From 96e2fe04a083efcd1e09d1da1afa9786d378352f Mon Sep 17 00:00:00 2001
From: rizi <rene.riedinger@gmail.com>
Date: Mon, 18 Nov 2024 18:37:51 +0100
Subject: [PATCH] Use 'keyed service' code only for .net 8 and newer versions

---
 ...closed_generic_interface_registration_check.cs |  4 +++-
 .../IKeyedServiceProvider_compliance.cs           |  4 ++--
 src/Lamar/IServiceContext.cs                      |  5 ++++-
 src/Lamar/IoC/Instances/Instance.cs               |  5 +++--
 src/Lamar/ServiceGraph.cs                         | 15 ++++++++++++---
 5 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/src/Lamar.AspNetCoreTests/Bugs/Bug_395_keyed_service_closed_generic_interface_registration_check.cs b/src/Lamar.AspNetCoreTests/Bugs/Bug_395_keyed_service_closed_generic_interface_registration_check.cs
index 9d5236f4..1f1cc170 100644
--- a/src/Lamar.AspNetCoreTests/Bugs/Bug_395_keyed_service_closed_generic_interface_registration_check.cs
+++ b/src/Lamar.AspNetCoreTests/Bugs/Bug_395_keyed_service_closed_generic_interface_registration_check.cs
@@ -9,6 +9,7 @@
 
 namespace Lamar.AspNetCoreTests.Bugs;
 
+#if NET8_0_OR_GREATER
 public class Bug_395_keyed_service_closed_generic_interface_registration_check
 {
     class ClassA {}
@@ -45,4 +46,5 @@ public void do_not_blow_up()
                 .ShouldNotBeNull();
         }
     }
-}
\ No newline at end of file
+}
+#endif
\ No newline at end of file
diff --git a/src/Lamar.Testing/IoC/Acceptance/IKeyedServiceProvider_compliance.cs b/src/Lamar.Testing/IoC/Acceptance/IKeyedServiceProvider_compliance.cs
index be6cdaee..bfc28684 100644
--- a/src/Lamar.Testing/IoC/Acceptance/IKeyedServiceProvider_compliance.cs
+++ b/src/Lamar.Testing/IoC/Acceptance/IKeyedServiceProvider_compliance.cs
@@ -8,7 +8,7 @@ namespace Lamar.Testing.IoC.Acceptance;
 
 public class IKeyedServiceProvider_compliance
 {
-    #region sample_adding_keyed_services
+    #if NET8_0_OR_GREATER
 
     [Fact]
     public void register_by_name_using_dot_net_core_syntax()
@@ -44,5 +44,5 @@ public void register_by_name_using_dot_net_core_syntax()
             .ShouldNotBeSameAs(container.GetKeyedService<CWidget>("C3"));
     }
 
-    #endregion
+    #endif
 }
diff --git a/src/Lamar/IServiceContext.cs b/src/Lamar/IServiceContext.cs
index 86dddcb1..a70ea3a9 100644
--- a/src/Lamar/IServiceContext.cs
+++ b/src/Lamar/IServiceContext.cs
@@ -8,7 +8,10 @@
 
 namespace Lamar;
 
-public interface IServiceContext : IServiceProvider, IDisposable, IAsyncDisposable, IKeyedServiceProvider
+public interface IServiceContext : IServiceProvider, IDisposable, IAsyncDisposable
+#if NET8_0_OR_GREATER
+    , IKeyedServiceProvider
+#endif
 {
     /// <summary>
     ///     Provides queryable access to the configured serviceType's and Instances of this Container.
diff --git a/src/Lamar/IoC/Instances/Instance.cs b/src/Lamar/IoC/Instances/Instance.cs
index c3f3c3e3..cb6d9398 100644
--- a/src/Lamar/IoC/Instances/Instance.cs
+++ b/src/Lamar/IoC/Instances/Instance.cs
@@ -106,10 +106,12 @@ internal IEnumerable<Assembly> ReferencedAssemblies()
 
     public static Instance For(ServiceDescriptor service)
     {
+        #if NET8_0_OR_GREATER
         if (service.IsKeyedService)
         {
             var name = service.ServiceKey?.ToString();
             Instance instance = null;
+           
             if (service.KeyedImplementationInstance != null)
             {
                 instance = new ObjectInstance(service.ServiceType, service.KeyedImplementationInstance);
@@ -136,9 +138,8 @@ public static Instance For(ServiceDescriptor service)
             if (name.IsNotEmpty()) instance.Name = name;
             
             return instance;
-
-
         }
+        #endif
 
         
         if (service.ImplementationInstance is Instance i)
diff --git a/src/Lamar/ServiceGraph.cs b/src/Lamar/ServiceGraph.cs
index 8c47ed91..8d2c5b8d 100644
--- a/src/Lamar/ServiceGraph.cs
+++ b/src/Lamar/ServiceGraph.cs
@@ -268,9 +268,7 @@ private ServiceFamily buildFamilyForInstanceGroup(IServiceCollection services,
 
     private ServiceFamily buildClosedGenericType(Type serviceType, IServiceCollection services)
     {
-        var closed = services.Where(x => x.ServiceType == serviceType && (x.IsKeyedService
-                ? !x.KeyedImplementationType.IsOpenGeneric()
-                : !x.ImplementationType.IsOpenGeneric()))
+        var closed = services.Where(x => x.ServiceType == serviceType && isKeyedServiceSupported(x))
             .Select(Instance.For);
 
         var templated = services
@@ -297,6 +295,17 @@ private ServiceFamily buildClosedGenericType(Type serviceType, IServiceCollectio
         return new ServiceFamily(serviceType, DecoratorPolicies, instances);
     }
 
+    private static bool isKeyedServiceSupported(ServiceDescriptor serviceDescriptor)
+    {
+        #if NET8_0_OR_GREATER
+         return serviceDescriptor.IsKeyedService
+                    ? !serviceDescriptor.KeyedImplementationType.IsOpenGeneric()
+                    : !serviceDescriptor.ImplementationType.IsOpenGeneric();
+        #endif
+
+        return !serviceDescriptor.ImplementationType.IsOpenGeneric();
+    }
+
     public IEnumerable<Instance> AllInstances()
     {
         var serviceFamilies = _families.Enumerate().Select(x => x.Value).Where(x => x != null).ToArray();