From 5bb655e3f6d3acc6963054f9517c8cd5257c522b Mon Sep 17 00:00:00 2001
From: Jordan Dominion <Cyberboss@users.noreply.github.com>
Date: Sat, 21 Oct 2023 18:48:14 -0400
Subject: [PATCH] Add test for hard links

---
 .../IO/TestFilesystemLinkFactory.cs           | 57 ++++++++++++++++++-
 1 file changed, 55 insertions(+), 2 deletions(-)

diff --git a/tests/Tgstation.Server.Host.Tests/IO/TestFilesystemLinkFactory.cs b/tests/Tgstation.Server.Host.Tests/IO/TestFilesystemLinkFactory.cs
index e735c48541..dbf2aaf2a8 100644
--- a/tests/Tgstation.Server.Host.Tests/IO/TestFilesystemLinkFactory.cs
+++ b/tests/Tgstation.Server.Host.Tests/IO/TestFilesystemLinkFactory.cs
@@ -1,10 +1,12 @@
-using Microsoft.VisualStudio.TestTools.UnitTesting;
-using System;
+using System;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Security.Principal;
+using System.Threading;
 using System.Threading.Tasks;
 
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
 namespace Tgstation.Server.Host.IO.Tests
 {
 	[TestClass]
@@ -30,6 +32,57 @@ namespace Tgstation.Server.Host.IO.Tests
 			return principal.IsInRole(WindowsBuiltInRole.Administrator);
 		}
 
+		[TestMethod]
+		public async Task TestHardLinkWorks()
+		{
+			string f2 = null;
+			var f1 = Path.GetTempFileName();
+			try
+			{
+				f2 = f1 + ".linked";
+				const string Text = "Hello world";
+				File.WriteAllText(f1, Text);
+
+				if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+				{
+					await Assert.ThrowsExceptionAsync<NotSupportedException>(() => linkFactory.CreateHardLink(f1, f2, CancellationToken.None));
+					Assert.Inconclusive("Windows does not support hardlinks");
+				}
+
+				await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => linkFactory.CreateHardLink(null, null, CancellationToken.None));
+				await Assert.ThrowsExceptionAsync<ArgumentNullException>(() => linkFactory.CreateHardLink(f1, null, CancellationToken.None));
+
+				await linkFactory.CreateHardLink(f1, f2, default);
+				Assert.IsTrue(File.Exists(f2));
+
+				var f2Contents = File.ReadAllText(f2);
+				Assert.AreEqual(Text, f2Contents);
+
+				const string NewText = "asdf";
+				File.WriteAllText(f1, NewText);
+
+				f2Contents = File.ReadAllText(f2);
+				Assert.AreEqual(NewText, f2Contents);
+
+				const string NewText2 = "fdsa";
+				File.WriteAllText(f2, NewText2);
+
+				var f1Contents = File.ReadAllText(f1);
+				Assert.AreEqual(NewText2, f1Contents);
+
+				File.Delete(f1);
+				Assert.IsFalse(File.Exists(f1));
+				Assert.IsTrue(File.Exists(f2));
+				f2Contents = File.ReadAllText(f2);
+				Assert.AreEqual(NewText2, f2Contents);
+			}
+			finally
+			{
+				File.Delete(f2);
+				File.Delete(f1);
+			}
+		}
+
 		[TestMethod]
 		public async Task TestFileWorks()
 		{