Add empty service scopes (#3078)

src/Discord.Net.Interactions/Builders/ModuleBuilder.cs

@@ -467,12 +467,13 @@ namespace Discord.Interactions.Builders
         {
             if (TypeInfo is not null && ModuleClassBuilder.IsValidModuleDefinition(TypeInfo))
             {
-                IServiceScope scope = null;
+                using var scope = InteractionService._autoServiceScopes
-                if (interactionService._autoServiceScopes)
+                    ? services.CreateScope()
-                {
+                    : null;
-                    scope = services?.CreateScope();
+
-                    services = scope?.ServiceProvider ?? EmptyServiceProvider.Instance;
+                services = (InteractionService._autoServiceScopes
-                }
+                    ? scope?.ServiceProvider
+                    : services) ?? EmptyServiceProvider.Instance;
 
                 var instance = ReflectionUtils<IInteractionModuleBase>.CreateObject(TypeInfo, interactionService, services);
 
@@ -482,12 +483,10 @@ namespace Discord.Interactions.Builders
                     var moduleInfo = new ModuleInfo(this, interactionService, services, parent);
                     instance.OnModuleBuilding(interactionService, moduleInfo);
 
-                    scope?.Dispose();
                     return moduleInfo;
                 }
                 finally
                 {
-                    scope?.Dispose();
                     (instance as IDisposable)?.Dispose();
                 }
             }

src/Discord.Net.Interactions/Utilities/EmptyServiceProvider.cs

@@ -1,11 +1,31 @@
+using Microsoft.Extensions.DependencyInjection;
 using System;
 
-namespace Discord.Interactions
+namespace Discord.Interactions;
-{
-    internal class EmptyServiceProvider : IServiceProvider
-    {
-        public static EmptyServiceProvider Instance => new EmptyServiceProvider();
 
-        public object GetService(Type serviceType) => null;
+internal class EmptyServiceProvider : IServiceProvider
+{
+    public static EmptyServiceProvider Instance => new ();
+
+    public object GetService(Type serviceType)
+    {
+        if (serviceType == typeof(IServiceScopeFactory))
+            return EmptyServiceScopeFactory.Instance;
+
+        return null;
     }
 }
+
+internal class EmptyServiceScopeFactory : IServiceScopeFactory
+{
+    public static EmptyServiceScopeFactory Instance => new ();
+
+    public IServiceScope CreateScope() => new EmptyServiceScope();
+}
+
+internal class EmptyServiceScope : IServiceScope
+{
+    public IServiceProvider ServiceProvider => EmptyServiceProvider.Instance;
+
+    public void Dispose() { }
+}