Skip to content

chore: use oxc_sourcemap version of escape_generic #9

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Sep 23, 2025
Merged

chore: use oxc_sourcemap version of escape_generic #9

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
133 changes: 133 additions & 0 deletions src/generic.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,133 @@
#[inline]
// Slightly modified version of
// <https://github.com/serde-rs/json/blob/d12e943590208da738c092db92c34b39796a2538/src/ser.rs#L2079>
// Borrowed from:
// <https://github.com/oxc-project/oxc-sourcemap/blob/e533e6ca4d08c538d8d4df74eacd29437851591f/src/encode.rs#L331>
pub fn escape_generic<S: AsRef<str>>(s: S) -> String {
let s = s.as_ref();
let bytes = s.as_bytes();

// Estimate capacity - most strings don't need much escaping
// Add some padding for potential escapes
let estimated_capacity = bytes.len() + bytes.len() / 2 + 2;
let mut result = Vec::with_capacity(estimated_capacity);

result.push(b'"');

let mut start = 0;
let mut i = 0;

while i < bytes.len() {
let b = bytes[i];

// Use lookup table to check if escaping is needed
let escape_byte = ESCAPE[b as usize];

if escape_byte == 0 {
// No escape needed, continue scanning
i += 1;
continue;
}

// Copy any unescaped bytes before this position
if start < i {
result.extend_from_slice(&bytes[start..i]);
}

// Handle the escape
result.push(b'\\');
if escape_byte == b'u' {
// Unicode escape for control characters
result.extend_from_slice(b"u00");
let hex_digits = &HEX_BYTES[b as usize];
result.push(hex_digits.0);
result.push(hex_digits.1);
} else {
// Simple escape
result.push(escape_byte);
}

i += 1;
start = i;
}

// Copy any remaining unescaped bytes
if start < bytes.len() {
result.extend_from_slice(&bytes[start..]);
}

result.push(b'"');

// SAFETY: We only pushed valid UTF-8 bytes (original string bytes and ASCII escape sequences)
unsafe { String::from_utf8_unchecked(result) }
}

const BB: u8 = b'b'; // \x08
const TT: u8 = b't'; // \x09
const NN: u8 = b'n'; // \x0A
const FF: u8 = b'f'; // \x0C
const RR: u8 = b'r'; // \x0D
const QU: u8 = b'"'; // \x22
const BS: u8 = b'\\'; // \x5C
pub(crate) const UU: u8 = b'u'; // \x00...\x1F except the ones above
const __: u8 = 0;

// Lookup table of escape sequences. A value of b'x' at index i means that byte
// i is escaped as "\x" in JSON. A value of 0 means that byte i is not escaped.
pub(crate) static ESCAPE: [u8; 256] = [
// 1 2 3 4 5 6 7 8 9 A B C D E F
UU, UU, UU, UU, UU, UU, UU, UU, BB, TT, NN, UU, FF, RR, UU, UU, // 0
UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, // 1
__, __, QU, __, __, __, __, __, __, __, __, __, __, __, __, __, // 2
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 3
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 4
__, __, __, __, __, __, __, __, __, __, __, __, BS, __, __, __, // 5
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 6
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 7
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 8
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 9
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // A
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // B
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // C
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // D
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // E
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // F
];

// Pre-computed hex digit pairs for control characters
pub(crate) struct HexPair(u8, u8);

pub(crate) static HEX_BYTES: [HexPair; 32] = [
HexPair(b'0', b'0'),
HexPair(b'0', b'1'),
HexPair(b'0', b'2'),
HexPair(b'0', b'3'),
HexPair(b'0', b'4'),
HexPair(b'0', b'5'),
HexPair(b'0', b'6'),
HexPair(b'0', b'7'),
HexPair(b'0', b'8'),
HexPair(b'0', b'9'),
HexPair(b'0', b'a'),
HexPair(b'0', b'b'),
HexPair(b'0', b'c'),
HexPair(b'0', b'd'),
HexPair(b'0', b'e'),
HexPair(b'0', b'f'),
HexPair(b'1', b'0'),
HexPair(b'1', b'1'),
HexPair(b'1', b'2'),
HexPair(b'1', b'3'),
HexPair(b'1', b'4'),
HexPair(b'1', b'5'),
HexPair(b'1', b'6'),
HexPair(b'1', b'7'),
HexPair(b'1', b'8'),
HexPair(b'1', b'9'),
HexPair(b'1', b'a'),
HexPair(b'1', b'b'),
HexPair(b'1', b'c'),
HexPair(b'1', b'd'),
HexPair(b'1', b'e'),
HexPair(b'1', b'f'),
];
67 changes: 4 additions & 63 deletions src/lib.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -108,11 +108,13 @@
//! | `escape v_jsonescape` | 21.09 ms | 1.18× |
//! | `json-escape` | 22.43 ms | 1.25× |

#[cfg(target_arch = "aarch64")]
mod aarch64;
mod generic;
#[cfg(target_arch = "x86_64")]
mod x86;

#[cfg(target_arch = "aarch64")]
mod aarch64;
pub use generic::escape_generic;

const BB: u8 = b'b'; // \x08
const TT: u8 = b't'; // \x09
Expand Down Expand Up @@ -170,67 +172,6 @@ pub(crate) const HEX_BYTES: [(u8, u8); 256] = {
bytes
};

#[inline]
/// Cross platform generic implementation without any platform specific instructions
pub fn escape_generic<S: AsRef<str>>(input: S) -> String {
let s = input.as_ref();
let bytes = s.as_bytes();

// Estimate capacity - most strings don't need much escaping
// Add some padding for potential escapes
let estimated_capacity = bytes.len() + bytes.len() / 2 + 2;
let mut result = Vec::with_capacity(estimated_capacity);

result.push(b'"');

let mut start = 0;
let mut i = 0;

while i < bytes.len() {
let b = bytes[i];

// Use lookup table to check if escaping is needed
let escape_byte = ESCAPE[b as usize];

if escape_byte == 0 {
// No escape needed, continue scanning
i += 1;
continue;
}

// Copy any unescaped bytes before this position
if start < i {
result.extend_from_slice(&bytes[start..i]);
}

// Handle the escape
result.push(b'\\');
if escape_byte == UU {
// Unicode escape for control characters
result.extend_from_slice(b"u00");
let hex_digits = &HEX_BYTES[b as usize];
result.push(hex_digits.0);
result.push(hex_digits.1);
} else {
// Simple escape
result.push(escape_byte);
}

i += 1;
start = i;
}

// Copy any remaining unescaped bytes
if start < bytes.len() {
result.extend_from_slice(&bytes[start..]);
}

result.push(b'"');

// SAFETY: We only pushed valid UTF-8 bytes (original string bytes and ASCII escape sequences)
unsafe { String::from_utf8_unchecked(result) }
}

/// Main entry point for JSON string escaping with SIMD acceleration
/// If the platform is supported, the SIMD path will be used. Otherwise, the generic fallback will be used.
pub fn escape<S: AsRef<str>>(input: S) -> String {
Expand Down
Loading