Test failing

[igorgcustodio]

Hey, first time opening a discussion here, sorry if it is on the wrong topic.

I am creating a new test on our app and it's throwing me an error when asserting the expressions. But this time, it's not telling me what is different. Have anyone faced it before?

The flow is:

await store.send(.onTask) {
            $0.date = Date(timeIntervalSince1970: TimeInterval(1_747_415_196)).formatted(date: .abbreviated, time: .omitted)
        }

        await store.receive(\.onFetchResponse.success, timeout: 1)
        await store.receive(\.onAddText, timeout: 1) { // failing here
            $0.responseStatus = .streaming
            $0.text = "Hello!"
            $0.htmlText = NSAttributedString("Hello!")
        }
        await store.receive(\.onAddTag, timeout: 1) {
            $0.tags = ["Progress Notes"]
        }
        await store.receive(\.onAddText, timeout: 1) { // failing here
            $0.text = "Hello!This is a message"
            $0.htmlText = NSAttributedString("Hello!This is a message")
        }
        await store.receive(\.onFinishStreaming, timeout: 1) {
            $0.date = Date(
                timeIntervalSince1970: TimeInterval(1_747_415_196)
            ).formatted(
                date: .abbreviated,
                time: .shortened
            )
            $0.responseStatus = .loaded
        }

And the error is:

Issue recorded: A state change does not match expectation: …

      Reducer.State(
        _responseStatus: .streaming,
        _tags: Set([]),
        _date: "16 May 2025",
        _text: "Hello!",
        _htmlText: "Hello!"
      )

(Expected: −, Actual: +)

For now, I set exhaustivity to off to be able to pass this test, but I wouldn't like to set it.

[mbrandonw]

Hi @igorgcustodio, can you please provide more information? Which send/receive is causing the error? Do you have custom Equatable conformances on any of these types? If possible, can you try to reduce this problem to a small snippet of code that we can run ourselves and see the failure?

[igorgcustodio]

Hey!

I don't have any custom Equatable for my models.

Here is the code (with changes to not expose sensitive code):

Test file:

@MainActor
@Suite
struct SummaryTests {
    @Test
    func triggerStreaming() async throws {
        let store = TestStore(
            initialState: MyReducer.State(
                clientId: 1000,
                name: "John"
            ),
            reducer: { MyReducer() }
        ) {
            // GMT: Friday, 16 May 2025 17:06:36
            $0.date.now = Date(timeIntervalSince1970: TimeInterval(1_747_415_196))
            $0.sseClient.fetchDetails = { _ in
                AsyncThrowingStream<Summary, any Error> { continuation in
                    continuation.yield(Summary(type: .message, value: "Hello!"))
                    continuation.yield(Summary(type: .source, value: "Progress Notes"))
                    continuation.yield(Summary(type: .message, value: "This is a message"))
                    continuation.finish()
                }
            }
        }

        await store.send(.onTask) {
            $0.date = Date(timeIntervalSince1970: TimeInterval(1_747_415_196)).formatted(date: .abbreviated, time: .omitted)
        }

        await store.receive(\.onFetchResponse.success, timeout: 1)
        await store.receive(\.onAddText, timeout: 1) { // This one is failing
            $0.responseStatus = .streaming
            $0.text = "Hello!"
            $0.htmlText = NSAttributedString("Hello!")
        }
        await store.receive(\.onAddTag, timeout: 1) {
            $0.tags = ["Progress Notes"]
        }
        await store.receive(\.onAddText, timeout: 1) {  // This one is failing
            $0.text = "Hello!This is a message"
            $0.htmlText = NSAttributedString("Hello!This is a message")
        }
        await store.receive(\.onFinishStreaming, timeout: 1) {
            $0.date = Date(
                timeIntervalSince1970: TimeInterval(1_747_415_196)
            ).formatted(
                date: .abbreviated,
                time: .shortened
            )
            $0.responseStatus = .loaded
        }
    }
}

Here it's my reducer:

@Reducer
public struct Summary: Sendable {
    @ObservableState
    public struct State: Equatable, Sendable {
        enum ResponseStatus {
            case loading
            case streaming
            case loaded
        }

        let clientId: Int
        let name: String

        var responseStatus: ResponseStatus = .loading
        var tags: Set<String> = []
        var date = ""
        var text = ""
        var htmlText: NSAttributedString?
    }

    public enum Action: Sendable {
        case onTask
        case onDisclaimerTapped
        case onFetchResponse(TaskResult<AsyncThrowingStream<Summary, any Error>>)
        case onAddTag(String)
        case onAddText(String)
        case onFinishStreaming
    }

    @Dependency(\.date.now) var now
    @Dependency(\.sseClient) var fetchSummary

    public var body: some ReducerOf<Self> {
        Reduce<State, Action> { state, action in
            switch action {
            case .onTask:
                state.date = now.formatted(date: .abbreviated, time: .omitted)
                let clientId = clientId

                return .run { send in
                    await send(
                        .onFetchResponse(
                            TaskResult { try await fetchSummary(clientId) }
                        )
                    )
                }

            case .onDisclaimerTapped:
                return .none

            case let .onFetchResponse(.success(stream)):
                return .run { send in
                    for try await event in stream {
                        switch event.type {
                        case .message:
                            await send(.onAddText(event.value))
                        case .source:
                            await send(.onAddTag(event.value))
                        case .status:
                            break
                        }
                    }
                    await send(.onFinishStreaming)
                }

            case let .onAddTag(tag):
                state.tags.insert(tag)
                return .none

            case let .onAddText(text):
                state.responseStatus = .streaming
                state.text.append(text)
                state.htmlText = state.text.htmlToAttributedString
                return .none

            case .onFinishStreaming:
                state.date = now.formatted(date: .abbreviated, time: .shortened)
                state.responseStatus = .loaded
                return .none

            case let .onFetchResponse(.failure(error)):
                state.responseStatus = .loaded
                print(error)
                return .none
            }
        }
    }
}

[mbrandonw]

Hi @igorgcustodio, unfortunately you haven't provided enough code for me to actually run it myself, but certainly the thing that stands out the most to me is the NSAttributedString. You have to make sure that absolutely everything matches in the string, including all of its attributes:

@Test func foo() {
  let lhs = NSAttributedString("Hi")
  let rhs = NSAttributedString(string: "Hi", attributes: [.foregroundColor:UIColor.red])
  #expect(lhs == rhs)  // ❌
}

I'm not sure why a better diff message isn't being provided for you. When I run a test like this:

@MainActor
@Test func foo() async {
  let store = TestStore(initialState: Feature.State()) { Feature() }
  await store.send(.tap) {
    $0.text = NSAttributedString("Hi")
  }
}
@Reducer private struct Feature {
  struct State: Equatable {
    var text = NSAttributedString("Hi")
  }
  enum Action {
    case tap
  }
  var body: some ReducerOf<Self> {
    Reduce { state, _ in
      state.text = NSAttributedString(string: "Hi", attributes: [.foregroundColor:UIColor.red])
      return .none
    }
  }
}

…I at least get this error:

❌ Issue recorded: A state change does not match expectation: …

    − Feature.State(text: "Hi")
    + Feature.State(text: "Hi")

(Expected: −, Actual: +)

If you can provide a full example that compiles and produces the problem, we will look into it more.

[igorgcustodio]

Hi again, @mbrandonw! You're completely right! The issue was on the NSAttributedString because we do some extra changes around the formatting on that state.text.htmlToAttributedString that were not reflected in the tests, I applied the same modifier to the test string and it passed.

Thank you for pointing it out. I'll close this topic.