test(notification-outbox): cover Email adapter permanent/cancellation arms, align error casing

src/ScadaLink.NotificationOutbox/Delivery/EmailNotificationDeliveryAdapter.cs

@@ -61,21 +61,21 @@ public sealed class EmailNotificationDeliveryAdapter : INotificationDeliveryAdap
         if (list == null)
         {
             return DeliveryOutcome.Permanent(
-                $"notification list '{notification.ListName}' not found");
+                $"Notification list '{notification.ListName}' not found");
         }
 
         var recipients = await _repository.GetRecipientsByListIdAsync(list.Id, cancellationToken);
         if (recipients.Count == 0)
         {
             return DeliveryOutcome.Permanent(
-                $"notification list '{notification.ListName}' has no recipients");
+                $"Notification list '{notification.ListName}' has no recipients");
         }
 
         var smtpConfigs = await _repository.GetAllSmtpConfigurationsAsync(cancellationToken);
         var smtpConfig = smtpConfigs.FirstOrDefault();
         if (smtpConfig == null)
         {
-            return DeliveryOutcome.Permanent("no SMTP configuration available");
+            return DeliveryOutcome.Permanent("No SMTP configuration available");
         }
 
         // An unknown TLS mode is a configuration error that retrying cannot fix —
@@ -146,7 +146,7 @@ public sealed class EmailNotificationDeliveryAdapter : INotificationDeliveryAdap
             _logger.LogError(
                 "Unclassified failure delivering email to list '{List}' ({ExceptionType}): {Detail}",
                 notification.ListName, ex.GetType().Name, detail);
-            return DeliveryOutcome.Permanent($"email delivery failed: {detail}");
+            return DeliveryOutcome.Permanent($"Email delivery failed: {detail}");
         }
     }
 
@@ -227,7 +227,7 @@ public sealed class EmailNotificationDeliveryAdapter : INotificationDeliveryAdap
     {
         if (!MailboxAddress.TryParse(fromAddress, out _))
         {
-            return $"invalid sender (from) email address: '{fromAddress}'";
+            return $"Invalid sender (from) email address: '{fromAddress}'";
         }
 
         var invalid = recipients
@@ -236,7 +236,7 @@ public sealed class EmailNotificationDeliveryAdapter : INotificationDeliveryAdap
             .ToList();
 
         return invalid.Count > 0
-            ? $"invalid recipient email address(es): {string.Join(", ", invalid)}"
+            ? $"Invalid recipient email address(es): {string.Join(", ", invalid)}"
             : null;
     }
 

tests/ScadaLink.NotificationOutbox.Tests/Delivery/EmailNotificationDeliveryAdapterTests.cs

@@ -188,4 +188,80 @@ public class EmailNotificationDeliveryAdapterTests
 
         Assert.Equal(DeliveryResult.TransientFailure, outcome.Result);
     }
+
+    [Fact]
+    public async Task Deliver_UnclassifiedException_ReturnsPermanent()
+    {
+        SetupHappyPath();
+        _smtpClient
+            .SendAsync(Arg.Any<string>(), Arg.Any<IEnumerable<string>>(),
+                Arg.Any<string>(), Arg.Any<string>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new InvalidOperationException("token endpoint unreachable"));
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.NotNull(outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_MalformedRecipientAddress_ReturnsPermanent()
+    {
+        const string malformed = "bad-recipient@";
+        var list = new NotificationList("ops-team") { Id = 1 };
+        _repository.GetListByNameAsync("ops-team").Returns(list);
+        _repository.GetRecipientsByListIdAsync(1).Returns(new List<NotificationRecipient>
+        {
+            new("Mallory", malformed) { Id = 1, NotificationListId = 1 }
+        });
+        _repository.GetAllSmtpConfigurationsAsync().Returns(new List<SmtpConfiguration>
+        {
+            new("smtp.example.com", "basic", "noreply@example.com")
+            {
+                Id = 1, Port = 587, Credentials = "user:pass", TlsMode = "starttls"
+            }
+        });
+        var adapter = CreateAdapter();
+
+        var outcome = await adapter.DeliverAsync(MakeNotification());
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Contains(malformed, outcome.Error);
+    }
+
+    [Fact]
+    public async Task Deliver_CancelledToken_ThrowsOperationCanceledException()
+    {
+        using var cts = new CancellationTokenSource();
+        cts.Cancel();
+
+        // List/recipient/SMTP-config resolution must succeed for any token so that
+        // delivery proceeds far enough to observe the cancellation at the SMTP call.
+        var list = new NotificationList("ops-team") { Id = 1 };
+        _repository.GetListByNameAsync("ops-team", Arg.Any<CancellationToken>()).Returns(list);
+        _repository.GetRecipientsByListIdAsync(1, Arg.Any<CancellationToken>())
+            .Returns(new List<NotificationRecipient>
+            {
+                new("Alice", "alice@example.com") { Id = 1, NotificationListId = 1 }
+            });
+        _repository.GetAllSmtpConfigurationsAsync(Arg.Any<CancellationToken>())
+            .Returns(new List<SmtpConfiguration>
+            {
+                new("smtp.example.com", "basic", "noreply@example.com")
+                {
+                    Id = 1, Port = 587, Credentials = "user:pass", TlsMode = "starttls"
+                }
+            });
+
+        // The connect call honours the cancelled token, mirroring a real SMTP client.
+        _smtpClient
+            .ConnectAsync(Arg.Any<string>(), Arg.Any<int>(), Arg.Any<SmtpTlsMode>(),
+                Arg.Any<int>(), Arg.Any<CancellationToken>())
+            .ThrowsAsync(new OperationCanceledException(cts.Token));
+        var adapter = CreateAdapter();
+
+        await Assert.ThrowsAnyAsync<OperationCanceledException>(
+            () => adapter.DeliverAsync(MakeNotification(), cts.Token));
+    }
 }