Moving CancelOnProcessTermination out of middleware, better cancellation support

samples/HostingPlayground/Program.cs

@@ -12,7 +12,7 @@ namespace HostingPlayground
 {
     class Program
     {
-        static async Task Main(string[] args) => await BuildCommandLine()
+        static Task Main(string[] args) => BuildCommandLine()
             .UseHost(_ => Host.CreateDefaultBuilder(),
                 host =>
                 {

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

@@ -12,7 +12,7 @@ System.CommandLine.Hosting
     public static System.CommandLine.CommandLineBuilder UseHost(this System.CommandLine.CommandLineBuilder builder, System.Func<System.String[],Microsoft.Extensions.Hosting.IHostBuilder> hostBuilderFactory, System.Action<Microsoft.Extensions.Hosting.IHostBuilder> configureHost = null)
     public static Microsoft.Extensions.Hosting.IHostBuilder UseInvocationLifetime(this Microsoft.Extensions.Hosting.IHostBuilder host, System.CommandLine.Invocation.InvocationContext invocation, System.Action<InvocationLifetimeOptions> configureOptions = null)
   public class InvocationLifetime, Microsoft.Extensions.Hosting.IHostLifetime
-    .ctor(Microsoft.Extensions.Options.IOptions<InvocationLifetimeOptions> options, Microsoft.Extensions.Hosting.IHostEnvironment environment, Microsoft.Extensions.Hosting.IHostApplicationLifetime applicationLifetime, System.CommandLine.Invocation.InvocationContext context = null, Microsoft.Extensions.Logging.ILoggerFactory loggerFactory = null)
+    .ctor(Microsoft.Extensions.Options.IOptions<InvocationLifetimeOptions> options, Microsoft.Extensions.Hosting.IHostEnvironment environment, Microsoft.Extensions.Hosting.IHostApplicationLifetime applicationLifetime, Microsoft.Extensions.Logging.ILoggerFactory loggerFactory = null)
     public Microsoft.Extensions.Hosting.IHostApplicationLifetime ApplicationLifetime { get; }
     public Microsoft.Extensions.Hosting.IHostEnvironment Environment { get; }
     public InvocationLifetimeOptions Options { get; }

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

@@ -99,7 +99,7 @@
     public System.Void BindParameter(System.Reflection.ParameterInfo param, System.CommandLine.Argument argument)
     public System.Void BindParameter(System.Reflection.ParameterInfo param, System.CommandLine.Option option)
     public System.Int32 Invoke(System.CommandLine.Invocation.InvocationContext context)
-    public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context)
+    public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context, System.Threading.CancellationToken cancellationToken = null)
   public class ModelDescriptor
     public static ModelDescriptor FromType<T>()
     public static ModelDescriptor FromType(System.Type type)

