Code inspection: Container nullability attribute usage with declaration of non-container type

This inspection reports container-item nullability annotations applied to a type that does not have nullable items.

Typical examples are [ItemNotNull] or [ItemCanBeNull] on value types or other non-container declarations. In those cases the annotation does not affect code analysis and only adds noise.

Example

In this example, the [ItemNotNull] annotation is applied to an int property. Since int is a value type and cannot be null, the annotation is redundant.

                using JetBrains.Annotations;
                public class Example
                {
                    [ItemNotNull]
                    public int RetryCount => 3;
                }
            

                using JetBrains.Annotations;
                public class Example
                {
                    public int RetryCount => 3;
                }
            

Quick-fix

The quick-fix removes the redundant container nullability annotation.

27 March 2026