Add SkipLocalsInit attribute (#1303)

Jint/AssemblyInfoExtras.cs

@@ -1,5 +1,5 @@
-using System.Runtime.CompilerServices;
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("Jint.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("Jint.Tests.Test262, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("Jint.Benchmark, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
 
-[assembly: InternalsVisibleTo("Jint.Tests, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
-[assembly: InternalsVisibleTo("Jint.Tests.Test262, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
-[assembly: InternalsVisibleTo("Jint.Benchmark, PublicKey=0024000004800000940000000602000000240000525341310004000001000100bf2553c9f214cb21f1f64ed62cadad8fe4f2fa11322a5dfa1d650743145c6085aba05b145b29867af656e0bb9bfd32f5d0deb1668263a38233e7e8e5bad1a3c6edd3f2ec6c512668b4aa797283101444628650949641b4f7cb16707efba542bb754afe87ce956f3a5d43f450d14364eb9571cbf213d1061852fb9dd47a6c05c4")]
+[module: System.Runtime.CompilerServices.SkipLocalsInit]

Jint/IsExternalInit.cs

@@ -0,0 +1,21 @@
+#if !NET5_0_OR_GREATER
+
+// Source: https://github.com/dotnet/runtime/blob/v6.0.5/src/libraries/Common/src/System/Runtime/CompilerServices/IsExternalInit.cs
+
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.ComponentModel;
+
+namespace System.Runtime.CompilerServices;
+
+/// <summary>
+/// Reserved to be used by the compiler for tracking metadata.
+/// This class should not be used by developers in source code.
+/// </summary>
+[EditorBrowsable(EditorBrowsableState.Never)]
+internal static class IsExternalInit
+{
+}
+
+#endif

Jint/Jint.csproj

@@ -8,11 +8,11 @@
     <IsPackable>true</IsPackable>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
 
   <ItemGroup>
     <PackageReference Include="Esprima" Version="3.0.0-beta-7" />
-    <PackageReference Include="IsExternalInit" Version="1.0.2" PrivateAssets="all" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="all" />
     <PackageReference Include="Nullable" Version="1.3.0" PrivateAssets="all" />
   </ItemGroup>

Jint/SkipLocalsInitAttribute.cs

@@ -0,0 +1,15 @@
+namespace System.Runtime.CompilerServices;
+
+[AttributeUsage(
+    AttributeTargets.Module
+    | AttributeTargets.Class
+    | AttributeTargets.Struct
+    | AttributeTargets.Interface
+    | AttributeTargets.Constructor
+    | AttributeTargets.Method
+    | AttributeTargets.Property
+    | AttributeTargets.Event, Inherited = false)]
+internal sealed class SkipLocalsInitAttribute : Attribute
+{
+    public SkipLocalsInitAttribute() { }
+}