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

@@ -116,27 +116,27 @@ System.CommandLine
   public static class Handler
     public static System.Void SetHandler(this Command command, System.Action<System.CommandLine.Invocation.InvocationContext> handle)
     public static System.Void SetHandler(this Command command, System.Action handle)
-    public static System.Void SetHandler(this Command command, System.Func<System.Threading.Tasks.Task> handle)
-    public static System.Void SetHandler(this Command command, System.Func<System.CommandLine.Invocation.InvocationContext,System.Threading.Tasks.Task> handle)
+    public static System.Void SetHandler(this Command command, System.Func<System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
+    public static System.Void SetHandler(this Command command, System.Func<System.CommandLine.Invocation.InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle)
     public static System.Void SetHandler<T>(this Command command, Action<T> handle, IValueDescriptor<T> symbol)
-    public static System.Void SetHandler<T>(this Command command, Func<T,System.Threading.Tasks.Task> handle, IValueDescriptor<T> symbol)
+    public static System.Void SetHandler<T>(this Command command, Func<T,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T> symbol)
     public static System.Void SetHandler<T1, T2>(this Command command, Action<T1,T2> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2)
-    public static System.Void SetHandler<T1, T2>(this Command command, Func<T1,T2,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2)
+    public static System.Void SetHandler<T1, T2>(this Command command, Func<T1,T2,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2)
     public static System.Void SetHandler<T1, T2, T3>(this Command command, Action<T1,T2,T3> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3)
-    public static System.Void SetHandler<T1, T2, T3>(this Command command, Func<T1,T2,T3,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3)
+    public static System.Void SetHandler<T1, T2, T3>(this Command command, Func<T1,T2,T3,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3)
     public static System.Void SetHandler<T1, T2, T3, T4>(this Command command, Action<T1,T2,T3,T4> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4)
-    public static System.Void SetHandler<T1, T2, T3, T4>(this Command command, Func<T1,T2,T3,T4,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4)
+    public static System.Void SetHandler<T1, T2, T3, T4>(this Command command, Func<T1,T2,T3,T4,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4)
     public static System.Void SetHandler<T1, T2, T3, T4, T5>(this Command command, Action<T1,T2,T3,T4,T5> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5>(this Command command, Func<T1,T2,T3,T4,T5,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5)
+    public static System.Void SetHandler<T1, T2, T3, T4, T5>(this Command command, Func<T1,T2,T3,T4,T5,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5)
     public static System.Void SetHandler<T1, T2, T3, T4, T5, T6>(this Command command, Action<T1,T2,T3,T4,T5,T6> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6>(this Command command, Func<T1,T2,T3,T4,T5,T6,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6)
+    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6>(this Command command, Func<T1,T2,T3,T4,T5,T6,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6)
     public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7>(this Command command, Action<T1,T2,T3,T4,T5,T6,T7> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7)
+    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7)
     public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(this Command command, Action<T1,T2,T3,T4,T5,T6,T7,T8> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7, IValueDescriptor<T8> symbol8)
-    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,T8,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7, IValueDescriptor<T8> symbol8)
+    public static System.Void SetHandler<T1, T2, T3, T4, T5, T6, T7, T8>(this Command command, Func<T1,T2,T3,T4,T5,T6,T7,T8,System.Threading.CancellationToken,System.Threading.Tasks.Task> handle, IValueDescriptor<T1> symbol1, IValueDescriptor<T2> symbol2, IValueDescriptor<T3> symbol3, IValueDescriptor<T4> symbol4, IValueDescriptor<T5> symbol5, IValueDescriptor<T6> symbol6, IValueDescriptor<T7> symbol7, IValueDescriptor<T8> symbol8)
   public interface ICommandHandler
     public System.Int32 Invoke(System.CommandLine.Invocation.InvocationContext context)
-    public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context)
+    public System.Threading.Tasks.Task<System.Int32> InvokeAsync(System.CommandLine.Invocation.InvocationContext context, System.Threading.CancellationToken cancellationToken = null)
   public interface IConsole : System.CommandLine.IO.IStandardError, System.CommandLine.IO.IStandardIn, System.CommandLine.IO.IStandardOut
   public abstract class IdentifierSymbol : Symbol
     public System.Collections.Generic.IReadOnlyCollection<System.String> Aliases { get; }
@@ -324,8 +324,8 @@ System.CommandLine.Help
     public System.Boolean Equals(TwoColumnHelpRow other)
     public System.Int32 GetHashCode()
 System.CommandLine.Invocation
-  public class InvocationContext, System.IDisposable
-    .ctor(System.CommandLine.ParseResult parseResult, System.CommandLine.IConsole console = null, System.Threading.CancellationToken cancellationToken = null)
+  public class InvocationContext
+    .ctor(System.CommandLine.ParseResult parseResult, System.CommandLine.IConsole console = null)
     public System.CommandLine.Binding.BindingContext BindingContext { get; }
     public System.CommandLine.IConsole Console { get; set; }
     public System.Int32 ExitCode { get; set; }
@@ -334,17 +334,15 @@ System.CommandLine.Invocation
     public System.CommandLine.LocalizationResources LocalizationResources { get; }
     public System.CommandLine.Parsing.Parser Parser { get; }
     public System.CommandLine.ParseResult ParseResult { get; set; }
-    public System.Threading.CancellationToken GetCancellationToken()
     public System.Object GetValue(System.CommandLine.Option option)
     public T GetValue<T>(Option<T> option)
     public System.Object GetValue(System.CommandLine.Argument argument)
     public T GetValue<T>(Argument<T> argument)
-    public System.Void LinkToken(System.Threading.CancellationToken token)
   public delegate InvocationMiddleware : System.MulticastDelegate, System.ICloneable, System.Runtime.Serialization.ISerializable
     .ctor(System.Object object, System.IntPtr method)
-    public System.IAsyncResult BeginInvoke(InvocationContext context, System.Func<InvocationContext,System.Threading.Tasks.Task> next, System.AsyncCallback callback, System.Object object)
+    public System.IAsyncResult BeginInvoke(InvocationContext context, System.Threading.CancellationToken cancellationToken, System.Func<InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> next, System.AsyncCallback callback, System.Object object)
     public System.Threading.Tasks.Task EndInvoke(System.IAsyncResult result)
-    public System.Threading.Tasks.Task Invoke(InvocationContext context, System.Func<InvocationContext,System.Threading.Tasks.Task> next)
+    public System.Threading.Tasks.Task Invoke(InvocationContext context, System.Threading.CancellationToken cancellationToken, System.Func<InvocationContext,System.Threading.CancellationToken,System.Threading.Tasks.Task> next)
   public enum MiddlewareOrder : System.Enum, System.IComparable, System.IConvertible, System.IFormattable
     Default=0
     ErrorReporting=1000

