> Name suggests boolean but type does not I've seen something similar with xUnit in C# where an Assert statement returns a value. `var single = Assert.Single(c

> Name suggests boolean but type does not I've seen something similar with xUnit in C# where an Assert statement returns a value. `var single = Assert.Single(collection);` It does the assertion and returns the single item in the collection, which is awkward, but also familiar (from Linq's Single) and convenient. Here there are tradeoffs and I could care less about the dogmatic "never do this" complainers. This might break the 'Principle of Least Astonishment' the first time you see it, but after seeing it once it makes sense and is no longer surprising. Additionally, in the case of this criteria, where there is a boolean-looking function that doesn't return boolean, it can often be quickly assumed that something more than just a boolean needed to be returned. This also reminds of command-query separation which makes a lot of sense to follow in most cases ('get' shouldn't change state and state changing methods like 'save' shouldn't return a value). But there are going to be exceptions to this rule and there are scenarios where no matter if you return data or not you might need to know the HTTP status code, etc. Grabbing code and doing dogmatic research on it doesn't make a whole lot of sense unless a developer who really knows the code well can justify themselves and discuss the why.