chore: upgrade dotnet and dependencies to latest LTS versions (#561)

Chris-Wolfgang · web-flow · commit 20c83c7009f7 · 2025-12-27T10:22:27.000-08:00
* Upgraded from .net 6.0 to 8.0 and upgraded nuget packages

* Upgraded code to make it net 8 compatible

Adopt nullable reference types and modernize tests

Updated method signatures to use nullable reference types (`string?`, `params string?[]`, etc.) for improved nullability handling and alignment with C# 8.0 standards. Refactored floating-point parsing tests to use explicit `double` types and introduced `GetDoublePointSymbolsData` for better test coverage.

Improved assertions by replacing outdated patterns (e.g., `Assert.True(false)`) with clearer alternatives like `Assert.Fail`. Enhanced null handling in tests by updating parameters and default values to handle nullable scenarios explicitly.

Modernized syntax with updated collection initializers and nullable annotations. Fixed a typo in a method name and ensured consistent use of nullable annotations across the codebase. Added test cases to cover edge cases and improve validation logic.

Performed general code cleanup, including removing redundant comments, consolidating test data, and improving formatting for readability and maintainability.
diff --git a/src/CommandLineUtils/McMaster.Extensions.CommandLineUtils.csproj b/src/CommandLineUtils/McMaster.Extensions.CommandLineUtils.csproj
@@ -1,7 +1,7 @@
 ﻿<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <IsPackable>true</IsPackable>
     <Description>Command-line parsing API.</Description>
@@ -25,4 +25,8 @@ McMaster.Extensions.CommandLineUtils.ArgumentEscaper
     <None Include="..\..\README.md" Pack="true" PackagePath="\" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Update="Microsoft.CodeAnalysis.PublicApiAnalyzers" Version="3.3.4" />
+  </ItemGroup>
+
 </Project>
diff --git a/src/Hosting.CommandLine/McMaster.Extensions.Hosting.CommandLine.csproj b/src/Hosting.CommandLine/McMaster.Extensions.Hosting.CommandLine.csproj
@@ -1,20 +1,24 @@
-<Project Sdk="Microsoft.NET.Sdk">
+﻿<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <IsPackable>true</IsPackable>
     <Description>Provides command-line parsing API integration with the generic host API (Microsoft.Extensions.Hosting).</Description>
     <PackageTags>commandline;parsing;hosting</PackageTags>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="6.0.0" />
-    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="6.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="9.0.10" />
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="9.0.10" />
   </ItemGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\CommandLineUtils\McMaster.Extensions.CommandLineUtils.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <PackageReference Update="Microsoft.CodeAnalysis.PublicApiAnalyzers" Version="3.3.4" />
+  </ItemGroup>
+
 </Project>
diff --git a/test/CommandLineUtils.Tests/AttributeValidatorTests.cs b/test/CommandLineUtils.Tests/AttributeValidatorTests.cs
@@ -94,7 +94,7 @@ private void OnExecute() { }
         [InlineData("email", 1)]
         [InlineData("email@email@email", 1)]
         [InlineData("email@example.com", 0)]
-        public void ValidatesEmailArgument(string email, int exitCode)
+        public void ValidatesEmailArgument(string? email, int exitCode)
         {
             Assert.Equal(exitCode, CommandLineApplication.Execute<EmailArgumentApp>(new TestConsole(_output), email));
         }
diff --git a/test/CommandLineUtils.Tests/CommandLineApplicationExecutorTests.cs b/test/CommandLineUtils.Tests/CommandLineApplicationExecutorTests.cs
@@ -197,7 +197,7 @@ private class HelpClass
         {
             private void OnExecute()
             {
-                Assert.True(false, "This should not execute");
+                Assert.Fail("This should not execute");
             }
         }
 
