keep registered trigger instances across pooled context leases

Author: koenbeuk

src/EntityFrameworkCore.Triggered/Internal/TriggerInstanceFactory.cs

@@ -21,10 +21,12 @@ public sealed class TriggerInstanceFactory<TTriggerType> : ITriggerInstanceFacto
     {
         static ObjectFactory? _internalFactory;
 
+        readonly object? _capturedInstance;
         object? _instance;
 
         public TriggerInstanceFactory(object? instance)
         {
+            _capturedInstance = instance;
             _instance = instance;
         }
 
@@ -46,7 +48,7 @@ public object Create(IServiceProvider serviceProvider)
 
         public void ResetState()
         {
-            _instance = null;
+            _instance = _capturedInstance;
         }
 
         public Task ResetStateAsync(CancellationToken cancellationToken = default)

test/EntityFrameworkCore.Triggered.Tests/Infrastructure/ServiceCollectionExtensionsTests.cs

@@ -122,6 +122,32 @@ public void AddTriggeredDbContextPool_ReusesScopedServiceProvider()
             Assert.Single(triggerStub.BeforeSaveInvocations);
         }
 
+        [Fact]
+        public void AddTriggeredDbContextPool_KeepsRegisteredTriggerInstanceAcrossLeases()
+        {
+            var triggerStub = new TriggerStub<TestModel>();
+            var subject = new ServiceCollection();
+            subject.AddTriggeredDbContextPool<TestDbContext>(options => {
+                options.UseInMemoryDatabase(nameof(AddTriggeredDbContextPool_KeepsRegisteredTriggerInstanceAcrossLeases));
+                options.ConfigureWarnings(warningOptions => {
+                    warningOptions.Ignore(CoreEventId.ManyServiceProvidersCreatedWarning);
+                });
+                options.UseTriggers(triggerOptions => triggerOptions.AddTrigger(triggerStub));
+            }, poolSize: 1);
+
+            using var serviceProvider = subject.BuildServiceProvider();
+
+            for (var lease = 0; lease < 3; lease++)
+            {
+                using var scope = serviceProvider.CreateScope();
+                var context = scope.ServiceProvider.GetRequiredService<TestDbContext>();
+                context.TestModels.Add(new TestModel());
+                context.SaveChanges();
+            }
+
+            Assert.Equal(3, triggerStub.BeforeSaveInvocations.Count);
+        }
+
         [Fact]
         public void AddTriggeredDbContextPool_SupportsAScopedLifetime()
         {