use std::io::Write; use gix::{bstr::BStr, utils::AsBStr}; /// Write arbitrary bytes losslessly, quoting the entire value with its debug representation if it contains/// control characters, quotes, backslashes, or invalid UTF-8 that must be escaped.pub(crate) fn write_bstr(mut out: impl Write, input: &BStr, scratch: &mut Vec<u8>) -> std::io::Result<()> { scratch.clear(); write!(scratch, "{input:?}").expect("writing to a byte buffer cannot fail"); let debug_matches_input = scratch .strip_prefix(b"\"") .and_then(|debug| debug.strip_suffix(b"\"")) .is_some_and(|debug| debug == input); let input = if debug_matches_input { input } else { scratch.as_bstr() }; out.write_all(input)} #[cfg(test)]mod tests { use gix::bstr::ByteSlice; use super::write_bstr; fn render(input: &[u8], scratch: &mut Vec<u8>) -> Vec<u8> { let mut out = Vec::new(); write_bstr(&mut out, input.as_bstr(), scratch).expect("in-memory writes succeed"); out } #[test] fn safe_ascii_and_unicode_remain_unchanged() { let mut scratch = Vec::new(); for input in [b"hello world".as_slice(), "hello 💡".as_bytes()] { assert_eq!( render(input, &mut scratch), input, "safe text should remain easy to read" ); } } #[test] fn terminal_controls_and_ambiguous_bytes_are_quoted_losslessly() { let mut scratch = Vec::new(); assert_eq!( render(b"control-\0\x08\t\n\r\x1b\x7f\"\\end", &mut scratch), br#""control-\0\x08\t\n\r\x1b\x7f\"\\end""#, "terminal-active and syntax bytes must be escaped" ); assert_eq!( render(b"invalid-\xff", &mut scratch), br#""invalid-\xff""#, "invalid UTF-8 must remain recoverable" ); }}
use std::io::Write;
use gix::{bstr::BStr, utils::AsBStr};
/// Write arbitrary bytes losslessly, quoting the entire value with its debug representation if it contains
/// control characters, quotes, backslashes, or invalid UTF-8 that must be escaped.
pub(crate) fn write_bstr(mut out: impl Write, input: &BStr, scratch: &mut Vec<u8>) -> std::io::Result<()> {
scratch.clear();
write!(scratch, "{input:?}").expect("writing to a byte buffer cannot fail");
let debug_matches_input = scratch
.strip_prefix(b"\"")
.and_then(|debug| debug.strip_suffix(b"\""))
.is_some_and(|debug| debug == input);
let input = if debug_matches_input { input } else { scratch.as_bstr() };
out.write_all(input)
}
#[cfg(test)]
mod tests {
use gix::bstr::ByteSlice;
use super::write_bstr;
fn render(input: &[u8], scratch: &mut Vec<u8>) -> Vec<u8> {
let mut out = Vec::new();
write_bstr(&mut out, input.as_bstr(), scratch).expect("in-memory writes succeed");
out
}
#[test]
fn safe_ascii_and_unicode_remain_unchanged() {
let mut scratch = Vec::new();
for input in [b"hello world".as_slice(), "hello 💡".as_bytes()] {
assert_eq!(
render(input, &mut scratch),
input,
"safe text should remain easy to read"
);
}
}
#[test]
fn terminal_controls_and_ambiguous_bytes_are_quoted_losslessly() {
let mut scratch = Vec::new();
assert_eq!(
render(b"control-\0\x08\t\n\r\x1b\x7f\"\\end", &mut scratch),
br#""control-\0\x08\t\n\r\x1b\x7f\"\\end""#,
"terminal-active and syntax bytes must be escaped"
);
assert_eq!(
render(b"invalid-\xff", &mut scratch),
br#""invalid-\xff""#,
"invalid UTF-8 must remain recoverable"
);
}
}