Ensure that CommitDelayIncrement is greater than TimeSpan.Zero (#531)

* Throw argument out of range exception when CommitDelayIncrement is set to a negative value in OpenSessionOptions, and add an acceptance test to verify that an exception is thrown to the session user when CommitDelayIncrement is set to zero.

Co-authored-by: Tamara Rivera <tamita.rivera@gmail.com>

Author: hazel-bohon

src/NServiceBus.TransactionalSession.Tests/OpenSessionOptionsTests.cs

@@ -0,0 +1,34 @@
+namespace NServiceBus.TransactionalSession.Tests;
+
+using System;
+using NUnit.Framework;
+
+public class OpenSessionOptionsTests
+{
+    [Test]
+    public void Should_not_throw_exception_when_commit_delay_increment_is_greater_than_zero() =>
+        Assert.DoesNotThrow(() =>
+        {
+            var options = new CustomTestingPersistenceOpenSessionOptions
+            {
+                CommitDelayIncrement = TimeSpan.FromTicks(1),
+                MaximumCommitDuration = TimeSpan.FromSeconds(8)
+            };
+        });
+
+    [Test]
+    [TestCase(-1)]
+    [TestCase(0)]
+    public void Should_throw_exception_when_commit_delay_increment_is_less_than_or_equal_to_zero(int commitDelayIncrement) =>
+        Assert.Throws<ArgumentOutOfRangeException>(() =>
+        {
+            var options = new CustomTestingPersistenceOpenSessionOptions
+            {
+                CommitDelayIncrement = TimeSpan.FromSeconds(commitDelayIncrement),
+                MaximumCommitDuration = TimeSpan.FromSeconds(8)
+            };
+        });
+
+    class CustomTestingPersistenceOpenSessionOptions : OpenSessionOptions;
+}
+

src/NServiceBus.TransactionalSession/OpenSessionOptions.cs

@@ -37,8 +37,17 @@ public abstract class OpenSessionOptions
     /// <summary>
     /// The time increment used to delay the commit of the transactional session when the outbox record is not yet in the storage.
     /// </summary>
-    /// <remarks>Defaults to <code>TimeSpan.FromSeconds(2)</code></remarks>
-    public TimeSpan CommitDelayIncrement { get; set; } = TimeSpan.FromSeconds(2);
+    /// <remarks>Defaults to <code>TimeSpan.FromSeconds(2)</code>. Value must be greater than <code>TimeSpan.Zero</code>.</remarks>
+    public TimeSpan CommitDelayIncrement
+    {
+        get => commitDelayIncrement;
+        set
+        {
+            ArgumentOutOfRangeException.ThrowIfLessThanOrEqual(value, TimeSpan.Zero, nameof(CommitDelayIncrement));
+            commitDelayIncrement = value;
+        }
+    }
 
     Dictionary<string, string>? metadata;
+    TimeSpan commitDelayIncrement = TimeSpan.FromSeconds(2);
 }