diff --git a/tests/DotNetCampus.CommandLine.Tests/CommandMatching/AddHandlerTests.cs b/tests/DotNetCampus.CommandLine.Tests/CommandMatching/AddHandlerTests.cs
index 91e6a50..b8bee3b 100644
--- a/tests/DotNetCampus.CommandLine.Tests/CommandMatching/AddHandlerTests.cs
+++ b/tests/DotNetCampus.CommandLine.Tests/CommandMatching/AddHandlerTests.cs
@@ -224,6 +224,7 @@ public async Task AddHandler_TypedDelegate(string[] args, string expectedCommand
                 await Task.Yield();
                 matched = o.Value;
             })
+            .AddHandler<DefaultOptions>(_ => { })
             .RunAsync();
         var matchedTypeName = result.HandledBy!.GetType().Name;
 
@@ -232,6 +233,26 @@ public async Task AddHandler_TypedDelegate(string[] args, string expectedCommand
         Assert.AreEqual(expectedValue, matched);
     }
 
+    [TestMethod]
+    [DataRow(TestCommandLineStyle.Flexible, DisplayName = "[Flexible] foo")]
+    [DataRow(TestCommandLineStyle.DotNet, DisplayName = "[DotNet] foo")]
+    [DataRow(TestCommandLineStyle.Gnu, DisplayName = "[Gnu] foo")]
+    [DataRow(TestCommandLineStyle.Windows, DisplayName = "[Windows] foo")]
+    public void AddHandler_Discard /* 弃元 */(TestCommandLineStyle style)
+    {
+        // Arrange
+        var commandLine = CommandLine.Parse([], style.ToParsingOptions());
+
+        // Act
+        var result = commandLine
+            .AddHandler<DefaultOptions>(_ => { })
+            .Run();
+        var matchedTypeName = result.HandledBy!.GetType().Name;
+
+        // Assert
+        Assert.AreEqual(nameof(DefaultOptions), matchedTypeName);
+    }
+
     // ReSharper disable once RedundantAssignment
     private int RunWithExitCode<T>(ref T field, T value)
     {