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

src/static_data/libraries/nature_library.rs

@@ -1,11 +1,13 @@
 use crate::static_data::Nature;
-use crate::StringKey;
+use crate::{StringKey, ValueIdentifiable, ValueIdentifier};
 use hashbrown::HashMap;
 use std::sync::Arc;
 
 /// A library of all natures that can be used, stored by their names.
 #[derive(Debug)]
 pub struct NatureLibrary {
+    /// A unique identifier so we know what value this is.
+    identifier: ValueIdentifier,
     /// The underlying data structure.
     map: HashMap<StringKey, Arc<Nature>>,
 }
@@ -14,13 +16,14 @@ impl NatureLibrary {
     /// Creates a new nature library with a given capacity.
     pub fn new(capacity: usize) -> Self {
         NatureLibrary {
+            identifier: Default::default(),
             map: HashMap::with_capacity(capacity),
         }
     }
 
     /// Adds a new nature with name to the library.
-    pub fn load_nature(&mut self, name: StringKey, nature: Nature) {
-        self.map.insert(name, Arc::new(nature));
+    pub fn load_nature(&mut self, name: StringKey, nature: Arc<Nature>) {
+        self.map.insert(name, nature);
     }
 
     /// Gets a nature by name.
@@ -29,11 +32,11 @@ impl NatureLibrary {
     }
 
     /// Finds a nature name by nature.
-    pub fn get_nature_name(&self, nature: &Arc<Nature>) -> StringKey {
+    pub fn get_nature_name(&self, nature: &Nature) -> StringKey {
         for kv in &self.map {
             // As natures can't be copied, and should always be the same reference as the value
             // in the map, we just compare by reference.
-            if Arc::ptr_eq(kv.1, nature) {
+            if std::ptr::eq(Arc::as_ptr(kv.1), nature) {
                 return kv.0.clone();
             }
         }
@@ -41,6 +44,12 @@ impl NatureLibrary {
     }
 }
 
+impl ValueIdentifiable for NatureLibrary {
+    fn value_identifier(&self) -> ValueIdentifier {
+        self.identifier
+    }
+}
+
 #[cfg(test)]
 pub mod tests {
     use crate::static_data::statistics::Statistic;