S3532 — Empty "default" clauses should be removed

Why is this an issue?

The default clause should take appropriate action. Having an empty default is a waste of keystrokes.

Noncompliant code example

enum Fruit
{
  Apple,
  Orange,
  Banana
}

void PrintName(Fruit fruit)
{
  switch(fruit)
  {
    case Fruit.Apple:
      Console.WriteLine("apple");
      break;
    default:  //Noncompliant
      break;
  }
}

Compliant solution

enum Fruit
{
  Apple,
  Orange,
  Banana
}

void PrintName(Fruit fruit)
{
  switch(fruit)
  {
    case Fruit.Apple:
      Console.WriteLine("apple");
      break;
    default:
      throw new NotSupportedException();
  }
}

or

void PrintName(Fruit fruit)
{
  switch(fruit)
  {
    case Fruit.Apple:
      Console.WriteLine("apple");
      break;
  }
}

Exceptions

default clauses containing only a comment are ignored with the assumption that they are empty on purpose and the comment documents why.