| #![allow(dead_code)] |
| |
| use crate::fmt::{Formatter, Result, Write}; |
| use core::str::lossy::{Utf8Lossy, Utf8LossyChunk}; |
| |
| pub fn debug_fmt_bytestring(slice: &[u8], f: &mut Formatter<'_>) -> Result { |
| // Writes out a valid unicode string with the correct escape sequences |
| fn write_str_escaped(f: &mut Formatter<'_>, s: &str) -> Result { |
| for c in s.chars().flat_map(|c| c.escape_debug()) { |
| f.write_char(c)? |
| } |
| Ok(()) |
| } |
| |
| f.write_str("\"")?; |
| for Utf8LossyChunk { valid, broken } in Utf8Lossy::from_bytes(slice).chunks() { |
| write_str_escaped(f, valid)?; |
| for b in broken { |
| write!(f, "\\x{:02X}", b)?; |
| } |
| } |
| f.write_str("\"") |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use super::*; |
| use crate::fmt::{Debug, Formatter, Result}; |
| |
| #[test] |
| fn smoke() { |
| struct Helper<'a>(&'a [u8]); |
| |
| impl Debug for Helper<'_> { |
| fn fmt(&self, f: &mut Formatter<'_>) -> Result { |
| debug_fmt_bytestring(self.0, f) |
| } |
| } |
| |
| let input = b"\xF0hello,\tworld"; |
| let expected = r#""\xF0hello,\tworld""#; |
| let output = format!("{:?}", Helper(input)); |
| |
| assert!(output == expected); |
| } |
| } |