diff --git a/test/CommandLineUtils.Tests/CommandLineApplicationTests.cs b/test/CommandLineUtils.Tests/CommandLineApplicationTests.cs
@@ -720,7 +720,7 @@ public void NestedInheritedOptions()
         [InlineData(new[] { "-t", "val", "--", "a", "--", "b" }, new[] { "a", "--", "b" }, "val")]
         [InlineData(new[] { "--", "--help" }, new[] { "--help" }, null)]
         [InlineData(new[] { "--", "--version" }, new[] { "--version" }, null)]
-        public void ArgumentSeparator(string[] input, string[] expectedRemaining, string topLevelValue)
+        public void ArgumentSeparator(string[] input, string[] expectedRemaining, string? topLevelValue)
         {
             var app = new CommandLineApplication
             {
@@ -1047,7 +1047,7 @@ public void ThrowsExceptionOnEmptyCommandOrArgument()
         [InlineData(null)]
         [InlineData("")]
         [InlineData("-")]
-        public void ThrowsExceptionOnInvalidArgument(string inputOption)
+        public void ThrowsExceptionOnInvalidArgument(string? inputOption)
         {
             var app = new CommandLineApplication();
 
diff --git a/test/CommandLineUtils.Tests/CommandLineProcessorTests.cs b/test/CommandLineUtils.Tests/CommandLineProcessorTests.cs
@@ -25,7 +25,7 @@ public class CommandLineProcessorTests
         [InlineData(new[] { "-af", "Path.txt" }, true, false, false, "Path.txt")]
         [InlineData(new[] { "-f:Path.txt" }, false, false, false, "Path.txt")]
         [InlineData(new[] { "-a", "-c", "-f", "Path.txt" }, true, false, true, "Path.txt")]
-        public void CanParseClusteredOptions(string[] input, bool a, bool b, bool c, string f)
+        public void CanParseClusteredOptions(string[] input, bool a, bool b, bool c, string? f)
         {
             var app = new CommandLineApplication
             {
@@ -62,7 +62,7 @@ public void CanParseClusteredOptionMultipleTimes()
         [InlineData("-vl=diag", "diag")]
         [InlineData("-vl", null)]
         [InlineData("-lv", null)]
-        public void ItClustersSingleOrNoValueOptions(string input, string expectedLogValue)
+        public void ItClustersSingleOrNoValueOptions(string input, string? expectedLogValue)
         {
             var app = new CommandLineApplication
             {
@@ -252,7 +252,7 @@ public void CanUseSingleDashAsArgumentValue()
         [InlineData("--log: ", " ")]
         [InlineData("--log:verbose", "verbose")]
         [InlineData("--log=verbose", "verbose")]
-        public void CanParseSingleOrNoValueParameter(string input, string expected)
+        public void CanParseSingleOrNoValueParameter(string input, string? expected)
         {
             var app = new CommandLineApplication();
             var opt = app.Option("--log", "Log level", CommandOptionType.SingleOrNoValue);
@@ -266,7 +266,7 @@ public void CanParseSingleOrNoValueParameter(string input, string expected)
         [InlineData(new[] { "--param1" }, null, null)]
         [InlineData(new[] { "--param1", "--param2", "p2" }, null, "p2")]
         [InlineData(new[] { "--param1:p1", "--param2", "p2" }, "p1", "p2")]
-        public void CanParseSingleOrNoValueParameters(string[] args, string param1, string param2)
+        public void CanParseSingleOrNoValueParameters(string[] args, string? param1, string? param2)
         {
             var app = new CommandLineApplication();
             var opt1 = app.Option("--param1", "param1", CommandOptionType.SingleOrNoValue);
diff --git a/test/CommandLineUtils.Tests/CommandOptionTests.cs b/test/CommandLineUtils.Tests/CommandOptionTests.cs
@@ -28,7 +28,7 @@ public class CommandOptionTests
         [InlineData("--name=<VALUE>", null, null, "name", "VALUE")]
         [InlineData("-a:<VALUE> --name:<VALUE>", "a", null, "name", "VALUE")]
         [InlineData("-a=<VALUE> --name=<VALUE>", "a", null, "name", "VALUE")]
-        public void ItParsesSingleValueTemplate(string template, string shortName, string symbolName, string longName, string valueName)
+        public void ItParsesSingleValueTemplate(string template, string? shortName, string? symbolName, string? longName, string? valueName)
         {
             var opt = new CommandOption(template, CommandOptionType.SingleValue);
             Assert.Equal(shortName, opt.ShortName);
@@ -40,7 +40,7 @@ public void ItParsesSingleValueTemplate(string template, string shortName, strin
         [Theory]
         [InlineData("--name[:<VALUE>]", null, null, "name", "VALUE")]
         [InlineData("--name[=<VALUE>]", null, null, "name", "VALUE")]
-        public void ItParsesSingleOrNoValueTemplate(string template, string shortName, string symbolName, string longName, string valueName)
+        public void ItParsesSingleOrNoValueTemplate(string template, string? shortName, string? symbolName, string longName, string valueName)
         {
             var opt = new CommandOption(template, CommandOptionType.SingleOrNoValue);
             Assert.Equal(shortName, opt.ShortName);
diff --git a/test/CommandLineUtils.Tests/CustomValidationAttributeTest.cs b/test/CommandLineUtils.Tests/CustomValidationAttributeTest.cs
@@ -12,11 +12,11 @@ public class CustomValidationAttributeTest
