test: remove old DeprecationTest; replace ReuseEngineTest

src/main/java/org/terasology/moduletestingenvironment/fixtures/DummyComponent.java

@@ -6,10 +6,12 @@
 import org.terasology.gestalt.entitysystem.component.Component;
 
 public class DummyComponent implements Component<DummyComponent> {
-    public boolean dummy = false;
+    public boolean eventReceived = false;
+    public String name;
 
     @Override
     public void copyFrom(DummyComponent other) {
-        this.dummy = other.dummy;
+        eventReceived = other.eventReceived;
+        name = other.name;
     }
 }

src/main/java/org/terasology/moduletestingenvironment/fixtures/DummyEvent.java

@@ -1,22 +1,7 @@
-/*
- * Copyright 2017 MovingBlocks
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2021 The Terasology Foundation
+// SPDX-License-Identifier: Apache-2.0
 package org.terasology.moduletestingenvironment.fixtures;
 
 import org.terasology.engine.entitySystem.event.Event;
 
-public class DummyEvent implements Event {
-    public boolean dummy = false;
-}
+public class DummyEvent implements Event { }

src/main/java/org/terasology/moduletestingenvironment/fixtures/DummySystem.java

@@ -1,18 +1,5 @@
-/*
- * Copyright 2017 MovingBlocks
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
+// Copyright 2021 The Terasology Foundation
+// SPDX-License-Identifier: Apache-2.0
 package org.terasology.moduletestingenvironment.fixtures;
 
 import org.terasology.engine.entitySystem.entity.EntityRef;
@@ -27,7 +14,7 @@
 public class DummySystem extends BaseComponentSystem {
     @ReceiveEvent
     public void onDummyEvent(DummyEvent event, EntityRef entity, DummyComponent component) {
-        component.dummy = true;
+        component.eventReceived = true;
         entity.saveComponent(component);
     }
 }

src/test/java/org/terasology/moduletestingenvironment/ComponentSystemTest.java

@@ -8,10 +8,10 @@
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.terasology.engine.entitySystem.entity.EntityManager;
 import org.terasology.engine.entitySystem.entity.EntityRef;
+import org.terasology.engine.registry.In;
 import org.terasology.moduletestingenvironment.extension.Dependencies;
 import org.terasology.moduletestingenvironment.fixtures.DummyComponent;
 import org.terasology.moduletestingenvironment.fixtures.DummyEvent;
-import org.terasology.engine.registry.In;
 
 @Tag("MteTest")
 @ExtendWith(MTEExtension.class)
@@ -24,6 +24,6 @@ public class ComponentSystemTest {
     public void simpleEventTest() {
         EntityRef entity = entityManager.create(new DummyComponent());
         entity.send(new DummyEvent());
-        Assertions.assertTrue(entity.getComponent(DummyComponent.class).dummy);
+        Assertions.assertTrue(entity.getComponent(DummyComponent.class).eventReceived);
     }
 }

src/test/java/org/terasology/moduletestingenvironment/IsolatedEngineTest.java

@@ -5,22 +5,28 @@
 
 import com.google.common.collect.Sets;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.MethodOrderer;
+import org.junit.jupiter.api.Order;
+import org.junit.jupiter.api.Tag;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestMethodOrder;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.terasology.engine.entitySystem.entity.EntityManager;
 import org.terasology.engine.entitySystem.entity.EntityRef;
+import org.terasology.engine.registry.In;
 import org.terasology.moduletestingenvironment.extension.Dependencies;
 import org.terasology.moduletestingenvironment.fixtures.DummyComponent;
 import org.terasology.moduletestingenvironment.fixtures.DummyEvent;
-import org.terasology.engine.registry.In;
 
 import java.util.Set;
 
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+@Tag("MteTest")
 @ExtendWith(IsolatedMTEExtension.class)
 @Dependencies({"engine", "ModuleTestingEnvironment"})
+@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
 public class IsolatedEngineTest {
     private final Set<EntityManager> entityManagerSet = Sets.newHashSet();
     private EntityRef entity;
@@ -34,21 +40,23 @@ public void prepareEntityForTest() {
     }
 
