select! when returning an error gives an empty expected

[ManicMarrc]

Whenever the select! parser returns an ExpectedFound error, it makes the expected field empty.
I think this has to do with tokens that contains values like:

enum Token {
    Integer(u64),
    ...
}

[zesterer]

Yep, this is because chumsky has no way of understanding what select! is trying to expect. Right now, an empty expected field should be interpreted as 'something else'. If you want to give it a particular value, I recommend using .labelled(...), which allows you to annotate parser patterns with explicit labels and have them appear in the expected list (for example, 'expected expression').

In the future we're planning to add more ways to automatically produce better error information.