JetBrains Rider 2021.2 Help

Code Inspection: Collection is never updated (private accessibility)

JetBrains Rider analyzes access to collections created in your code and warns you if a collection is never filled or modified even if there is read access to this collection. For example:

public void Bar() { var col = new List<string>(); Console.WriteLine(col[0]); }

All standard collection types are analyzed this way by default. If necessary, you can also apply this analysis to your custom collections that derive from IEnumerable. In this case, you need to tell JetBrains Rider how invocations of collection’s public methods will affect the contents of the collection. To do so, mark the methods of your collection class with the [CollectionAccessAttribute], which should have one of four flags: None, Read, ModifyExisitingContent, UpdatedContent (the difference between the last two flags is that UpdatedContent means that the marked function can also add new elements to the collection). Here is a simple example to illustrate this:

Using JetBrains Rider code annotation to improve code analysis of collection access
Last modified: 08 March 2021