Fix: lifetime check methods return false for unregistered services instead of throwing

Co-authored-by: AGiorgetti <246067+AGiorgetti@users.noreply.github.com>

Author: Copilot

Changelog.md

@@ -4,6 +4,7 @@
 
 ### Bug Fixes
 
+- `IServiceCollection` lifetime check methods (`IsTransientServiceRegistered`, `IsScopedServiceRegistered`, `IsSingletonServiceRegistered`, and their keyed variants) now return `false` instead of throwing `InvalidOperationException` when the service is not registered.
 - Fixed `ResolutionContext` stack corruption in `PatchForResolutionContextTracking` when a factory delegate throws an exception. Push/Pop calls are now wrapped in `try/finally` for all 4 registration paths (non-keyed/keyed × factory/type).
 - Fixed bidirectional `IsAssignableFrom` check in `GetServiceDescriptors` method that incorrectly returned unrelated base-type registrations [#19](https://github.com/PrimordialCode/Mammoth.Extensions.DependencyInjection/issues/19).
   - The method now uses unidirectional matching: `serviceType == serviceDescriptor.ServiceType || serviceType.IsAssignableFrom(serviceDescriptor.ServiceType)`.

src/Mammoth.Extensions.DependencyInjection.Tests/ServiceCollectionExtensions.Registration.Tests.cs

@@ -0,0 +1,129 @@
+using Microsoft.Extensions.DependencyInjection;
+using Mammoth.Cqrs.Infrastructure.Tests.Infrastructure;
+
+namespace Mammoth.Extensions.DependencyInjection.Tests
+{
+	[TestClass]
+	public class ServiceCollectionExtensionsRegistrationTests
+	{
+		[TestMethod]
+		public void IsTransientServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsTransientServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsTransientServiceRegistered(typeof(TestService)));
+		}
+
+		[TestMethod]
+		public void IsScopedServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsScopedServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsScopedServiceRegistered(typeof(TestService)));
+		}
+
+		[TestMethod]
+		public void IsSingletonServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsSingletonServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsSingletonServiceRegistered(typeof(TestService)));
+		}
+
+		[TestMethod]
+		public void IsKeyedSingletonServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsKeyedSingletonServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedSingletonServiceRegistered(typeof(TestService), "key"));
+		}
+
+		[TestMethod]
+		public void IsKeyedScopedServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsKeyedScopedServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedScopedServiceRegistered(typeof(TestService), "key"));
+		}
+
+		[TestMethod]
+		public void IsKeyedTransientServiceRegistered_Returns_False_When_Service_Not_Registered()
+		{
+			var serviceCollection = new ServiceCollection();
+
+			Assert.IsFalse(serviceCollection.IsKeyedTransientServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedTransientServiceRegistered(typeof(TestService), "key"));
+		}
+
+		[TestMethod]
+		public void IsTransientServiceRegistered_Returns_True_When_Registered_As_Transient()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddTransient<TestService>();
+
+			Assert.IsTrue(serviceCollection.IsTransientServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsScopedServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsSingletonServiceRegistered<TestService>());
+		}
+
+		[TestMethod]
+		public void IsScopedServiceRegistered_Returns_True_When_Registered_As_Scoped()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddScoped<TestService>();
+
+			Assert.IsFalse(serviceCollection.IsTransientServiceRegistered<TestService>());
+			Assert.IsTrue(serviceCollection.IsScopedServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsSingletonServiceRegistered<TestService>());
+		}
+
+		[TestMethod]
+		public void IsSingletonServiceRegistered_Returns_True_When_Registered_As_Singleton()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddSingleton<TestService>();
+
+			Assert.IsFalse(serviceCollection.IsTransientServiceRegistered<TestService>());
+			Assert.IsFalse(serviceCollection.IsScopedServiceRegistered<TestService>());
+			Assert.IsTrue(serviceCollection.IsSingletonServiceRegistered<TestService>());
+		}
+
+		[TestMethod]
+		public void IsKeyedTransientServiceRegistered_Returns_True_When_Registered_As_Keyed_Transient()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddKeyedTransient<TestService>("key");
+
+			Assert.IsTrue(serviceCollection.IsKeyedTransientServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedScopedServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedSingletonServiceRegistered<TestService>("key"));
+		}
+
+		[TestMethod]
+		public void IsKeyedScopedServiceRegistered_Returns_True_When_Registered_As_Keyed_Scoped()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddKeyedScoped<TestService>("key");
+
+			Assert.IsFalse(serviceCollection.IsKeyedTransientServiceRegistered<TestService>("key"));
+			Assert.IsTrue(serviceCollection.IsKeyedScopedServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedSingletonServiceRegistered<TestService>("key"));
+		}
+
+		[TestMethod]
+		public void IsKeyedSingletonServiceRegistered_Returns_True_When_Registered_As_Keyed_Singleton()
+		{
+			var serviceCollection = new ServiceCollection();
+			serviceCollection.AddKeyedSingleton<TestService>("key");
+
+			Assert.IsFalse(serviceCollection.IsKeyedTransientServiceRegistered<TestService>("key"));
+			Assert.IsFalse(serviceCollection.IsKeyedScopedServiceRegistered<TestService>("key"));
+			Assert.IsTrue(serviceCollection.IsKeyedSingletonServiceRegistered<TestService>("key"));
+		}
+	}
+}

src/Mammoth.Extensions.DependencyInjection/ServiceCollectionExtensions.Registration.cs

@@ -84,7 +84,7 @@ public static bool IsTransientServiceRegistered(this IServiceCollection services
 			}
 
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: false);
-			return descriptors.Last().Lifetime == ServiceLifetime.Transient;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Transient;
 		}
 
 		/// <summary>
@@ -112,7 +112,7 @@ public static bool IsScopedServiceRegistered(this IServiceCollection services, T
 			}
 
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: false);
-			return descriptors.Last().Lifetime == ServiceLifetime.Scoped;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Scoped;
 		}
 
 		/// <summary>
@@ -140,7 +140,7 @@ public static bool IsSingletonServiceRegistered(this IServiceCollection services
 			}
 
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: false);
-			return descriptors.Last().Lifetime == ServiceLifetime.Singleton;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Singleton;
 		}
 
 		/// <summary>
@@ -176,7 +176,7 @@ public static bool IsKeyedSingletonServiceRegistered(this IServiceCollection ser
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: true)
 				.Where(d => d.ServiceKey == serviceKey)
 				.ToArray();
-			return descriptors.Last().Lifetime == ServiceLifetime.Singleton;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Singleton;
 		}
 
 		/// <summary>
@@ -212,7 +212,7 @@ public static bool IsKeyedScopedServiceRegistered(this IServiceCollection servic
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: true)
 				.Where(d => d.ServiceKey == serviceKey)
 				.ToArray();
-			return descriptors.Last().Lifetime == ServiceLifetime.Scoped;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Scoped;
 		}
 
 		/// <summary>
@@ -248,7 +248,7 @@ public static bool IsKeyedTransientServiceRegistered(this IServiceCollection ser
 			var descriptors = services.GetServiceDescriptors(serviceType, isKeyedService: true)
 				.Where(d => d.ServiceKey == serviceKey)
 				.ToArray();
-			return descriptors.Last().Lifetime == ServiceLifetime.Transient;
+			return descriptors.Length > 0 && descriptors[descriptors.Length - 1].Lifetime == ServiceLifetime.Transient;
 		}
 
 		/// <summary>