Add test for LtsTimelineClassic EventGraphic.cpp

- Add test_eventgraphic.cpp with 3 tests
- Follow policy naming convention

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

qt6-after/qt6-migrated-benchmark/tests/test_eventgraphic.cpp

@@ -0,0 +1,59 @@
+#include "Lts/Common/LtsTimelineClassic/Event.h"
+#include "Lts/Common/LtsTimelineClassic/EventGraphic.h"
+
+#include <QPainter>
+#include <QRect>
+#include <gtest/gtest.h>
+
+namespace LtsTimelineClassic
+{
+
+class EventGraphicTest : public ::testing::Test
+{
+  protected:
+    void SetUp() override {}
+
+    void TearDown() override {}
+};
+
+TEST(EventGraphicTest, ConstructorCreatesEventGraphic)
+{
+    Event event(0, 100, Qt::red);
+    EventGraphic graphic(&event);
+
+    EXPECT_FALSE(graphic.isMultipleEvent());
+    EXPECT_EQ(graphic.eventList().size(), 1);
+}
+
+TEST(EventGraphicTest, AddEventMakesItMultiple)
+{
+    Event event1(0, 100, Qt::red);
+    Event event2(50, 100, Qt::blue);
+    EventGraphic graphic(&event1);
+
+    EXPECT_FALSE(graphic.isMultipleEvent());
+
+    graphic.addEvent(&event2);
+
+    EXPECT_TRUE(graphic.isMultipleEvent());
+    EXPECT_EQ(graphic.eventList().size(), 2);
+}
+
+TEST(EventGraphicTest, AddEventListMakesItMultiple)
+{
+    Event event1(0, 100, Qt::red);
+    Event event2(50, 100, Qt::blue);
+    Event event3(100, 100, Qt::green);
+    EventGraphic graphic(&event1);
+
+    QVector<Event*> additionalEvents;
+    additionalEvents.append(&event2);
+    additionalEvents.append(&event3);
+
+    graphic.addEventList(additionalEvents);
+
+    EXPECT_TRUE(graphic.isMultipleEvent());
+    EXPECT_EQ(graphic.eventList().size(), 3);
+}
+
+} // namespace LtsTimelineClassic