         [InlineData(null)]
         [InlineData("-c", "red")]
         [InlineData("-c", "blue")]
-        public void CustomValidationAttributePasses(params string[] args)
+        public void CustomValidationAttributePasses(params string?[] args)
         {
             var app = new CommandLineApplication<RedBlueProgram>();
             app.Conventions.UseDefaultConventions();
-            var result = app.Parse(args ?? System.Array.Empty<string>());
+            var result = app.Parse(args ?? []);
             Assert.Equal(ValidationResult.Success, result.SelectedCommand.GetValidationResult());
             var program = Assert.IsType<CommandLineApplication<RedBlueProgram>>(result.SelectedCommand);
             Assert.Same(app, program);
@@ -30,7 +30,7 @@ public void CustomValidationAttributePasses(params string[] args)
         [InlineData("-c", "")]
         [InlineData("-c", null)]
         [InlineData("-c", "green")]
-        public void CustomValidationAttributeFails(params string[] args)
+        public void CustomValidationAttributeFails(params string?[] args)
         {
             var app = new CommandLineApplication<RedBlueProgram>();
             app.Conventions.UseAttributes();
diff --git a/test/CommandLineUtils.Tests/DefaultHelpTextGeneratorTests.cs b/test/CommandLineUtils.Tests/DefaultHelpTextGeneratorTests.cs
@@ -288,7 +288,7 @@ public class MyApp
         [InlineData("--help", "--help", "  --help      Show help information.", "  Subcommand  ")]
         [InlineData("-?", "-?", "  -?          Show help information.", "  Subcommand  ")]
         [InlineData(null, "-?|-h|--help", "  -?|-h|--help  Show help information.", "  Subcommand    ")]
-        public void ShowHelpWithSubcommands(string helpOption, string expectedHintText, string expectedOptionsText,
+        public void ShowHelpWithSubcommands(string? helpOption, string expectedHintText, string expectedOptionsText,
             string expectedCommandsText)
         {
             var app = new CommandLineApplication { Name = "test" };
diff --git a/test/CommandLineUtils.Tests/ExecuteMethodConventionTests.cs b/test/CommandLineUtils.Tests/ExecuteMethodConventionTests.cs
@@ -133,11 +133,11 @@ public async Task ItExecutesAsyncMethod()
             var app = new CommandLineApplication<ProgramWithAsyncOnExecute>(console);
             app.Conventions.UseOnExecuteMethodFromModel();
             var executeTask = app.ExecuteAsync(Array.Empty<string>());
-            await ProgramWithAsyncOnExecute.ExecuteStarted.Task.ConfigureAwait(false);
+            await ProgramWithAsyncOnExecute.ExecuteStarted.Task.ConfigureAwait(true);
             Assert.False(app.Model.Token.IsCancellationRequested);
             Assert.NotEqual(CancellationToken.None, app.Model.Token);
             console.RaiseCancelKeyPress();
-            var result = await executeTask.ConfigureAwait(false);
+            var result = await executeTask.ConfigureAwait(true);
             Assert.Equal(4, result);
             Assert.True(app.Model.Token.IsCancellationRequested);
         }
diff --git a/test/CommandLineUtils.Tests/LegalFilePathAttributeTests.cs b/test/CommandLineUtils.Tests/LegalFilePathAttributeTests.cs
@@ -46,7 +46,7 @@ public void ValidatesLegalFilePaths(string filePath)
         [InlineData(null)]
         [InlineData("")]
         [InlineData("\0")]
-        public void FailsInvalidLegalFilePaths(string filePath)
+        public void FailsInvalidLegalFilePaths(string? filePath)
         {
             var console = new TestConsole(_output);
             Assert.NotEqual(0, CommandLineApplication.Execute<App>(console, filePath));
diff --git a/test/CommandLineUtils.Tests/McMaster.Extensions.CommandLineUtils.Tests.csproj b/test/CommandLineUtils.Tests/McMaster.Extensions.CommandLineUtils.Tests.csproj
@@ -1,7 +1,7 @@
 ﻿<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net6.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
     <!-- Once xunit supports nullable reference types, I might reconsider -->
     <Nullable>annotations</Nullable>
   </PropertyGroup>
@@ -11,14 +11,22 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.collector" Version="3.1.1" />
+    <PackageReference Include="coverlet.collector" Version="6.0.4">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
     <PackageReference Include="McMaster.Extensions.Xunit" Version="0.1.0" />
-    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="6.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
-    <PackageReference Include="FluentAssertions" Version="6.2.0" />
-    <PackageReference Include="Moq" Version="4.16.1" />
-    <PackageReference Include="xunit" Version="2.4.1" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="9.0.10" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
+    <PackageReference Include="FluentAssertions" Version="8.8.0" />
+    <PackageReference Include="Moq" Version="4.20.72" />
+    <PackageReference Include="System.Net.Http" Version="4.3.4" />
+    <PackageReference Include="System.Text.RegularExpressions" Version="4.3.1" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
 
