diff --git a/Emby.Naming/Video/CleanStringParser.cs b/Emby.Naming/Video/CleanStringParser.cs
index bd7553a91..4eef3ebc5 100644
--- a/Emby.Naming/Video/CleanStringParser.cs
+++ b/Emby.Naming/Video/CleanStringParser.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Text.RegularExpressions;
 
 namespace Emby.Naming.Video
@@ -16,8 +17,14 @@ namespace Emby.Naming.Video
         /// <param name="expressions">List of regex to parse name and year from.</param>
         /// <param name="newName">Parsing result string.</param>
         /// <returns>True if parsing was successful.</returns>
-        public static bool TryClean(string name, IReadOnlyList<Regex> expressions, out ReadOnlySpan<char> newName)
+        public static bool TryClean([NotNullWhen(true)] string? name, IReadOnlyList<Regex> expressions, out ReadOnlySpan<char> newName)
         {
+            if (string.IsNullOrEmpty(name))
+            {
+                newName = ReadOnlySpan<char>.Empty;
+                return false;
+            }
+
             var len = expressions.Count;
             for (int i = 0; i < len; i++)
             {
@@ -33,12 +40,6 @@ namespace Emby.Naming.Video
 
         private static bool TryClean(string name, Regex expression, out ReadOnlySpan<char> newName)
         {
-            if (string.IsNullOrEmpty(name))
-            {
-                newName = ReadOnlySpan<char>.Empty;
-                return false;
-            }
-
             var match = expression.Match(name);
             int index = match.Index;
             if (match.Success && index != 0)
diff --git a/Emby.Naming/Video/VideoResolver.cs b/Emby.Naming/Video/VideoResolver.cs
index 619d1520e..79a6da8f7 100644
--- a/Emby.Naming/Video/VideoResolver.cs
+++ b/Emby.Naming/Video/VideoResolver.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using Emby.Naming.Common;
@@ -146,7 +147,7 @@ namespace Emby.Naming.Video
         /// <param name="name">Raw name.</param>
         /// <param name="newName">Clean name.</param>
         /// <returns>True if cleaning of name was successful.</returns>
-        public bool TryCleanString(string name, out ReadOnlySpan<char> newName)
+        public bool TryCleanString([NotNullWhen(true)] string? name, out ReadOnlySpan<char> newName)
         {
             return CleanStringParser.TryClean(name, _options.CleanStringRegexes, out newName);
         }
diff --git a/Emby.Server.Implementations/Library/PathExtensions.cs b/Emby.Server.Implementations/Library/PathExtensions.cs
index 7dcc925c2..57d0c26b9 100644
--- a/Emby.Server.Implementations/Library/PathExtensions.cs
+++ b/Emby.Server.Implementations/Library/PathExtensions.cs
@@ -59,11 +59,18 @@ namespace Emby.Server.Implementations.Library
         /// <param name="newPath">The result of the sub path replacement</param>
         /// <returns>The path after replacing the sub path.</returns>
         /// <exception cref="ArgumentNullException"><paramref name="path" />, <paramref name="newSubPath" /> or <paramref name="newSubPath" /> is empty.</exception>
-        public static bool TryReplaceSubPath(this string path, string subPath, string newSubPath, [NotNullWhen(true)] out string? newPath)
+        public static bool TryReplaceSubPath(
+            [NotNullWhen(true)] this string? path,
+            [NotNullWhen(true)] string? subPath,
+            [NotNullWhen(true)] string? newSubPath,
+            [NotNullWhen(true)] out string? newPath)
         {
             newPath = null;
 
-            if (string.IsNullOrEmpty(path) || string.IsNullOrEmpty(subPath) || string.IsNullOrEmpty(newSubPath) || subPath.Length > path.Length)
+            if (string.IsNullOrEmpty(path)
+                || string.IsNullOrEmpty(subPath)
+                || string.IsNullOrEmpty(newSubPath)
+                || subPath.Length > path.Length)
             {
                 return false;
             }
diff --git a/tests/Jellyfin.Naming.Tests/Video/CleanStringTests.cs b/tests/Jellyfin.Naming.Tests/Video/CleanStringTests.cs
index 4b363843a..a720bdade 100644
--- a/tests/Jellyfin.Naming.Tests/Video/CleanStringTests.cs
+++ b/tests/Jellyfin.Naming.Tests/Video/CleanStringTests.cs
@@ -7,18 +7,13 @@ namespace Jellyfin.Naming.Tests.Video
 {
     public sealed class CleanStringTests
     {
-        private readonly NamingOptions _namingOptions = new NamingOptions();
+        private readonly VideoResolver _videoResolver = new VideoResolver(new NamingOptions());
 
