From 997153d956bf18deb498ca5cf933f825c7949552 Mon Sep 17 00:00:00 2001
From: Eugene Baranov <220614+eugbaranov@users.noreply.github.com>
Date: Tue, 30 Oct 2018 00:33:31 +0000
Subject: [PATCH] Inherit Registered callback in child scopes (closes #218)

---
 src/Autofac/Builder/MetadataKeys.cs           |  2 ++
 .../Core/Registration/ComponentRegistry.cs    | 32 ++++++++++++++---
 test/Autofac.Test/ModuleTests.cs              | 36 +++++++++++++++++++
 3 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/src/Autofac/Builder/MetadataKeys.cs b/src/Autofac/Builder/MetadataKeys.cs
index 8e068b9a0..1465a7f91 100644
--- a/src/Autofac/Builder/MetadataKeys.cs
+++ b/src/Autofac/Builder/MetadataKeys.cs
@@ -34,5 +34,7 @@ internal static class MetadataKeys
         internal const string StartOnActivatePropertyKey = "__StartOnActivate";
 
         internal const string ContainerBuildOptions = "__ContainerBuildOptions";
+
+        internal const string RegisteredPropertyKey = "__RegisteredKey";
     }
 }
diff --git a/src/Autofac/Core/Registration/ComponentRegistry.cs b/src/Autofac/Core/Registration/ComponentRegistry.cs
index 4cf9ebd8d..f4ba4fa2e 100644
--- a/src/Autofac/Core/Registration/ComponentRegistry.cs
+++ b/src/Autofac/Core/Registration/ComponentRegistry.cs
@@ -207,8 +207,7 @@ protected virtual void AddRegistration(IComponentRegistration registration, bool
 
             _registrations.Add(registration);
 
-            var handler = Registered;
-            handler?.Invoke(this, new ComponentRegisteredEventArgs(this, registration));
+            GetRegistered()?.Invoke(this, new ComponentRegisteredEventArgs(this, registration));
         }
 
         /// <summary>
@@ -266,7 +265,24 @@ public IEnumerable<IComponentRegistration> DecoratorsFor(IComponentRegistration
         /// Fired whenever a component is registered - either explicitly or via a
         /// <see cref="IRegistrationSource"/>.
         /// </summary>
-        public event EventHandler<ComponentRegisteredEventArgs> Registered;
+        public event EventHandler<ComponentRegisteredEventArgs> Registered
+        {
+            add
+            {
+                lock (_synchRoot)
+                {
+                    Properties[MetadataKeys.RegisteredPropertyKey] = GetRegistered() + value;
+                }
+            }
+
+            remove
+            {
+                lock (_synchRoot)
+                {
+                    Properties[MetadataKeys.RegisteredPropertyKey] = GetRegistered() - value;
+                }
+            }
+        }
 
         /// <summary>
         /// Add a registration source that will provide registrations on-the-fly.
@@ -360,5 +376,13 @@ private ServiceRegistrationInfo GetServiceInfo(Service service)
             _serviceInfo.Add(service, info);
             return info;
         }
+
+        private EventHandler<ComponentRegisteredEventArgs> GetRegistered()
+        {
+            if (Properties.TryGetValue(MetadataKeys.RegisteredPropertyKey, out var registered))
+                return (EventHandler<ComponentRegisteredEventArgs>)registered;
+
+            return null;
+        }
     }
-}
+}
\ No newline at end of file
diff --git a/test/Autofac.Test/ModuleTests.cs b/test/Autofac.Test/ModuleTests.cs
index 3b25ae0cd..c5d4406a1 100644
--- a/test/Autofac.Test/ModuleTests.cs
+++ b/test/Autofac.Test/ModuleTests.cs
@@ -59,6 +59,42 @@ public void AttachesToRegistrations()
             Assert.Equal(container.ComponentRegistry.Registrations.Count(), attachingModule.Registrations.Count);
         }
 
+        [Fact]
+        public void AttachesToRegistrationsInScope()
+        {
+            var attachingModule = new AttachingModule();
+            Assert.Equal(0, attachingModule.Registrations.Count);
+
+            var builder = new ContainerBuilder();
+            builder.RegisterModule(attachingModule);
+
+            using (var container = builder.Build())
+            using (var scope = container.BeginLifetimeScope(c => c.RegisterType(typeof(int))))
+            {
+                var expected = container.ComponentRegistry.Registrations.Count() + scope.ComponentRegistry.Registrations.Count();
+                Assert.Equal(expected, attachingModule.Registrations.Count);
+            }
+        }
+
+        [Fact]
+        public void AttachesToRegistrationsInNestedScope()
+        {
+            var attachingModule = new AttachingModule();
+            Assert.Equal(0, attachingModule.Registrations.Count);
+
+            var builder = new ContainerBuilder();
+            builder.RegisterModule(attachingModule);
+
+            using (var container = builder.Build())
+            using (var outerScope = container.BeginLifetimeScope(c => c.RegisterType(typeof(int))))
+            using (var innerScope = outerScope.BeginLifetimeScope(c => c.RegisterType(typeof(double))))
+            {
+                var expected = container.ComponentRegistry.Registrations.Count()
+                    + outerScope.ComponentRegistry.Registrations.Count() + innerScope.ComponentRegistry.Registrations.Count();
+                Assert.Equal(expected, attachingModule.Registrations.Count);
+            }
+        }
+
         internal class ModuleExposingThisAssembly : Module
         {
             public Assembly ModuleThisAssembly