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use crate::functions::is_digit_lexer::is_digit;
use crate::functions::is_hex_digit::is_hex_digit;
use crate::functions::is_space::is_space;
use crate::functions::to_utf_8::to_utf_8;
use crate::functions::unescape::unescape;
use crate::records::lexer::Lexer;
use alloc::vec::Vec;
use luaur_common::LUAU_ASSERT;
impl Lexer {
#[allow(non_snake_case)]
pub fn fixup_quoted_bytes(data: &mut Vec<u8>) -> bool {
if data.is_empty() || !data.contains(&b'\\') {
return true;
}
let size = data.len();
let mut write = 0;
let mut i = 0;
while i < size {
if data[i] != b'\\' {
data[write] = data[i];
write += 1;
i += 1;
continue;
}
if i + 1 == size {
return false;
}
let escape = data[i + 1] as char;
i += 2; // skip \e
match escape {
'\n' => {
data[write] = b'\n';
write += 1;
}
'\r' => {
data[write] = b'\n';
write += 1;
if i < size && data[i] == b'\n' {
i += 1;
}
}
'\0' => {
return false;
}
'x' => {
// hex escape codes are exactly 2 hex digits long
if i + 2 > size {
return false;
}
let mut code: u32 = 0;
for j in 0..2 {
let ch = data[i + j] as char;
if !is_hex_digit(ch) {
return false;
}
// use or trick to convert to lower case
code = 16 * code
+ (if is_digit(ch) {
(ch as u32) - ('0' as u32)
} else {
((ch as u32) | 32) - ('a' as u32) + 10
});
}
data[write] = code as u8;
write += 1;
i += 2;
}
'z' => {
while i < size && is_space(data[i] as char) {
i += 1;
}
}
'u' => {
// unicode escape codes are at least 3 characters including braces
if i + 3 > size {
return false;
}
if data[i] != b'{' {
return false;
}
i += 1;
if i < size && data[i] == b'}' {
return false;
}
let mut code: u32 = 0;
let mut found_brace = false;
for _ in 0..16 {
if i == size {
return false;
}
let ch = data[i] as char;
if ch == '}' {
found_brace = true;
break;
}
if !is_hex_digit(ch) {
return false;
}
// use or trick to convert to lower case.
// C++ `code` is `unsigned int` and wraps on overflow.
code = code.wrapping_mul(16).wrapping_add(if is_digit(ch) {
(ch as u32) - ('0' as u32)
} else {
((ch as u32) | 32) - ('a' as u32) + 10
});
i += 1;
}
if !found_brace || i == size || data[i] != b'}' {
return false;
}
i += 1;
let utf8_len = to_utf_8(&mut data[write..], code);
if utf8_len == 0 {
return false;
}
write += utf8_len;
}
_ => {
if is_digit(escape) {
let mut code = (escape as u32) - ('0' as u32);
for _ in 0..2 {
if i == size || !is_digit(data[i] as char) {
break;
}
code = 10 * code + ((data[i] as u32) - ('0' as u32));
i += 1;
}
if code > 255 {
return false;
}
data[write] = code as u8;
write += 1;
} else {
data[write] = unescape(escape) as u8;
write += 1;
}
}
}
}
LUAU_ASSERT!(write <= size);
data.truncate(write);
true
}
}