More XML docs and cleanup (#1348)

jonsequitur · web-flow · commit 82e8198b3cf7 · 2021-07-10T11:35:49.000-07:00
* wip

* XML comments and cleanup
diff --git a/src/System.CommandLine/Binding/ArgumentConversionResult.cs b/src/System.CommandLine/Binding/ArgumentConversionResult.cs
@@ -14,10 +14,10 @@ private protected ArgumentConversionResult(IArgument argument)
 
         internal string? ErrorMessage { get; set; }
 
-        internal static FailedArgumentConversionResult Failure(IArgument argument, string error) => new FailedArgumentConversionResult(argument, error);
+        internal static FailedArgumentConversionResult Failure(IArgument argument, string error) => new(argument, error);
 
-        public static SuccessfulArgumentConversionResult Success(IArgument argument, object? value) => new SuccessfulArgumentConversionResult(argument, value);
+        public static SuccessfulArgumentConversionResult Success(IArgument argument, object? value) => new(argument, value);
 
-        internal static NoArgumentConversionResult None(IArgument argument) => new NoArgumentConversionResult(argument);
+        internal static NoArgumentConversionResult None(IArgument argument) => new(argument);
     }
 }
diff --git a/src/System.CommandLine/Binding/ArgumentConversionResultSet.cs b/src/System.CommandLine/Binding/ArgumentConversionResultSet.cs
diff --git a/src/System.CommandLine/Binding/Binder.cs b/src/System.CommandLine/Binding/Binder.cs
@@ -68,18 +68,18 @@ internal static bool CanBeBoundFromScalarValue(this Type type)
                 {
                     return type.GetGenericTypeDefinition() switch
                     {
-                        Type enumerable when enumerable == typeof(IEnumerable<>) => GetEmptyEnumerable(itemType),
-                        Type list when list == typeof(List<>) => GetEmptyList(itemType),
-                        Type array when array == typeof(IList<>) || 
-                                        array == typeof(ICollection<>) => CreateEmptyArray(itemType),
+                        { } enumerable when enumerable == typeof(IEnumerable<>) => GetEmptyEnumerable(itemType),
+                        { } list when list == typeof(List<>) => GetEmptyList(itemType),
+                        { } array when array == typeof(IList<>) || 
+                                       array == typeof(ICollection<>) => CreateEmptyArray(itemType),
                         _ => null
                     };
                 }
             }
 
             return type switch
             {
-                Type nonGeneric 
+                { } nonGeneric 
                 when nonGeneric == typeof(IList) ||
                      nonGeneric == typeof(ICollection) ||
                      nonGeneric == typeof(IEnumerable)
diff --git a/src/System.CommandLine/Binding/ConstructorDescriptor.cs b/src/System.CommandLine/Binding/ConstructorDescriptor.cs
@@ -32,6 +32,7 @@ internal object Invoke(IReadOnlyCollection<object?> parameters)
             return _constructorInfo.Invoke(parameters.ToArray());
         }
 
+        /// <inheritdoc />
         public override string ToString() =>
             $"{Parent} ({string.Join(", ", ParameterDescriptors)})";
     }
diff --git a/src/System.CommandLine/Binding/HandlerDescriptor.cs b/src/System.CommandLine/Binding/HandlerDescriptor.cs
@@ -21,6 +21,7 @@ public abstract class HandlerDescriptor : IMethodDescriptor
 
         protected abstract IEnumerable<ParameterDescriptor> InitializeParameterDescriptors();
 
+        /// <inheritdoc />
         public override string ToString() =>
             $"{Parent} ({string.Join(", ", ParameterDescriptors)})";
 
diff --git a/src/System.CommandLine/Binding/ModelBinder.cs b/src/System.CommandLine/Binding/ModelBinder.cs
@@ -24,10 +24,10 @@ internal ModelBinder(IValueDescriptor valueDescriptor)
         public bool EnforceExplicitBinding { get; set; }
 
         internal Dictionary<IValueDescriptor, IValueSource> ConstructorArgumentBindingSources { get; } =
-            new Dictionary<IValueDescriptor, IValueSource>();
+            new();
 
         internal Dictionary<IValueDescriptor, IValueSource> MemberBindingSources { get; } =
-            new Dictionary<IValueDescriptor, IValueSource>();
+            new();
 
