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#[derive(Debug)]
pub struct Error {
message: String
}
impl std::error::Error for Error {}
unsafe impl Send for Error {}
unsafe impl Sync for Error {}
impl Error {
pub(crate) fn new(message: &str) -> Error {
Error {
message: String::from(message),
}
}
pub(crate) fn from_remain(remain: &str) -> Error {
Error {
message: format_error_message(remain)
}
}
pub fn message(&self) -> &String {
&self.message
}
}
impl std::fmt::Display for Error {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", self.message)
}
}
fn format_error_message(remain: &str) -> String {
let invalid: &str;
if remain.len() >= 3 {
invalid = &remain[..3];
} else {
invalid = &remain[..remain.len()];
}
return format!("invalid sequence: \"{}\"", invalid).to_lowercase();
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn message_format() {
assert_eq!(format_error_message("abcdefg"),"invalid sequence: \"abc\"");
assert_eq!(format_error_message("abc"),"invalid sequence: \"abc\"");
assert_eq!(format_error_message("ab"),"invalid sequence: \"ab\"");
assert_eq!(format_error_message("a"),"invalid sequence: \"a\"");
}
}