try_map error changing spans if used with padded_by #918
Description
Hi,
I am facing an issue where a custom error I throw in a try_map (with the correct span) has the span changed when used with padded_by.
Here is an example:
use chumsky::prelude::*;
fn main() {
let errors = parser().parse("onetwo").into_errors();
println!("{:?}", errors);
}
pub fn parser<'src>() -> impl Parser<'src, &'src str, (), extra::Err<Rich<'src, char>>> {
just("one")
.padded_by(text::whitespace())
.then(
just("two")
.try_map(|val, span| {
if val == "two" {
Err(Rich::custom(span, "uh oh"))
} else {
Ok(val)
}
})
.map_err(|error| {
println!("err1 {:?}", error);
error
}),
)
.map_err(|error| {
println!("err2 {:?}", error);
error
})
.ignored()
}This will print the following:
err1 uh oh at 3..6
err2 uh oh at 3..4
[uh oh at 3..4]
Notice how the original span (3..6) is converted to 3..4.
If I remove the line .padded_by(text::whitespace()), or I change it to .padded(), then I get the correct spans:
err1 uh oh at 3..6
err2 uh oh at 3..6
[uh oh at 3..6]
I can't tell if I'm doing something wrong, or if this is a bug.
I am using Chumsky v0.11.2