   <ItemGroup>
diff --git a/test/CommandLineUtils.Tests/StringExtensionsTests.cs b/test/CommandLineUtils.Tests/StringExtensionsTests.cs
@@ -27,7 +27,7 @@ public class StringExtensionsTests
         [InlineData("field___", "field")]
         [InlineData("m_field", "m-field")]
         [InlineData("m_Field", "m-field")]
-        public void ToKebabCase(string input, string expected)
+        public void ToKebabCase(string? input, string? expected)
         {
             Assert.Equal(expected, input.ToKebabCase());
         }
@@ -39,7 +39,7 @@ public void ToKebabCase(string input, string expected)
         [InlineData("word", "WORD")]
         [InlineData("_field", "FIELD")]
         [InlineData("MSBuildTask", "MSBUILD_TASK")]
-        public void ToConstantCase(string input, string expected)
+        public void ToConstantCase(string? input, string? expected)
         {
             Assert.Equal(expected, input.ToConstantCase());
         }
diff --git a/test/CommandLineUtils.Tests/ValidateMethodConventionTests.cs b/test/CommandLineUtils.Tests/ValidateMethodConventionTests.cs
@@ -102,7 +102,7 @@ private ValidationResult OnValidate(ValidationContext context, CommandLineContex
         [InlineData("-m 111 subcommand", null)]
         [InlineData("subcommand -s 111 -e 123", null)]
         [InlineData("-m 111 subcommand -s 100 -e 123", null)]
-        public void ValidatorShouldGetDeserailizedModelInSubcommands(string args, string error)
+        public void ValidatorShouldGetDeserializedModelInSubcommands(string args, string? error)
         {
             var app = new CommandLineApplication<MainValidate>();
             app.Conventions.UseDefaultConventions();
diff --git a/test/CommandLineUtils.Tests/ValidationTests.cs b/test/CommandLineUtils.Tests/ValidationTests.cs
@@ -304,7 +304,7 @@ public void DoesNotValidate_WhenShowingInfo()
             app.HelpOption();
             var errorMessage = "Version arg is required";
             app.Argument("version", "Arg").IsRequired(errorMessage: errorMessage);
-            app.OnValidationError((_) => Assert.False(true, "Validation callbacks should not be executed"));
+            app.OnValidationError((_) => Assert.Fail("Validation callbacks should not be executed"));
 
