enforce IDE0005 on build and remove unnecessary usings (#306)

Set EnforceCodeStyleInBuild and GenerateDocumentationFile in Directory.Build.props,
suppress CS1591 for test and integration projects, and clear the 15 usings this
  surfaced.

Author: FreeAndNil

.editorconfig

@@ -206,6 +206,9 @@ dotnet_diagnostic.KR1037.severity = none
 dotnet_diagnostic.NUnit2045.severity = none
 # IDE0079: Remove unnecessary suppressions
 dotnet_diagnostic.IDE0079.severity = none
+# IDE0005: Remove unnecessary usings. Shown in the IDE only: enforcing it on build would also need
+# EnforceCodeStyleInBuild and GenerateDocumentationFile, which the test projects do not set.
+dotnet_diagnostic.IDE0005.severity = warning
 
 [*.xml]
 tab_width = 2

src/Directory.Build.props

@@ -9,10 +9,18 @@
     <AnalysisLevel>8</AnalysisLevel>
     <RunAnalyzersDuringBuild>true</RunAnalyzersDuringBuild>
     <RunAnalyzersDuringLiveAnalysis>true</RunAnalyzersDuringLiveAnalysis>
+    <!-- Reports code style rules such as IDE0005 (unnecessary usings) on build, not only in the
+         IDE. IDE0005 needs the documentation file, so that is switched on everywhere too. -->
+    <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <_SkipUpgradeNetAnalyzersNuGetWarning>true</_SkipUpgradeNetAnalyzersNuGetWarning>
     <AccelerateBuildsInVisualStudio>true</AccelerateBuildsInVisualStudio>
     <SatelliteResourceLanguages>en;en-US</SatelliteResourceLanguages>
   </PropertyGroup>
+  <PropertyGroup Condition="$(MSBuildProjectName.Contains('Tests')) or $(MSBuildProjectDirectory.Contains('integration-testing'))">
+    <!-- Only the shipping libraries have to document their public surface. -->
+    <NoWarn>$(NoWarn);CS1591</NoWarn>
+  </PropertyGroup>
   <PropertyGroup Label="Package Versions">
     <VersionPrefix>3.4.0</VersionPrefix>
     <Log4NetPackageVersion>3.3.2</Log4NetPackageVersion>

src/integration-testing/log4net-611-lib/DerivedAppender.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Diagnostics;
 using log4net.Appender;
 using log4net.Core;
 

src/log4net.Ext.Mail.Tests/Appender/FakeSmtpTransport.cs

@@ -23,7 +23,6 @@
 using System.Net;
 using System.Text;
 
-using log4net.Ext.Mail.Appender;
 using log4net.Ext.Mail.Appender.Internal;
 
 using MailKit.Security;

src/log4net.Ext.Mail.Tests/Appender/SmtpAppenderTest.cs

@@ -24,7 +24,6 @@
 using System.Text;
 using log4net.Core;
 using log4net.Ext.Mail.Appender;
-using log4net.Ext.Mail.Appender.Internal;
 using log4net.Layout;
 using MailKit.Security;
 using MimeKit;

src/log4net.Ext.Mail.Tests/log4net.Ext.Mail.Tests.csproj

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <IsTestProject>true</IsTestProject>
     <TargetFrameworks>net10.0</TargetFrameworks>
-    <NoWarn>NETSDK1138;CS1701</NoWarn>
+    <NoWarn>$(NoWarn);NETSDK1138;CS1701</NoWarn>
     <OutputType>Library</OutputType>
     <OutputPath>bin\$(Configuration)</OutputPath>
     <Configurations>Debug;Release</Configurations>
@@ -11,7 +11,7 @@
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <DefineConstants>TRACE;DEBUG;$(DefineConstants)</DefineConstants>
     <!-- suppress analyzer mismatch warning -->
-    <NoWarn>CS8032</NoWarn>
+    <NoWarn>$(NoWarn);CS8032</NoWarn>
     <VSTestLogger>quackers</VSTestLogger>
   </PropertyGroup>
   <ItemGroup>

src/log4net.Tests/Appender/AppenderSkeletonTest.cs

@@ -49,7 +49,7 @@ public void AddFilter_FirstFilter_SetsFilterHead()
   }
 
   /// <summary>
-  /// Verifies that a second <see cref="AppenderSkeleton.AddFilter"/> call appends the filter via <see cref="Filter.IFilter.Next"/>.
+  /// Verifies that a second <see cref="AppenderSkeleton.AddFilter"/> call appends the filter via <c>IFilter.Next</c>.
   /// </summary>
   [Test]
   public void AddFilter_SecondFilter_LinksToChain()

src/log4net.Tests/Core/LoggingEventTest.cs

@@ -19,9 +19,11 @@
 
 using System;
 using System.Globalization;
-using System.IO;
 using System.Reflection;
+#if NET462_OR_GREATER
+using System.IO;
 using System.Runtime.Serialization.Formatters.Binary;
+#endif
 using log4net.Core;
 using log4net.Util;
 using NUnit.Framework;
@@ -119,7 +121,7 @@ public void DeserializeV2()
 #endif // NET462_OR_GREATER
 
   /// <summary>
-  /// Tests <see cref="LoggingEvent.ReviseThreadName"/>
+  /// Tests <c>LoggingEvent.ReviseThreadName</c>, which is not publicly visible.
   /// </summary>
   [Test]
   public void ReviseThreadNameTest()

src/log4net.Tests/Core/ShutdownTest.cs

@@ -29,7 +29,8 @@
 namespace log4net.Tests.Core;
 
 /// <summary>
-/// </remarks>
+/// Tests shutting log4net down.
+/// </summary>
 [TestFixture]
 public class ShutdownTest
 {

src/log4net.Tests/Hierarchy/XmlHierarchyConfiguratorTest.cs

@@ -23,7 +23,6 @@
 using NUnit.Framework;
 
 using log4net.Repository.Hierarchy;
-using HierarchyClass = log4net.Repository.Hierarchy.Hierarchy;
 
 namespace log4net.Tests.Hierarchy;