Add OpenGenericFactoryRegistrationSource only once and only for open generic types.

Author: hypercodeplace

LazyProxy.Autofac.Tests/AutofacExtensionTests.cs

@@ -383,6 +383,50 @@ public void NonLazyRegistrationMutatorMustBeApplied(string name)
             }
         }
 
+        [Theory]
+        [InlineData(null)]
+        [InlineData("name")]
+        public void RegisterLazyMustAddOpenGenericFactoryRegistrationSourceOnlyOnceForOpenGenericTypes(
+            string name)
+        {
+            var containerBuilder = new ContainerBuilder();
+            containerBuilder.RegisterLazy(typeof(IGenericService<,,>), typeof(GenericService<,,>), name);
+            containerBuilder.RegisterLazy(typeof(IGenericService2<>), typeof(GenericService2<>), name);
+
+            using (var container = containerBuilder.Build())
+            {
+                var count = container.ComponentRegistry.Sources
+                    .OfType<OpenGenericFactoryRegistrationSource>()
+                    .Count();
+
+                Assert.Equal(1, count);
+            }
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("name")]
+        public void RegisterLazyMustNotAddOpenGenericFactoryRegistrationSourceForNonOpenGenericTypes(
+            string name)
+        {
+            var containerBuilder = new ContainerBuilder();
+
+            containerBuilder.RegisterLazy(typeof(IService1), typeof(Service1), name);
+
+            containerBuilder.RegisterLazy(
+                typeof(IGenericService<ParameterType1, ParameterType2, ParameterType3>),
+                typeof(GenericService<ParameterType1, ParameterType2, ParameterType3>), name);
+
+            using (var container = containerBuilder.Build())
+            {
+                var count = container.ComponentRegistry.Sources
+                    .OfType<OpenGenericFactoryRegistrationSource>()
+                    .Count();
+
+                Assert.Equal(0, count);
+            }
+        }
+
         #region Lifetime tests
 
         [Theory]
@@ -790,6 +834,18 @@ public GenericService()
             }
         }
 
+        // ReSharper disable once MemberCanBePrivate.Global
+        public interface IGenericService2<T>
+        {
+            // ReSharper disable once UnusedMember.Global
+            T Get(T arg1);
+        }
+
+        private class GenericService2<T> : IGenericService2<T>
+        {
+            public T Get(T arg1) => arg1;
+        }
+
         #endregion
     }
 }

LazyProxy.Autofac/AutofacExtensions.cs

@@ -12,6 +12,9 @@ namespace LazyProxy.Autofac
     /// </summary>
     public static class AutofacExtensions
     {
+        private const string OpenGenericFactoryRegistrationSourceIsAlreadyAdded =
+            nameof(OpenGenericFactoryRegistrationSourceIsAlreadyAdded);
+
         /// <summary>
         /// Is used to register interface TFrom to class TTo by creation a lazy proxy at runtime.
         /// The real class To will be instantiated only after first method or property execution.
@@ -48,12 +51,16 @@ public static IRegistrationBuilder<object, SimpleActivatorData, SingleRegistrati
                 throw new NotSupportedException("The lazy registration is supported only for interfaces.");
             }
 
-            builder.RegisterSource<OpenGenericFactoryRegistrationSource>();
-
             var registrationName = Guid.NewGuid().ToString();
 
             if (typeTo.IsGenericTypeDefinition)
             {
+                if (!builder.Properties.ContainsKey(OpenGenericFactoryRegistrationSourceIsAlreadyAdded))
+                {
+                    builder.RegisterSource<OpenGenericFactoryRegistrationSource>();
+                    builder.Properties.Add(OpenGenericFactoryRegistrationSourceIsAlreadyAdded, true);
+                }
+
                 var nonLazyRegistration = builder.RegisterGeneric(typeTo).Named(registrationName, typeFrom);
                 nonLazyRegistrationMutator?.Mutate(nonLazyRegistration);
             }