From e713eb0b6cffd4c04f1754840b38ab1df51746fe Mon Sep 17 00:00:00 2001
From: Alex Peck <alexpeck@microsoft.com>
Date: Mon, 23 Oct 2023 11:23:42 -0700
Subject: [PATCH] unit test

---
 BitFaster.Caching.UnitTests/Lfu/LfuNodeListTests.cs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/BitFaster.Caching.UnitTests/Lfu/LfuNodeListTests.cs b/BitFaster.Caching.UnitTests/Lfu/LfuNodeListTests.cs
index e3714a85..e045a9ad 100644
--- a/BitFaster.Caching.UnitTests/Lfu/LfuNodeListTests.cs
+++ b/BitFaster.Caching.UnitTests/Lfu/LfuNodeListTests.cs
@@ -1,4 +1,5 @@
-using BitFaster.Caching.Lfu;
+using System;
+using BitFaster.Caching.Lfu;
 using FluentAssertions;
 using Xunit;
 
@@ -6,6 +7,16 @@ namespace BitFaster.Caching.UnitTests.Lfu
 {
     public class LfuNodeListTests
     {
+#if DEBUG
+        [Fact]
+        public void WhenEmptyRemoveFirstThrows()
+        {
+            var list = new LfuNodeList<int, int>();
+            Action remove = () => { list.RemoveFirst(); };
+            remove.Should().Throw<InvalidOperationException>();
+        }
+#endif
+
         [Fact]
         public void WhenPreviousNullLastReturnsNull()
         {