         // Consider deprecating in favor or BindingConfiguration/BindingContext attach validatation. Then make internal.
         // Or at least rename to "ConfigureBinding" or similar
@@ -133,7 +133,7 @@ private bool ShortCutTheBinding()
             {
                 return (false, null, false);
             }
-            if (!(newInstance is null))
+            if (newInstance is not null)
             {
                 nonDefaultsUsed = UpdateInstanceInternalNotifyIfNonDefaultsUsed(newInstance, bindingContext);
             }
@@ -333,7 +333,7 @@ protected IValueDescriptor FindModelPropertyDescriptor(Type propertyType, string
 
         private ConstructorInfo FindConstructorOrThrow(ParameterInfo parameter, string message)
         {
-            if (!(parameter.Member is ConstructorInfo constructor))
+            if (parameter.Member is not ConstructorInfo constructor)
             {
                 throw new ArgumentException(paramName: nameof(parameter),
                       message: message);
diff --git a/src/System.CommandLine/Binding/ModelDescriptor.cs b/src/System.CommandLine/Binding/ModelDescriptor.cs
@@ -15,7 +15,7 @@ public class ModelDescriptor
             | BindingFlags.Public
             | BindingFlags.Instance;
 
-        private static readonly ConcurrentDictionary<Type, ModelDescriptor> _modelDescriptors = new ConcurrentDictionary<Type, ModelDescriptor>();
+        private static readonly ConcurrentDictionary<Type, ModelDescriptor> _modelDescriptors = new();
 
         private List<PropertyDescriptor>? _propertyDescriptors;
         private List<ConstructorDescriptor>? _constructorDescriptors;
@@ -41,6 +41,7 @@ protected ModelDescriptor(Type modelType)
 
         public Type ModelType { get; }
 
+        /// <inheritdoc />
         public override string ToString() => $"{ModelType.Name}";
 
         public static ModelDescriptor FromType<T>() =>
diff --git a/src/System.CommandLine/Binding/PropertyDescriptor.cs b/src/System.CommandLine/Binding/PropertyDescriptor.cs
@@ -34,6 +34,7 @@ public void SetValue(object? instance, object? value)
             _propertyInfo.SetValue(instance, value);
         }
 
+        /// <inheritdoc />
         public override string ToString() => $"{ValueType.Name} {Path}";
     }
 }
diff --git a/src/System.CommandLine/Binding/SpecificSymbolValueSource.cs b/src/System.CommandLine/Binding/SpecificSymbolValueSource.cs
@@ -23,15 +23,15 @@ public bool TryGetValue(IValueDescriptor valueDescriptor,
             {
                 case IOption option:
                     var optionResult = bindingContext?.ParseResult.FindResultFor(option);
-                    if (!(optionResult is null))
+                    if (optionResult is not null)
                     {
                         boundValue = optionResult.GetValueOrDefault();
                         return true;
                     }
                     break;
                 case IArgument argument:
                     var argumentResult = bindingContext?.ParseResult.FindResultFor(argument);
-                    if (!(argumentResult is null))
+                    if (argumentResult is not null)
                     {
                         boundValue = argumentResult.GetValueOrDefault();
                         return true;
diff --git a/src/System.CommandLine/Builder/CommandLineBuilder.cs b/src/System.CommandLine/Builder/CommandLineBuilder.cs
@@ -12,7 +12,7 @@ namespace System.CommandLine.Builder
 {
     public class CommandLineBuilder : CommandBuilder
     {
-        private readonly List<(InvocationMiddleware middleware, int order)> _middlewareList = new List<(InvocationMiddleware middleware, int order)>();
+        private readonly List<(InvocationMiddleware middleware, int order)> _middlewareList = new();
 
         public CommandLineBuilder(Command? rootCommand = null)
             : base(rootCommand ?? new RootCommand())
diff --git a/src/System.CommandLine/Builder/CommandLineBuilderExtensions.cs b/src/System.CommandLine/Builder/CommandLineBuilderExtensions.cs
@@ -324,7 +324,7 @@ public static CommandLineBuilder UseExceptionHandler(
 
             void Default(Exception exception, InvocationContext context)
             {
-                if (!(exception is OperationCanceledException))
+                if (exception is not OperationCanceledException)
                 {
                     context.Console.ResetTerminalForegroundColor();
                     context.Console.SetTerminalForegroundRed();
diff --git a/src/System.CommandLine/Collections/AliasedSet.cs b/src/System.CommandLine/Collections/AliasedSet.cs
@@ -14,11 +14,11 @@ namespace System.CommandLine.Collections
     public abstract class AliasedSet<T> : IReadOnlyList<T>
         where T : class
     {
-        private protected readonly Dictionary<string, T> ItemsByAlias = new Dictionary<string, T>();
+        private protected readonly Dictionary<string, T> ItemsByAlias = new();
 
