use core::convert::Infallible;
use qubit_codec::CapacityError;
use qubit_codec::TranscodeDecodeError;
use qubit_codec::TranscodeDecoder;
use qubit_codec::TranscodeFailure;
use qubit_codec::TranscodeProgress;
use qubit_codec::Transcoder;
#[derive(Default)]
struct ByteToChar;
impl Transcoder for ByteToChar {
type Input = u8;
type Output = char;
type Error = TranscodeDecodeError<Infallible>;
fn max_transcode_output_len(&self, input_len: usize) -> Result<usize, CapacityError> {
Ok(input_len)
}
fn reset(&mut self, output: &mut [char], output_index: usize) -> Result<usize, TranscodeDecodeError<Infallible>> {
TranscodeFailure::ensure_output_index(output.len(), output_index)?;
Ok(0)
}
fn transcode(
&mut self,
input: &[u8],
input_index: usize,
output: &mut [char],
output_index: usize,
) -> Result<TranscodeProgress, TranscodeDecodeError<Infallible>> {
let readable = input.len().saturating_sub(input_index);
let writable = output.len().saturating_sub(output_index);
let count = readable.min(writable);
for offset in 0..count {
output[output_index + offset] = input[input_index + offset] as char;
}
Ok(TranscodeProgress::complete(count, count))
}
fn finish(&mut self, output: &mut [char], output_index: usize) -> Result<usize, TranscodeDecodeError<Infallible>> {
TranscodeFailure::ensure_output_index(output.len(), output_index)?;
Ok(0)
}
}
impl TranscodeDecoder for ByteToChar {
type DecodeError = Infallible;
}
#[test]
fn test_transcode_decoder_is_a_semantic_transcoder_bound() {
fn assert_decoder<T: TranscodeDecoder<Input = u8, Output = char>>() {}
assert_decoder::<ByteToChar>();
}