Implemented AddAsyncDelegate (#766)

examples/Cli/Delegates/BarSettings.cs

@@ -9,7 +9,7 @@ public static partial class Program
     {
         [CommandOption("--count")]
         [Description("The number of bars to print")]
-        [DefaultValue(1)]
+        [DefaultValue(3)]
         public int Count { get; set; }
     }
 }

examples/Cli/Delegates/Program.cs

@@ -1,3 +1,4 @@
+using System.Threading.Tasks;
 using Spectre.Console;
 using Spectre.Console.Cli;
 
@@ -14,7 +15,13 @@ public static partial class Program
                 .WithDescription("Foos the bars");
 
             config.AddDelegate<BarSettings>("bar", Bar)
-                .WithDescription("Bars the foos"); ;
+                .WithDescription("Bars the foos");
+
+            config.AddAsyncDelegate("fooAsync", FooAsync)
+                .WithDescription("Foos the bars asynchronously");
+
+            config.AddAsyncDelegate<BarSettings>("barAsync", BarAsync)
+                .WithDescription("Bars the foos asynchronously");
         });
 
         return app.Run(args);
@@ -35,4 +42,20 @@ public static partial class Program
 
         return 0;
     }
+
+    private static Task<int> FooAsync(CommandContext context)
+    {
+        AnsiConsole.WriteLine("Foo");
+        return Task.FromResult(0);
+    }
+
+    private static Task<int> BarAsync(CommandContext context, BarSettings settings)
+    {
+        for (var index = 0; index < settings.Count; index++)
+        {
+            AnsiConsole.WriteLine("Bar");
+        }
+
+        return Task.FromResult(0);
+    }
 }

examples/Console/Json/Json.csproj

@@ -9,8 +9,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\..\Shared\Shared.csproj" />
     <ProjectReference Include="..\..\..\src\Spectre.Console.Json\Spectre.Console.Json.csproj" />
+    <ProjectReference Include="..\..\Shared\Shared.csproj" />
   </ItemGroup>
 
 </Project>

examples/Examples.sln

@@ -81,6 +81,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Layout", "Console\Layout\La
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Json", "Console\Json\Json.csproj", "{ABE3E734-0756-4D5A-B28A-E6E526D9927D}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Spectre.Console.Json", "..\src\Spectre.Console.Json\Spectre.Console.Json.csproj", "{91A5637F-1F89-48B3-A0BA-6CC629807393}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -535,6 +537,18 @@ Global
 		{ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x64.Build.0 = Release|Any CPU
 		{ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x86.ActiveCfg = Release|Any CPU
 		{ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x86.Build.0 = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|x64.Build.0 = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Debug|x86.Build.0 = Debug|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|Any CPU.Build.0 = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|x64.ActiveCfg = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|x64.Build.0 = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|x86.ActiveCfg = Release|Any CPU
+		{91A5637F-1F89-48B3-A0BA-6CC629807393}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -549,6 +563,7 @@ Global
 		{0C58FB17-F60A-47AB-84BF-961EC8C06AE6} = {2571F1BD-6556-4F96-B27B-B6190E1BF13A}
 		{A127CE7D-A5A7-4745-9809-EBD7CB12CEE7} = {2571F1BD-6556-4F96-B27B-B6190E1BF13A}
 		{EFAADF6A-C77D-41EC-83F5-BBB4FFC5A6D7} = {2571F1BD-6556-4F96-B27B-B6190E1BF13A}
+		{91A5637F-1F89-48B3-A0BA-6CC629807393} = {2571F1BD-6556-4F96-B27B-B6190E1BF13A}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {3EE724C5-CAB4-410D-AC63-8D4260EF83ED}

src/Spectre.Console.Cli/ConfiguratorExtensions.cs

@@ -237,6 +237,26 @@ public static class ConfiguratorExtensions
         return configurator.AddDelegate<EmptyCommandSettings>(name, (c, _) => func(c));
     }
 
+    /// <summary>
+    /// Adds a command without settings that executes an async delegate.
+    /// </summary>
+    /// <param name="configurator">The configurator.</param>
+    /// <param name="name">The name of the command.</param>
+    /// <param name="func">The delegate to execute as part of command execution.</param>
+    /// <returns>A command configurator that can be used to configure the command further.</returns>
+    public static ICommandConfigurator AddAsyncDelegate(
+        this IConfigurator configurator,
+        string name,
+        Func<CommandContext, Task<int>> func)
+    {
+        if (configurator == null)
+        {
+            throw new ArgumentNullException(nameof(configurator));
+        }
+
+        return configurator.AddAsyncDelegate<EmptyCommandSettings>(name, (c, _) => func(c));
+    }
+
     /// <summary>
     /// Adds a command without settings that executes a delegate.
     /// </summary>
@@ -259,6 +279,28 @@ public static class ConfiguratorExtensions
         return configurator.AddDelegate<TSettings>(name, (c, _) => func(c));
     }
 
