Fosmvvm UI Tests Generator

┌─────────────────────────────────────────────────────────────┐
│                    UI Test Architecture                      │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  Test File (XCTest)                 App Under Test          │
│  ┌──────────────────┐              ┌──────────────────┐     │
│  │ MyViewUITests    │              │ MyView           │     │
│  │                  │              │                  │     │
│  │ presentView() ───┼─────────────►│ Show view with   │     │
│  │   with stub VM   │              │   stubbed data   │     │
│  │                  │              │                  │     │
│  │ Interact via ────┼─────────────►│ UI elements with │     │
│  │   identifiers    │              │   .uiTestingId   │     │
│  │                  │              │                  │     │
│  │ Assert on UI     │              │ .testData────────┼──┐  │
│  │   state          │              │   Transporter    │  │  │
│  │                  │              └──────────────────┘  │  │
│  │ viewModelOps() ◄─┼─────────────────────────────────────┘  │
│  │   verify calls   │              Stub Operations          │
│  └──────────────────┘                                        │
│                                                              │
└─────────────────────────────────────────────────────────────┘

class MyAppViewModelViewTestCase<VM: ViewModel, VMO: ViewModelOperations>:
    ViewModelViewTestCase<VM, VMO>, @unchecked Sendable {

    @MainActor func presentView(
        configuration: TestConfiguration,
        viewModel: VM = .stub(),
        timeout: TimeInterval = 3
    ) throws -> XCUIApplication {
        try presentView(
            testConfiguration: configuration.toJSON(),
            viewModel: viewModel,
            timeout: timeout
        )
    }

    override func setUp() async throws {
        try await super.setUp(
            bundle: Bundle.main,
            resourceDirectoryName: "",
            appBundleIdentifier: "com.example.MyApp"
        )

        continueAfterFailure = false
    }
}

final class MyViewUITests: MyAppViewModelViewTestCase<MyViewModel, MyViewOps> {
    // UI Tests - verify UI state
    func testButtonEnabled() async throws {
        let app = try presentView(viewModel: .stub(enabled: true))
        XCTAssertTrue(app.myButton.isEnabled)
    }

    // Operation Tests - verify operations were called
    func testButtonTap() async throws {
        let app = try presentView(configuration: .requireSomeState())
        app.myButton.tap()

        let stubOps = try viewModelOperations()
        XCTAssertTrue(stubOps.myOperationCalled)
    }
}

private extension XCUIApplication {
    var myButton: XCUIElement {
        buttons.element(matching: .button, identifier: "myButtonIdentifier")
    }
}

// In your test file
protocol MyViewStubOps: ViewModelOperations {}
struct MyViewStubOpsImpl: MyViewStubOps {}

final class MyViewUITests: MyAppViewModelViewTestCase<MyViewModel, MyViewStubOpsImpl> {
    // UI Tests only - no operation verification
    func testDisplaysCorrectly() async throws {
        let app = try presentView(viewModel: .stub(title: "Test"))
        XCTAssertTrue(app.titleLabel.exists)
    }
}

extension XCUIElement {
    var text: String? {
        value as? String
    }

    func typeTextAndWait(_ string: String, timeout: TimeInterval = 2) {
        typeText(string)
        _ = wait(for: \.text, toEqual: string, timeout: timeout)
    }

    func tapMenu() {
        if isHittable {
            tap()
        } else {
            coordinate(withNormalizedOffset: CGVector(dx: 0.5, dy: 0.5)).tap()
        }
    }
}

public struct MyView: ViewModelView {
    #if DEBUG
    @State private var repaintToggle = false
    #endif

    private let viewModel: MyViewModel
    private let operations: MyViewModelOperations

    public var body: some View {
        Button(action: doSomething) {
            Text(viewModel.buttonLabel)
        }
        .uiTestingIdentifier("myButtonIdentifier")
        #if DEBUG
        .testDataTransporter(viewModelOps: operations, repaintToggle: $repaintToggle)
        #endif
    }

    public init(viewModel: MyViewModel) {
        self.viewModel = viewModel
        self.operations = viewModel.operations
    }

    private func doSomething() {
        operations.doSomething()
        toggleRepaint()
    }

    private func toggleRepaint() {
        #if DEBUG
        repaintToggle.toggle()
        #endif
    }
}

public struct MyView: ViewModelView {
    private let viewModel: MyViewModel

    public var body: some View {
        VStack {
            Text(viewModel.title)
            Text(viewModel.description)
        }
        .uiTestingIdentifier("mainContent")
    }

    public init(viewModel: MyViewModel) {
        self.viewModel = viewModel
    }
}

// MyDisplayViewModelOperations.swift
import FOSMVVM
import Foundation

public protocol MyDisplayViewModelOperations: ViewModelOperations {}

#if canImport(SwiftUI)
public final class MyDisplayViewStubOps: MyDisplayViewModelOperations, @unchecked Sendable {
    public init() {}
}
#endif

final class MyDisplayViewUITests: MyAppViewModelViewTestCase<
    MyDisplayViewModel,
    MyDisplayViewStubOps
> {
    // Only test UI state, no operation verification
}

func testButtonDisabledWhenNotReady() async throws {
    let app = try presentView(viewModel: .stub(ready: false))
    XCTAssertFalse(app.submitButton.isEnabled)
}

func testButtonEnabledWhenReady() async throws {
    let app = try presentView(viewModel: .stub(ready: true))
    XCTAssertTrue(app.submitButton.isEnabled)
}

func testSubmitButtonInvokesOperation() async throws {
    let app = try presentView(configuration: .requireAuth())
    app.submitButton.tap()

    let stubOps = try viewModelOperations()
    XCTAssertTrue(stubOps.submitCalled)
    XCTAssertFalse(stubOps.cancelCalled)
}

func testNavigationToDetailView() async throws {
    let app = try presentView()
    app.itemRow.tap()

    XCTAssertTrue(app.detailView.exists)
}