More work on switching battle data to interior mutability, instead of exterior mutability.

src/static_data/moves/move_data.rs

@@ -45,7 +45,7 @@ pub struct MoveData {
     base_usages: u8,
     target: MoveTarget,
     priority: i8,
-    secondary_effect: SecondaryEffect,
+    secondary_effect: Option<SecondaryEffect>,
     flags: HashSet<StringKey>,
 }
 
@@ -59,7 +59,7 @@ impl MoveData {
         base_usages: u8,
         target: MoveTarget,
         priority: i8,
-        secondary_effect: SecondaryEffect,
+        secondary_effect: Option<SecondaryEffect>,
         flags: HashSet<StringKey>,
     ) -> MoveData {
         MoveData {
@@ -102,14 +102,10 @@ impl MoveData {
         self.priority
     }
 
-    pub fn secondary_effect(&self) -> &SecondaryEffect {
+    pub fn secondary_effect(&self) -> &Option<SecondaryEffect> {
         &self.secondary_effect
     }
 
-    pub fn has_secondary_effect(&self) -> bool {
-        self.secondary_effect.effect_name() != &StringKey::empty()
-    }
-
     pub fn has_flag(&self, key: &StringKey) -> bool {
         self.flags.contains(key)
     }