Implement IEquatable<T> (#40)

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.0",
+    "version": "9.0.0",
     "allowPrerelease": false,
     "rollForward": "latestFeature"
   }

src/Directory.Build.props

@@ -5,7 +5,7 @@
     <ContinuousIntegrationBuild Condition="'$(CI)' == 'true'">true</ContinuousIntegrationBuild>
     <LangVersion>latest</LangVersion>
     <Nullable>enable</Nullable>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Label="ProductInfo">

src/Nethermind.Int256/Int256.cs

@@ -7,7 +7,7 @@
 
 namespace Nethermind.Int256
 {
-    public readonly struct Int256 : IComparable, IComparable<Int256>, IInteger<Int256>, IConvertible
+    public readonly struct Int256 : IEquatable<Int256>, IComparable, IComparable<Int256>, IInteger<Int256>, IConvertible
     {
         public static readonly Int256 Zero = (Int256)0UL;
         public static readonly Int256 One = (Int256)1UL;
@@ -530,8 +530,11 @@ public override string ToString()
             return ToString(null);
         }
 
+        [OverloadResolutionPriority(1)]
         private bool Equals(in Int256 other) => _value.Equals(other._value);
 
+        public bool Equals(Int256 other) => _value.Equals(other._value);
+
         public override bool Equals(object? obj) => obj is Int256 other && Equals(other);
 
         public override int GetHashCode() => _value.GetHashCode();

src/Nethermind.Int256/UInt256.cs

@@ -13,7 +13,7 @@
 namespace Nethermind.Int256
 {
     [StructLayout(LayoutKind.Explicit)]
-    public readonly struct UInt256 : IComparable, IComparable<UInt256>, IInteger<UInt256>, IConvertible
+    public readonly struct UInt256 : IEquatable<UInt256>, IComparable, IComparable<UInt256>, IInteger<UInt256>, IConvertible
     {
         public static readonly UInt256 Zero = 0ul;
         public static readonly UInt256 One = 1ul;
@@ -1803,13 +1803,6 @@ public string ToString(string format)
 
         public bool IsUint64 => (u1 | u2 | u3) == 0;
 
-        public bool Equals(UInt256 other)
-        {
-            var v1 = Unsafe.As<ulong, Vector256<ulong>>(ref Unsafe.AsRef(in u0));
-            var v2 = Unsafe.As<UInt256, Vector256<ulong>>(ref Unsafe.AsRef(in other));
-            return v1 == v2;
-        }
-
         public bool Equals(int other)
         {
             return other >= 0 && Equals((uint)other);
@@ -1843,8 +1836,16 @@ public bool Equals(ulong other)
             }
         }
 
+        [OverloadResolutionPriority(1)]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private bool Equals(in UInt256 other)
+        public bool Equals(in UInt256 other)
+        {
+            var v1 = Unsafe.As<ulong, Vector256<ulong>>(ref Unsafe.AsRef(in u0));
+            var v2 = Unsafe.As<UInt256, Vector256<ulong>>(ref Unsafe.AsRef(in other));
+            return v1 == v2;
+        }
+
+        public bool Equals(UInt256 other)
         {
             var v1 = Unsafe.As<ulong, Vector256<ulong>>(ref Unsafe.AsRef(in u0));
             var v2 = Unsafe.As<UInt256, Vector256<ulong>>(ref Unsafe.AsRef(in other));