axiom-xctest-automation

XCUITest 自动化模式

使用 XCUITest 编写可靠、易于维护的 UI 测试的全面指南。

核心原则

可靠的 UI 测试需要具备以下三点：

1. 稳定的元素标识（accessibilityIdentifier）
2. 基于条件的等待（绝不使用硬编码的 sleep）
3. 清晰的测试隔离（不共享状态）

元素标识

无障碍标识符模式

务必为测试关键元素使用 accessibilityIdentifier。

// SwiftUI
Button("Login") { ... }
    .accessibilityIdentifier("loginButton")

TextField("Email", text: $email)
    .accessibilityIdentifier("emailTextField")

// UIKit
loginButton.accessibilityIdentifier = "loginButton"
emailTextField.accessibilityIdentifier = "emailTextField"

查询选择指南

摘自 WWDC 2025-344《录制 UI 自动化》：

1. 本地化字符串会变化 → 改用 accessibilityIdentifier
2. 视图嵌套层级较深 → 使用尽可能简短的查询
3. 动态内容 → 使用通用查询或标识符

// BAD - Fragile queries
app.buttons["Login"]  // Breaks with localization
app.tables.cells.element(boundBy: 0).buttons.firstMatch  // Too specific

// GOOD - Stable queries
app.buttons["loginButton"]  // Uses identifier
app.tables.cells.containing(.staticText, identifier: "itemTitle").firstMatch

等待策略

切勿使用 sleep()

// BAD - Hardcoded wait
sleep(5)
XCTAssertTrue(app.buttons["submit"].exists)

// GOOD - Condition-based wait
let submitButton = app.buttons["submit"]
XCTAssertTrue(submitButton.waitForExistence(timeout: 5))

等待模式

// Wait for element to appear
func waitForElement(_ element: XCUIElement, timeout: TimeInterval = 10) -> Bool {
    element.waitForExistence(timeout: timeout)
}

// Wait for element to disappear
func waitForElementToDisappear(_ element: XCUIElement, timeout: TimeInterval = 10) -> Bool {
    let predicate = NSPredicate(format: "exists == false")
    let expectation = XCTNSPredicateExpectation(predicate: predicate, object: element)
    let result = XCTWaiter.wait(for: [expectation], timeout: timeout)
    return result == .completed
}

// Wait for element to be hittable (visible AND enabled)
func waitForElementHittable(_ element: XCUIElement, timeout: TimeInterval = 10) -> Bool {
    let predicate = NSPredicate(format: "isHittable == true")
    let expectation = XCTNSPredicateExpectation(predicate: predicate, object: element)
    let result = XCTWaiter.wait(for: [expectation], timeout: timeout)
    return result == .completed
}

// Wait for text to appear anywhere
func waitForText(_ text: String, timeout: TimeInterval = 10) -> Bool {
    app.staticTexts[text].waitForExistence(timeout: timeout)
}

异步操作

// Wait for network response
func waitForNetworkResponse() {
    let loadingIndicator = app.activityIndicators["loadingIndicator"]

    // Wait for loading to start
    _ = loadingIndicator.waitForExistence(timeout: 5)

    // Wait for loading to finish
    _ = waitForElementToDisappear(loadingIndicator, timeout: 30)
}

测试结构

设置和清理

class LoginTests: XCTestCase {
    var app: XCUIApplication!

    override func setUpWithError() throws {
        continueAfterFailure = false
        app = XCUIApplication()

        // Reset app state for clean test
        app.launchArguments = ["--uitesting", "--reset-state"]
        app.launchEnvironment = ["DISABLE_ANIMATIONS": "1"]
        app.launch()
    }

    override func tearDownWithError() throws {
        // Capture screenshot on failure
        if testRun?.failureCount ?? 0 > 0 {
            let screenshot = XCUIScreen.main.screenshot()
            let attachment = XCTAttachment(screenshot: screenshot)
            attachment.name = "Failure Screenshot"
            attachment.lifetime = .keepAlways
            add(attachment)
        }
        app.terminate()
    }
}

测试方法模式

func testLoginWithValidCredentials() throws {
    // ARRANGE - Navigate to login screen
    let loginButton = app.buttons["showLoginButton"]
    XCTAssertTrue(loginButton.waitForExistence(timeout: 5))
    loginButton.tap()

    // ACT - Enter credentials and submit
    let emailField = app.textFields["emailTextField"]
    XCTAssertTrue(emailField.waitForExistence(timeout: 5))
    emailField.tap()
    emailField.typeText("[email protected]")

    let passwordField = app.secureTextFields["passwordTextField"]
    passwordField.tap()
    passwordField.typeText("password123")

    app.buttons["loginSubmitButton"].tap()

    // ASSERT - Verify successful login
    let welcomeLabel = app.staticTexts["welcomeLabel"]
    XCTAssertTrue(welcomeLabel.waitForExistence(timeout: 10))
    XCTAssertTrue(welcomeLabel.label.contains("Welcome"))
}

常见交互

文本输入

// Clear and type
let textField = app.textFields["emailTextField"]
textField.tap()
textField.clearText()  // Custom extension
textField.typeText("[email protected]")

