Add integration test. Run with ./gradlew runIntegrationTest

src/integration-test/java/com/replaymod/replay/overlay/OverlayGui.java

@@ -0,0 +1,33 @@
+package com.replaymod.replay.overlay;
+
+import com.replaymod.core.AbstractTask;
+import com.replaymod.core.CompositeTask;
+import com.replaymod.core.Task;
+import com.replaymod.replay.gui.overlay.GuiReplayOverlay;
+import org.lwjgl.input.Keyboard;
+
+public class OverlayGui {
+    public static Task whileOpened(Task...tasks) {
+        Task[] nTasks = new Task[tasks.length + 2];
+        System.arraycopy(tasks, 0, nTasks, 1, tasks.length);
+        nTasks[0] = new Open();
+        nTasks[tasks.length + 1] = new Close();
+        return new CompositeTask(nTasks);
+    }
+
+    public static class Open extends AbstractTask {
+        @Override
+        protected void init() {
+            press(Keyboard.KEY_T);
+            expectGui(GuiReplayOverlay.class, done -> future.set(null));
+        }
+    }
+
+    public static class Close extends AbstractTask {
+        @Override
+        protected void init() {
+            press(Keyboard.KEY_ESCAPE);
+            expectGuiClosed(() -> future.set(null));
+        }
+    }
+}