Rework of FFI, adding a value identifier, so we can keep knowledge of data even when data moves.

src/static_data/libraries/item_library.rs

@@ -4,12 +4,14 @@ use indexmap::IndexMap;
 
 use crate::static_data::DataLibrary;
 use crate::static_data::Item;
-use crate::StringKey;
+use crate::{StringKey, ValueIdentifiable, ValueIdentifier};
 
 /// A library to store all items.
 #[derive(Debug)]
 #[cfg_attr(feature = "wasm", derive(unique_type_id_derive::UniqueTypeId))]
 pub struct ItemLibrary {
+    /// A unique identifier so we know what value this is.
+    identifier: ValueIdentifier,
     /// The underlying data structure.
     map: IndexMap<StringKey, Arc<Item>>,
 }
@@ -18,6 +20,7 @@ impl ItemLibrary {
     /// Instantiates a new Item Library.
     pub fn new(capacity: usize) -> ItemLibrary {
         ItemLibrary {
+            identifier: Default::default(),
             map: IndexMap::with_capacity(capacity),
         }
     }
@@ -33,9 +36,16 @@ impl DataLibrary<'_, Item> for ItemLibrary {
     }
 }
 
+impl ValueIdentifiable for ItemLibrary {
+    fn value_identifier(&self) -> ValueIdentifier {
+        self.identifier
+    }
+}
+
 #[cfg(test)]
 pub mod tests {
     use hashbrown::HashSet;
+    use std::sync::Arc;
 
     use crate::static_data::libraries::data_library::DataLibrary;
     use crate::static_data::libraries::item_library::ItemLibrary;
@@ -57,7 +67,7 @@ pub mod tests {
         let m = build_item();
         // Borrow as mut so we can insert
         let w = &mut lib;
-        w.add(&"foo".into(), m);
+        w.add(&"foo".into(), Arc::new(m));
         // Drops borrow as mut
 
         lib