Code Inspection: Some values of the enum are not processed inside switch expression and are handled via exception in default arm

When using a switch expression with an enum, it is not required to have arms for each enum value — these values will be processed in the _ discard.

This might be intended by the author to handle some unimportant values. But if the _ discard throws an exception, all usages of the switch with non-processed enum values will also throw the exception, which is probably a consequence of adding a new value to the enum and forgetting to update the switch accordingly.

    enum MyColor { Red, Green, Blue }

    string GetColor(MyColor color) => color switch
    {
      MyColor.Red => "Red",
      MyColor.Green => "Green",
      _ => throw new ArgumentOutOfRangeException(nameof(color))
    };

    // The value 'Blue' is not processed in the switch
    // so this call will throw an exception
    string TestColors => GetColor(MyColor.Blue);
    

Last modified: 08 March 2021