-        private protected List<T> Items { get; } = new List<T>();
+        private protected List<T> Items { get; } = new();
 
-        private protected HashSet<T> DirtyItems { get; } = new HashSet<T>();
+        private protected HashSet<T> DirtyItems { get; } = new();
         
         /// <inheritdoc/>
         public int Count => Items.Count;
diff --git a/src/System.CommandLine/CommandLineConfiguration.cs b/src/System.CommandLine/CommandLineConfiguration.cs
@@ -17,7 +17,8 @@ namespace System.CommandLine
     /// </summary>
     public class CommandLineConfiguration
     {
-        private readonly SymbolSet _symbols = new SymbolSet();
+        private readonly SymbolSet _symbols = new();
+        private Func<BindingContext, IHelpBuilder>? _helpBuilderFactory;
 
         /// <summary>
         /// Initializes a new instance of the CommandLineConfiguration class.
@@ -60,17 +61,18 @@ public CommandLineConfiguration(
             else
             {
                 // Reuse existing auto-generated root command, if one is present, to prevent repeated mutations
-                RootCommand? parentRootCommand = 
+                RootCommand? parentRootCommand =
                     symbols.SelectMany(s => s.Parents)
-                           .OfType<RootCommand>()
-                           .FirstOrDefault();
+                        .OfType<RootCommand>()
+                        .FirstOrDefault();
 
                 if (parentRootCommand is null)
                 {
                     parentRootCommand = new RootCommand();
 
-                    foreach (var symbol in symbols)
+                    for (var i = 0; i < symbols.Count; i++)
                     {
+                        var symbol = symbols[i];
                         parentRootCommand.Add(symbol);
                     }
                 }
@@ -87,19 +89,13 @@ public CommandLineConfiguration(
             Resources = resources ?? Resources.Instance;
             ResponseFileHandling = responseFileHandling;
             Middleware = middlewarePipeline ?? new List<InvocationMiddleware>();
-            HelpBuilderFactory = helpBuilderFactory ?? (context => 
-            {
-                int maxWidth = int.MaxValue;
-                if (context.Console is SystemConsole systemConsole)
-                {
-                    maxWidth = systemConsole.GetWindowWidth();
-                }
-                return new HelpBuilder(context.Console, maxWidth);
-            });
+
+            _helpBuilderFactory = helpBuilderFactory;
+
             if (configureHelp != null)
             {
                 var factory = HelpBuilderFactory;
-                HelpBuilderFactory = context =>
+                _helpBuilderFactory = context =>
                 {
                     IHelpBuilder helpBuilder = factory(context);
                     configureHelp(helpBuilder);
@@ -108,6 +104,17 @@ public CommandLineConfiguration(
             }
         }
 
+        private static IHelpBuilder DefaultHelpBuilderFactory(BindingContext context)
+        {
+            int maxWidth = int.MaxValue;
+            if (context.Console is SystemConsole systemConsole)
+            {
+                maxWidth = systemConsole.GetWindowWidth();
+            }
+
+            return new HelpBuilder(context.Console, maxWidth);
+        }
+
         private void AddGlobalOptionsToChildren(Command parentCommand)
         {
             for (var childIndex = 0; childIndex < parentCommand.Children.Count; childIndex++)
@@ -151,7 +158,7 @@ private void AddGlobalOptionsToChildren(Command parentCommand)
         /// </summary>
         public Resources Resources { get; }
 
-        internal Func<BindingContext, IHelpBuilder> HelpBuilderFactory { get; }
+        internal Func<BindingContext, IHelpBuilder> HelpBuilderFactory => _helpBuilderFactory ??= DefaultHelpBuilderFactory;
 
         internal IReadOnlyCollection<InvocationMiddleware> Middleware { get; }
 
diff --git a/src/System.CommandLine/DirectiveCollection.cs b/src/System.CommandLine/DirectiveCollection.cs
@@ -10,7 +10,7 @@ namespace System.CommandLine
 {
     internal class DirectiveCollection : IDirectiveCollection
     {
-        private readonly Dictionary<string, List<string>> _directives = new Dictionary<string, List<string>>();
+        private readonly Dictionary<string, List<string>> _directives = new();
 
         public void Add(string name, string? value)
         {
diff --git a/src/System.CommandLine/Help/HelpBuilder.cs b/src/System.CommandLine/Help/HelpBuilder.cs
@@ -13,8 +13,7 @@ public class HelpBuilder : IHelpBuilder
     {
         private const string Indent = "  ";
 