         [Theory]
         [InlineData("Super movie 480p.mp4", "Super movie")]
         [InlineData("Super movie 480p 2001.mp4", "Super movie")]
         [InlineData("Super movie [480p].mp4", "Super movie")]
         [InlineData("480 Super movie [tmdbid=12345].mp4", "480 Super movie")]
-        [InlineData("Super movie(2009).mp4", "Super movie(2009).mp4")]
-        [InlineData("Run lola run (lola rennt) (2009).mp4", "Run lola run (lola rennt) (2009).mp4")]
-        [InlineData(@"American.Psycho.mkv", "American.Psycho.mkv")]
-        [InlineData(@"American Psycho.mkv", "American Psycho.mkv")]
-        [InlineData(@"[rec].mkv", "[rec].mkv")]
         [InlineData("Crouching.Tiger.Hidden.Dragon.4k.mkv", "Crouching.Tiger.Hidden.Dragon")]
         [InlineData("Crouching.Tiger.Hidden.Dragon.UltraHD.mkv", "Crouching.Tiger.Hidden.Dragon")]
         [InlineData("Crouching.Tiger.Hidden.Dragon.UHD.mkv", "Crouching.Tiger.Hidden.Dragon")]
@@ -28,19 +23,26 @@ namespace Jellyfin.Naming.Tests.Video
         [InlineData("Crouching.Tiger.Hidden.Dragon.BDrip.mkv", "Crouching.Tiger.Hidden.Dragon")]
         [InlineData("Crouching.Tiger.Hidden.Dragon.BDrip-HDC.mkv", "Crouching.Tiger.Hidden.Dragon")]
         [InlineData("Crouching.Tiger.Hidden.Dragon.4K.UltraHD.HDR.BDrip-HDC.mkv", "Crouching.Tiger.Hidden.Dragon")]
-        [InlineData(null, null)]
         // FIXME: [InlineData("After The Sunset - [0004].mkv", "After The Sunset")]
-        public void CleanStringTest(string input, string expectedName)
+        public void CleanStringTest_NeedsCleaning_Success(string input, string expectedName)
         {
-            if (new VideoResolver(_namingOptions).TryCleanString(input, out ReadOnlySpan<char> newName))
-            {
-                // TODO: compare spans when XUnit supports it
-                Assert.Equal(expectedName, newName.ToString());
-            }
-            else
-            {
-                Assert.Equal(expectedName, input);
-            }
+            Assert.True(_videoResolver.TryCleanString(input, out ReadOnlySpan<char> newName));
+            // TODO: compare spans when XUnit supports it
+            Assert.Equal(expectedName, newName.ToString());
+        }
+
+        [Theory]
+        [InlineData(null)]
+        [InlineData("")]
+        [InlineData("Super movie(2009).mp4")]
+        [InlineData("[rec].mkv")]
+        [InlineData("American.Psycho.mkv")]
+        [InlineData("American Psycho.mkv")]
+        [InlineData("Run lola run (lola rennt) (2009).mp4")]
+        public void CleanStringTest_DoesntNeedCleaning_False(string? input)
+        {
+            Assert.False(_videoResolver.TryCleanString(input, out ReadOnlySpan<char> newName));
+            Assert.True(newName.IsEmpty);
         }
     }
 }
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/PathExtensionsTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/PathExtensionsTests.cs
index a6fe90566..e5508243f 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Library/PathExtensionsTests.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/PathExtensionsTests.cs
@@ -40,12 +40,16 @@ namespace Jellyfin.Server.Implementations.Tests.Library
         }
 
         [Theory]
+        [InlineData(null, null, null)]
+        [InlineData(null, "/my/path", "/another/path")]
+        [InlineData("/my/path", null, "/another/path")]
+        [InlineData("/my/path", "/another/path", null)]
         [InlineData("", "", "")]
         [InlineData("/my/path", "", "")]
         [InlineData("", "/another/path", "")]
         [InlineData("", "", "/new/subpath")]
         [InlineData("/home/jeff/music/jeff's band/consistently inconsistent.mp3", "/home/jeff/music/not jeff's band", "/home/not jeff")]
-        public void TryReplaceSubPath_InvalidInput_ReturnsFalseAndNull(string path, string subPath, string newSubPath)
+        public void TryReplaceSubPath_InvalidInput_ReturnsFalseAndNull(string? path, string? subPath, string? newSubPath)
         {
             Assert.False(PathExtensions.TryReplaceSubPath(path, subPath, newSubPath, out var result));
             Assert.Null(result);