src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_Directives_Suggest.cs

@@ -46,8 +46,8 @@ public void Setup()
         public string TestCmdArgs;
 
         [Benchmark]
-        public async Task InvokeSuggest()
-            => await _testParser.InvokeAsync(TestCmdArgs, _nullConsole);
+        public Task InvokeSuggest()
+            => _testParser.InvokeAsync(TestCmdArgs, _nullConsole);
 
     }
 }

src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_TypoCorrection.cs

@@ -53,7 +53,7 @@ public IEnumerable<BdnParam<ParseResult>> GenerateTestParseResults()
 
         [Benchmark]
         [ArgumentsSource(nameof(GenerateTestParseResults))]
-        public async Task TypoCorrection(BdnParam<ParseResult> parseResult)
-            => await parseResult.Value.InvokeAsync(_nullConsole);
+        public Task TypoCorrection(BdnParam<ParseResult> parseResult)
+            => parseResult.Value.InvokeAsync(_nullConsole);
     }
 }

src/System.CommandLine.Benchmarks/DragonFruit/Perf_CommandLine_EntryPoint.cs

@@ -129,17 +129,17 @@ public void Setup()
         }
 
         [Benchmark(Description = "ExecuteAssemblyAsync entry point search.")]
-        public async Task SearchForStartingPointUsingReflection()
-               => await System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
+        public Task SearchForStartingPointUsingReflection()
+               => System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
                     _testAssembly,
                     new string[] { },
                     null,
                     _testAssemblyXmlDocsFilePath,
                    _nullConsole);
 
         [Benchmark(Description = "ExecuteAssemblyAsync explicit entry point.")]
-        public async Task SearchForStartingPointWhenGivenEntryPointClass()
-            => await System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
+        public Task SearchForStartingPointWhenGivenEntryPointClass()
+            => System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
                 _testAssembly,
                 new string[] { },
                 "PerfTestApp.Program",

src/System.CommandLine.Benchmarks/DragonFruit/Perf_CommandLine_Help.cs

@@ -39,8 +39,8 @@ public void Setup()
         }
 
         [Benchmark(Description = "--help")]
-        public async Task SearchForStartingPointWhenGivenEntryPointClass_Help()
-            => await System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
+        public Task SearchForStartingPointWhenGivenEntryPointClass_Help()
+            => System.CommandLine.DragonFruit.CommandLine.ExecuteAssemblyAsync(
                 _testAssembly,
                 new[] { "--help" },
                 null,

src/System.CommandLine.DragonFruit/CommandLine.cs

@@ -28,7 +28,7 @@ public static class CommandLine
         /// <param name="xmlDocsFilePath">Explicitly defined path to xml file containing XML Docs</param>
         /// <param name="console">Output console</param>
         /// <returns>The exit code.</returns>
-        public static async Task<int> ExecuteAssemblyAsync(
+        public static Task<int> ExecuteAssemblyAsync(
             Assembly entryAssembly,
             string[] args,
             string entryPointFullTypeName,
@@ -46,7 +46,7 @@ public static async Task<int> ExecuteAssemblyAsync(
             MethodInfo entryMethod = EntryPointDiscoverer.FindStaticEntryMethod(entryAssembly, entryPointFullTypeName);
 