-        private Dictionary<ISymbol, Customization> Customizations { get; }
-            = new Dictionary<ISymbol, Customization>();
+        private Dictionary<ISymbol, Customization> Customizations { get; } = new();
 
         protected IConsole Console { get; }
         public int MaxWidth { get; }
diff --git a/src/System.CommandLine/Help/HelpResult.cs b/src/System.CommandLine/Help/HelpResult.cs
@@ -1,7 +1,9 @@
 ﻿// Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
-namespace System.CommandLine.Invocation
+using System.CommandLine.Invocation;
+
+namespace System.CommandLine.Help
 {
     public class HelpResult : IInvocationResult
     {
diff --git a/src/System.CommandLine/IO/TestConsole.cs b/src/System.CommandLine/IO/TestConsole.cs
@@ -26,7 +26,7 @@ public TestConsole()
 
         internal class StandardStreamWriter : TextWriter, IStandardStreamWriter
         {
-            private readonly StringBuilder _stringBuilder = new StringBuilder();
+            private readonly StringBuilder _stringBuilder = new();
 
             public override void Write(char value)
             {
diff --git a/src/System.CommandLine/Parsing/ParseResultVisitor.cs b/src/System.CommandLine/Parsing/ParseResultVisitor.cs
@@ -167,7 +167,7 @@ protected override void Stop(SyntaxNode node)
             var argumentResults = new List<ArgumentResult>();
             foreach (var result in _rootCommandResult.AllArgumentResults)
             {
-                if (!(result.Parent is OptionResult))  
+                if (result.Parent is not OptionResult)  
                 {
                     argumentResults.Add(result);
                 }
@@ -300,8 +300,7 @@ private void ValidateCommandResult()
 
         private void ValidateCommandHandler()
         {
-            if (!(_innermostCommandResult!.Command is Command cmd) ||
-                cmd.Handler != null)
+            if (_innermostCommandResult!.Command is not Command { Handler: null } cmd)
             {
                 return;
             }
diff --git a/src/System.CommandLine/Parsing/SymbolResult.cs b/src/System.CommandLine/Parsing/SymbolResult.cs
@@ -10,9 +10,9 @@ namespace System.CommandLine.Parsing
     /// </summary>
     public abstract class SymbolResult
     {
-        private protected readonly List<Token> _tokens = new List<Token>();
+        private protected readonly List<Token> _tokens = new();
         private Resources? _resources;
-        private readonly Dictionary<IArgument, ArgumentResult> _defaultArgumentValues = new Dictionary<IArgument, ArgumentResult>();
+        private readonly Dictionary<IArgument, ArgumentResult> _defaultArgumentValues = new();
 
         private protected SymbolResult(
             ISymbol symbol, 
@@ -34,7 +34,7 @@ private protected SymbolResult(
         /// <summary>
         /// Child symbol results in the parse tree.
         /// </summary>
-        public SymbolResultSet Children { get; } = new SymbolResultSet();
+        public SymbolResultSet Children { get; } = new();
 
         /// <summary>
         /// The parent symbol result in the parse tree.
@@ -111,7 +111,7 @@ internal ArgumentResult GetOrCreateDefaultArgumentResult(Argument argument) =>
             _defaultArgumentValues.GetOrAdd(
                 argument,
                 arg => new ArgumentResult(
-                    argument,
+                    arg,
                     this));
 
         internal virtual bool UseDefaultValueFor(IArgument argument) => false;
diff --git a/src/System.CommandLine/Resources.cs b/src/System.CommandLine/Resources.cs
@@ -16,7 +16,7 @@ public class Resources
         /// <summary>
         /// Gets a global instance of the <see cref="Resources"/> class.
         /// </summary>
-        public static Resources Instance { get; } = new Resources();
+        public static Resources Instance { get; } = new();
 
         /// <summary>
         /// Initializes a new instance of the <see cref="Resources"/> class.
diff --git a/src/System.CommandLine/StringBuilderPool.cs b/src/System.CommandLine/StringBuilderPool.cs
@@ -24,7 +24,7 @@ internal class StringBuilderPool
         /// Gets the default instance of <see cref="StringBuilderPool"/>.
         /// </summary>
         /// <value>The default instance of <see cref="StringBuilderPool"/>.</value>
-        public static StringBuilderPool Default { get; } = new StringBuilderPool();
+        public static StringBuilderPool Default { get; } = new();
 
