Modernize frameworks (#100)

Migrate tests and CI to dotnet 6

Author: camrein

appveyor.yml

@@ -1,4 +1,4 @@
-image: Visual Studio 2019
+image: Visual Studio 2022
 version: '{build}'
 configuration: Release
 
@@ -12,7 +12,7 @@ before_test:
   - dotnet tool install --global coverlet.console --version 1.7.0
 
 test_script:
-  - ps: coverlet src\ParallelHelper.Test\bin\Release\netcoreapp3.1\ParallelHelper.Test.dll --target "dotnet" --targetargs 'test src\ParallelHelper.Test -c Release -logger:""C:\Program Files\AppVeyor\BuildAgent\dotnetcore\Appveyor.MSBuildLogger.dll"" --no-build' --format opencover --output coverage.xml
+  - ps: coverlet src\ParallelHelper.Test\bin\Release\net6.0\ParallelHelper.Test.dll --target "dotnet" --targetargs 'test src\ParallelHelper.Test -c Release -logger:""C:\Program Files\AppVeyor\BuildAgent\dotnetcore\Appveyor.MSBuildLogger.dll"" --no-build' --format opencover --output coverage.xml
 
 after_test:
   - ps: |

src/ParallelHelper.Test/DiagnosticResultLocation.cs

@@ -35,14 +35,14 @@ public override string ToString() {
       return $"{Path}: {Line},{Column}";
     }
 
-    public static bool operator==(DiagnosticResultLocation left, DiagnosticResultLocation right) {
+    public static bool operator==(DiagnosticResultLocation? left, DiagnosticResultLocation? right) {
       if(left == null) {
         return right == null;
       }
       return left.Equals(right);
     }
 
-    public static bool operator!=(DiagnosticResultLocation left, DiagnosticResultLocation right) {
+    public static bool operator!=(DiagnosticResultLocation? left, DiagnosticResultLocation? right) {
       return !(left == right);
     }
   }

src/ParallelHelper.Test/ParallelHelper.Test.csproj

@@ -1,10 +1,9 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
     <LangVersion>8.0</LangVersion>
     <Nullable>enable</Nullable>
-    <NullableContextOptions>enable</NullableContextOptions> <!-- pre vs 2019.2 -->
   </PropertyGroup>
 
   <ItemGroup>

src/ParallelHelper.Test/TestAnalyzerConfigOptionsProvider.cs

@@ -1,6 +1,7 @@
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
 using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
 
 namespace ParallelHelper.Test {
   /// <summary>
@@ -29,7 +30,7 @@ public TestAnalyzerConfigOptions(ImmutableDictionary<string, string> options) {
         _options = options.WithComparers(KeyComparer);
       }
 
-      public override bool TryGetValue(string key, out string value) {
+      public override bool TryGetValue(string key, [NotNullWhen(true)] out string? value) {
         return _options.TryGetValue(key, out value);
       }
     }

src/ParallelHelper/ParallelHelper.csproj

@@ -6,7 +6,6 @@
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <LangVersion>8.0</LangVersion>
     <Nullable>enable</Nullable>
-    <NullableContextOptions>enable</NullableContextOptions> <!-- pre vs 2019.2 -->
   </PropertyGroup>
 
   <PropertyGroup>