             Assert.Equal(0, app.Execute("--help"));
             Assert.DoesNotContain(errorMessage, sb.ToString());
diff --git a/test/CommandLineUtils.Tests/ValueParserProviderTests.cs b/test/CommandLineUtils.Tests/ValueParserProviderTests.cs
@@ -141,17 +141,32 @@ public void Dispose()
 
         // Workaround https://github.com/dotnet/roslyn/issues/33199 https://github.com/xunit/xunit/issues/1897
 #nullable disable
+        public static IEnumerable<object[]> GetDoublePointSymbolsData()
+        {
+            using (new InCulture(CultureInfo.InvariantCulture))
+            {
+                var format = CultureInfo.CurrentCulture.NumberFormat;
+                return
+                [
+                    [format.PositiveInfinitySymbol, double.PositiveInfinity],
+                    [format.NegativeInfinitySymbol, double.NegativeInfinity],
+                    [format.NaNSymbol, double.NaN]
+                ];
+            }
+        }
+
+
         public static IEnumerable<object[]> GetFloatingPointSymbolsData()
         {
             using (new InCulture(CultureInfo.InvariantCulture))
             {
                 var format = CultureInfo.CurrentCulture.NumberFormat;
-                return new[]
-                {
-                    new object[] { format.PositiveInfinitySymbol, float.PositiveInfinity },
-                    new object[] { format.NegativeInfinitySymbol, float.NegativeInfinity },
-                    new object[] { format.NaNSymbol, float.NaN},
-                };
+                return
+                [
+                    [format.PositiveInfinitySymbol, float.PositiveInfinity],
+                    [format.NegativeInfinitySymbol, float.NegativeInfinity],
+                    [format.NaNSymbol, float.NaN]
+                ];
             }
         }
 #nullable enable
@@ -267,11 +282,11 @@ public void ParsesFloatNullable(string arg, float? result)
         }
 
         [Theory]
-        [InlineData("0.0", 0.0)]
-        [InlineData("123456789.987654321", 123456789.987654321)]
-        [InlineData("-123.456", -123.456)]
+        [InlineData("0.0", 0.0D)]
+        [InlineData("123456789.987654321", 123456789.987654321D)]
+        [InlineData("-123.456", -123.456D)]
         [InlineData("-1E10", -1E10)]
-        [MemberData(nameof(GetFloatingPointSymbolsData))]
+        [MemberData(nameof(GetDoublePointSymbolsData))]
         [InlineData("", null)]
         public void ParsesDoubleNullable(string arg, double? result)
         {
@@ -401,8 +416,8 @@ public void ParsesStringList()
         public void ParsesStringSet()
         {
             var parsed = CommandLineParser.ParseArgs<Program>("--string-set", "first", "--string-set", "second");
-            Assert.Contains("first", parsed.StringSet);
-            Assert.Contains("second", parsed.StringSet);
+            Assert.Contains("first", parsed.StringSet!);
+            Assert.Contains("second", parsed.StringSet!);
         }
 
         [Theory]
@@ -420,7 +435,7 @@ public void ParsesEnum(Color color)
         [InlineData("--value-tuple:", "")]
         [InlineData("--value-tuple: ", " ")]
         [InlineData("--value-tuple:path", "path")]
-        public void ParsesValueTupleOfBoolAndType(string input, string expected)
+        public void ParsesValueTupleOfBoolAndType(string input, string? expected)
         {
             var parsed = CommandLineParser.ParseArgs<Program>(input);
             Assert.True(parsed.ValueTuple.HasValue);
@@ -527,7 +542,7 @@ public void ParsesBoolArray(int repeat)
             var parsed = CommandLineParser.ParseArgs<Program>(args.ToArray());
             Assert.NotNull(parsed.Flags);
             Assert.Equal(repeat, parsed.Flags?.Length);
-            Assert.All(parsed.Flags, value => Assert.True(value));
+            Assert.All(parsed.Flags!, Assert.True);
         }
 
