Add [Option(DefaultValue=)]

Author: neuecc

ConsoleAppFramework.sln

@@ -39,6 +39,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		ReadMe.md = ReadMe.md
 	EndProjectSection
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ConsoleAppFramework.Template", "src\ConsoleAppFramework.Template\ConsoleAppFramework.Template.csproj", "{A76D1521-AB66-4B00-8C7B-069052EFB212}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -77,6 +79,10 @@ Global
 		{6A39E146-8CDF-4B04-88ED-395C56A32722}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{6A39E146-8CDF-4B04-88ED-395C56A32722}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{6A39E146-8CDF-4B04-88ED-395C56A32722}.Release|Any CPU.Build.0 = Release|Any CPU
+		{A76D1521-AB66-4B00-8C7B-069052EFB212}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{A76D1521-AB66-4B00-8C7B-069052EFB212}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{A76D1521-AB66-4B00-8C7B-069052EFB212}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{A76D1521-AB66-4B00-8C7B-069052EFB212}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -90,6 +96,7 @@ Global
 		{9AC1CAE2-E717-472A-BBFB-0FE5590E5C7A} = {1F399F98-7439-4F05-847B-CC1267B4B7F2}
 		{2B7CDEFC-3D92-4B72-8898-2494D7B087AD} = {A2CF2984-E8E2-48FC-B5A1-58D74A2467E6}
 		{6A39E146-8CDF-4B04-88ED-395C56A32722} = {AAD2D900-C305-4449-A9FC-6C7696FFEDFA}
+		{A76D1521-AB66-4B00-8C7B-069052EFB212} = {1F399F98-7439-4F05-847B-CC1267B4B7F2}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {7F3E353A-C125-4020-8481-11DC6496358C}

sandbox/MultiContainedApp/Program.cs

@@ -16,6 +16,7 @@ static async Task Main(string[] args)
             //args = new string[] { "foo", "echo", "help"};
             //args = new string[] { "bar.hello2", "help" };
 
+
             await Host.CreateDefaultBuilder()
                 .ConfigureLogging(x => x.SetMinimumLevel(LogLevel.Trace))
                 .RunConsoleAppFrameworkAsync(args, options: new ConsoleAppOptions

sandbox/SingleContainedApp/Program.cs

@@ -222,6 +222,7 @@ public class Program : ConsoleAppBase
         static async Task Main(string[] args)
         {
             //args = new[] { "-m", "a ", "-b", "False" };
+            args = new[] { "help" };
 
             await Host.CreateDefaultBuilder().RunConsoleAppFrameworkAsync<Program>(args, new ConsoleAppOptions
             {
@@ -231,9 +232,12 @@ static async Task Main(string[] args)
 
         }
 
-        public void Hello([Option(null, "Message to display.")]string message, bool b)
+        public void Hello(
+            int? foo = null,
+            [Option("", "", DefaultValue = "DateTime.Today")]DateTime? hello = null)
         {
-            Console.WriteLine(message + b);
+            if (hello == null) hello = DateTime.Now;
+            Console.WriteLine(hello);
         }
     }
 }

src/ConsoleAppFramework.Template/ConsoleAppFramework.Template.csproj

@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>

src/ConsoleAppFramework.Template/Program.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace ConsoleAppFramework.Template
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("Hello World!");
+        }
+    }
+}

src/ConsoleAppFramework/.template.config/template.json

@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Text;
+
+[assembly:InternalsVisibleTo("ConsoleAppFramework.Tests, PublicKey="+
+                             "002400000480000094000000060200000024000052534131000400000100010089b12412c27f5f"+
+                             "aece3868b659bf311f2550c5cc1b4cbbe032a048ec36fa288872d51e8ddfd77a83e835c6ea3940"+
+                             "c331fe89d1ba9146a12abed588f194cd437cfe81252634d49214acf6b11dc9e97cfc6d0f818082"+
+                             "e5bbafb50e890eed19517c199213075b294d5fa59556cd42186041a1a95f8cff3869575bed4de2"+
+                             "dd8f5dc2")]

src/ConsoleAppFramework/CommandHelpBuilder.cs

@@ -214,7 +214,7 @@ public string BuildOptionsMessage(CommandHelpDefinition definition)
                 sb.Append(opt.Description);
 
                 if (opt.IsFlag)
-				{
+                {
                     sb.Append($" (Optional)");
                 }
                 else if (opt.DefaultValue != null)
@@ -328,23 +328,36 @@ public CommandHelpDefinition CreateCommandHelpDefinition(MethodInfo method)
                 var defaultValue = default(string);
                 if (item.HasDefaultValue)
                 {
-                    defaultValue = (item.DefaultValue?.ToString() ?? "null");
+                    if (option?.DefaultValue != null)
+                    {
+                        defaultValue = option.DefaultValue;
+                    }
+                    else
+                    {
+                        defaultValue = (item.DefaultValue?.ToString() ?? "null");
+                    }
                     if (isFlag)
-					{
+                    {
                         if (item.DefaultValue is true)
                         {
                             // bool option with true default value is not flag.
                             isFlag = false;
                         }
-						else if(item.DefaultValue is false)
-						{
+                        else if (item.DefaultValue is false)
+                        {
                             // false default value should be omitted for flag.
                             defaultValue = null;
-						}
+                        }
                     }
                 }
 
-                parameterDefinitions.Add(new CommandOptionHelpDefinition(options.Distinct().ToArray(), description, item.ParameterType.Name, defaultValue, index, isFlag));
+                var paramTypeName = item.ParameterType.Name;
+                if (item.ParameterType.IsGenericType && item.ParameterType.GetGenericTypeDefinition() == typeof(Nullable<>))
+                {
+                    paramTypeName = item.ParameterType.GetGenericArguments()[0].Name + "?";
+                }
+
+                parameterDefinitions.Add(new CommandOptionHelpDefinition(options.Distinct().ToArray(), description, paramTypeName, defaultValue, index, isFlag));
             }
 
             return new CommandHelpDefinition(

src/ConsoleAppFramework/OptionAttribute.cs

@@ -9,6 +9,9 @@ public class OptionAttribute : Attribute
         public string? ShortName { get; }
         public string? Description { get; }
 
+        /// <summary>Override default value on help.</summary>
+        public string? DefaultValue { get; set; }
+
         public OptionAttribute(int index)
         {
             this.Index = index;