cpu.rs: Separate lastkey from flags

src/cpu/behavior.rs

@@ -528,9 +528,9 @@ impl CPU {
     /// |`Fx0A`| Wait for key, then vX = K
     #[inline(always)]
     pub(super) fn wait_for_key(&mut self, x: Reg) {
-        if let Some(key) = self.flags.lastkey {
+        if let Some(key) = self.lastkey {
             self.v[x] = key as u8;
-            self.flags.lastkey = None;
+            self.lastkey = None;
         } else {
             self.pc = self.pc.wrapping_sub(2);
             self.flags.keypause = true;

src/cpu/flags.rs

@@ -19,8 +19,6 @@ pub struct Flags {
     pub draw_wait: bool,
     /// Set when the emulator is in high-res mode
     pub draw_mode: bool,
-    /// Set to the last key that's been *released* after a keypause
-    pub lastkey: Option<usize>,
     /// Represents the current emulator [Mode]
     pub mode: Mode,
     /// Represents the set of emulator [Quirks] to enable, independent of the [Mode]

src/cpu/tests.rs

@@ -861,7 +861,7 @@ mod io {
                     assert!(cpu.release(key).expect("Key should be released"));
                     assert!(!cpu.release(key).expect("Key shouldn't be released again"));
                     assert!(!cpu.flags.keypause);
-                    assert_eq!(Some(key), cpu.flags.lastkey);
+                    assert_eq!(Some(key), cpu.lastkey);
                     cpu.wait_for_key(x);
                     assert_eq!(key as u8, cpu.v[x]);
                 }