test(core): add a test for BoxEventManager

core/src/test/java/net/okocraft/box/core/model/manager/event/BoxEventManagerTest.java

@@ -0,0 +1,41 @@
+package net.okocraft.box.core.model.manager.event;
+
+import net.okocraft.box.api.event.BoxEvent;
+import net.okocraft.box.test.shared.scheduler.ScheduledTask;
+import net.okocraft.box.test.shared.scheduler.TestScheduler;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.time.Duration;
+import java.util.concurrent.CompletableFuture;
+
+class BoxEventManagerTest {
+
+    @Test
+    void testInitializeAsyncCaller() {
+        var manager = BoxEventManager.create();
+        var event = new BoxEvent();
+
+        { // Checks if the EventManager#callAsync can be called without BoxScheduler
+            var future = new CompletableFuture<BoxEvent>();
+            manager.callAsync(event, future::complete);
+            Assertions.assertSame(event, future.join());
+        }
+
+        { // Checks if it calls an event async by BoxScheduler
+            var scheduler = new TestScheduler(true);
+            manager.initializeAsyncEventCaller(scheduler);
+
+            var future = new CompletableFuture<BoxEvent>();
+            manager.callAsync(event, future::complete);
+            scheduler.checkTask(task -> {
+                Assertions.assertEquals(task.delay(), Duration.ofSeconds(0));
+                Assertions.assertEquals(task.interval(), Duration.ofSeconds(0));
+                Assertions.assertEquals(task.type(), ScheduledTask.Type.ASYNC);
+            });
+            Assertions.assertSame(event, future.join());
+        }
+    }
+
+    // Other methods are just delegating to EventServiceProvider.
+}