// Extension to clear text
extension XCUIElement {
    func clearText() {
        guard let stringValue = value as? String else { return }
        tap()
        let deleteString = String(repeating: XCUIKeyboardKey.delete.rawValue, count: stringValue.count)
        typeText(deleteString)
    }
}

滚动

// Scroll until element is visible
func scrollToElement(_ element: XCUIElement, in scrollView: XCUIElement) {
    while !element.isHittable {
        scrollView.swipeUp()
    }
}

// Scroll to specific element
let targetCell = app.tables.cells["targetItem"]
let table = app.tables.firstMatch
scrollToElement(targetCell, in: table)
targetCell.tap()

警告框和工作表

// Handle system alert
addUIInterruptionMonitor(withDescription: "Permission Alert") { alert in
    if alert.buttons["Allow"].exists {
        alert.buttons["Allow"].tap()
        return true
    }
    return false
}
app.tap() // Trigger the monitor

// Handle app alert
let alert = app.alerts["Error"]
if alert.waitForExistence(timeout: 5) {
    alert.buttons["OK"].tap()
}

收起键盘

// Dismiss keyboard
if app.keyboards.count > 0 {
    app.toolbars.buttons["Done"].tap()
    // Or tap outside
    // app.tap()
}

测试计划

多配置测试

测试计划支持使用不同配置运行相同的测试：

{
  "configurations" : [
    {
      "name" : "English",
      "options" : {
        "language" : "en",
        "region" : "US"
      }
    },
    {
      "name" : "Spanish",
      "options" : {
        "language" : "es",
        "region" : "ES"
      }
    },
    {
      "name" : "Dark Mode",
      "options" : {
        "userInterfaceStyle" : "dark"
      }
    }
  ],
  "testTargets" : [
    {
      "target" : {
        "containerPath" : "container:MyApp.xcodeproj",
        "identifier" : "MyAppUITests",
        "name" : "MyAppUITests"
      }
    }
  ]
}

使用测试计划运行

xcodebuild test \
  -scheme "MyApp" \
  -testPlan "MyTestPlan" \
  -destination "platform=iOS Simulator,name=iPhone 16" \
  -resultBundlePath /tmp/results.xcresult

CI/CD 集成

并行执行测试

xcodebuild test \
  -scheme "MyAppUITests" \
  -destination "platform=iOS Simulator,name=iPhone 16" \
  -parallel-testing-enabled YES \
  -maximum-parallel-test-targets 4 \
  -resultBundlePath /tmp/results.xcresult

重试失败的测试

xcodebuild test \
  -scheme "MyAppUITests" \
  -destination "platform=iOS Simulator,name=iPhone 16" \
  -retry-tests-on-failure \
  -test-iterations 3 \
  -resultBundlePath /tmp/results.xcresult

代码覆盖率

xcodebuild test \
  -scheme "MyAppUITests" \
  -destination "platform=iOS Simulator,name=iPhone 16" \
  -enableCodeCoverage YES \
  -resultBundlePath /tmp/results.xcresult

# Export coverage report
xcrun xcresulttool export coverage \
  --path /tmp/results.xcresult \
  --output-path /tmp/coverage

调试失败的测试

截取屏幕截图

// Manual screenshot capture
let screenshot = app.screenshot()
let attachment = XCTAttachment(screenshot: screenshot)
attachment.name = "Before Login"
attachment.lifetime = .keepAlways
add(attachment)

录制视频

在测试计划或方案中启用：

"systemAttachmentLifetime" : "keepAlways",
"userAttachmentLifetime" : "keepAlways"

打印元素层级结构

// Debug: Print all elements
print(app.debugDescription)

// Debug: Print specific container
print(app.tables.firstMatch.debugDescription)

应避免的反模式

1. 硬编码延迟

// BAD
sleep(5)
button.tap()

// GOOD
XCTAssertTrue(button.waitForExistence(timeout: 5))
button.tap()

2. 基于索引的查询

// BAD - Breaks if order changes
app.tables.cells.element(boundBy: 0)

// GOOD - Uses identifier
app.tables.cells["firstItem"]

3. 测试之间共享状态

// BAD - Tests depend on order
func test1_CreateItem() { ... }
func test2_EditItem() { ... }  // Depends on test1

// GOOD - Independent tests
func testCreateItem() {
    // Creates own item
}
func testEditItem() {
    // Creates item, then edits
}

4. 测试实现细节

// BAD - Tests internal structure
XCTAssertEqual(app.tables.cells.count, 10)

// GOOD - Tests user-visible behavior
XCTAssertTrue(app.staticTexts["10 items"].exists)

录制 UI 自动化（Xcode 26+）

摘自 WWDC 2025-344：

1. 录制 — 在 Xcode 中录制交互（Debug → Record UI Automation）
2. 重放 — 通过测试计划在不同设备、语言和配置下运行
3. 查看 — 在测试报告中观看录制的视频

改进录制的代码

// RECORDED (may be fragile)
app.buttons["Login"].tap()

// ENHANCED (stable)
let loginButton = app.buttons["loginButton"]
XCTAssertTrue(loginButton.waitForExistence(timeout: 5))
loginButton.tap()

资源

WWDC：2025-344、2024-10206、2023-10175、2019-413

文档：/xctest/xcuiapplication、/xctest/xcuielement、/xctest/xcuielementquery

技能：axiom-ui-testing、axiom-swift-testing