Test Coverage Phase 3: XCUITest Implementation

[schuyler]

Overview

Phase 3 of the test coverage improvement plan from plans/xcuitest.md. Targeted UI tests for critical user workflows.

Target: v3000.1.x or v3001.0.0 (can be written in Swift as part of port)

Depends on:

• Test Coverage Phase 2: Refactoring for Testability #198 (Phase 2 refactoring)
• Migrate from WebView to WKWebView #111 (WKWebView migration - for stable WebView testing)

XCUITest Target Setup

New Target: MacDownUITests

Configuration:

• Test target with host application
• Accessibility identifiers added to key UI elements
• Test data fixtures (sample markdown files)

Critical Path Tests (8-10 tests max)

Keep the UI test suite small and focused on high-value scenarios.

BasicWorkflowUITests.swift

class BasicWorkflowUITests: XCTestCase {
    func testCreateEditExportWorkflow() {
        // New doc → type markdown → preview updates → export
    }
    
    func testFileOpenSaveWorkflow() {
        // Open file → modify → save → verify disk
    }
    
    func testPreviewUpdatesInRealTime() {
        // Type in editor → preview renders
    }
}

ScrollSyncUITests.swift

class ScrollSyncUITests: XCTestCase {
    func testScrollEditorUpdatesPreview() {
        // Issue #39: Scroll editor → preview follows
    }
    
    func testScrollSyncWithImages() {
        // Long doc with images → scroll stays synced
    }
    
    func testScrollPositionRestoration() {
        // Scroll → close → reopen → position restored
    }
}

ExportUITests.swift

class ExportUITests: XCTestCase {
    func testExportHTML() {
        // Menu → Export → file created
    }
    
    func testCopyAsHTML() {
        // Menu → Copy as HTML → clipboard has HTML
    }
}

PreferencesUITests.swift

class PreferencesUITests: XCTestCase {
    func testThemeChange() {
        // Prefs → change theme → preview updates
    }
    
    func testSyntaxHighlightingToggle() {
        // Prefs → toggle highlighting → preview changes
    }
}

Page Object Pattern

class EditorPage {
    let app: XCUIApplication
    var textView: XCUIElement { app.textViews["markdown-editor"] }
    
    func typeMarkdown(_ text: String) {
        textView.click()
        textView.typeText(text)
    }
}

class PreviewPage {
    let app: XCUIApplication
    var webView: XCUIElement { app.webViews["preview-pane"] }
    
    func waitForRender() {
        webView.waitForExistence(timeout: 2)
    }
    
    func containsText(_ text: String) -> Bool {
        return webView.staticTexts[text].exists
    }
}

Test Data Fixtures

MacDownUITests/
  Fixtures/
    simple.md
    with-images.md
    long-document.md
    math-equations.md

Accessibility Identifiers Required

Add to codebase before XCUITests:

• markdown-editor on MPEditorView
• preview-pane on WebView/WKWebView
• document-window on main window
• Menu item identifiers as needed

Success Criteria

• XCUITest target created and builds
• 8-10 focused UI tests implemented
• Tests complete in < 10 minutes
• Test flakiness < 5%
• Page objects provide reusable abstractions

Risks and Mitigations

Risk	Mitigation
XCUITest flakiness	Use waitForExistence(), generous timeouts, retry logic
WebView testing unreliable	Ensure WKWebView migration (#111) complete first
Slow test execution	Keep test count low, parallelize where possible

Related

• plans/xcuitest.md - Full technical design
• Test Coverage Phase 1: Enhanced Unit Tests #197 - Phase 1 (prerequisite)
• Test Coverage Phase 2: Refactoring for Testability #198 - Phase 2 (prerequisite)
• Migrate from WebView to WKWebView #111 - WKWebView migration (prerequisite for stable testing)