         [Theory]
@@ -631,7 +646,7 @@ public void ThrowsIfNoValueParserProviderIsAvailable()
         [InlineData(typeof(Color), null, default(Color))]
         [InlineData(typeof(Color?), "", null)]
         [MemberData(nameof(TupleData))]
-        public void ItParsesParamofT(Type type, string input, object expected)
+        public void ItParsesParamofT(Type type, string? input, object? expected)
         {
             using (new InCulture(CultureInfo.InvariantCulture))
             {
diff --git a/test/Hosting.CommandLine.Tests/McMaster.Extensions.Hosting.CommandLine.Tests.csproj b/test/Hosting.CommandLine.Tests/McMaster.Extensions.Hosting.CommandLine.Tests.csproj
@@ -1,20 +1,26 @@
 ﻿<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>net8.0;net6.0</TargetFrameworks>
+    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
   </PropertyGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\..\src\Hosting.CommandLine\McMaster.Extensions.Hosting.CommandLine.csproj" />
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.collector" Version="3.1.1" />
-    <PackageReference Include="Microsoft.Extensions.Hosting" Version="6.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.0.0" />
-    <PackageReference Include="Moq" Version="4.16.1" />
-    <PackageReference Include="xunit" Version="2.4.1" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3" />
+    <PackageReference Include="coverlet.collector" Version="6.0.4">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="Microsoft.Extensions.Hosting" Version="9.0.10" />
+    <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="9.0.10" />
+    <PackageReference Include="Moq" Version="4.20.72" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
 
