Skip to content

fix(es/parser): Fix parsing of unicode characters #10723

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

Closed
wants to merge 1 commit into from
+44 −94
Closed

fix(es/parser): Fix parsing of unicode characters #10723

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
128 changes: 41 additions & 87 deletions crates/swc_ecma_lexer/src/common/lexer/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1134,26 +1134,31 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
op(self, &mut buf)
}

fn read_unicode_escape(&mut self) -> LexResult<Vec<Char>> {
fn read_unicode_escape(&mut self) -> LexResult<Char> {
debug_assert_eq!(self.cur(), Some('u'));

let mut chars = Vec::with_capacity(4);
let mut is_curly = false;

self.bump(); // 'u'

if self.eat(b'{') {
is_curly = true;
}
let is_curly = self.eat(b'{');

let state = self.input().cur_pos();
let c = match self.read_int_u32::<16>(if is_curly { 0 } else { 4 }) {
Ok(Some(val)) => {
if 0x0010_ffff >= val {
char::from_u32(val)
if val <= 0x0010_ffff {
char::from_u32(val).ok_or_else(|| {
let start = self.cur_pos();
crate::error::Error::new(
pos_span(start),
SyntaxError::BadCharacterEscapeSequence {
expected: if is_curly {
"1-6 hex characters in the range 0 to 10FFFF."
} else {
"4 hex characters"
},
},
)
})?
} else {
let start = self.cur_pos();

self.error(
start,
SyntaxError::BadCharacterEscapeSequence {
Expand All @@ -1168,7 +1173,6 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
}
_ => {
let start = self.cur_pos();

self.error(
start,
SyntaxError::BadCharacterEscapeSequence {
Expand All @@ -1182,54 +1186,12 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
}
};

match c {
Some(c) => {
chars.push(c.into());
}
_ => {
unsafe {
// Safety: state is valid position because we got it from cur_pos()
self.input_mut().reset_to(state);
}

chars.push(Char::from('\\'));
chars.push(Char::from('u'));

if is_curly {
chars.push(Char::from('{'));

for _ in 0..6 {
if let Some(c) = self.input().cur() {
if c == '}' {
break;
}

self.bump();

chars.push(Char::from(c));
} else {
break;
}
}

chars.push(Char::from('}'));
} else {
for _ in 0..4 {
if let Some(c) = self.input().cur() {
self.bump();

chars.push(Char::from(c));
}
}
}
}
}

if is_curly && !self.eat(b'}') {
self.error(state, SyntaxError::InvalidUnicodeEscape)?
let start = self.cur_pos();
self.error(start, SyntaxError::InvalidUnicodeEscape)?
}

Ok(chars)
Ok(c.into())
}

#[cold]
Expand Down Expand Up @@ -1359,9 +1321,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
match self.read_escaped_char(true) {
Ok(Some(chars)) => {
if let Ok(ref mut cooked) = cooked {
for c in chars {
cooked.extend(c);
}
cooked.extend(chars);
}
}
Ok(None) => {}
Expand All @@ -1380,7 +1340,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
/// Read an escaped character for string literal.
///
/// In template literal, we should preserve raw string.
fn read_escaped_char(&mut self, in_template: bool) -> LexResult<Option<Vec<Char>>> {
fn read_escaped_char(&mut self, in_template: bool) -> LexResult<Option<Char>> {
debug_assert_eq!(self.cur(), Some('\\'));

let start = self.cur_pos();
Expand Down Expand Up @@ -1418,7 +1378,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
self.bump(); // 'x'

match self.read_int_u32::<16>(2)? {
Some(val) => return Ok(Some(vec![Char::from(val)])),
Some(val) => return Ok(Some(Char::from(val))),
None => self.error(
start,
SyntaxError::BadCharacterEscapeSequence {
Expand All @@ -1429,10 +1389,10 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
}

// read unicode escape sequences
'u' => match self.read_unicode_escape() {
Ok(chars) => return Ok(Some(chars)),
Err(err) => self.error(start, err.into_kind())?,
},
'u' => {
let c = self.read_unicode_escape()?;
return Ok(Some(c));
}

// octal escape sequences
'0'..='7' => {
Expand All @@ -1442,7 +1402,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
match self.cur() {
Some(next) if next.is_digit(8) => c,
// \0 is not an octal literal nor decimal literal.
_ => return Ok(Some(vec!['\u{0000}'.into()])),
_ => return Ok(Some('\u{0000}'.into())),
}
} else {
c
Expand All @@ -1469,23 +1429,23 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
.and_then(|value| value.checked_add(v as u8));
match new_val {
Some(val) => val,
None => return Ok(Some(vec![Char::from(value as char)])),
None => return Ok(Some(Char::from(value as char))),
}
} else {
value * 8 + v as u8
};

self.bump();
}
_ => return Ok(Some(vec![Char::from(value as u32)])),
_ => return Ok(Some(Char::from(value as u32))),
}
}};
}

one!(false);
one!(true);

return Ok(Some(vec![Char::from(value as char)]));
return Ok(Some(Char::from(value as char)));
}
_ => c,
};
Expand All @@ -1495,7 +1455,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
self.input_mut().bump();
}

Ok(Some(vec![c.into()]))
Ok(Some(c.into()))
}

/// Expects current char to be '/'
Expand Down Expand Up @@ -1710,23 +1670,19 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
}
}

let chars = l.read_unicode_escape()?;
let c = l.read_unicode_escape()?;

if let Some(c) = chars.first() {
let valid = if first {
c.is_ident_start()
} else {
c.is_ident_part()
};
let valid = if first {
c.is_ident_start()
} else {
c.is_ident_part()
};

if !valid {
l.emit_error(start, SyntaxError::InvalidIdentChar);
}
if !valid {
l.emit_error(start, SyntaxError::InvalidIdentChar);
}

for c in chars {
buf.extend(c);
}
buf.extend(c);

slice_start = l.cur_pos();
continue;
Expand Down Expand Up @@ -2085,9 +2041,7 @@ pub trait Lexer<'a, TokenAndSpan>: Tokens<TokenAndSpan> + Sized {
}

if let Some(chars) = l.read_escaped_char(false)? {
for c in chars {
buf.extend(c);
}
buf.extend(chars);
}

slice_start = l.cur_pos();
Expand Down
4 changes: 1 addition & 3 deletions crates/swc_ecma_parser/src/lexer/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -405,9 +405,7 @@ impl Lexer<'_> {
match self.read_escaped_char(true) {
Ok(Some(chars)) => {
if let Ok(ref mut cooked) = cooked {
for c in chars {
cooked.extend(c);
}
cooked.extend(chars);
}
}
Ok(None) => {}
Expand Down
6 changes: 2 additions & 4 deletions crates/swc_ecma_parser/src/lexer/state.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -521,13 +521,11 @@ impl Lexer<'_> {
continue;
}
self.bump(); // bump 'u'
let Ok(chars) = self.read_unicode_escape() else {
let Ok(c) = self.read_unicode_escape() else {
self.emit_error(self.cur_pos(), SyntaxError::InvalidUnicodeEscape);
break;
};
for c in chars {
v.extend(c);
}
v.extend(c);
self.token_flags |= swc_ecma_lexer::lexer::TokenFlags::UNICODE;
} else {
break;
Expand Down
Loading