Move non-generic extensions to be instance methods

src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt

@@ -5,9 +5,17 @@ System.CommandLine
     public System.Boolean HasDefaultValue { get; }
     public System.String HelpName { get; set; }
     public System.Type ValueType { get; }
+    public Argument AcceptOnlyFromAmong(System.String[] values)
+    public Argument AddCompletions(System.String[] values)
+    public Argument AddCompletions(System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> complete)
+    public Argument AddCompletions(System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>> complete)
     public System.Void AddValidator(System.Action<System.CommandLine.Parsing.ArgumentResult> validate)
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
     public System.Object GetDefaultValue()
+    public Argument LegalFileNamesOnly()
+    public Argument LegalFilePathsOnly()
+    public ParseResult Parse(System.String commandLine)
+    public ParseResult Parse(System.String[] args)
     public System.Void SetDefaultValue(System.Object value)
     public System.Void SetDefaultValueFactory(System.Func<System.Object> defaultValueFactory)
     public System.Void SetDefaultValueFactory(System.Func<System.CommandLine.Parsing.ArgumentResult,System.Object> defaultValueFactory)
@@ -32,19 +40,11 @@ System.CommandLine
     public System.Boolean Equals(ArgumentArity other)
     public System.Boolean Equals(System.Object obj)
     public System.Int32 GetHashCode()
-  public static class ArgumentExtensions
+  public static class ArgumentValidationExtensions
     public static Argument<System.IO.FileInfo> AcceptExistingOnly(this Argument<System.IO.FileInfo> argument)
     public static Argument<System.IO.DirectoryInfo> AcceptExistingOnly(this Argument<System.IO.DirectoryInfo> argument)
     public static Argument<System.IO.FileSystemInfo> AcceptExistingOnly(this Argument<System.IO.FileSystemInfo> argument)
     public static Argument<T> AcceptExistingOnly<T>(this Argument<T> argument)
-    public static TArgument AcceptOnlyFromAmong<TArgument>(this TArgument argument, System.String[] values)
-    public static TArgument AddCompletions<TArgument>(this TArgument argument, System.String[] values)
-    public static TArgument AddCompletions<TArgument>(this TArgument argument, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> complete)
-    public static TArgument AddCompletions<TArgument>(this TArgument argument, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>> complete)
-    public static TArgument LegalFileNamesOnly<TArgument>(this TArgument argument)
-    public static TArgument LegalFilePathsOnly<TArgument>(this TArgument argument)
-    public static ParseResult Parse(this Argument argument, System.String commandLine)
-    public static ParseResult Parse(this Argument argument, System.String[] args)
   public class Command : IdentifierSymbol, System.Collections.Generic.IEnumerable<Symbol>, System.Collections.IEnumerable, System.CommandLine.Completions.ICompletionSource
     .ctor(System.String name, System.String description = null)
     public System.Collections.Generic.IReadOnlyList<Argument> Arguments { get; }
@@ -194,9 +194,17 @@ System.CommandLine
     public ArgumentArity Arity { get; set; }
     public System.Boolean IsRequired { get; set; }
     public System.Type ValueType { get; }
+    public Option AcceptOnlyFromAmong(System.String[] values)
+    public Option AddCompletions(System.String[] values)
+    public Option AddCompletions(System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> complete)
+    public Option AddCompletions(System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>> complete)
     public System.Void AddValidator(System.Action<System.CommandLine.Parsing.OptionResult> validate)
     public System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem> GetCompletions(System.CommandLine.Completions.CompletionContext context)
     public System.Boolean HasAliasIgnoringPrefix(System.String alias)
+    public Option LegalFileNamesOnly()
+    public Option LegalFilePathsOnly()
+    public ParseResult Parse(System.String commandLine)
+    public ParseResult Parse(System.String[] args)
     public System.Void SetDefaultValue(System.Object value)
     public System.Void SetDefaultValueFactory(System.Func<System.Object> defaultValueFactory)
   public class Option<T> : Option, IValueDescriptor<T>, System.CommandLine.Binding.IValueDescriptor, System.CommandLine.Completions.ICompletionSource
@@ -207,19 +215,11 @@ System.CommandLine
     .ctor(System.String name, Func<T> defaultValueFactory, System.String description = null)
     .ctor(System.String[] aliases, Func<T> defaultValueFactory, System.String description = null)
     public ArgumentArity Arity { get; set; }
-  public static class OptionExtensions
+  public static class OptionValidationExtensions
     public static Option<System.IO.FileInfo> AcceptExistingOnly(this Option<System.IO.FileInfo> option)
     public static Option<System.IO.DirectoryInfo> AcceptExistingOnly(this Option<System.IO.DirectoryInfo> option)
     public static Option<System.IO.FileSystemInfo> AcceptExistingOnly(this Option<System.IO.FileSystemInfo> option)
     public static Option<T> AcceptExistingOnly<T>(this Option<T> option)
-    public static TOption AcceptOnlyFromAmong<TOption>(this TOption option, System.String[] values)
-    public static TOption AddCompletions<TOption>(this TOption option, System.String[] values)
-    public static TOption AddCompletions<TOption>(this TOption option, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.String>> complete)
-    public static TOption AddCompletions<TOption>(this TOption option, System.Func<System.CommandLine.Completions.CompletionContext,System.Collections.Generic.IEnumerable<System.CommandLine.Completions.CompletionItem>> complete)
-    public static TOption LegalFileNamesOnly<TOption>(this TOption option)
-    public static TOption LegalFilePathsOnly<TOption>(this TOption option)
-    public static ParseResult Parse(this Option option, System.String commandLine)
-    public static ParseResult Parse(this Option option, System.String[] args)
   public class ParseResult
     public System.CommandLine.Parsing.CommandResult CommandResult { get; }
     public System.Collections.Generic.IReadOnlyDictionary<System.String,System.Collections.Generic.IReadOnlyList<System.String>> Directives { get; }

