swift - 如何覆盖 Observable为了测试？

Question

我们正在使用 Swift 2.x（最新）并希望对我们的代码进行 BDD（单元测试）。顺便说一句，我们也在使用RxSwift。我们的覆盖方法不会在我们的自定义测试存根中被调用。我们的代码：

protocol SomethingDeliverable {
    func fetchSomething(somethingId: String, associatedList: String) -> Observable<String>
}

extension SomethingDeliverable {
    func fetchSomething(somethingId: String, associatedList: String) -> Observable<String> {
        return create { observer in
            return NopDisposable.instance
        }
    }
}

为了测试，我们有这个测试代码：

private class StubSomethingApi: SomethingDeliverable {

    var responseClosure: ((AnyObserver<String>) -> Void)?

    func fetchSomething(somethingId: String, associatedList: String) -> Observable<String> {
        return create { observer in
            if let responseClosure = self.responseClosure {
                responseClosure(observer)
            }
            return NopDisposable.instance
        }
    }
}

我们希望返回 Observable< T > 并让 StubSomethingAPI 成功覆盖它以进行测试，而不是 fetchSomething 返回 Observable< String >。我们怎么能做到这一点？

Answer 1

这是你想要的？

protocol SomethingDeliverable {
    associatedtype Element

    func fetchSomething(somethingId: String, associatedList: String) -> Observable<Element>
}

extension SomethingDeliverable {
    func fetchSomething(somethingId: String, associatedList: String) -> Observable<Element> {
        return create { observer in
            return NopDisposable.instance
        }
    }
}

private class StubSomethingApi<T>: SomethingDeliverable {

    typealias Element = T

    var responseClosure: ((AnyObserver<T>) -> Void)?

    func fetchSomething(somethingId: String, associatedList: String) -> Observable<T> {
        return create { observer in
            if let responseClosure = self.responseClosure {
                responseClosure(observer)
            }
            return NopDisposable.instance
        }
    }
}