gb-player/gb/cpu_test.go
2025-08-21 19:53:41 +02:00

123 lines
2.4 KiB
Go

package gb
import (
"testing"
"github.com/stretchr/testify/assert"
)
func createCPU(data []byte) *CPU {
cart := Cartridge{Filename: "test"}
cart.Data = data
cpu := NewCPU(NewBus(&cart))
cpu.Regs.PC = 0
return cpu
}
func TestSetFlag(t *testing.T) {
cartridge, _ := InsertCartridge("../roms/dmg-acid2.gb")
bus := NewBus(cartridge)
cpu := NewCPU(bus)
cpu.SetFlag(C)
assert.True(t, cpu.IsFlagSet(C))
}
func TestClearFlag(t *testing.T) {
cartridge, _ := InsertCartridge("../roms/dmg-acid2.gb")
bus := NewBus(cartridge)
cpu := NewCPU(bus)
cpu.SetFlag(C)
assert.True(t, cpu.IsFlagSet(C))
cpu.ClearFlag(C)
assert.False(t, cpu.IsFlagSet(C))
}
func TestToggleFlag(t *testing.T) {
cartridge, _ := InsertCartridge("../roms/dmg-acid2.gb")
bus := NewBus(cartridge)
cpu := NewCPU(bus)
cpu.ToggleFlag(C)
assert.True(t, cpu.IsFlagSet(C))
cpu.ToggleFlag(C)
assert.False(t, cpu.IsFlagSet(C))
}
func TestInstruction00(t *testing.T) {
cpu := createCPU([]byte{0x00, 0x00, 0x00})
cpu.Step()
assert.Equal(t, cpu.Regs.PC, uint16(0x01))
}
func TestInstruction3C(t *testing.T) {
// Should increment A register
cpu := createCPU([]byte{0x3C, 0x00, 0x00})
assert.Equal(t, cpu.Regs.A, byte(0x0))
cpu.Step()
assert.Equal(t, cpu.Regs.A, byte(0x01))
// Should clear Zero Flag
cpu = createCPU([]byte{0x3C, 0x00, 0x00})
cpu.SetFlag(Z)
cpu.Step()
assert.False(t, cpu.IsFlagSet(Z))
// Should set Zero Flag
cpu = createCPU([]byte{0x3C, 0x00, 0x00})
cpu.Regs.A = 0xFF
assert.False(t, cpu.IsFlagSet(Z))
cpu.Step()
assert.True(t, cpu.IsFlagSet(Z))
// Should clear Subtract Flag
cpu = createCPU([]byte{0x3C, 0x00, 0x00})
cpu.SetFlag(N)
cpu.Step()
assert.False(t, cpu.IsFlagSet(N))
// Should set Half Carry Flag if we overflow from bit 3
cpu = createCPU([]byte{0x3C, 0x00, 0x00})
cpu.Regs.A = 0x0F
assert.False(t, cpu.IsFlagSet(H))
cpu.Step()
assert.True(t, cpu.IsFlagSet(H))
// Should clear Half Carry Flag if we don't overflow from bit 3
cpu = createCPU([]byte{0x3C, 0x00, 0x00})
cpu.SetFlag(H)
cpu.Step()
assert.False(t, cpu.IsFlagSet(H))
}
func TestInstructionC3(t *testing.T) {
cpu := createCPU([]byte{0xC3, 0x50, 0x01})
cpu.Step()
assert.Equal(t, cpu.Regs.PC, uint16(0x150))
}
func TestInstructionE9(t *testing.T) {
cpu := createCPU([]byte{0xE9, 0x00, 0x00})
cpu.Regs.H = 0x12
cpu.Regs.L = 0x34
cpu.Step()
assert.Equal(t, cpu.Regs.PC, uint16(0x1234))
}