Fix XP increase when restoring advancements on world switch

.gitignore

@@ -46,6 +46,10 @@ release.properties
 dependency-reduced-pom.xml
 buildNumber.properties
 
+ # Test artifacts
+database/
+database_backup/
+
  # Intellij
 *.iml
 *.java___jb_tmp___

src/main/java/com/wasteofplastic/invswitcher/Store.java

@@ -320,7 +320,15 @@ private void setFood(InventoryStorage store, Player player, String overworldName
 
     private void setAdvancements(InventoryStorage store, Player player, String overworldName) {
         // Advancements
-        store.getAdvancements(overworldName).forEach((k, v) -> {
+        Map<String, List<String>> advancements = store.getAdvancements(overworldName);
+        if (advancements.isEmpty()) {
+            return;
+        }
+        // Save current experience before granting advancements, because some advancements
+        // reward XP when their criteria are awarded, which would incorrectly increase the
+        // player's experience points.
+        int savedExp = getTotalExperience(player);
+        advancements.forEach((k, v) -> {
             Iterator<Advancement> it = Bukkit.advancementIterator();
             while (it.hasNext()) {
                 Advancement a = it.next();
@@ -330,7 +338,8 @@ private void setAdvancements(InventoryStorage store, Player player, String overw
                 }
             }
         });
-
+        // Restore experience to prevent advancement rewards from modifying it
+        setTotalExperience(player, savedExp);
     }
 
     public void removeFromCache(Player player) {

src/test/java/com/wasteofplastic/invswitcher/StoreTest.java

@@ -22,6 +22,7 @@
 import java.nio.file.Path;
 import java.util.Comparator;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
@@ -30,8 +31,11 @@
 import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
 import org.bukkit.World;
 import org.bukkit.World.Environment;
+import org.bukkit.advancement.Advancement;
+import org.bukkit.advancement.AdvancementProgress;
 import org.bukkit.attribute.AttributeInstance;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.Player;
@@ -200,6 +204,46 @@
         verify(player).setTotalExperience(0);
     }
 
+    /**
+     * Test that advancement grants during {@link Store#getInventory} do not modify the player's
+     * experience points. Some advancements reward XP when their criteria are awarded; the store
+     * must save and restore XP around the advancement grant step.
+     */
+    @Test
+    public void testGetInventoryAdvancementsPreservesExperience() {
+        sets.setAdvancements(true);
+        sets.setExperience(true);
+        sets.setStatistics(false);
+        sets.setIslandsActive(false);
+
+        // Mock an advancement with awarded criteria
+        Advancement advancement = mock(Advancement.class);
+        NamespacedKey advKey = NamespacedKey.minecraft("story_mine_stone");
+        when(advancement.getKey()).thenReturn(advKey);
+
+        AdvancementProgress progress = mock(AdvancementProgress.class);
+        Set<String> criteria = new HashSet<>(Set.of("mine_stone"));
+        when(progress.getAwardedCriteria()).thenReturn(criteria);
+        when(player.getAdvancementProgress(advancement)).thenReturn(progress);
+
+        try (MockedStatic<Bukkit> mockedBukkit = mockStatic(Bukkit.class, Mockito.RETURNS_MOCKS)) {
+            // Return a fresh iterator each time so both storeInventory and getInventory can iterate
+            mockedBukkit.when(Bukkit::advancementIterator).thenAnswer(inv -> List.of(advancement).iterator());
+
+            // Store inventory (saves advancement data and clears player including XP reset)
+            s.storeInventory(player, world);
+
+            // Load inventory — experience set, advancements granted, XP restored
+            s.getInventory(player, world);
+        }
+
+        // setTotalExperience should be called exactly 3 times:
+        // 1. clearPlayer during storeInventory (XP reset to 0)
+        // 2. experience loading during getInventory (XP set to stored value 0)
+        // 3. XP restoration inside setAdvancements after granting advancement criteria
+        verify(player, times(3)).setTotalExperience(0);
+    }
+
     /**
      * Test method for {@link com.wasteofplastic.invswitcher.Store#removeFromCache(org.bukkit.entity.Player)}.
      */