheduler.createHotObservable([
        .next(100, "A"),
        .next(200, "B"),
        .next(300, "C")
    ])
    
    let observable2 = scheduler.createHotObservable([
        .next(150, 1),
        .next(250, 2),
        .next(350, 3)
    ])
    
    // 合并可观察序列
    Observable.combineLatest(observable1, observable2) { ($0, $1) }
        .subscribe(observer)
        .disposed(by: disposeBag)
    
    // 执行测试
    scheduler.start()
    
    // 断言测试结果
    XCTAssertEqual(observer.events, [
        .next(200, ("B", 1)),
        .next(300, ("C", 1)),
        .next(300, ("C", 2)),
        .next(300, ("C", 3))
    ])
}