Add basic tests for event nodes

Signed-off-by: TheMode <themode@outlook.fr>

src/test/java/event/EventNodeTest.java

@@ -0,0 +1,69 @@
+package event;
+
+import net.minestom.server.event.Event;
+import net.minestom.server.event.EventListener;
+import net.minestom.server.event.EventNode;
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class EventNodeTest {
+
+    class EventTest implements Event {
+    }
+
+    @Test
+    public void testCall() {
+        var node = EventNode.all("main");
+        AtomicBoolean result = new AtomicBoolean(false);
+        var listener = EventListener.of(EventTest.class, eventTest -> result.set(true));
+        node.addListener(listener);
+        assertFalse(result.get(), "The event should not be called before the call");
+        node.call(new EventTest());
+        assertTrue(result.get(), "The event should be called after the call");
+
+        // Test removal
+        result.set(false);
+        node.removeListener(listener);
+        node.call(new EventTest());
+        assertFalse(result.get(), "The event should not be called after the removal");
+    }
+
+    @Test
+    public void testChildren() {
+        var node = EventNode.all("main");
+        AtomicInteger result = new AtomicInteger(0);
+        var child1 = EventNode.all("child1").setPriority(1)
+                .addListener(EventTest.class, eventTest -> {
+                    assertEquals(0, result.get(), "child1 should be called before child2");
+                    result.set(1);
+                });
+        var child2 = EventNode.all("child2").setPriority(2)
+                .addListener(EventTest.class, eventTest -> {
+                    assertEquals(1, result.get(), "child2 should be called after child1");
+                    result.set(2);
+                });
+        node.addChild(child1);
+        node.addChild(child2);
+        assertEquals(node.getChildren().size(), 2, "The node should have 2 children");
+        node.call(new EventTest());
+        assertEquals(2, result.get(), "The event should be called after the call");
+
+        // Test removal
+        result.set(0);
+        node.removeChild(child2);
+        assertEquals(node.getChildren().size(), 1, "The node should have 1 child");
+        node.call(new EventTest());
+        assertEquals(1, result.get(), "child2 should has been removed");
+
+        result.set(0);
+        node.removeChild(child1);
+        node.call(new EventTest());
+        assertTrue(node.getChildren().isEmpty(), "The node should have no child left");
+        assertEquals(0, result.get(), "The event should not be called after the removal");
+    }
+
+}