cleanup: Restore nullable annotations checks in tests and cleanup dead code

Author: natemcmaster

src/CommandLineUtils/IO/Pager.cs

@@ -122,8 +122,11 @@ public void Kill()
                     FileName = "less",
                     Arguments = ArgumentEscaper.EscapeAndConcatenate(args),
                     RedirectStandardInput = true,
-#if NET46_OR_GREATER
+#if NET472_OR_GREATER
                     UseShellExecute = false,
+#elif NET6_0_OR_GREATER
+#else
+#error Target framework misconfiguration
 #endif
                 }
             };

src/CommandLineUtils/Properties/NullabilityHelpers.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Nate McMaster.
+// Copyright (c) Nate McMaster.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
@@ -158,6 +158,7 @@ public void ThrowsForUnknownOnExecuteTypes()
             var ex = Assert.Throws<InvalidOperationException>(
                 () => CommandLineApplication.Execute<ExecuteWithUnknownTypes>());
             var method = typeof(ExecuteWithUnknownTypes).GetMethod("OnExecute", BindingFlags.Instance | BindingFlags.NonPublic);
+            Assert.NotNull(method);
             var param = Assert.Single(method.GetParameters());
             Assert.Equal(Strings.UnsupportedParameterTypeOnMethod(method.Name, param), ex.Message);
         }

test/CommandLineUtils.Tests/CommandLineApplicationExecutorTests.cs

@@ -492,7 +492,8 @@ public void AllowNoThrowBehaviorOnUnexpectedOptionAfterSubcommand()
             // (does not throw)
             app.Execute("k", "run", unexpectedOption);
             Assert.Empty(testCmd.RemainingArguments);
-            var arg = Assert.Single(subCmd?.RemainingArguments);
+            Assert.NotNull(subCmd);
+            var arg = Assert.Single(subCmd.RemainingArguments);
             Assert.Equal(unexpectedOption, arg);
         }
 
@@ -697,9 +698,10 @@ public void NestedInheritedOptions()
             Assert.Contains(subcmd1.GetOptions(), o => o.LongName == "nest1");
             Assert.Contains(subcmd1.GetOptions(), o => o.LongName == "global");
 
-            Assert.Contains(subcmd2?.GetOptions(), o => o.LongName == "nest2");
-            Assert.Contains(subcmd2?.GetOptions(), o => o.LongName == "nest1");
-            Assert.Contains(subcmd2?.GetOptions(), o => o.LongName == "global");
+            Assert.NotNull(subcmd2);
+            Assert.Contains(subcmd2.GetOptions(), o => o.LongName == "nest2");
+            Assert.Contains(subcmd2.GetOptions(), o => o.LongName == "nest1");
+            Assert.Contains(subcmd2.GetOptions(), o => o.LongName == "global");
 
             Assert.ThrowsAny<CommandParsingException>(() => app.Execute("--nest2", "N2", "--nest1", "N1", "-g", "G"));
             Assert.ThrowsAny<CommandParsingException>(() => app.Execute("lvl1", "--nest2", "N2", "--nest1", "N1", "-g", "G"));

test/CommandLineUtils.Tests/CommandLineApplicationTests.cs

@@ -34,7 +34,7 @@ public void CustomValidationAttributeFails(params string?[] args)
         {
             var app = new CommandLineApplication<RedBlueProgram>();
             app.Conventions.UseAttributes();
-            var result = app.Parse(args);
+            var result = app.Parse(args!);
             var validationResult = result.SelectedCommand.GetValidationResult();
             Assert.NotEqual(ValidationResult.Success, validationResult);
             var program = Assert.IsType<CommandLineApplication<RedBlueProgram>>(result.SelectedCommand);

test/CommandLineUtils.Tests/CustomValidationAttributeTest.cs

@@ -3,7 +3,7 @@
 
 // This file has been modified from the original form. See Notice.txt in the project root for more information.
 
-#if NETCOREAPP3_1_OR_GREATER
+#if NET6_0_OR_GREATER
 using System.IO;
 using Xunit;
 

test/CommandLineUtils.Tests/DotNetExeTests.cs

@@ -3,8 +3,6 @@
   <PropertyGroup>
     <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
     <TargetFrameworks Condition="'$(TestFullFramework)' != 'false'">$(TargetFrameworks);net472</TargetFrameworks>
-    <!-- Once xunit supports nullable reference types, I might reconsider -->
-    <Nullable>annotations</Nullable>
   </PropertyGroup>
 
   <ItemGroup>

test/CommandLineUtils.Tests/McMaster.Extensions.CommandLineUtils.Tests.csproj

@@ -71,7 +71,7 @@ private class EmptyShortName
         public void CanSetShortNameToEmptyString()
         {
             var app = Create<EmptyShortName>();
-            Assert.All(app.Options, o => Assert.Empty(o.ShortName));
+            Assert.All(app.Options, o => Assert.True(o.ShortName is null or ""));
         }
 
         private class AmbiguousShortOptionName
@@ -465,7 +465,7 @@ public void ApplyingOptionConventionTwice_WithLongOnlyOptions_DoesNotThrow()
             Assert.Single(app.Options, o => o.LongName == "count");
 
             // Verify short names are empty
-            Assert.All(app.Options, o => Assert.Empty(o.ShortName));
+            Assert.All(app.Options, o => Assert.True(o.ShortName is null or ""));
         }
 
         #endregion