fix(item): prevent stacking items with different components (#2624)

pumpkin-data/src/item_stack/mod.rs

@@ -579,6 +579,11 @@ impl ItemStack {
         if self.item != other.item {
             return false;
         }
+
+        if self.patch.len() != other.patch.len() {
+            return false;
+        }
+
         for (id, data) in &self.patch {
             let mut not_found = true;
             'out: for (other_id, other_data) in &other.patch {
@@ -745,6 +750,20 @@ mod tests {
         ItemStack::new(1, &Item::IRON_SWORD)
     }
 
+    #[test]
+    fn items_with_different_components_are_not_equal_in_either_direction() {
+        let plain = ItemStack::new(1, &Item::COAL);
+
+        let mut customized = ItemStack::new(1, &Item::COAL);
+        customized
+            .patch
+            .push((DataComponent::Unbreakable, Some(UnbreakableImpl.to_dyn())));
+
+        assert!(!plain.are_items_and_components_equal(&customized));
+        assert!(!customized.are_items_and_components_equal(&plain));
+        assert!(customized.are_items_and_components_equal(&customized.clone()));
+    }
+
     #[test]
     fn custom_data_sets_and_reads_typed_values() {
         let mut stack = ItemStack::new(1, &Item::WOODEN_AXE);