chore: replace select unreachable! macros with todo! and unreachable!

src/bus.rs

@@ -120,7 +120,7 @@ impl Bus {
                 // Sprite Attribute Table
                 unimplemented!("Unable to read {:#06X} in the Sprite Attribute Table", addr);
             }
-            0xFEA0..=0xFEFF => unimplemented!("{:#06X} is not allowed to be used", addr),
+            0xFEA0..=0xFEFF => unreachable!("{:#06X} is not allowed to be used", addr),
             0xFF00..=0xFF7F => {
                 // IO Registers
                 match addr {
@@ -204,12 +204,9 @@ impl Bus {
             }
             0xFE00..=0xFE9F => {
                 // Sprite Attribute Table
-                unimplemented!(
-                    "Unable to write to {:#06X} in the Sprite Attribute Table",
-                    addr
-                );
+                unimplemented!("Unable to write to {:#06X} in Sprite Attribute Table", addr);
             }
-            0xFEA0..=0xFEFF => unimplemented!("{:#06X} is not allowed to be used", addr),
+            0xFEA0..=0xFEFF => unreachable!("{:#06X} is not allowed to be used", addr),
             0xFF00..=0xFF7F => {
                 // IO Registers
                 match addr {

src/cartridge.rs

@@ -187,7 +187,7 @@ impl MemoryBankController for MBC1 {
                     Value(0xFF)
                 }
             }
-            _ => unimplemented!(),
+            _ => unreachable!("A read from {:#06X} should not be handled by MBC1", addr),
         }
     }
 
@@ -209,7 +209,7 @@ impl MemoryBankController for MBC1 {
                     self.ram[ram_addr as usize] = byte;
                 }
             }
-            _ => unreachable!("{:#06X} should not be handled by MBC1", addr),
+            _ => unreachable!("A write to {:#06X} should not be handled by MBC1", addr),
         }
     }
 }

src/instruction.rs

@@ -541,7 +541,7 @@ impl Instruction {
                 cpu.set_register(Register::A, rot_a);
                 Cycles::new(4)
             }
-            Instruction::DAA => unimplemented!(),
+            Instruction::DAA => todo!("Implement DAA Instruction"),
             Instruction::CPL => {
                 // Compliment A register (inverse)
                 let mut flags: Flags = *cpu.flags();
@@ -576,7 +576,7 @@ impl Instruction {
                 cpu.set_flags(flags);
                 Cycles::new(4)
             }
-            Instruction::HALT => unimplemented!(),
+            Instruction::HALT => todo!("Implement HALT instruction"),
             Instruction::ADC(target) => match target {
                 MATHTarget::Register(reg) => {
                     // ADC A, r[z] | Add register r[z] plus the Carry flag to A