musli_zerocopy/
lossy_str.rs

1use core::fmt;
2use core::str;
3
4#[repr(transparent)]
5pub(crate) struct LossyStr([u8]);
6
7impl LossyStr {
8    /// Construct a new lossy string.
9    pub(crate) fn new<S>(bytes: &S) -> &Self
10    where
11        S: ?Sized + AsRef<[u8]>,
12    {
13        // SAFETY: LossyStr is repr transparent over [u8].
14        unsafe { &*(bytes.as_ref() as *const [u8] as *const LossyStr) }
15    }
16}
17
18impl fmt::Debug for LossyStr {
19    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
20        let mut bytes = &self.0;
21
22        write!(f, "\"")?;
23
24        loop {
25            let (string, replacement) = match str::from_utf8(bytes) {
26                Ok(s) => (s, false),
27                Err(e) => {
28                    let (valid, invalid) = bytes.split_at(e.valid_up_to());
29                    bytes = invalid.get(1..).unwrap_or_default();
30                    (unsafe { str::from_utf8_unchecked(valid) }, true)
31                }
32            };
33
34            for c in string.chars() {
35                match c {
36                    '\0' => write!(f, "\\0")?,
37                    '\x01'..='\x08' | '\x0b' | '\x0c' | '\x0e'..='\x19' | '\x7f' => {
38                        write!(f, "\\x{:02x}", c as u32)?;
39                    }
40                    _ => {
41                        write!(f, "{}", c.escape_debug())?;
42                    }
43                }
44            }
45
46            if !replacement {
47                break;
48            }
49
50            write!(f, "\u{FFFD}")?;
51        }
52
53        write!(f, "\"")?;
54        Ok(())
55    }
56}
musli_zerocopy/lossy_str.rs

musli_zerocopy/
lossy_str.rs
