- add validation for multiton factories

LightweightIocContainer/LightweightIocContainer.xml

@@ -1351,6 +1351,11 @@
             The <see cref="T:System.Type"/> of the multiton scope
             </summary>
         </member>
+        <member name="M:LightweightIocContainer.Registrations.MultitonRegistration`2.ValidateFactory">
+            <summary>
+            Validate the <see cref="P:LightweightIocContainer.Registrations.RegistrationBase.Factory"/>
+            </summary>
+        </member>
         <member name="T:LightweightIocContainer.Registrations.OpenGenericRegistration">
             <summary>
             <see cref="T:LightweightIocContainer.Interfaces.Registrations.IRegistration"/> for open generic types

LightweightIocContainer/Registrations/MultitonRegistration.cs

@@ -3,6 +3,8 @@
 // Copyright(c) 2019 SimonG. All Rights Reserved.
 
 using System;
+using System.Linq;
+using LightweightIocContainer.Exceptions;
 using LightweightIocContainer.Interfaces;
 using LightweightIocContainer.Interfaces.Registrations;
 
@@ -30,5 +32,22 @@ namespace LightweightIocContainer.Registrations
         /// The <see cref="Type"/> of the multiton scope
         /// </summary>
         public Type Scope { get; }
+
+        /// <summary>
+        /// Validate the <see cref="RegistrationBase.Factory"/>
+        /// </summary>
+        protected override void ValidateFactory()
+        {
+            if (Factory == null)
+                return;
+            
+            if (Factory.CreateMethods.Any(c => c.GetParameters().Length == 0))
+                throw new InvalidFactoryRegistrationException($"Create methods without parameters are not valid for multitons (Type: {InterfaceType}).");
+            
+            if (Factory.CreateMethods.Any(c => c.GetParameters()[0].ParameterType != Scope))
+                throw new InvalidFactoryRegistrationException($"Create methods without scope type ({Scope}) as first parameter are not valid for multitons (Type: {InterfaceType}).");
+            
+            base.ValidateFactory();
+        }
     }
 }

LightweightIocContainer/Registrations/RegistrationBase.cs

@@ -173,12 +173,12 @@ namespace LightweightIocContainer.Registrations
         /// Validate the <see cref="Factory"/>
         /// </summary>
         /// <exception cref="InvalidFactoryRegistrationException">No create method that can create the <see cref="InterfaceType"/></exception>
-        private void ValidateFactory()
+        protected virtual void ValidateFactory()
         {
             if (Factory == null)
                 return;
             
-            if (Factory.CreateMethods.Any(c => c.ReturnType == InterfaceType) != true)
+            if (Factory.CreateMethods.All(c => c.ReturnType != InterfaceType))
                 throw new InvalidFactoryRegistrationException($"No create method that can create {InterfaceType}.");
         }
         

Test.LightweightIocContainer/FluentFactoryRegistrationTest.cs

@@ -61,21 +61,30 @@ namespace Test.LightweightIocContainer
         {
             ITest Create();
             ITest Create(string name);
-            ITest Create(MultitonScope scope);
             ITest CreateTest(string name = null);
             ITest Create(byte id);
-
-            void ClearMultitonInstance<T>();
         }
-
+        
         private class TestFactory : ITestFactory
         {
             public ITest Create() => new Test();
             public ITest Create(string name) => throw new System.NotImplementedException();
-            public ITest Create(MultitonScope scope) => throw new System.NotImplementedException();
             public ITest CreateTest(string name = null) => throw new System.NotImplementedException();
             public ITest Create(byte id) => throw new System.NotImplementedException();
-            public void ClearMultitonInstance<T>() => throw new System.NotImplementedException();
+        }
+        
+        [UsedImplicitly]
+        public interface IMultitonTestFactory
+        {
+            ITest Create(MultitonScope scope);
+            void ClearMultitonInstance<T>();
+        }
+        
+        [UsedImplicitly]
+        public interface IInvalidMultitonTestFactory
+        {
+            ITest Create(MultitonScope scope);
+            ITest Create(int number);
         }
         
         [UsedImplicitly]
@@ -188,12 +197,12 @@ namespace Test.LightweightIocContainer
         [Test]
         public void TestResolveMultitonFromFactory()
         {
-            _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<ITestFactory>());
+            _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<IMultitonTestFactory>());
         
             MultitonScope scope1 = new();
             MultitonScope scope2 = new();
         
-            ITestFactory testFactory = _iocContainer.Resolve<ITestFactory>();
+            IMultitonTestFactory testFactory = _iocContainer.Resolve<IMultitonTestFactory>();
         
             ITest resolvedTest1 = testFactory.Create(scope1);
             ITest resolvedTest2 = testFactory.Create(scope1);
@@ -207,12 +216,12 @@ namespace Test.LightweightIocContainer
         [Test]
         public void TestResolveMultitonFromFactoryClearInstances()
         {
-            _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<ITestFactory>());
+            _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<IMultitonTestFactory>());
         
             MultitonScope scope1 = new();
             MultitonScope scope2 = new();
         
-            ITestFactory testFactory = _iocContainer.Resolve<ITestFactory>();
+            IMultitonTestFactory testFactory = _iocContainer.Resolve<IMultitonTestFactory>();
         
             ITest resolvedTest1 = testFactory.Create(scope1);
             ITest resolvedTest2 = testFactory.Create(scope1);
@@ -232,6 +241,14 @@ namespace Test.LightweightIocContainer
             Assert.AreNotSame(resolvedTest3, resolvedTest5);
         }
 
+        [Test]
+        public void InvalidMultitonFactoryRegistrationFactoryWithoutParameter() => 
+            Assert.Throws<InvalidFactoryRegistrationException>(() => _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<ITestFactory>()));
+        
+        [Test]
+        public void InvalidMultitonFactoryRegistrationFactoryWithoutScopeAsFirstParameter() => 
+            Assert.Throws<InvalidFactoryRegistrationException>(() => _iocContainer.Register(r => r.AddMultiton<ITest, Test, MultitonScope>().WithFactory<IInvalidMultitonTestFactory>()));
+
         [Test]
         public void TestInvalidCreateMethodReturnType() => 
             Assert.Throws<InvalidFactoryRegistrationException>(() => _iocContainer.Register(r => r.Add<ITest, Test>().WithFactory<ITestFactoryWrongReturn>()));