Add strong name signing (#2575)

Directory.Build.props

@@ -0,0 +1,7 @@
+<Project>
+  <PropertyGroup Label="Strong name signing">
+    <SignAssembly>true</SignAssembly>
+    <AssemblyOriginatorKeyFile>$(MSBuildThisFileDirectory)\key.snk</AssemblyOriginatorKeyFile>
+    <StrongNameSuffix>, PublicKey=0024000004800000940000000602000000240000525341310004000001000100f1e6b635f0c0b44c03d712e4f2cf789ddb54d7f74a9b34e2ece3aafb6afbfd46ec2b033f4104ef88f6afec226c5c647f453852ba3847fd9e37727c7dcb54e24731a288a107457a2c3e8b26ab04c25b206797be48cfe7a2b2c427422d0b0dd18c82111f21798f997e5d33ecc25c677744709c3785e0e650d6e0456a034a31acc4</StrongNameSuffix>
+  </PropertyGroup>
+</Project>

Octokit.Tests.Integration/Octokit.Tests.Integration.csproj

@@ -5,6 +5,7 @@
     <AssemblyTitle>Octokit.Tests.Integration</AssemblyTitle>
     <Authors>GitHub</Authors>
     <TargetFrameworks>net6.0;netcoreapp3.1;net462</TargetFrameworks>
+    <SignAssembly>false</SignAssembly>
     <NoWarn>$(NoWarn);CS4014;CS1998</NoWarn>
     <AssemblyName>Octokit.Tests.Integration</AssemblyName>
     <PackageId>Octokit.Tests.Integration</PackageId>

Octokit/Octokit.csproj

@@ -32,4 +32,9 @@
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All" />
   </ItemGroup>
 
+  <ItemGroup Label="InternalsVisibleTo attributes">
+    <AssemblyAttribute Include="System.Runtime.CompilerServices.InternalsVisibleTo">
+      <_Parameter1>Octokit.Tests$(StrongNameSuffix)</_Parameter1>
+    </AssemblyAttribute>
+  </ItemGroup>
 </Project>

Octokit/Properties/AssemblyInfo.cs

@@ -1,3 +0,0 @@
-using System.Runtime.CompilerServices;
-
-[assembly: InternalsVisibleTo("Octokit.Tests")]

build/Build.csproj

@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
+    <SignAssembly>false</SignAssembly>
     <TargetFramework>netcoreapp3.1</TargetFramework>
     <RunWorkingDirectory>$(MSBuildProjectDirectory)/..</RunWorkingDirectory>
   </PropertyGroup>