     @Test
+    @Order(1)
     public void someTest() {
         // make sure we don't reuse the EntityManager
         assertFalse(entityManagerSet.contains(entityManager));
         entityManagerSet.add(entityManager);
 
         entity.send(new DummyEvent());
-        assertTrue(entity.getComponent(DummyComponent.class).dummy);
+        assertTrue(entity.getComponent(DummyComponent.class).eventReceived);
     }
 
     @Test
+    @Order(2)
     public void someOtherTest() {
         // make sure we don't reuse the EntityManager
         assertFalse(entityManagerSet.contains(entityManager));
         entityManagerSet.add(entityManager);
 
-        assertFalse(entity.getComponent(DummyComponent.class).dummy);
+        assertFalse(entity.getComponent(DummyComponent.class).eventReceived);
     }
 }

src/test/java/org/terasology/moduletestingenvironment/MTEExtensionTestWithPerMethodLifecycle.java

@@ -0,0 +1,95 @@
+// Copyright 2021 The Terasology Foundation
+// SPDX-License-Identifier: Apache-2.0
+
+package org.terasology.moduletestingenvironment;
+
+import com.google.common.collect.Lists;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.MethodOrderer;
+import org.junit.jupiter.api.Order;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInfo;
+import org.junit.jupiter.api.TestInstance;
+import org.junit.jupiter.api.TestMethodOrder;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.terasology.engine.entitySystem.entity.EntityManager;
+import org.terasology.engine.entitySystem.entity.EntityRef;
+import org.terasology.engine.registry.In;
+import org.terasology.moduletestingenvironment.fixtures.DummyComponent;
+import org.terasology.moduletestingenvironment.fixtures.DummyEvent;
+
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * Ensure a test class with a per-method Jupiter lifecycle can share an engine between tests.
+ */
+@Tag("MteTest")
+@ExtendWith(MTEExtension.class)
+@TestInstance(TestInstance.Lifecycle.PER_METHOD)  // The default, but here for explicitness.
+@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
+public class MTEExtensionTestWithPerMethodLifecycle {
+    // java 8 doesn't have ConcurrentSet
+    @SuppressWarnings("checkstyle:constantname")
+    private static final ConcurrentMap<String, Integer> seenNames = new ConcurrentHashMap<>();
+
+    @In
+    public EntityManager entityManager;
+
+    @BeforeAll
+    public static void createEntity(EntityManager entityManager, TestInfo testInfo) {
+        // Create some entity to be shared by all the tests.
+        EntityRef entity = entityManager.create(new DummyComponent());
+
+        // Do some stuff to configure it.
+        entity.send(new DummyEvent());
+
+        entity.updateComponent(DummyComponent.class, component -> {
+            // Mark with something unique (and not reliant on the entity id system)
+            component.name = testInfo.getDisplayName() + "#" + UUID.randomUUID();
+            return component;
+        });
+    }
+
+    @Test
+    @Order(1)
+    public void firstTestFindsThings() {
+        List<EntityRef> entities = Lists.newArrayList(entityManager.getEntitiesWith(DummyComponent.class));
+        // There should be one entity, created by the @BeforeAll method
+        assertEquals(1, entities.size());
+
+        DummyComponent component = entities.get(0).getComponent(DummyComponent.class);
+        assertTrue(component.eventReceived);
+
+        // Remember that a test has seen this one.
+        assertNotNull(component.name);
+        assertFalse(seenNames.containsKey(component.name));
+        seenNames.put(component.name, 1);
+    }
+
+    @Test
+    @Order(2)
+    public void thingsStillExistForSecondTest() {
+        List<EntityRef> entities = Lists.newArrayList(entityManager.getEntitiesWith(DummyComponent.class));
+        // There should be one entity, created by the @BeforeAll method
+        assertEquals(1, entities.size());
+
+        // Make sure that this is the same one that the first test saw.
+        DummyComponent component = entities.get(0).getComponent(DummyComponent.class);
+        assertTrue(component.eventReceived);
+        assertNotNull(component.name);
+        assertTrue(seenNames.containsKey(component.name), () ->
+                String.format("This is not the same entity as seen in the first test!%n"
+                        + "Current entity: %s%n"
+                        + "Previously seen: %s",
+                        component.name, seenNames.keySet()));
+    }
+}