TestableHermesWindow

TestableHermesWindow is the primary entry point for testing Hermes window behavior. It wraps a HermesWindow with a RecordingWindowBackend, providing fluent configuration and event simulation capabilities.

Creating a Test Window

// Basic creation
using var testWindow = new TestableHermesWindow();

// With custom backend
var backend = new RecordingWindowBackend { Platform = HermesPlatform.macOS };
using var testWindow = new TestableHermesWindow(backend);

Properties

Property	Type	Description
Window	HermesWindow	The underlying HermesWindow instance
Backend	RecordingWindowBackend	The mock backend for verification
Recording	WindowBackendRecording	Access to recorded interactions

Fluent Configuration

All configuration methods return this for chaining:

using var testWindow = new TestableHermesWindow()
    .SetTitle("My App")
    .SetSize(1024, 768)
    .SetPosition(100, 100)
    .Center()
    .SetResizable(true)
    .SetChromeless(false)
    .SetCustomTitleBar(true)
    .Load("https://example.com");

Window Properties

SetTitle(string title)           // Set window title
SetSize(int width, int height)   // Set initial size
SetPosition(int x, int y)        // Set initial position
Center()                         // Center on screen when shown
SetResizable(bool resizable)     // Enable/disable resize
SetChromeless(bool chromeless)   // Remove window chrome
SetCustomTitleBar(bool enabled)  // Enable custom titlebar mode
Maximize()                       // Start maximized
Minimize()                       // Start minimized

Content Loading

Load(string url)                 // Load URL in WebView
LoadHtml(string html)            // Load HTML content directly

Event Handlers

OnWebMessage(Action<string> handler)        // Messages from JavaScript
OnMaximized(Action handler)                 // Window maximized
OnRestored(Action handler)                  // Window restored
OnResized(Action<int, int> handler)         // Window resized (width, height)
OnMoved(Action<int, int> handler)           // Window moved (x, y)
OnClosing(Action handler)                   // Window closing

Lifecycle Methods

// Show the window (non-blocking in tests)
testWindow.Show();

// Show and wait for close (non-blocking in tests)
testWindow.WaitForClose();

// Close the window
testWindow.Close();

TIP

In test mode, Show() and WaitForClose() do not actually block. They record the operation and continue immediately.

Event Simulation

Simulate user interactions and system events:

// Web messages
testWindow.SimulateWebMessage("""{"type":"event","data":"test"}""");

// Window state
testWindow.SimulateResize(1920, 1080);
testWindow.SimulateMove(200, 100);
testWindow.SimulateMaximize();
testWindow.SimulateRestore();

// Focus
testWindow.SimulateFocusIn();
testWindow.SimulateFocusOut();

// Custom titlebar drag regions
testWindow.SimulateDragRegionClick();
testWindow.SimulateDragRegionDoubleClick();
testWindow.SimulateNonDragRegionClick();

Complete Example

[Fact]
public void Window_HandlesMaximizeRestoreCycle()
{
    var events = new List<string>();

    using var testWindow = new TestableHermesWindow()
        .SetTitle("Test App")
        .SetSize(800, 600)
        .OnMaximized(() => events.Add("maximized"))
        .OnRestored(() => events.Add("restored"));

    testWindow.Show();

    // Simulate maximize/restore cycle
    testWindow.SimulateMaximize();
    testWindow.SimulateRestore();

    // Verify events fired in order
    Assert.Equal(["maximized", "restored"], events);

    // Verify final state
    HermesAssert.IsNotMaximized(testWindow.Backend);
}

See Also

• RecordingWindowBackend — Direct backend access
• HermesAssert — Assertion helpers
• Testing Examples — Common patterns