HermesAssert

HermesAssert provides fluent assertions for verifying Hermes window behavior. All assertions throw HermesAssertionException on failure with descriptive messages.

Window Lifecycle

Verify the window went through expected lifecycle states:

HermesAssert.WasInitialized(backend);  // Backend was initialized
HermesAssert.WasShown(backend);        // Window was shown
HermesAssert.WasClosed(backend);       // Window was closed

Window State

Maximize/Restore Events

// Check if events occurred during the test
HermesAssert.WasMaximized(recording);  // Maximized event was raised
HermesAssert.WasRestored(recording);   // Restored event was raised

Current State

// Check current window state
HermesAssert.IsMaximized(backend);     // Window is currently maximized
HermesAssert.IsNotMaximized(backend);  // Window is not maximized

Window Properties

HermesAssert.HasTitle(backend, "My App");
HermesAssert.HasSize(backend, 1024, 768);
HermesAssert.HasPosition(backend, 100, 100);

Navigation

Verify URL navigation:

// Exact URL match
HermesAssert.NavigatedTo(recording, "https://example.com");

// Pattern match (contains)
HermesAssert.NavigatedToPattern(recording, "example");

Web Messages

Messages Sent to JavaScript

// Exact message match
HermesAssert.SentWebMessage(recording, """{"type":"response"}""");

// Pattern match (contains)
HermesAssert.SentWebMessageMatching(recording, "response");

Messages Received from JavaScript

// Exact message match
HermesAssert.ReceivedWebMessage(recording, """{"type":"request"}""");

// Pattern match (contains)
HermesAssert.ReceivedWebMessageMatching(recording, "request");

Custom Titlebar Drag Regions

Verify drag region interactions:

// Generic drag action
HermesAssert.DetectedDragAction(recording, "drag");

// Specific actions
HermesAssert.DetectedDragRegionClick(recording);       // Single click
HermesAssert.DetectedDragRegionDoubleClick(recording); // Double-click
HermesAssert.DetectedNonDragRegionClick(recording);    // Non-drag area

Method Calls

Verify backend methods were called:

HermesAssert.MethodWasCalled(recording, "NavigateToUrl");
HermesAssert.MethodWasNotCalled(recording, "NavigateToString");

Events

Verify events were raised:

HermesAssert.EventWasRaised(recording, "Resized");
HermesAssert.EventWasNotRaised(recording, "FocusOut");

Custom Schemes

Verify custom URL schemes were registered:

HermesAssert.CustomSchemeRegistered(backend, "app");

Complete API Reference

Lifecycle Assertions

Method	Parameters	Description
WasInitialized	backend	Assert backend was initialized
WasShown	backend	Assert window was shown
WasClosed	backend	Assert window was closed

State Assertions

Method	Parameters	Description
WasMaximized	recording	Assert Maximized event occurred
WasRestored	recording	Assert Restored event occurred
IsMaximized	backend	Assert currently maximized
IsNotMaximized	backend	Assert not maximized
HasSize	backend, width, height	Assert size matches
HasPosition	backend, x, y	Assert position matches
HasTitle	backend, title	Assert title matches

Navigation Assertions

Method	Parameters	Description
NavigatedTo	recording, url	Assert exact URL navigation
NavigatedToPattern	recording, pattern	Assert URL contains pattern

Web Message Assertions

Method	Parameters	Description
SentWebMessage	recording, message	Assert exact message sent
SentWebMessageMatching	recording, pattern	Assert sent message contains pattern
ReceivedWebMessage	recording, message	Assert exact message received
ReceivedWebMessageMatching	recording, pattern	Assert received message contains pattern

Drag Region Assertions

Method	Parameters	Description
DetectedDragAction	recording, action	Assert specific drag action
DetectedDragRegionClick	recording	Assert drag region click
DetectedDragRegionDoubleClick	recording	Assert drag region double-click
DetectedNonDragRegionClick	recording	Assert non-drag region click

Call/Event Assertions

Method	Parameters	Description
MethodWasCalled	recording, methodName	Assert method was called
MethodWasNotCalled	recording, methodName	Assert method was not called
EventWasRaised	recording, eventName	Assert event was raised
EventWasNotRaised	recording, eventName	Assert event was not raised

Scheme Assertions

Method	Parameters	Description
CustomSchemeRegistered	backend, scheme	Assert scheme was registered

Error Messages

Failed assertions provide detailed messages:

Expected window title 'My App', but was 'Other App'.

Expected navigation to 'https://example.com', but it never occurred.
Navigations: [https://other.com]

Expected web message containing 'response' to be sent, but none matched.
Sent messages: ["error", "timeout"]

See Also

• TestableHermesWindow — Test wrapper
• RecordingWindowBackend — Mock backend
• Testing Examples — Common patterns