fixed: #546 for v5.3.1

Author: dadhi

src/DryIoc/Container.cs

@@ -12191,7 +12191,10 @@ private static void MatchOpenGenericConstraints(Type[] implTypeParams, Type[] im
                     var implTypeParamConstraint = implTypeParamConstraints[j];
                     if (implTypeParamConstraint != implTypeArg && implTypeParamConstraint.IsOpenGeneric())
                     {
-                        var implTypeArgArgs = implTypeArg.IsGenericType ? implTypeArg.GetGenericArguments() : implTypeArg.One();
+                        var implTypeArgArgs = 
+                            implTypeArg.IsGenericType ? implTypeArg.GetGenericArguments() :
+                            implTypeArg.IsArray ? implTypeArg.GetElementType().One() :
+                            implTypeArg.One();
                         var implTypeParamConstraintParams = implTypeParamConstraint.GetGenericArguments();
 
                         constraintMatchFound = MatchServiceWithImplementedTypeParams(
@@ -12202,8 +12205,7 @@ private static void MatchOpenGenericConstraints(Type[] implTypeParams, Type[] im
         }
 
         private static bool MatchServiceWithImplementedTypeParams(
-            Type[] resultImplArgs, Type[] implParams, Type[] serviceParams, Type[] serviceArgs,
-            int resultCount = 0)
+            Type[] resultImplArgs, Type[] implParams, Type[] serviceParams, Type[] serviceArgs)
         {
             if (serviceArgs.Length != serviceParams.Length)
                 return false;

test/DryIoc.IssuesTests/GHIssue546_Generic_type_constraint_resolution_doesnt_see_arrays_as_IEnumerable.cs

@@ -0,0 +1,57 @@
+using System.Collections.Generic;
+using NUnit.Framework;
+
+namespace DryIoc.IssuesTests
+{
+    [TestFixture]
+    public class GHIssue546_Generic_type_constraint_resolution_doesnt_see_arrays_as_IEnumerable : ITest
+    {
+        public int Run()
+        {
+            Test1();
+            Test2();
+            return 2;
+        }
+
+        [Test]
+        public void Test1()
+        {
+            // Works - type is compliant with the generic constraints - would not compile otherwise.
+            var q = new MyThing<int[], int>();
+
+            var container = new Container();
+
+            container.Register(typeof(IMyThing<>), typeof(MyThing<,>), Reuse.ScopedOrSingleton);
+
+            // Fails when we try to resolve it through the container
+            var y = container.Resolve<IMyThing<int[]>>();
+            Assert.IsInstanceOf<MyThing<int[], int>>(y);
+        }
+
+        [Test]
+        public void Test2()
+        {
+            var container = new Container();
+
+            container.Register(typeof(IMyThing<>), typeof(MyThing<,>), Reuse.ScopedOrSingleton);
+
+            // Works - constraint of IEnumerable<TValue> brings int from List<int> into the 2nd generic parameter.
+            var x = container.Resolve<IMyThing<List<int>>>();
+            Assert.IsInstanceOf<MyThing<List<int>, int>>(x);
+
+            // Works - type is compliant with the generic constraints - would not compile otherwise.
+            var q = new MyThing<int[], int>();
+
+            // Fails when we try to resolve it through the container
+            var y = container.Resolve<IMyThing<int[]>>();
+            Assert.IsInstanceOf<MyThing<int[], int>>(y);
+        }
+
+        public interface IMyThing<T> { }
+        public interface IMyThing<T, TValue> : IMyThing<T>
+            where T : IEnumerable<TValue> { }
+
+        public class MyThing<T, TValue> : IMyThing<T, TValue>
+            where T : IEnumerable<TValue> { }
+    }
+}

test/DryIoc.TestRunner/Program.cs

@@ -64,7 +64,8 @@ void Run(Func<int> run, string name = null)
                 new GHIssue508_Throws_when_lazy_resolve_after_explicit_create_using_factory_func_from_within_scope(),
                 new GHIssue471_Regression_v5_using_Rules_SelectKeyedOverDefaultFactory(),
                 new GHIssue532_WithUseInterpretation_still_use_DynamicMethod_and_ILEmit(),
-                new GHIssue536_DryIoc_Exception_in_a_Constructor_of_a_Dependency_does_tunnel_through_Resolve_call()
+                new GHIssue536_DryIoc_Exception_in_a_Constructor_of_a_Dependency_does_tunnel_through_Resolve_call(),
+                new GHIssue546_Generic_type_constraint_resolution_doesnt_see_arrays_as_IEnumerable()
             };
 
             // Parallel.ForEach(tests, x => Run(x.Run)); // todo: @perf enable and test when more tests are added