correct an issue with constructors using interfaces for singleton injeciton.

Author: DerekGooding

SimpleInjection/Injection/Host.cs

@@ -113,7 +113,7 @@ private static void ProcessServicesWithNoDependencies(List<ServiceDescriptor> re
         }
     }
 
-    private void ProcessRemainingServices(List<ServiceDescriptor> result, List<ServiceDescriptor> remaining)
+    private static void ProcessRemainingServices(List<ServiceDescriptor> result, List<ServiceDescriptor> remaining)
     {
         var lastCount = int.MaxValue;
         while (remaining.Count > 0 && lastCount != remaining.Count)
@@ -124,7 +124,7 @@ private void ProcessRemainingServices(List<ServiceDescriptor> result, List<Servi
             {
                 var descriptor = remaining[i];
                 var allDependenciesResolved = descriptor.Dependencies.All(dep =>
-                    _serviceDescriptors.Any(sd => sd.ServiceType == dep && result.Contains(sd)));
+                    CanResolveDependency(dep, result));
 
                 if (allDependenciesResolved)
                 {
@@ -141,6 +141,20 @@ private void ProcessRemainingServices(List<ServiceDescriptor> result, List<Servi
         }
     }
 
+    private static bool CanResolveDependency(Type dependencyType, List<ServiceDescriptor> processedDescriptors)
+    {
+        // Check if we have a direct match (concrete type)
+        if (processedDescriptors.Any(sd => sd.ServiceType == dependencyType))
+            return true;
+
+        // If it's an interface, check if we have a concrete implementation
+        return dependencyType.IsInterface &&
+               processedDescriptors.Any(sd =>
+               dependencyType.IsAssignableFrom(sd.ServiceType) &&
+               !sd.ServiceType.IsInterface &&
+               !sd.ServiceType.IsAbstract);
+    }
+
     private void CreateFactory(ServiceDescriptor descriptor)
     {
         switch (descriptor.Lifetime)

SimpleInjection/SimpleInjection.csproj

@@ -8,7 +8,7 @@
 
 	<GeneratePackageOnBuild>true</GeneratePackageOnBuild>
 	<PackageId>SimpleInjection</PackageId>
-	<Version>0.9.6.5</Version>
+	<Version>0.9.6.6</Version>
 	<Authors>Derek Gooding</Authors>
 	<Company>Derek Gooding</Company>
 	<Description>