feat(world-gen): add CaveCarver skeleton (no-op Carve)

VoxelEngine.Tests/WorldGen/CaveCarverTests.cs

@@ -0,0 +1,38 @@
+using OpenTK.Mathematics;
+using VoxelEngine.Core;
+using VoxelEngine.World.Blocks;
+using VoxelEngine.World.Chunk;
+using VoxelEngine.World.WorldGen;
+using Xunit;
+
+namespace VoxelEngine.Tests.WorldGen;
+
+public class CaveCarverTests
+{
+    private static readonly BlockRegistry Blocks = new();
+    private static readonly Configuration Cfg = new();
+
+    private static Chunk MakeStoneChunk()
+    {
+        Chunk c = new();
+        for (int x = 0; x < Chunk.Size; x++)
+        for (int y = 0; y < Chunk.Size; y++)
+        for (int z = 0; z < Chunk.Size; z++)
+            c[x, y, z] = Blocks.Stone.Id;
+        return c;
+    }
+
+    [Fact]
+    public void Carve_IsNoOpOnAirChunk()
+    {
+        var carver = new CaveCarver(seed: 42, Blocks, Cfg);
+        Chunk c = new(); // all-air by default
+
+        carver.Carve(c, new Vector3i(0, 4, 0));
+
+        for (int x = 0; x < Chunk.Size; x++)
+        for (int y = 0; y < Chunk.Size; y++)
+        for (int z = 0; z < Chunk.Size; z++)
+            Assert.Equal(Blocks.Air.Id, c[x, y, z]);
+    }
+}