+    /// <summary>
+    /// Adds a command without settings that executes an async delegate.
+    /// </summary>
+    /// <typeparam name="TSettings">The command setting type.</typeparam>
+    /// <param name="configurator">The configurator.</param>
+    /// <param name="name">The name of the command.</param>
+    /// <param name="func">The delegate to execute as part of command execution.</param>
+    /// <returns>A command configurator that can be used to configure the command further.</returns>
+    public static ICommandConfigurator AddAsyncDelegate<TSettings>(
+        this IConfigurator<TSettings> configurator,
+        string name,
+        Func<CommandContext, Task<int>> func)
+        where TSettings : CommandSettings
+    {
+        if (configurator == null)
+        {
+            throw new ArgumentNullException(nameof(configurator));
+        }
+
+        return configurator.AddAsyncDelegate<TSettings>(name, (c, _) => func(c));
+    }
+
     /// <summary>
     /// Sets the ExceptionsHandler.
     /// <para>Setting <see cref="ICommandAppSettings.ExceptionHandler"/> this way will use the

src/Spectre.Console.Cli/IConfigurator.cs

@@ -35,6 +35,16 @@ public interface IConfigurator
     ICommandConfigurator AddDelegate<TSettings>(string name, Func<CommandContext, TSettings, int> func)
         where TSettings : CommandSettings;
 
+    /// <summary>
+    /// Adds a command that executes an async delegate.
+    /// </summary>
+    /// <typeparam name="TSettings">The command setting type.</typeparam>
+    /// <param name="name">The name of the command.</param>
+    /// <param name="func">The delegate to execute as part of command execution.</param>
+    /// <returns>A command configurator that can be used to configure the command further.</returns>
+    ICommandConfigurator AddAsyncDelegate<TSettings>(string name, Func<CommandContext, TSettings, Task<int>> func)
+        where TSettings : CommandSettings;
+
     /// <summary>
     /// Adds a command branch.
     /// </summary>

src/Spectre.Console.Cli/IConfiguratorOfT.cs

@@ -57,6 +57,16 @@ public interface IConfigurator<in TSettings>
     ICommandConfigurator AddDelegate<TDerivedSettings>(string name, Func<CommandContext, TDerivedSettings, int> func)
         where TDerivedSettings : TSettings;
 
+    /// <summary>
+    /// Adds a command that executes an async delegate.
+    /// </summary>
+    /// <typeparam name="TDerivedSettings">The derived command setting type.</typeparam>
+    /// <param name="name">The name of the command.</param>
+    /// <param name="func">The delegate to execute as part of command execution.</param>
+    /// <returns>A command configurator that can be used to configure the command further.</returns>
+    ICommandConfigurator AddAsyncDelegate<TDerivedSettings>(string name, Func<CommandContext, TDerivedSettings, Task<int>> func)
+        where TDerivedSettings : TSettings;
+
     /// <summary>
     /// Adds a command branch.
     /// </summary>

src/Spectre.Console.Cli/Internal/Configuration/Configurator.cs

@@ -42,6 +42,14 @@ internal sealed class Configurator : IUnsafeConfigurator, IConfigurator, IConfig
 
     public ICommandConfigurator AddDelegate<TSettings>(string name, Func<CommandContext, TSettings, int> func)
         where TSettings : CommandSettings
+    {
+        var command = Commands.AddAndReturn(ConfiguredCommand.FromDelegate<TSettings>(
+            name, (context, settings) => Task.FromResult(func(context, (TSettings)settings))));
+        return new CommandConfigurator(command);
+    }
+
+    public ICommandConfigurator AddAsyncDelegate<TSettings>(string name, Func<CommandContext, TSettings, Task<int>> func)
+        where TSettings : CommandSettings
     {
         var command = Commands.AddAndReturn(ConfiguredCommand.FromDelegate<TSettings>(
             name, (context, settings) => func(context, (TSettings)settings)));

src/Spectre.Console.Cli/Internal/Configuration/ConfiguratorOfT.cs

@@ -27,6 +27,7 @@ internal sealed class Configurator<TSettings> : IUnsafeBranchConfigurator, IConf
     {
         var defaultCommand = ConfiguredCommand.FromType<TDefaultCommand>(
             CliConstants.DefaultCommandName, isDefaultCommand: true);
+
         _command.Children.Add(defaultCommand);
     }
 
@@ -47,6 +48,16 @@ internal sealed class Configurator<TSettings> : IUnsafeBranchConfigurator, IConf
 
     public ICommandConfigurator AddDelegate<TDerivedSettings>(string name, Func<CommandContext, TDerivedSettings, int> func)
         where TDerivedSettings : TSettings
+    {
+        var command = ConfiguredCommand.FromDelegate<TDerivedSettings>(
+            name, (context, settings) => Task.FromResult(func(context, (TDerivedSettings)settings)));
+
+        _command.Children.Add(command);
+        return new CommandConfigurator(command);
+    }
+
+    public ICommandConfigurator AddAsyncDelegate<TDerivedSettings>(string name, Func<CommandContext, TDerivedSettings, Task<int>> func)
+        where TDerivedSettings : TSettings
     {
         var command = ConfiguredCommand.FromDelegate<TDerivedSettings>(
             name, (context, settings) => func(context, (TDerivedSettings)settings));

src/Spectre.Console.Cli/Internal/Configuration/ConfiguredCommand.cs

@@ -8,7 +8,7 @@ internal sealed class ConfiguredCommand
     public object? Data { get; set; }
     public Type? CommandType { get; }
     public Type SettingsType { get; }
-    public Func<CommandContext, CommandSettings, int>? Delegate { get; }
+    public Func<CommandContext, CommandSettings, Task<int>>? Delegate { get; }
     public bool IsDefaultCommand { get; }
     public bool IsHidden { get; set; }
 
