Improve error message for "No parameterless constructor defined for this object"

[toddlucas]

This error message will manifest if a constructor is private, but is a dependency of another class. The following exception is thrown in beta7:

System.MissingMethodException: No parameterless constructor defined for this object.

It would be great if the message would identify the type with the missing constructor. Otherwise, one must resort to binary search debugging (commenting out various DI inputs) or similar efforts.

[mafshin]

@pranavkm Why should I get this incomplete error message while using ASP.NET Core 1.0 ?

StackTrace:

icrosoft.AspNetCore.Hosting.Internal.WebHost: Information: Request finished in 64.5025ms 200 
Microsoft.AspNetCore.Server.Kestrel: Error: Connection id "0HKT7NOIT25RI": An unhandled exception was thrown by the application.

System.MissingMethodException: No parameterless constructor defined for this object.
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at System.Activator.CreateInstance(Type type)
   at Microsoft.AspNetCore.Routing.DefaultInlineConstraintResolver.CreateConstraint(Type constraintType, String argumentString)
   at Microsoft.AspNetCore.Routing.DefaultInlineConstraintResolver.ResolveConstraint(String inlineConstraint)
   at Microsoft.AspNetCore.Routing.RouteConstraintBuilder.AddResolvedConstraint(String key, String constraintText)
   at Microsoft.AspNetCore.Routing.Tree.TreeRouteBuilder.MapOutbound(IRouter handler, RouteTemplate routeTemplate, RouteValueDictionary requiredLinkValues, String routeName, Int32 order)
   at Microsoft.AspNetCore.Mvc.Internal.AttributeRoute.AddEntries(TreeRouteBuilder builder, ActionDescriptorCollection actions)
   at Microsoft.AspNetCore.Mvc.Internal.AttributeRoute.GetTreeRouter()
   at Microsoft.AspNetCore.Mvc.Internal.AttributeRoute.RouteAsync(RouteContext context)
   at Microsoft.AspNetCore.Routing.RouteCollection.<RouteAsync>d__9.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at Microsoft.AspNetCore.Hosting.Internal.RequestServicesContainerMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at Microsoft.AspNetCore.Server.IISIntegration.IISMiddleware.<Invoke>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.ConfiguredTaskAwaitable.ConfiguredTaskAwaiter.GetResult()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Frame`1.<RequestProcessingAsync>d__2.MoveNext()
Microsoft.AspNetCore.Hosting.Internal.WebHost: Information: Request finished in 347.2296ms 200 

project.json

  "dependencies": {
    "Autofac.Extensions.DependencyInjection": "4.0.0-rc3-280",
    "AutoMapper": "5.0.0",
    "log4net": "2.0.5",    
    "Microsoft.AspNetCore.Identity": "1.0.0",
    "Microsoft.AspNetCore.Identity.EntityFrameworkCore": "1.0.0",
    "Microsoft.AspNetCore.Mvc": "1.0.0",
    "Microsoft.AspNetCore.Mvc.Core": "1.0.0",
    "Microsoft.AspNetCore.Mvc.ViewFeatures": "1.0.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
    "Microsoft.Extensions.Configuration.Json": "1.0.0",
    "Microsoft.Extensions.Logging": "1.0.0",
    "Microsoft.Extensions.Logging.Console": "1.0.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Microsoft.Owin.Host.SystemWeb": "3.0.1",
    "BrockAllen.MembershipReboot": "8.4.0",
    "Autofac": "4.0.0-rc3-286",
    "BrockAllen.MembershipReboot.Ef": "8.0.0",    
  },

[pranavkm]

@mafshin I don't see DI anywhere in the stack trace here.

[mafshin]

As I said here(aspnet/Mvc#4991) the misleading
error message brought me here.
On 11 Jul 2016 21:01, "Pranav K" notifications@github.com wrote:

@mafshin https://github.com/mafshin I don't see DI anywhere in the
stack trace here.

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[mohamedmansour]

@pranavkm The error would be nice to tell me which service in the DI is causing this issue, instead of me hunting it down.

[pranavkm]

@mohamedmansour do you have a stack trace for the error? We fixed the issue in the 1.0.0-rc2 milestone, so you shouldn't see this message coming from DI anymore.