ActivatorUtilitiesConstructorAttribute Does Not Work in Some Cases

[lawrence-laz]

Describe the bug

ActivatorUtilities.CreateInstance<T>(IServiceProvider provider, params object[] parameters) does not respect ActivatorUtilitiesConstructorAttribute in a case when constructor ordering is changed.

To Reproduce

Steps to reproduce the behavior:

1. Using version '3.1.6' of package 'Microsoft.Extensions.DependencyInjection'
2. Run this test code:

   using Microsoft.Extensions.DependencyInjection;
   using System;
   using Xunit;
   
   namespace UnitTests
   {
       public class ActivatorUtilitiesConstructorTests
       {
           public class Dependency1 { }
           public class Dependency2 { }
           public class Dependency3 { }
   
           public class Service1
           {
               public Service1(Dependency1 dependency1, Dependency3 dependency3)
               {
                   throw new Exception("This should not be called.");
               }
   
               [ActivatorUtilitiesConstructor]
               public Service1(Dependency1 dependency1, Dependency2 dependency2, Dependency3 dependency3)
               {
               }
           }
   
           public class Service2
           {
               [ActivatorUtilitiesConstructor]
               public Service2(Dependency1 dependency1, Dependency2 dependency2, Dependency3 dependency3)
               {
               }
   
               public Service2(Dependency1 dependency1, Dependency3 dependency3)
               {
                   throw new Exception("This should not be called.");
               }
           }
   
           [Fact]
           public void CreateInstance_WithActivatorUtilitiesConstructorBeingSecond_ShouldChooseMarkedCtor()
           {
               // Arrange
               var dependency1 = new Dependency1();
               var dependency3 = new Dependency3();
   
               var provider = new ServiceCollection()
                   .AddScoped<Dependency2>()
                   .BuildServiceProvider();
   
               // Act & Assert
               ActivatorUtilities.CreateInstance<Service1>(provider, dependency1, dependency3); // This works.
           }
   
           [Fact]
           public void CreateInstance_WithActivatorUtilitiesConstructorBeingFirst_ShouldChooseMarkedCtor()
           {
               // Arrange
               var dependency1 = new Dependency1();
               var dependency3 = new Dependency3();
   
               var provider = new ServiceCollection()
                   .AddScoped<Dependency2>()
                   .BuildServiceProvider();
   
               // Act & Assert
               ActivatorUtilities.CreateInstance<Service2>(provider, dependency1, dependency3); // This fails.
           }
       }
   }

3. See error This should not be called. when constructor marked with ActivatorUtilitiesConstructorAttribute is defined first, but no error when it is defined second.

Expected behavior

I expect ActivatorUtilitiesConstructorAttribute to be respected regardless of the order in which constructors were defined.

Additional context

The given example is reproduced using 3 dependencies. Removing one dependency makes both tests pass. Maybe this will help to get on a right path.

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[maryamariyan]

Closing as dupe of #46132 since there is more discussion there

[steveharter]

Note that this issue was closed, but there are still issues with the attribute not working. For example adding this to the original repro fails:

        public class Service3
        {
            [ActivatorUtilitiesConstructor]
            public Service3(Dependency1 dependency1, Dependency3 dependency3)
            {
            }

            public Service3(Dependency1 dependency1, Dependency2 dependency2, object? o)
            {
                throw new Exception("This should not be called.");
            }
        }

        [Fact]
        public void Test()
        {
            var dependency1 = new Dependency1();
            var dependency3 = new Dependency3();

            var provider = new ServiceCollection()
                .AddScoped<Dependency2>()
                .BuildServiceProvider();

            // This should call (d1, d3) but instead calls (d1, d2, null).
            ActivatorUtilities.CreateInstance<Service3>(provider, dependency1, dependency3); 

        }