use std::borrow::{Borrow, Cow};
use no_std_io::io::{Read, Write};
use crate::reader::Reader;
use crate::writer::Writer;
use crate::{DekuError, DekuReader, DekuWriter};
impl<'a, T, Ctx> DekuReader<'a, Ctx> for Cow<'a, T>
where
T: DekuReader<'a, Ctx> + Clone,
Ctx: Copy,
{
fn from_reader_with_ctx<R: Read>(
reader: &mut Reader<R>,
inner_ctx: Ctx,
) -> Result<Self, DekuError> {
let val = <T>::from_reader_with_ctx(reader, inner_ctx)?;
Ok(Cow::Owned(val))
}
}
impl<T, Ctx> DekuWriter<Ctx> for Cow<'_, T>
where
T: DekuWriter<Ctx> + Clone,
Ctx: Copy,
{
fn to_writer<W: Write>(&self, writer: &mut Writer<W>, inner_ctx: Ctx) -> Result<(), DekuError> {
(self.borrow() as &T).to_writer(writer, inner_ctx)
}
}
#[cfg(test)]
mod tests {
use no_std_io::io::Cursor;
use rstest::rstest;
use super::*;
use crate::{native_endian, reader::Reader};
#[rstest(input, expected,
case(
&[0xEF, 0xBE],
Cow::Owned(native_endian!(0xBEEF_u16)),
),
)]
fn test_cow(input: &[u8], expected: Cow<u16>) {
let mut cursor = Cursor::new(input);
let mut reader = Reader::new(&mut cursor);
let res_read = <Cow<u16>>::from_reader_with_ctx(&mut reader, ()).unwrap();
assert_eq!(expected, res_read);
let mut writer = Writer::new(vec![]);
res_read.to_writer(&mut writer, ()).unwrap();
assert_eq!(input.to_vec(), writer.inner);
}
}