From cc104b95ece0b93c4b77a48e5c798e0285304743 Mon Sep 17 00:00:00 2001
From: "Simon G." <simon.gockner@gmail.com>
Date: Thu, 19 Dec 2024 13:03:06 +0100
Subject: [PATCH] - fix validation of open generic type registrations without
 parameter constraints

---
 .../IocValidator.cs                           |  9 +++++--
 .../IocValidatorTest.cs                       | 26 +++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/LightweightIocContainer.Validation/IocValidator.cs b/LightweightIocContainer.Validation/IocValidator.cs
index c4b7bb2..a0d44c8 100644
--- a/LightweightIocContainer.Validation/IocValidator.cs
+++ b/LightweightIocContainer.Validation/IocValidator.cs
@@ -68,8 +68,13 @@ private void TryResolve(Type type, object?[]? arguments, List<Exception> validat
             foreach (Type genericArgument in genericArguments.Where(g => g.IsGenericParameter))
             {
                 Type[] genericParameterConstraints = genericArgument.GetGenericParameterConstraints();
-                object mock = Substitute.For(genericParameterConstraints, []);
-                genericParameters.Add(mock.GetType());
+                if (genericParameterConstraints.Any())
+                {
+                    object mock = Substitute.For(genericParameterConstraints, []);
+                    genericParameters.Add(mock.GetType());
+                }
+                else
+                    genericParameters.Add(typeof(object));
             }
 
             type = type.MakeGenericType(genericParameters.ToArray());
diff --git a/Test.LightweightIocContainer.Validation/IocValidatorTest.cs b/Test.LightweightIocContainer.Validation/IocValidatorTest.cs
index 4fcf85f..02a9038 100644
--- a/Test.LightweightIocContainer.Validation/IocValidatorTest.cs
+++ b/Test.LightweightIocContainer.Validation/IocValidatorTest.cs
@@ -41,6 +41,12 @@ public class Constraint : IConstraint;
     [UsedImplicitly]
     public class GenericTest<T> : IGenericTest<T> where T : IConstraint, new();
     
+    [UsedImplicitly]
+    public interface IGenericTestWithoutConstraint<T>;
+    
+    [UsedImplicitly]
+    public class GenericTestWithoutConstraint<T> : IGenericTestWithoutConstraint<T>;
+    
     [UsedImplicitly]
     public interface IGenericTestFactory
     {
@@ -58,6 +64,15 @@ public GenericParameter(IGenericTest<Constraint> test)
             
         }
     }
+    
+    [UsedImplicitly]
+    public class GenericParameterWithoutConstraint : IGenericParameter
+    {
+        public GenericParameterWithoutConstraint(IGenericTestWithoutConstraint<IParameter> test)
+        {
+            
+        }
+    }
 
     [UsedImplicitly]
     private class TestViewModelDontIgnoreDesignTimeCtor : ITest
@@ -321,6 +336,17 @@ public void TestValidateOpenGenericTypeAsParameter()
         IocValidator validator = new(iocContainer);
         validator.Validate();
     }
+    
+    [Test]
+    public void TestValidateOpenGenericTypeWithoutConstraintAsParameter()
+    {
+        IocContainer iocContainer = new();
+        iocContainer.Register(r => r.AddOpenGenerics(typeof(IGenericTestWithoutConstraint<>), typeof(GenericTestWithoutConstraint<>)));
+        iocContainer.Register(r => r.Add<IGenericParameter, GenericParameterWithoutConstraint>());
+
+        IocValidator validator = new(iocContainer);
+        validator.Validate();
+    }
 
     private void AssertNoMatchingConstructorFoundForType<T>(AggregateException aggregateException)
     {