nom_language::error::convert_error panics with too long of an input #1871
Description
use nom_language::error::{VerboseError, VerboseErrorKind};
fn main() {
let input = "x".repeat(u16::MAX as usize);
let input_str = input.as_str();
let error_location = &input_str[u16::MAX as usize..];
// // Doesn't panic
// let error_location = &input_str[u16::MAX as usize - 1..];
// Construct the error as nom would
let error = VerboseError {
errors: vec![(
error_location,
VerboseErrorKind::Nom(nom::error::ErrorKind::Tag),
)],
};
// This will panic!
// nom-language calculates: column_number = line.offset(substring) + 1 = 199001
// Then tries: `write!(&mut result, "{caret:>column$}", caret='^', column=199001)` in nom-language/src/error.rs
// Formatter cannot allocate 199001 spaces and panics
nom_language::error::convert_error(input_str, error);
}Running outputs:
thread 'main' (17897756) panicked at ~/.local/share/cargo/registry/src/index.crates.io-1949cf8c6b5b557f/nom-language-0.1.0/src/error.rs:210:37:
Formatting argument out of range
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
I think the solution here is to break/change implementation of convert_error to truncate the output to only the first and last X (maybe 1k?) characters. I don't think anyone needs to see >10k chars printed to the console or even saved to a file under any circumstance