src/System.CommandLine.Suggest/SuggestionDispatcher.cs

@@ -89,9 +89,15 @@ public SuggestionDispatcher(ISuggestionRegistration suggestionRegistration, ISug
 
         private Command GetCommand { get; }
 
-        private Option<FileInfo> ExecutableOption { get; } =
-            new Option<FileInfo>(new[] { "-e", "--executable" }, "The executable to call for suggestions")
-                .LegalFilePathsOnly();
+        private Option<FileInfo> ExecutableOption { get; } = GetExecutableOption();
+
+        private static Option<FileInfo> GetExecutableOption()
+        {
+            var option = new Option<FileInfo>(new[] { "-e", "--executable" }, "The executable to call for suggestions");
+            option.LegalFilePathsOnly();
+
+            return option;
+        }
 
         private Command ListCommand { get; }
 

src/System.CommandLine/Argument.cs

@@ -6,6 +6,7 @@
 using System.CommandLine.Parsing;
 using System.CommandLine.Completions;
 using System.Linq;
+using System.IO;
 
 namespace System.CommandLine
 {
@@ -202,5 +203,124 @@ public override IEnumerable<CompletionItem> GetCompletions(CompletionContext con
 
         /// <inheritdoc />
         string IValueDescriptor.ValueName => Name;
+
+        /// <summary>
+        /// Adds completions for the argument.
+        /// </summary>
+        /// <param name="values">The completions to add.</param>
+        /// <returns>The configured argument.</returns>
+        public Argument AddCompletions(params string[] values)
+        {
+            Completions.Add(values);
+            return this;
+        }
+
+        /// <summary>
+        /// Adds completions for the argument.
+        /// </summary>
+        /// <param name="complete">A function that will be called to provide completions.</param>
+        /// <returns>The option being extended.</returns>
+        public Argument AddCompletions(Func<CompletionContext, IEnumerable<string>> complete)
+        {
+            Completions.Add(complete);
+            return this;
+        }
+
+        /// <summary>
+        /// Adds completions for the argument.
+        /// </summary>
+        /// <param name="complete">A function that will be called to provide completions.</param>
+        /// <returns>The configured argument.</returns>
+        public Argument AddCompletions(Func<CompletionContext, IEnumerable<CompletionItem>> complete)
+        {
+            Completions.Add(complete);
+            return this;
+        }
+
+        /// <summary>
+        /// Configures the argument to accept only the specified values, and to suggest them as command line completions.
+        /// </summary>
+        /// <param name="values">The values that are allowed for the argument.</param>
+        /// <returns>The configured argument.</returns>
+        public Argument AcceptOnlyFromAmong(params string[] values)
+        {
+            AllowedValues?.Clear();
+            AddAllowedValues(values);
+            Completions.Clear();
+            Completions.Add(values);
+
+            return this;
+        }
+
+        /// <summary>
+        /// Configures the argument to accept only values representing legal file paths.
+        /// </summary>
+        /// <returns>The configured argument.</returns>
+        public Argument LegalFilePathsOnly()
+        {
+            var invalidPathChars = Path.GetInvalidPathChars();
+
+            AddValidator(result =>
+            {
+                for (var i = 0; i < result.Tokens.Count; i++)
+                {
+                    var token = result.Tokens[i];
+
+                    // File class no longer check invalid character
+                    // https://blogs.msdn.microsoft.com/jeremykuhne/2018/03/09/custom-directory-enumeration-in-net-core-2-1/
+                    var invalidCharactersIndex = token.Value.IndexOfAny(invalidPathChars);
+
+                    if (invalidCharactersIndex >= 0)
+                    {
+                        result.ErrorMessage = result.LocalizationResources.InvalidCharactersInPath(token.Value[invalidCharactersIndex]);
+                    }
+                }
+            });
+
+            return this;
+        }
+
+        /// <summary>
+        /// Configures the argument to accept only values representing legal file names.
+        /// </summary>
+        /// <remarks>A parse error will result, for example, if file path separators are found in the parsed value.</remarks>
+        /// <returns>The configured argument.</returns>
+        public Argument LegalFileNamesOnly()
+        {
+            var invalidFileNameChars = Path.GetInvalidFileNameChars();
+
+            AddValidator(result =>
+            {
+                for (var i = 0; i < result.Tokens.Count; i++)
+                {
+                    var token = result.Tokens[i];
+                    var invalidCharactersIndex = token.Value.IndexOfAny(invalidFileNameChars);
+
+                    if (invalidCharactersIndex >= 0)
+                    {
+                        result.ErrorMessage = result.LocalizationResources.InvalidCharactersInFileName(token.Value[invalidCharactersIndex]);
+                    }
+                }
+            });
+
+            return this;
+        }
+
+        /// <summary>
+        /// Parses a command line string value using the argument.
+        /// </summary>
+        /// <remarks>The command line string input will be split into tokens as if it had been passed on the command line.</remarks>
+        /// <param name="commandLine">A command line string to parse, which can include spaces and quotes equivalent to what can be entered into a terminal.</param>
+        /// <returns>A parse result describing the outcome of the parse operation.</returns>
+        public ParseResult Parse(string commandLine) =>
+            this.GetOrCreateDefaultSimpleParser().Parse(commandLine);
+
+        /// <summary>
+        /// Parses a command line string value using the argument.
+        /// </summary>
+        /// <param name="args">The string arguments to parse.</param>
+        /// <returns>A parse result describing the outcome of the parse operation.</returns>
+        public ParseResult Parse(string[] args) =>
+            this.GetOrCreateDefaultSimpleParser().Parse(args);
     }
 }