             //TODO The xml docs file name and location can be customized using <DocumentationFile> project property.
-            return await InvokeMethodAsync(args, entryMethod, xmlDocsFilePath, null, console);
+            return InvokeMethodAsync(args, entryMethod, xmlDocsFilePath, null, console);
         }
 
         /// <summary>
@@ -79,7 +79,7 @@ public static int ExecuteAssembly(
             return InvokeMethod(args, entryMethod, xmlDocsFilePath, null, console);
         }
 
-        public static async Task<int> InvokeMethodAsync(
+        public static Task<int> InvokeMethodAsync(
             string[] args,
             MethodInfo method,
             string xmlDocsFilePath = null,
@@ -88,7 +88,7 @@ public static async Task<int> InvokeMethodAsync(
         {
             Parser parser = BuildParser(method, xmlDocsFilePath, target);
 
-            return await parser.InvokeAsync(args, console);
+            return parser.InvokeAsync(args, console);
         }
 
         public static int InvokeMethod(

src/System.CommandLine.Generator/CommandHandlerSourceGenerator.cs

@@ -115,10 +115,10 @@ private class GeneratedHandler_{handlerCount} : {ICommandHandlerType}
             }
 
             builder.Append($@"
-            public int Invoke(global::System.CommandLine.Invocation.InvocationContext context) => InvokeAsync(context).GetAwaiter().GetResult();");
+            public int Invoke(global::System.CommandLine.Invocation.InvocationContext context) => InvokeAsync(context, global::System.Threading.CancellationToken.None).GetAwaiter().GetResult();");
 
             builder.Append($@"
-            public async global::System.Threading.Tasks.Task<int> InvokeAsync(global::System.CommandLine.Invocation.InvocationContext context)
+            public async global::System.Threading.Tasks.Task<int> InvokeAsync(global::System.CommandLine.Invocation.InvocationContext context, global::System.Threading.CancellationToken cancellationToken)
             {{");
             builder.Append($@"
                 {invocation.InvokeContents()}");

src/System.CommandLine.Hosting.Tests/HostingHandlerTest.cs

@@ -1,6 +1,7 @@
 using System.CommandLine;
 using System.CommandLine.Invocation;
 using System.CommandLine.Parsing;
+using System.Threading;
 using System.Threading.Tasks;
 using FluentAssertions;
 using Microsoft.Extensions.DependencyInjection;
@@ -143,7 +144,7 @@ public int Invoke(InvocationContext context)
                 return Act();
             }
 
-            public Task<int> InvokeAsync(InvocationContext context)
+            public Task<int> InvokeAsync(InvocationContext context, CancellationToken cancellationToken)
             {
                 return Task.FromResult(Act());
             }
@@ -176,7 +177,7 @@ public int Invoke(InvocationContext context)
                     return IntOption;
                 }
 
-                public Task<int> InvokeAsync(InvocationContext context)
+                public Task<int> InvokeAsync(InvocationContext context, CancellationToken cancellationToken)
                 {
                     service.Value = IntOption;
                     return Task.FromResult(IntOption);
@@ -222,9 +223,9 @@ public MyHandler(MyService service)
 
                 public string One { get; set; }
 
-                public int Invoke(InvocationContext context) => InvokeAsync(context).GetAwaiter().GetResult();
+                public int Invoke(InvocationContext context) => InvokeAsync(context, CancellationToken.None).GetAwaiter().GetResult();
 
-                public Task<int> InvokeAsync(InvocationContext context)
+                public Task<int> InvokeAsync(InvocationContext context, CancellationToken cancellationToken)
                 {
                     service.Value = IntOption;
                     service.StringValue = One;