test(core): add SUPER-CHIP extended opcode tests

tests/Chip8.Tests/SuperChipTests.cs

@@ -0,0 +1,143 @@
+using Chip8.Core;
+using Xunit;
+
+namespace Chip8.Tests;
+
+public class SuperChipTests
+{
+    [Fact]
+    public void hiresToggleSwitchesResolution()
+    {
+        var machine = TestHarness.withOpcode(0x00FF, Platform.SuperChip);
+        Assert.False(machine.hires);
+        machine.step();
+        Assert.True(machine.hires);
+        Assert.Equal(Video.hiWidth, machine.video.width);
+        Assert.Equal(Video.hiHeight, machine.video.height);
+    }
+
+    [Fact]
+    public void loresToggleReturnsToSmallResolution()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0x00FF, 0x00FE);
+        machine.step();
+        machine.step();
+        Assert.False(machine.hires);
+        Assert.Equal(Video.loWidth, machine.video.width);
+    }
+
+    [Fact]
+    public void exitHaltsInterpreter()
+    {
+        var machine = TestHarness.withOpcode(0x00FD, Platform.SuperChip);
+        machine.step();
+        Assert.True(machine.exited);
+        Assert.Equal(0x200, machine.pc);
+    }
+
+    [Fact]
+    public void bigSpriteDrawsSixteenBySixteenBlock()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0x00FF, 0xD010);
+        machine.i = 0x300;
+        for (int offset = 0; offset < 32; offset++)
+        {
+            machine.memory[0x300 + offset] = 0xFF;
+        }
+        machine.v[0] = 0;
+        machine.v[1] = 0;
+
+        machine.step();
+        machine.step();
+
+        Assert.Equal(256, AsciiScreen.litPixelCount(machine.video));
+        Assert.Equal(0, machine.v[0xF]);
+    }
+
+    [Fact]
+    public void bigSpriteReportsCollisionOnOverlap()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0xD010, 0xD010);
+        machine.i = 0x300;
+        for (int offset = 0; offset < 32; offset++)
+        {
+            machine.memory[0x300 + offset] = 0xFF;
+        }
+
+        machine.step();
+        Assert.Equal(0, machine.v[0xF]);
+        machine.step();
+        Assert.Equal(1, machine.v[0xF]);
+        Assert.Equal(0, AsciiScreen.litPixelCount(machine.video));
+    }
+
+    [Fact]
+    public void rplFlagsPersistAcrossStoreAndLoad()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0xF375, 0xF385);
+        machine.v[0] = 0x11;
+        machine.v[1] = 0x22;
+        machine.v[2] = 0x33;
+        machine.v[3] = 0x44;
+
+        machine.step();
+
+        machine.v[0] = 0;
+        machine.v[1] = 0;
+        machine.v[2] = 0;
+        machine.v[3] = 0;
+
+        machine.step();
+
+        Assert.Equal(0x11, machine.v[0]);
+        Assert.Equal(0x22, machine.v[1]);
+        Assert.Equal(0x33, machine.v[2]);
+        Assert.Equal(0x44, machine.v[3]);
+    }
+
+    [Fact]
+    public void bigFontPointsAtTenByteGlyph()
+    {
+        var machine = TestHarness.withOpcode(0xF030, Platform.SuperChip);
+        machine.v[0] = 0x3;
+        machine.step();
+        Assert.Equal(0xA0 + 0x3 * FontSet.bigGlyphBytes, machine.i);
+        Assert.Equal(FontSet.bigGlyphs[0x3 * FontSet.bigGlyphBytes], machine.memory[machine.i]);
+    }
+
+    [Fact]
+    public void scrollDownOpcodeMovesContent()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0x00C4);
+        machine.memory[0x300] = 0x80;
+        machine.video.drawSprite(machine.memory, 0x300, 5, 2, 1, 1, false);
+        Assert.True(machine.video.pixel(0, 5, 2));
+
+        machine.step();
+
+        Assert.False(machine.video.pixel(0, 5, 2));
+        Assert.True(machine.video.pixel(0, 5, 6));
+    }
+
+    [Fact]
+    public void scrollRightOpcodeMovesContentFourPixels()
+    {
+        var machine = TestHarness.withProgram(Platform.SuperChip, 0x00FB);
+        machine.memory[0x300] = 0x80;
+        machine.video.drawSprite(machine.memory, 0x300, 5, 2, 1, 1, false);
+
+        machine.step();
+
+        Assert.False(machine.video.pixel(0, 5, 2));
+        Assert.True(machine.video.pixel(0, 9, 2));
+    }
+
+    [Fact]
+    public void scrollingRomRendersMenuUnderSuperChip()
+    {
+        var machine = TestHarness.runRomExtended("8-scrolling.ch8", 1000, Platform.SuperChip);
+        Assert.False(machine.exited);
+        Assert.False(machine.hires);
+        Assert.Equal(254, AsciiScreen.litPixelCount(machine.video));
+    }
+}