Code inspection: 'void' method is annotated with the [Pure] attribute

This inspection reports void methods annotated with [Pure]. A pure method is expected to return a value that depends only on its inputs and has no observable side effects. A void method cannot return such a value, so the annotation is usually misleading.

Example

                using JetBrains.Annotations;
                class C
                {
                    [Pure]
                    public void UpdateState()
                    {
                    }
                }
            

                class C
                {
                    [Pure]
                    public int GetState()
                    {
                        return 42;
                    }
                }
            

Quick-fix

Remove the attribute, or change the method so it returns the computed value instead of being void.

01 April 2026