feat: Implemented Inventory::can_move

- Changed Inventory::can_fit signature
- Added can_move_item test

src/inventory/mod.rs

@@ -15,7 +15,7 @@ impl Inventory {
     pub fn can_fit(
         &self,
         item_query: Query<&item::Item>,
-        contained_items: &Children,
+        contained_items: &[Entity],
         queried_size: UVec2,
         queried_position: UVec2,
     ) -> bool {
@@ -36,4 +36,21 @@ impl Inventory {
         }
         true
     }
+
+    pub fn can_move(
+        &self,
+        item_query: Query<&item::Item>,
+        contained_items: &[Entity],
+        queried_item: Entity,
+        queried_position: UVec2,
+    ) -> bool {
+        let Ok(item::Item {size, ..}) = item_query.get(queried_item) else {
+            error!("Could not query inventory child ({queried_item}), probably not item?");
+            return false;
+        };
+        let children = contained_items.iter()
+            .filter_map(|e| if e.ne(&&queried_item) { Some(*e) } else { None })
+            .collect::<Vec<Entity>>();
+        self.can_fit(item_query, children.as_slice(), *size, queried_position)
+    }
 }

src/tests.rs

@@ -115,6 +115,9 @@ mod inventory {
     #[derive(Resource)]
     struct Items(Vec<Item>, usize);
 
+    #[derive(Component)]
+    struct MovableItem(UVec2);
+
     fn insert_item(
         mut commands: Commands,
         mut items: ResMut<Items>,
@@ -153,6 +156,16 @@ mod inventory {
         items.1 += 1;
     }
 
+    fn try_to_move(
+        item_query: Query<&Item>,
+        inventory_query: Query<(&Inventory, &Children)>,
+        movable_item: Query<(Entity, &MovableItem)>,
+    ) {
+        let (inventory, children) = inventory_query.single().unwrap();
+        let (movable_item, MovableItem(query_pos)) = movable_item.single().unwrap();
+        assert!(inventory.can_move(item_query, children, movable_item, *query_pos));
+    }
+
     #[test]
     fn everything_fits() {
         let mut world = World::new();
@@ -186,4 +199,18 @@ mod inventory {
             world.run_system(system).expect("Error on running system");
         }
     }
+
+    #[test]
+    fn can_move_item() {
+        let mut world = World::new();
+
+        let system = world.register_system(try_to_move);
+
+        world.spawn(inventory())
+            .with_child((item_a(), MovableItem(UVec2::new(3, 2))))
+            .with_child(item_b())
+            .with_child(item_c());
+
+        world.run_system(system).expect("Error on running system");
+    }
 }