         /// <summary>
         /// The pool of <see cref="WeakReference{T}"/> of reusable instances of <see cref="StringBuilder"/>.
diff --git a/src/System.CommandLine/SuggestionSourceList.cs b/src/System.CommandLine/SuggestionSourceList.cs
@@ -9,7 +9,7 @@ namespace System.CommandLine
 {
     public class SuggestionSourceList : IReadOnlyList<ISuggestionSource>
     {
-        private readonly List<ISuggestionSource> _sources = new List<ISuggestionSource>();
+        private readonly List<ISuggestionSource> _sources = new();
 
         public void Add(ISuggestionSource source)
         {
diff --git a/src/System.CommandLine/Symbol.cs b/src/System.CommandLine/Symbol.cs
@@ -13,7 +13,7 @@ namespace System.CommandLine
     public abstract class Symbol : ISymbol
     {
         private string? _name;
-        private readonly SymbolSet _parents = new SymbolSet();
+        private readonly SymbolSet _parents = new();
 
         private protected Symbol()
         {
@@ -60,7 +60,7 @@ private protected void AddArgumentInner(Argument argument)
         /// <summary>
         /// Gets the child symbols.
         /// </summary>
-        public SymbolSet Children { get; } = new SymbolSet();
+        public SymbolSet Children { get; } = new();
 
         /// <summary>
         /// Gets or sets a value indicating whether the symbol is hidden.

