Change get_cpu to return mutable reference

Co-authored-by: Ava Silver <ava@avasilver.dev>

src/systems/basic.rs

@@ -91,8 +91,8 @@ pub struct BasicSystem {
 }
 
 impl System for BasicSystem {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> Duration {

src/systems/c64/mod.rs

@@ -313,8 +313,8 @@ pub struct C64System {
 }
 
 impl System for C64System {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> Duration {

src/systems/easy.rs

@@ -93,8 +93,8 @@ pub struct Easy6502System {
 }
 
 impl System for Easy6502System {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> Duration {

src/systems/klaus.rs

@@ -45,8 +45,8 @@ pub struct KlausSystem {
 }
 
 impl System for KlausSystem {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> Duration {

src/systems/mod.rs

@@ -25,7 +25,7 @@ pub trait BuildableSystem<RomRegistry, SystemConfig> {
 /// A representation of an emulated system.
 pub trait System {
   /// Return a mutable reference to the CPU used in this system.
-  fn get_cpu(&self) -> Box<&dyn Cpu>;
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu>;
 
   /// Advance the system by one tick.
   fn tick(&mut self) -> Duration;

src/systems/pet/mod.rs

@@ -210,8 +210,8 @@ pub struct PetSystem {
 }
 
 impl System for PetSystem {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> Duration {

src/systems/vic/mod.rs

@@ -311,8 +311,8 @@ pub struct Vic20System {
 }
 
 impl System for Vic20System {
-  fn get_cpu(&self) -> Box<&dyn Cpu> {
-    Box::new(&self.cpu)
+  fn get_cpu_mut(&mut self) -> Box<&mut dyn Cpu> {
+    Box::new(&mut self.cpu)
   }
 
   fn tick(&mut self) -> instant::Duration {