bytes_expand/buf/
vec_deque.rs

1use std::collections::VecDeque;
2
3use super::Buf;
4
5impl Buf for VecDeque<u8> {
6    fn remaining(&self) -> usize {
7        self.len()
8    }
9
10    fn bytes(&self) -> &[u8] {
11        let (s1, s2) = self.as_slices();
12        if s1.is_empty() {
13            s2
14        } else {
15            s1
16        }
17    }
18
19    fn advance(&mut self, cnt: usize) {
20        self.drain(..cnt);
21    }
22}
23
24#[cfg(test)]
25mod tests {
26    use super::*;
27
28    #[test]
29    fn hello_world() {
30        let mut buffer: VecDeque<u8> = VecDeque::new();
31        buffer.extend(b"hello world");
32        assert_eq!(11, buffer.remaining());
33        assert_eq!(b"hello world", buffer.bytes());
34        buffer.advance(6);
35        assert_eq!(b"world", buffer.bytes());
36        buffer.extend(b" piece");
37        assert_eq!(b"world piece" as &[u8], &buffer.collect::<Vec<u8>>()[..]);
38    }
39}