Check whether the entity definition has a type

Fixes #5078

core/src/main/java/org/geysermc/geyser/util/EntityUtils.java

@@ -27,6 +27,8 @@ package org.geysermc.geyser.util;
 
 import java.util.Locale;
 import net.kyori.adventure.key.Key;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.math.vector.Vector3f;
 import org.cloudburstmc.protocol.bedrock.data.GameType;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
@@ -292,22 +294,27 @@ public final class EntityUtils {
         };
     }
 
-    private static String translatedEntityName(String namespace, String name, GeyserSession session) {
-        // MinecraftLocale would otherwise invoke getBootstrap (which doesn't exist) and create some folders
+    private static String translatedEntityName(@NonNull String namespace, @NonNull String name, @NonNull GeyserSession session) {
+        // MinecraftLocale would otherwise invoke getBootstrap (which doesn't exist) and create some folders,
+        // so use the default fallback value as used in Minecraft Java
         if (EnvironmentUtils.isUnitTesting) {
             return "entity." + namespace + "." + name;
         }
         return MinecraftLocale.getLocaleString("entity." + namespace + "." + name, session.locale());
     }
 
-    public static String translatedEntityName(Key type, GeyserSession session) {
+    public static String translatedEntityName(@NonNull Key type, @NonNull GeyserSession session) {
         return translatedEntityName(type.namespace(), type.value(), session);
     }
 
-    public static String translatedEntityName(EntityType type, GeyserSession session) {
+    public static String translatedEntityName(@Nullable EntityType type, @NonNull GeyserSession session) {
         if (type == EntityType.PLAYER) {
             return "Player"; // the player's name is always shown instead
         }
+        // default fallback value as used in Minecraft Java
+        if (type == null) {
+            return "entity.unregistered_sadface";
+        }
         // this works at least with all 1.20.5 entities, except the killer bunny since that's not an entity type.
         String typeName = type.name().toLowerCase(Locale.ROOT);
         return translatedEntityName("minecraft", typeName, session);

core/src/test/java/org/geysermc/geyser/scoreboard/network/ScoreboardIssueTests.java

@@ -28,16 +28,25 @@ package org.geysermc.geyser.scoreboard.network;
 import static org.geysermc.geyser.scoreboard.network.util.AssertUtils.assertNextPacketType;
 import static org.geysermc.geyser.scoreboard.network.util.GeyserMockContextScoreboard.mockContextScoreboard;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import org.cloudburstmc.protocol.bedrock.packet.AddEntityPacket;
 import org.cloudburstmc.protocol.bedrock.packet.RemoveEntityPacket;
+import org.geysermc.geyser.entity.type.living.monster.EnderDragonPartEntity;
+import org.geysermc.geyser.session.cache.EntityCache;
 import org.geysermc.geyser.translator.protocol.java.entity.JavaRemoveEntitiesTranslator;
 import org.geysermc.geyser.translator.protocol.java.entity.spawn.JavaAddExperienceOrbTranslator;
 import org.geysermc.mcprotocollib.protocol.packet.ingame.clientbound.entity.ClientboundRemoveEntitiesPacket;
 import org.geysermc.mcprotocollib.protocol.packet.ingame.clientbound.entity.spawn.ClientboundAddExperienceOrbPacket;
 import org.junit.jupiter.api.Test;
 
-public class TeamIdentifierTest {
+/**
+ * Tests that don't fit in a larger system (e.g. sidebar objective) that were reported on GitHub
+ */
+public class ScoreboardIssueTests {
+    /**
+     * Test for <a href="https://github.com/GeyserMC/Geyser/issues/5075">#5075</a>
+     */
     @Test
     void entityWithoutUuid() {
         // experience orbs are the only known entities without an uuid, see Entity#teamIdentifier for more info
@@ -50,6 +59,10 @@ public class TeamIdentifierTest {
             // because the entity would be registered and deregistered to the scoreboard.
             assertDoesNotThrow(() -> {
                 context.translate(addExperienceOrbTranslator, new ClientboundAddExperienceOrbPacket(2, 0, 0, 0, 1));
+
+                String displayName = context.mockOrSpy(EntityCache.class).getEntityByJavaId(2).getDisplayName();
+                assertEquals("entity.minecraft.experience_orb", displayName);
+
                 context.translate(removeEntitiesTranslator, new ClientboundRemoveEntitiesPacket(new int[] { 2 }));
             });
 
@@ -58,4 +71,23 @@ public class TeamIdentifierTest {
             assertNextPacketType(context, RemoveEntityPacket.class);
         });
     }
+
+    /**
+     * Test for <a href="https://github.com/GeyserMC/Geyser/issues/5078">#5078</a>
+     */
+    @Test
+    void entityWithoutType() {
+        // dragon entity parts are an entity in Geyser, but do not have an entity type
+        mockContextScoreboard(context -> {
+            // EntityUtils#translatedEntityName used to not take null EntityType's into account,
+            // so it used to throw an exception
+            assertDoesNotThrow(() -> {
+                // dragon entity parts are not spawned using a packet, so we manually create an instance
+                var dragonHeadPart = new EnderDragonPartEntity(context.session(), 2, 2, 1, 1);
+
+                String displayName = dragonHeadPart.getDisplayName();
+                assertEquals("entity.unregistered_sadface", displayName);
+            });
+        });
+    }
 }