Add support for IPAddress and IPEndpoint arguments (#1735)

* Add support of IPAddress and IPEndpoint arguments

* IPEndPoint.TryParse isn't supported until .Net 7

* TryParse should work from .Net Core >= 3.1

* Add missing [Fact] attributes

* Remove nullable IPAddress/IPEndPoint tests

Author: RobThree

src/System.CommandLine.Tests/Binding/TypeConversionTests.cs

@@ -8,6 +8,7 @@
 using FluentAssertions;
 using System.Linq;
 using Xunit;
+using System.Net;
 
 namespace System.CommandLine.Tests.Binding
 {
@@ -708,7 +709,29 @@ public void Values_can_be_correctly_converted_to_nullable_sbyte_without_the_pars
 
             value.Should().Be(123);
         }
-        
+
+        [Fact]
+        public void Values_can_be_correctly_converted_to_ipaddress_without_the_parser_specifying_a_custom_converter()
+        {
+            var option = new Option<IPAddress>("-us");
+
+            var value = option.Parse("-us 1.2.3.4").GetValueForOption(option);
+
+            value.Should().Be(IPAddress.Parse("1.2.3.4"));
+        }
+
+#if NETCOREAPP3_0_OR_GREATER
+        [Fact]
+        public void Values_can_be_correctly_converted_to_ipendpoint_without_the_parser_specifying_a_custom_converter()
+        {
+            var option = new Option<IPEndPoint>("-us");
+
+            var value = option.Parse("-us 1.2.3.4:56").GetValueForOption(option);
+
+            value.Should().Be(IPEndPoint.Parse("1.2.3.4:56"));
+        }
+#endif
+
         [Fact]
         public void Values_can_be_correctly_converted_to_byte_without_the_parser_specifying_a_custom_converter()
         {

src/System.CommandLine/Binding/ArgumentConverter.StringConverters.cs

@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using System.IO;
+using System.Net;
 
 namespace System.CommandLine.Binding;
 
@@ -154,6 +155,32 @@ internal static partial class ArgumentConverter
             return false;
         },
 
+        [typeof(IPAddress)] = (string token, out object? value) =>
+        {
+            if (IPAddress.TryParse(token, out var ip))
+            {
+                value = ip;
+                return true;
+            }
+
+            value = default;
+            return false;
+        },
+
+#if NETCOREAPP3_0_OR_GREATER
+        [typeof(IPEndPoint)] = (string token, out object? value) =>
+        {
+            if (IPEndPoint.TryParse(token, out var ipendpoint))
+            {
+                value = ipendpoint;
+                return true;
+            }
+
+            value = default;
+            return false;
+        },
+#endif
+
         [typeof(long)] = (string token, out object? value) =>
         {
             if (long.TryParse(token, out var longValue))