1 files changed, 18 insertions, 14 deletions

diff --git a/Emby.Server.Implementations/Collections/CollectionManager.cs b/Emby.Server.Implementations/Collections/CollectionManager.cs
index 187e0c9b3..179683055 100644
--- a/Emby.Server.Implementations/Collections/CollectionManager.cs
+++ b/Emby.Server.Implementations/Collections/CollectionManager.cs
@@ -81,7 +81,7 @@ namespace Emby.Server.Implementations.Collections
         internal async Task<Folder?> EnsureLibraryFolder(string path, bool createIfNeeded)
         {
             var existingFolder = FindFolders(path).FirstOrDefault();
-            if (existingFolder != null)
+            if (existingFolder is not null)
             {
                 return existingFolder;
             }
@@ -121,7 +121,7 @@ namespace Emby.Server.Implementations.Collections
         {
             var folder = GetCollectionsFolder(false).GetAwaiter().GetResult();
 
-            return folder == null
+            return folder is null
                 ? Enumerable.Empty<BoxSet>()
                 : folder.GetChildren(user, true).OfType<BoxSet>();
         }
@@ -138,7 +138,7 @@ namespace Emby.Server.Implementations.Collections
 
             var parentFolder = await GetCollectionsFolder(true).ConfigureAwait(false);
 
-            if (parentFolder == null)
+            if (parentFolder is null)
             {
                 throw new ArgumentException(nameof(parentFolder));
             }
@@ -206,8 +206,7 @@ namespace Emby.Server.Implementations.Collections
                 throw new ArgumentException("No collection exists with the supplied Id");
             }
 
-            var list = new List<LinkedChild>();
-            var itemList = new List<BaseItem>();
+            List<BaseItem>? itemList = null;
 
             var linkedChildrenList = collection.GetLinkedChildren();
             var currentLinkedChildrenIds = linkedChildrenList.Select(i => i.Id).ToList();
@@ -216,25 +215,30 @@ namespace Emby.Server.Implementations.Collections
             {
                 var item = _libraryManager.GetItemById(id);
 
-                if (item == null)
+                if (item is null)
                 {
                     throw new ArgumentException("No item exists with the supplied Id");
                 }
 
                 if (!currentLinkedChildrenIds.Contains(id))
                 {
-                    itemList.Add(item);
+                    (itemList ??= new()).Add(item);
 
-                    list.Add(LinkedChild.Create(item));
                     linkedChildrenList.Add(item);
                 }
             }
 
-            if (list.Count > 0)
+            if (itemList is not null)
             {
-                LinkedChild[] newChildren = new LinkedChild[collection.LinkedChildren.Length + list.Count];
+                var originalLen = collection.LinkedChildren.Length;
+                var newItemCount = itemList.Count;
+                LinkedChild[] newChildren = new LinkedChild[originalLen + newItemCount];
                 collection.LinkedChildren.CopyTo(newChildren, 0);
-                list.CopyTo(newChildren, collection.LinkedChildren.Length);
+                for (int i = 0; i < newItemCount; i++)
+                {
+                    newChildren[originalLen + i] = LinkedChild.Create(itemList[i]);
+                }
+
                 collection.LinkedChildren = newChildren;
                 collection.UpdateRatingToItems(linkedChildrenList);
 
@@ -265,9 +269,9 @@ namespace Emby.Server.Implementations.Collections
             {
                 var childItem = _libraryManager.GetItemById(guidId);
 
-                var child = collection.LinkedChildren.FirstOrDefault(i => (i.ItemId.HasValue && i.ItemId.Value.Equals(guidId)) || (childItem != null && string.Equals(childItem.Path, i.Path, StringComparison.OrdinalIgnoreCase)));
+                var child = collection.LinkedChildren.FirstOrDefault(i => (i.ItemId.HasValue && i.ItemId.Value.Equals(guidId)) || (childItem is not null && string.Equals(childItem.Path, i.Path, StringComparison.OrdinalIgnoreCase)));
 
-                if (child == null)
+                if (child is null)
                 {
                     _logger.LogWarning("No collection title exists with the supplied Id");
                     continue;
@@ -275,7 +279,7 @@ namespace Emby.Server.Implementations.Collections
 
                 list.Add(child);
 
-                if (childItem != null)
+                if (childItem is not null)
                 {
                     itemList.Add(childItem);
                 }