[deploy net7.0] Self-contained exe with trimming unused code throws TargetInvocationException

[viordash]

STR:

• select in visual studio 2022 17.4.1 project /command-line-api/tree/main/samples/HostingPlayground
• specify to .NET7 the target framework, and rebuild project
• publish the sample to folder target, with selected profile settings:
  • Configuration: Release | Any CPU
  • Target framework: net7.0
  • Deployment mode: Self-contained
  • Target runtime: win-x64
  • Target location: default path
  • File publish options: Produce single file, Enable ReadyToRun compilation, Trim unused code
• execute the published HostingPlayground.exe --name 'Joe'

When the "Trim unused code" checkbox is unchecked, the exception is no longer thrown.

[viordash]

sorry i forgot the exception details:
Unhandled exception: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object. at HostingPlayground.Program.Run(GreeterOptions, IHost) in C:\Users\User\source\repos\command-line-api\samples\HostingPlayground\Program.cs:line 41 at System.RuntimeMethodHandle.InvokeMethod(Object, Void**, Signature, Boolean) at System.Reflection.MethodInvoker.Invoke(Object, IntPtr*, BindingFlags) --- End of inner exception stack trace --- at System.Reflection.MethodInvoker.Invoke(Object, IntPtr*, BindingFlags) at System.Reflection.RuntimeMethodInfo.Invoke(Object, BindingFlags, Binder, Object[], CultureInfo) at System.Delegate.DynamicInvokeImpl(Object[] args) at System.CommandLine.NamingConventionBinder.ModelBindingCommandHandler.InvokeAsync(InvocationContext) in C:\Users\User\source\repos\command-line-api\src\System.CommandLine.NamingConventionBinder\ModelBindingCommandHandler.cs:line 87 at System.CommandLine.Invocation.InvocationPipeline.<>c__DisplayClass4_0.<<BuildInvocationChain>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Invocation\InvocationPipeline.cs:line 80 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass16_0.<<UseParseErrorReporting>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 532 --- End of stack trace from previous location --- at System.CommandLine.Hosting.HostingExtensions.<>c__DisplayClass1_0.<<UseHost>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine.Hosting\HostingExtensions.cs:line 49 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass11_0.<<UseHelp>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 424 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass21_0.<<UseVersionOption>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 661 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass18_0.<<UseTypoCorrections>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 593 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c.<<UseSuggestDirective>b__17_0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 567 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass15_0.<<UseParseDirective>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 507 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c.<<RegisterWithDotnetSuggest>b__4_0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 238 --- End of stack trace from previous location --- at System.CommandLine.CommandLineBuilderExtensions.<>c__DisplayClass7_0.<<UseExceptionHandler>b__0>d.MoveNext() in C:\Users\User\source\repos\command-line-api\src\System.CommandLine\Builder\CommandLineBuilderExtensions.cs:line 328

[elgonzo]

Trimming is currently not possible -at least not with default trim settings- with the System.CommandLine NamingConventionBinder package, as per comment from System.CommandLine author and maintainer here: #1750 (comment).

You might try configuring the trimming in such a way that it accounts for the types and members accessed through reflection by the NamingConventionBinder (https://learn.microsoft.com/en-us/dotnet/core/deploying/trimming/trimming-options?pivots=dotnet-7-0#root-descriptors),

[viordash]

Thanks for your explanation!