Add XCUI expansion state and coverage tests

tests/NewEditor/CMakeLists.txt

@@ -100,6 +100,12 @@ set(NEW_EDITOR_STANDALONE_TEXT_ATLAS_PROVIDER_SOURCE
 set(NEW_EDITOR_HOSTED_PREVIEW_PRESENTER_HEADER
     ${CMAKE_SOURCE_DIR}/new_editor/src/XCUIBackend/XCUIHostedPreviewPresenter.h
 )
+set(NEW_EDITOR_WINDOW_UI_COMPOSITOR_HEADER
+    ${CMAKE_SOURCE_DIR}/new_editor/src/XCUIBackend/IWindowUICompositor.h
+)
+set(NEW_EDITOR_IMGUI_WINDOW_UI_COMPOSITOR_HEADER
+    ${CMAKE_SOURCE_DIR}/new_editor/src/XCUIBackend/ImGuiWindowUICompositor.h
+)
 set(NEW_EDITOR_NATIVE_BACKDROP_RENDERER_HEADER
     ${CMAKE_SOURCE_DIR}/new_editor/src/Rendering/MainWindowNativeBackdropRenderer.h
 )
@@ -265,6 +271,37 @@ else()
     message(STATUS "Skipping new_editor_xcui_hosted_preview_presenter_tests because presenter header or ImGui sources are missing.")
 endif()
 
+if(EXISTS "${NEW_EDITOR_WINDOW_UI_COMPOSITOR_HEADER}" AND
+   EXISTS "${NEW_EDITOR_IMGUI_WINDOW_UI_COMPOSITOR_HEADER}" AND
+   EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/test_imgui_window_ui_compositor.cpp")
+    add_executable(new_editor_imgui_window_ui_compositor_tests
+        test_imgui_window_ui_compositor.cpp
+    )
+
+    xcengine_configure_new_editor_test_target(new_editor_imgui_window_ui_compositor_tests)
+
+    target_link_libraries(new_editor_imgui_window_ui_compositor_tests
+        PRIVATE
+        XCEngine
+        GTest::gtest
+        GTest::gtest_main
+        user32
+        comdlg32
+    )
+
+    target_include_directories(new_editor_imgui_window_ui_compositor_tests PRIVATE
+        ${CMAKE_SOURCE_DIR}/engine/include
+        ${CMAKE_SOURCE_DIR}/new_editor/src
+        ${CMAKE_SOURCE_DIR}/editor/src
+        ${CMAKE_BINARY_DIR}/_deps/imgui-src
+        ${CMAKE_BINARY_DIR}/_deps/imgui-src/backends
+    )
+
+    xcengine_discover_new_editor_gtests(new_editor_imgui_window_ui_compositor_tests)
+else()
+    message(STATUS "Skipping new_editor_imgui_window_ui_compositor_tests because compositor headers or the test source are missing.")
+endif()
+
 if(EXISTS "${NEW_EDITOR_NATIVE_BACKDROP_RENDERER_HEADER}")
     add_executable(new_editor_native_backdrop_renderer_api_tests
         test_main_window_native_backdrop_renderer_api.cpp