Why is this an issue?

Marking a method with the Pure attribute indicates that the method doesn’t make any visible state changes. Therefore, a Pure method should return a result otherwise it indicates a no-operation call.

Using Pure on a void method is either by mistake or the method is not doing a meaningful task.

How to fix it

Code examples

Noncompliant code example

class Person
{
  private int age;

  [Pure] // Noncompliant: The method makes a state change
  void ConfigureAge(int age) =>
    this.age = age;
}

Compliant solution

class Person
{
  private int age;

  void ConfigureAge(int age) =>
    this.age = age;
}

Resources

Documentation

• Microsoft Learn - PureAttribute Class