utf8.rs 1.02 KiB
use encoding_rs::{DecoderResult, UTF_8};
pub fn validate<I: Iterator<Item = u8>>(iter: I) -> bool {
let mut decoder = UTF_8.new_decoder();
let mut dest = [0; 4];
for b in iter {
let (status, _, _) = decoder.decode_to_utf8_without_replacement(&[b], &mut dest, false);
if !valid_result(status) {
return false;
}
}
let (status, _, _) = decoder.decode_to_utf8_without_replacement(&[], &mut dest, true);
valid_result(status)
}
fn valid_result(result: DecoderResult) -> bool {
match result {
DecoderResult::InputEmpty => true,
DecoderResult::OutputFull => unreachable!(),
DecoderResult::Malformed(_, _) => false,
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn validate_valid() {
let valid = b"I am valid\xf0\x90\x8c\xbc";
assert!(validate(valid.iter().cloned()));
}
#[test]
fn validate_invalid() {
let invalid = b"I am invalid\xc3\x28";
assert!(!validate(invalid.iter().cloned()));
}
}