@@ -19,7 +19,7 @@ internal sealed class ConfiguredCommand
         string name,
         Type? commandType,
         Type settingsType,
-        Func<CommandContext, CommandSettings, int>? @delegate,
+        Func<CommandContext, CommandSettings, Task<int>>? @delegate,
         bool isDefaultCommand)
     {
         Name = name;
@@ -60,7 +60,7 @@ internal sealed class ConfiguredCommand
     }
 
     public static ConfiguredCommand FromDelegate<TSettings>(
-        string name, Func<CommandContext, CommandSettings, int>? @delegate = null)
+        string name, Func<CommandContext, CommandSettings, Task<int>>? @delegate = null)
         where TSettings : CommandSettings
     {
         return new ConfiguredCommand(name, null, typeof(TSettings), @delegate, false);

src/Spectre.Console.Cli/Internal/DelegateCommand.cs

@@ -2,16 +2,16 @@ namespace Spectre.Console.Cli;
 
 internal sealed class DelegateCommand : ICommand
 {
-    private readonly Func<CommandContext, CommandSettings, int> _func;
+    private readonly Func<CommandContext, CommandSettings, Task<int>> _func;
 
-    public DelegateCommand(Func<CommandContext, CommandSettings, int> func)
+    public DelegateCommand(Func<CommandContext, CommandSettings, Task<int>> func)
     {
         _func = func;
     }
 
     public Task<int> Execute(CommandContext context, CommandSettings settings)
     {
-        return Task.FromResult(_func(context, settings));
+        return _func(context, settings);
     }
 
     public ValidationResult Validate(CommandContext context, CommandSettings settings)

src/Spectre.Console.Cli/Internal/Modelling/CommandInfo.cs

@@ -8,7 +8,7 @@ internal sealed class CommandInfo : ICommandContainer
     public object? Data { get; }
     public Type? CommandType { get; }
     public Type SettingsType { get; }
-    public Func<CommandContext, CommandSettings, int>? Delegate { get; }
+    public Func<CommandContext, CommandSettings, Task<int>>? Delegate { get; }
     public bool IsDefaultCommand { get; }
     public CommandInfo? Parent { get; }
     public IList<CommandInfo> Children { get; }

test/Spectre.Console.Cli.Tests/Unit/CommandAppTests.cs

@@ -1135,6 +1135,37 @@ public sealed partial class CommandAppTests
             data.ShouldBe(2);
         }
 
+        [Fact]
+        public async void Should_Execute_Async_Delegate_Command_At_Root_Level()
+        {
+            // Given
+            var dog = default(DogSettings);
+            var data = 0;
+
+            var app = new CommandApp();
+            app.Configure(config =>
+            {
+                config.PropagateExceptions();
+                config.AddAsyncDelegate<DogSettings>(
+                    "foo", (context, settings) =>
+                    {
+                        dog = settings;
+                        data = (int)context.Data;
+                        return Task.FromResult(1);
+                    }).WithData(2);
+            });
+
+            // When
+            var result = await app.RunAsync(new[] { "foo", "4", "12" });
+
+            // Then
+            result.ShouldBe(1);
+            dog.ShouldNotBeNull();
+            dog.Age.ShouldBe(12);
+            dog.Legs.ShouldBe(4);
+            data.ShouldBe(2);
+        }
+
         [Fact]
         public void Should_Execute_Nested_Delegate_Command()
         {
@@ -1168,5 +1199,39 @@ public sealed partial class CommandAppTests
             dog.Legs.ShouldBe(4);
             data.ShouldBe(2);
         }
+
+        [Fact]
+        public async void Should_Execute_Nested_Async_Delegate_Command()
+        {
+            // Given
+            var dog = default(DogSettings);
+            var data = 0;
+
+            var app = new CommandApp();
+            app.Configure(config =>
+            {
+                config.PropagateExceptions();
+                config.AddBranch<AnimalSettings>("foo", foo =>
+                {
+                    foo.AddAsyncDelegate<DogSettings>(
+                        "bar", (context, settings) =>
+                        {
+                            dog = settings;
+                            data = (int)context.Data;
+                            return Task.FromResult(1);
+                        }).WithData(2);
+                });
+            });
+
+            // When
+            var result = await app.RunAsync(new[] { "foo", "4", "bar", "12" });
+
+            // Then
+            result.ShouldBe(1);
+            dog.ShouldNotBeNull();
+            dog.Age.ShouldBe(12);
+            dog.Legs.ShouldBe(4);
+            data.ShouldBe(2);
+        }
     }
 }