Add: CopyTo

src/Lua/Internal/AutoResizeArrayCore.cs

@@ -1,87 +0,0 @@
-using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
-
-namespace Lua.Internal;
-
-internal struct AutoResizeArrayCore<T>
-{
-    T[]? array;
-    int size;
-
-    public int Size => size;
-    public int Capacity => array == null ? 0 : array.Length;
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public void Add(T item)
-    {
-        this[size] = item;
-    }
-
-    public ref T this[int index]
-    {
-        get
-        {
-            EnsureCapacity(index);
-            size = Math.Max(size, index + 1);
-
-#if NET6_0_OR_GREATER
-            ref var reference = ref MemoryMarshal.GetArrayDataReference(array!);
-#else
-            ref var reference = ref MemoryMarshal.GetReference(array.AsSpan());
-#endif
-
-            return ref Unsafe.Add(ref reference, index);
-        }
-    }
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public Span<T> AsSpan()
-    {
-        return array.AsSpan(0, size);
-    }
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public T[] GetInternalArray()
-    {
-        return array ?? [];
-    }
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public void Clear()
-    {
-        array.AsSpan().Clear();
-    }
-
-    public void EnsureCapacity(int newCapacity, bool overrideSize = false)
-    {
-        var capacity = 64;
-        while (capacity <= newCapacity)
-        {
-            capacity = MathEx.NewArrayCapacity(capacity);
-        }
-
-        if (array == null)
-        {
-            array = new T[capacity];
-        }
-        else
-        {
-            Array.Resize(ref array, capacity);
-        }
-
-        if (overrideSize)
-        {
-            size = newCapacity;
-        }
-    }
-
-    public void Shrink(int newSize)
-    {
-        if (array != null && array.Length > newSize)
-        {
-            array.AsSpan(newSize).Clear();
-        }
-
-        size = newSize;
-    }
-}

src/Lua/Internal/FastStackCore.cs

@@ -85,4 +85,15 @@ public struct FastStackCore<T>
         array.AsSpan(0, tail).Clear();
         tail = 0;
     }
+
+    public void CopyTo(ref FastStackCore<T> destination)
+    {
+        if (destination.array.Length < array.Length)
+        {
+            Array.Resize(ref destination.array, array.Length);
+        }
+
+        array.AsSpan().CopyTo(destination.array);
+        destination.tail = tail;
+    }
 }

src/Lua/Runtime/LuaStack.cs

@@ -94,6 +94,13 @@ public class LuaStack(int initialSize = 256)
 #endif
     }
 
+    public void CopyTo(LuaStack destination)
+    {
+        destination.EnsureCapacity(top);
+        array.AsSpan().CopyTo(destination.array);
+        destination.top = top;
+    }
+
     static void ThrowEmptyStack()
     {
         throw new InvalidOperationException("Empty stack");