Once I refactored some stringly typed C# code to use an enum with values Prod and Test instead of the two strings "Prod" and "Test". I was relying on expressio

Once I refactored some stringly typed C# code to use an enum with values Prod and Test instead of the two strings "Prod" and "Test". I was relying on expressions like mode == "Test" to fail to type-check to spot all the places that I needed to update. Sadly some parts of the codebase weren't very idiomatic and had some "Test".Equals(mode) This caused a bit of involuntary testing in production and thought me not to trust anything while refactoring.