Original file line number	Diff line number	Diff line change
`@@ -14,10 +14,10 @@ private protected ArgumentConversionResult(IArgument argument)`
`14`	`14`
`15`	`15`	`internal string? ErrorMessage { get; set; }`
`16`	`16`
`17`		`- internal static FailedArgumentConversionResult Failure(IArgument argument, string error) => new FailedArgumentConversionResult(argument, error);`
	`17`	`+ internal static FailedArgumentConversionResult Failure(IArgument argument, string error) => new(argument, error);`
`18`	`18`
`19`		`- public static SuccessfulArgumentConversionResult Success(IArgument argument, object? value) => new SuccessfulArgumentConversionResult(argument, value);`
	`19`	`+ public static SuccessfulArgumentConversionResult Success(IArgument argument, object? value) => new(argument, value);`
`20`	`20`
`21`		`- internal static NoArgumentConversionResult None(IArgument argument) => new NoArgumentConversionResult(argument);`
	`21`	`+ internal static NoArgumentConversionResult None(IArgument argument) => new(argument);`
`22`	`22`	`}`
`23`	`23`	`}`
Original file line number	Diff line number	Diff line change
`@@ -68,18 +68,18 @@ internal static bool CanBeBoundFromScalarValue(this Type type)`
`68`	`68`	`{`
`69`	`69`	`return type.GetGenericTypeDefinition() switch`
`70`	`70`	`{`
`71`		`- Type enumerable when enumerable == typeof(IEnumerable<>) => GetEmptyEnumerable(itemType),`
`72`		`- Type list when list == typeof(List<>) => GetEmptyList(itemType),`
`73`		`- Type array when array == typeof(IList<>) \|\|`
`74`		`- array == typeof(ICollection<>) => CreateEmptyArray(itemType),`
	`71`	`+ { } enumerable when enumerable == typeof(IEnumerable<>) => GetEmptyEnumerable(itemType),`
	`72`	`+ { } list when list == typeof(List<>) => GetEmptyList(itemType),`
	`73`	`+ { } array when array == typeof(IList<>) \|\|`
	`74`	`+ array == typeof(ICollection<>) => CreateEmptyArray(itemType),`
`75`	`75`	`_ => null`
`76`	`76`	`};`
`77`	`77`	`}`
`78`	`78`	`}`
`79`	`79`
`80`	`80`	`return type switch`
`81`	`81`	`{`
`82`		`- Type nonGeneric`
	`82`	`+ { } nonGeneric`
`83`	`83`	`when nonGeneric == typeof(IList) \|\|`
`84`	`84`	`nonGeneric == typeof(ICollection) \|\|`
`85`	`85`	`nonGeneric == typeof(IEnumerable)`
Original file line number	Diff line number	Diff line change
`@@ -32,6 +32,7 @@ internal object Invoke(IReadOnlyCollection<object?> parameters)`
`32`	`32`	`return _constructorInfo.Invoke(parameters.ToArray());`
`33`	`33`	`}`
`34`	`34`
	`35`	`+ /// <inheritdoc />`
`35`	`36`	`public override string ToString() =>`
`36`	`37`	`$"{Parent} ({string.Join(", ", ParameterDescriptors)})";`
`37`	`38`	`}`
Original file line number	Diff line number	Diff line change
`@@ -24,10 +24,10 @@ internal ModelBinder(IValueDescriptor valueDescriptor)`
`24`	`24`	`public bool EnforceExplicitBinding { get; set; }`
`25`	`25`
`26`	`26`	`internal Dictionary<IValueDescriptor, IValueSource> ConstructorArgumentBindingSources { get; } =`
`27`		`- new Dictionary<IValueDescriptor, IValueSource>();`
	`27`	`+ new();`
`28`	`28`
`29`	`29`	`internal Dictionary<IValueDescriptor, IValueSource> MemberBindingSources { get; } =`
`30`		`- new Dictionary<IValueDescriptor, IValueSource>();`
	`30`	`+ new();`
`31`	`31`
`32`	`32`	`// Consider deprecating in favor or BindingConfiguration/BindingContext attach validatation. Then make internal.`
`33`	`33`	`// Or at least rename to "ConfigureBinding" or similar`
`@@ -133,7 +133,7 @@ private bool ShortCutTheBinding()`
`133`	`133`	`{`
`134`	`134`	`return (false, null, false);`
`135`	`135`	`}`
`136`		`- if (!(newInstance is null))`
	`136`	`+ if (newInstance is not null)`
`137`	`137`	`{`
`138`	`138`	`nonDefaultsUsed = UpdateInstanceInternalNotifyIfNonDefaultsUsed(newInstance, bindingContext);`
`139`	`139`	`}`
`@@ -333,7 +333,7 @@ protected IValueDescriptor FindModelPropertyDescriptor(Type propertyType, string`
`333`	`333`
`334`	`334`	`private ConstructorInfo FindConstructorOrThrow(ParameterInfo parameter, string message)`
`335`	`335`	`{`
`336`		`- if (!(parameter.Member is ConstructorInfo constructor))`
	`336`	`+ if (parameter.Member is not ConstructorInfo constructor)`
`337`	`337`	`{`
`338`	`338`	`throw new ArgumentException(paramName: nameof(parameter),`
`339`	`339`	`message: message);`
Original file line number	Diff line number	Diff line change
`@@ -34,6 +34,7 @@ public void SetValue(object? instance, object? value)`
`34`	`34`	`_propertyInfo.SetValue(instance, value);`
`35`	`35`	`}`
`36`	`36`
	`37`	`+ /// <inheritdoc />`
`37`	`38`	`public override string ToString() => $"{ValueType.Name} {Path}";`
`38`	`39`	`}`
`39`	`40`	`}`
Original file line number	Diff line number	Diff line change
`@@ -23,15 +23,15 @@ public bool TryGetValue(IValueDescriptor valueDescriptor,`
`23`	`23`	`{`
`24`	`24`	`case IOption option:`
`25`	`25`	`var optionResult = bindingContext?.ParseResult.FindResultFor(option);`
`26`		`- if (!(optionResult is null))`
	`26`	`+ if (optionResult is not null)`
`27`	`27`	`{`
`28`	`28`	`boundValue = optionResult.GetValueOrDefault();`
`29`	`29`	`return true;`
`30`	`30`	`}`
`31`	`31`	`break;`
`32`	`32`	`case IArgument argument:`
`33`	`33`	`var argumentResult = bindingContext?.ParseResult.FindResultFor(argument);`
`34`		`- if (!(argumentResult is null))`
	`34`	`+ if (argumentResult is not null)`
`35`	`35`	`{`
`36`	`36`	`boundValue = argumentResult.GetValueOrDefault();`
`37`	`37`	`return true;`
Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,7 @@ namespace System.CommandLine.Builder`
`12`	`12`	`{`
`13`	`13`	`public class CommandLineBuilder : CommandBuilder`
`14`	`14`	`{`
`15`		`- private readonly List<(InvocationMiddleware middleware, int order)> _middlewareList = new List<(InvocationMiddleware middleware, int order)>();`
	`15`	`+ private readonly List<(InvocationMiddleware middleware, int order)> _middlewareList = new();`
`16`	`16`
`17`	`17`	`public CommandLineBuilder(Command? rootCommand = null)`
`18`	`18`	`: base(rootCommand ?? new RootCommand())`