   <ItemGroup>

Original file line number	Diff line number	Diff line change
`@@ -94,7 +94,7 @@ private void OnExecute() { }`
`94`	`94`	`[InlineData("email", 1)]`
`95`	`95`	`[InlineData("email@email@email", 1)]`
`96`	`96`	`[InlineData("[email protected]", 0)]`
`97`		`- public void ValidatesEmailArgument(string email, int exitCode)`
	`97`	`+ public void ValidatesEmailArgument(string? email, int exitCode)`
`98`	`98`	`{`
`99`	`99`	`Assert.Equal(exitCode, CommandLineApplication.Execute<EmailArgumentApp>(new TestConsole(_output), email));`
`100`	`100`	`}`
Original file line number	Diff line number	Diff line change
`@@ -197,7 +197,7 @@ private class HelpClass`
`197`	`197`	`{`
`198`	`198`	`private void OnExecute()`
`199`	`199`	`{`
`200`		`- Assert.True(false, "This should not execute");`
	`200`	`+ Assert.Fail("This should not execute");`
`201`	`201`	`}`
`202`	`202`	`}`
`203`	`203`
Original file line number	Diff line number	Diff line change
`@@ -720,7 +720,7 @@ public void NestedInheritedOptions()`
`720`	`720`	`[InlineData(new[] { "-t", "val", "--", "a", "--", "b" }, new[] { "a", "--", "b" }, "val")]`
`721`	`721`	`[InlineData(new[] { "--", "--help" }, new[] { "--help" }, null)]`
`722`	`722`	`[InlineData(new[] { "--", "--version" }, new[] { "--version" }, null)]`
`723`		`- public void ArgumentSeparator(string[] input, string[] expectedRemaining, string topLevelValue)`
	`723`	`+ public void ArgumentSeparator(string[] input, string[] expectedRemaining, string? topLevelValue)`
`724`	`724`	`{`
`725`	`725`	`var app = new CommandLineApplication`
`726`	`726`	`{`
`@@ -1047,7 +1047,7 @@ public void ThrowsExceptionOnEmptyCommandOrArgument()`
`1047`	`1047`	`[InlineData(null)]`
`1048`	`1048`	`[InlineData("")]`
`1049`	`1049`	`[InlineData("-")]`
`1050`		`- public void ThrowsExceptionOnInvalidArgument(string inputOption)`
	`1050`	`+ public void ThrowsExceptionOnInvalidArgument(string? inputOption)`
`1051`	`1051`	`{`
`1052`	`1052`	`var app = new CommandLineApplication();`
`1053`	`1053`
Original file line number	Diff line number	Diff line change
`@@ -25,7 +25,7 @@ public class CommandLineProcessorTests`
`25`	`25`	`[InlineData(new[] { "-af", "Path.txt" }, true, false, false, "Path.txt")]`
`26`	`26`	`[InlineData(new[] { "-f:Path.txt" }, false, false, false, "Path.txt")]`
`27`	`27`	`[InlineData(new[] { "-a", "-c", "-f", "Path.txt" }, true, false, true, "Path.txt")]`
`28`		`- public void CanParseClusteredOptions(string[] input, bool a, bool b, bool c, string f)`
	`28`	`+ public void CanParseClusteredOptions(string[] input, bool a, bool b, bool c, string? f)`
`29`	`29`	`{`
`30`	`30`	`var app = new CommandLineApplication`
`31`	`31`	`{`
`@@ -62,7 +62,7 @@ public void CanParseClusteredOptionMultipleTimes()`
`62`	`62`	`[InlineData("-vl=diag", "diag")]`
`63`	`63`	`[InlineData("-vl", null)]`
`64`	`64`	`[InlineData("-lv", null)]`
`65`		`- public void ItClustersSingleOrNoValueOptions(string input, string expectedLogValue)`
	`65`	`+ public void ItClustersSingleOrNoValueOptions(string input, string? expectedLogValue)`
`66`	`66`	`{`
`67`	`67`	`var app = new CommandLineApplication`
`68`	`68`	`{`
`@@ -252,7 +252,7 @@ public void CanUseSingleDashAsArgumentValue()`
`252`	`252`	`[InlineData("--log: ", " ")]`
`253`	`253`	`[InlineData("--log:verbose", "verbose")]`
`254`	`254`	`[InlineData("--log=verbose", "verbose")]`
`255`		`- public void CanParseSingleOrNoValueParameter(string input, string expected)`
	`255`	`+ public void CanParseSingleOrNoValueParameter(string input, string? expected)`
`256`	`256`	`{`
`257`	`257`	`var app = new CommandLineApplication();`
`258`	`258`	`var opt = app.Option("--log", "Log level", CommandOptionType.SingleOrNoValue);`
`@@ -266,7 +266,7 @@ public void CanParseSingleOrNoValueParameter(string input, string expected)`
`266`	`266`	`[InlineData(new[] { "--param1" }, null, null)]`
`267`	`267`	`[InlineData(new[] { "--param1", "--param2", "p2" }, null, "p2")]`
`268`	`268`	`[InlineData(new[] { "--param1:p1", "--param2", "p2" }, "p1", "p2")]`
`269`		`- public void CanParseSingleOrNoValueParameters(string[] args, string param1, string param2)`
	`269`	`+ public void CanParseSingleOrNoValueParameters(string[] args, string? param1, string? param2)`
`270`	`270`	`{`
`271`	`271`	`var app = new CommandLineApplication();`
`272`	`272`	`var opt1 = app.Option("--param1", "param1", CommandOptionType.SingleOrNoValue);`
Original file line number	Diff line number	Diff line change
`@@ -288,7 +288,7 @@ public class MyApp`
`288`	`288`	`[InlineData("--help", "--help", " --help Show help information.", " Subcommand ")]`
`289`	`289`	`[InlineData("-?", "-?", " -? Show help information.", " Subcommand ")]`
`290`	`290`	`[InlineData(null, "-?\|-h\|--help", " -?\|-h\|--help Show help information.", " Subcommand ")]`
`291`		`- public void ShowHelpWithSubcommands(string helpOption, string expectedHintText, string expectedOptionsText,`
	`291`	`+ public void ShowHelpWithSubcommands(string? helpOption, string expectedHintText, string expectedOptionsText,`
`292`	`292`	`string expectedCommandsText)`
`293`	`293`	`{`
`294`	`294`	`var app = new CommandLineApplication { Name = "test" };`