ValueParsers are now inherited in subcommands

Before this commit, sub commands did not inherit the value parsers. This is frustrating because we would need to add custom value parsers for every sub command. In the general case, it is optimal that one set of value parsers are used for all argument parsing in the application.

Author: atruskie

src/CommandLineUtils/CommandLineApplication.cs

@@ -93,7 +93,7 @@ internal CommandLineApplication(CommandLineApplication parent,
             ValidationErrorHandler = DefaultValidationErrorHandler;
             SetContext(context);
             _services = new Lazy<IServiceProvider>(() => new ServiceProvider(this));
-            ValueParsers = new ValueParserProvider();
+            ValueParsers = parent?.ValueParsers ?? new ValueParserProvider();
 
             _conventionContext = CreateConventionContext();
 

test/CommandLineUtils.Tests/ValueParserProviderCustomTests.cs

@@ -1,16 +1,14 @@
 // Copyright (c) Nate McMaster.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using McMaster.Extensions.CommandLineUtils.Abstractions;
 using System;
 using System.Globalization;
-using System.Collections.Generic;
+using System.Threading.Tasks;
 using Xunit;
-using  McMaster.Extensions.CommandLineUtils.Abstractions;
 
 namespace McMaster.Extensions.CommandLineUtils.Tests
 {
-    using System.Linq;
-
     public class ValueParserProviderCustomTests
     {
 
@@ -193,6 +191,75 @@ public void CustomParsersAreAutomaticallySingleValues()
                 optionMapper.GetOptionType(typeof(double), app.ValueParsers));
         }
 
+
+        [Command()]
+        [Subcommand("subcommand", typeof(CustomParserProgramAttributesSubCommand))]
+        private class CustomParserProgramAttributes
+        {
+            [Option("-a")]
+            public DateTimeOffset MainDate { get; }
+        }
+
+        [Command()]
+        private class CustomParserProgramAttributesSubCommand
+        {
+            [Option("-b")]
+            public DateTimeOffset SubDate { get; }
+
+            public Task<int> OnExecute(CommandLineApplication app)
+            {
+                return Task.FromResult(1);
+            }
+        }
+
+        [Fact]
+        public void CustomParsersAreAvailableToSubCommands()
+        {
+            var expectedDate = new DateTimeOffset(2018, 02, 16, 21, 30, 33, 45, TimeSpan.FromHours(10));
+           
+
+            var app = new CommandLineApplication<CustomParserProgramAttributes>();
+            app.ValueParsers.AddOrReplace(new MyDateTimeOffsetParser());
+            app.Conventions.UseDefaultConventions();
+
+            var args = new[] { "-a", expectedDate.ToString("O"), "subcommand", "-b", expectedDate.AddSeconds(123456).ToString("O") };
+
+            var result = app.Execute(args);
+
+            Assert.Equal(1, result);
+            Assert.Equal(expectedDate, app.Model.MainDate);
+            Assert.Equal(expectedDate.AddSeconds(123456), ((CommandLineApplication<CustomParserProgramAttributesSubCommand>)app.Commands[0]).Model.SubDate);
+        }
+
+        [Fact]
+        public void CustomParsersAreAvailableToBuilderSubCommands()
+        {
+            var expectedDate = new DateTimeOffset(2018, 02, 16, 21, 30, 33, 45, TimeSpan.FromHours(10));
+            DateTimeOffset actualMainDate = default;
+            DateTimeOffset actualSubDate = default;
+           
+            var app = new CommandLineApplication();
+            app.ValueParsers.AddOrReplace(new MyDateTimeOffsetParser());
+
+            var mainDate = app.Option<DateTimeOffset>("-a", "The main date to parse", CommandOptionType.SingleValue);
+            app.Command("subcommand", configCmd =>
+            {
+                var subDate = configCmd.Option<DateTimeOffset>("-b", "A date for the sub command", CommandOptionType.SingleValue);
+
+                configCmd.OnExecute(() =>
+                {
+                    actualMainDate = mainDate.ParsedValue;
+                    actualSubDate = subDate.ParsedValue;
+                });
+            });
+
+            var args = new[] { "-a", expectedDate.ToString("O"), "subcommand", "-b", expectedDate.AddSeconds(123456).ToString("O") };
+            app.Execute(args);
+
+            Assert.Equal(expectedDate, actualMainDate);
+            Assert.Equal(expectedDate.AddSeconds(123456), actualSubDate);
+        }
+
         private class BadValueParser : IValueParser
         {
             public Type TargetType { get; } = null;