Remove AddHandler from public API

Author: ejsmith

src/Foundatio.Mediator.Abstractions/MediatorExtensions.cs

@@ -57,19 +57,6 @@ public static IServiceCollection AddMediator(this IServiceCollection services, A
         return services.AddMediator(configurationBuilder.Build());
     }
 
-    /// <summary>
-    /// Adds a handler registration to the service collection.
-    /// </summary>
-    /// <param name="services"></param>
-    /// <param name="registration"></param>
-    /// <returns></returns>
-    public static IServiceCollection AddHandler(this IServiceCollection services, HandlerRegistration registration)
-    {
-        services.AddKeyedSingleton(registration.MessageTypeName, registration);
-        services.AddSingleton(registration);
-        return services;
-    }
-
     private static bool IsAssemblyMarkedWithFoundatioHandlerModule(Assembly assembly)
     {
         return assembly.GetCustomAttributes(typeof(FoundatioHandlerModuleAttribute), false).Any();

src/Foundatio.Mediator/DIRegistrationGenerator.cs

@@ -58,8 +58,7 @@ public static void Execute(SourceProductionContext context, List<HandlerInfo> ha
                     source.AppendLine($"services.{lifetimeMethod}<{handler.FullName}>();");
             }
 
-            // Use reflection FullName so nested types resolve with '+' and match runtime Type.FullName keys
-            source.AppendLine($"services.AddHandler(new HandlerRegistration(");
+            source.AppendLine($"AddMediatorHandler(services, new HandlerRegistration(");
             source.AppendLine($"        MessageTypeKey.Get(typeof({handler.MessageType.FullName})),");
             source.AppendLine($"        \"{handlerClassName}\",");
 
@@ -79,8 +78,20 @@ public static void Execute(SourceProductionContext context, List<HandlerInfo> ha
             source.AppendLine();
         }
 
-        source.DecrementIndent().DecrementIndent();
-        source.AppendLine("    }");
+        source.DecrementIndent();
+        source.AppendLine("}");
+
+        source.AppendLine()
+            .AppendLines($$"""
+                           [DebuggerStepThrough]
+                           private static void AddMediatorHandler(IServiceCollection services, HandlerRegistration registration)
+                           {
+                               services.AddKeyedSingleton(registration.MessageTypeName, registration);
+                               services.AddSingleton(registration);
+                           }
+                           """);
+
+        source.DecrementIndent();
         source.AppendLine("}");
 
         context.AddSource($"{className}.g.cs", source.ToString());

tests/Foundatio.Mediator.Tests/GenericMessageTests.cs

@@ -70,7 +70,9 @@ public void RegistersFriendlyGenericKey()
              public record Order(string Id);
              public record EntityAction<T>(T Entity) : IQuery;
 
-             public class OrderActionHandler {
+             public class SomeBaseClass<T> { }
+
+             public class OrderActionHandler : SomeBaseClass<Order> {
                  public Task<Result> HandleAsync(EntityAction<Order> action, CancellationToken ct) => Task.FromResult(Result.Success());
              }
              """;