Fix for MemorySlice.ToArray on default values

CSharpExt.UnitTests/Structs/MemorySliceTests.cs

@@ -0,0 +1,36 @@
+using FluentAssertions;
+using Noggog;
+using Xunit;
+
+namespace CSharpExt.UnitTests.Structs;
+
+public class MemorySliceTests
+{
+    [Fact]
+    public void DefaultToArray()
+    {
+        var sut = default(MemorySlice<byte>);
+        sut.ToArray().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void ReadonlyDefaultToArray()
+    {
+        var sut = default(ReadOnlyMemorySlice<byte>);
+        sut.ToArray().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void DefaultZeroLengthToArray()
+    {
+        var sut = new MemorySlice<byte>(new byte[6], 4, 0);
+        sut.ToArray().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void ReadonlyZeroLengthDefaultToArray()
+    {
+        var sut = new ReadOnlyMemorySlice<byte>(new byte[6], 4, 0);
+        sut.ToArray().Should().BeEmpty();
+    }
+}

Noggog.CSharpExt/Structs/MemorySlice.cs

@@ -82,6 +82,7 @@ public IEnumerator<T> GetEnumerator()
     [Pure]
     public T[] ToArray()
     {
+        if (_arr == null || _length == 0) return Array.Empty<T>();
         var ret = new T[_length];
         Array.Copy(_arr, _startPos, ret, 0, _length);
         return ret;
@@ -206,6 +207,7 @@ public IEnumerator<T> GetEnumerator()
     [Pure]
     public T[] ToArray()
     {
+        if (_arr == null || _length == 0) return Array.Empty<T>();
         var ret = new T[_length];
         Array.Copy(_arr, _startPos, ret, 0, _length);
         return ret;