Enable implicit usings in most projects

Author: bradwilson

src/Directory.Build.props

@@ -11,6 +11,7 @@
     <DebugType Condition=" '$(TargetFrameworkIdentifier)' != '.NETFramework' ">embedded</DebugType>
     <DefineConstants>$(DefineConstants);XUNIT_NULLABLE;XUNIT_OVERLOAD_RESOLUTION_PRIORITY;XUNIT_POINTERS</DefineConstants>
     <DefineConstants Condition=" $(MSBuildProjectName.Contains('.aot')) ">$(DefineConstants);XUNIT_AOT</DefineConstants>
+    <ImplicitUsings Condition=" '$(ImplicitUsings)' == '' ">true</ImplicitUsings>
     <IsAotCompatible Condition=" $(MSBuildProjectName.Contains('.aot')) ">true</IsAotCompatible>
     <LangVersion>14.0</LangVersion>
     <MSBuildCopyContentTransitively>false</MSBuildCopyContentTransitively>
@@ -22,6 +23,10 @@
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
   </PropertyGroup>
 
+  <ItemGroup Condition=" '$(ImplicitUsings)' == 'true' ">
+    <Using Include="System.Diagnostics.CodeAnalysis; System.Globalization; Xunit.Internal"/>
+  </ItemGroup>
+
   <ItemGroup>
     <PackageReference Include="Nerdbank.GitVersioning" Version="$(Nerdbank_GitVersioning_Version)">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

src/common.tests/Compilation/AcceptanceTestAssembly.cs

@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Threading.Tasks;
-using Xunit.Internal;
-
 public abstract class AcceptanceTestAssembly :
 	IDisposable
 {

src/common.tests/Extensions/EnumerableExtensions.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 public static class EnumerableExtensions
 {
 #pragma warning disable CS1998 // Async method lacks 'await' operators and will run synchronously

src/common.tests/Extensions/MemoryExtensions.cs

@@ -1,5 +1,3 @@
-using System;
-
 internal static class MemoryExtensions
 {
 	public static Memory<T> Memoryify<T>(this T[]? values) =>

src/common.tests/Extensions/SetExtensions.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 internal static class SetExtensions
 {
 	public static SortedSet<T> ToSortedSet<T>(

src/common.tests/Extensions/SpanExtensions.cs

@@ -1,5 +1,3 @@
-using System;
-
 internal static class SpanExtensions
 {
 	public static Span<T> Spanify<T>(this T[]? values) =>

src/common.tests/TestDoubles/SpyMessageSink.cs

@@ -1,6 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.Threading;
 using Xunit.Sdk;
 
 public class SpyMessageSink : IMessageSink

src/common.tests/TestDoubles/SpyRunnerLogger.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 namespace Xunit.Runner.Common;
 
 public class SpyRunnerLogger : IRunnerLogger

src/common.tests/TestDoubles/SpyRunnerReporter.cs

@@ -1,7 +1,5 @@
 #pragma warning disable xUnit3001 // This class is not created at runtime by the framework
 
-using System.Collections.Generic;
-using System.Threading.Tasks;
 using Xunit.Sdk;
 
 namespace Xunit.Runner.Common;

src/common.tests/TestDoubles/TestData.Messages.cs

@@ -1,5 +1,3 @@
-using System;
-using System.Collections.Generic;
 using Xunit.Runner.Common;
 using Xunit.Sdk;