Add a Converter type for token conversion

This commit is contained in:
Jonas Schievink 2022-05-02 17:47:12 +02:00
parent f83dccf5b9
commit 1f50e19eb2

View File

@ -29,29 +29,19 @@ struct LexError {
impl<'a> LexedStr<'a> {
pub fn new(text: &'a str) -> LexedStr<'a> {
let mut res = LexedStr { text, kind: Vec::new(), start: Vec::new(), error: Vec::new() };
let mut offset = 0;
let mut conv = Converter::new(text);
if let Some(shebang_len) = rustc_lexer::strip_shebang(text) {
res.push(SHEBANG, offset);
offset = shebang_len
conv.res.push(SHEBANG, conv.offset);
conv.offset = shebang_len;
};
for token in rustc_lexer::tokenize(&text[offset..]) {
let token_text = &text[offset..][..token.len];
let (kind, err) = from_rustc(&token.kind, token_text);
res.push(kind, offset);
offset += token.len;
for token in rustc_lexer::tokenize(&text[conv.offset..]) {
let token_text = &text[conv.offset..][..token.len];
if let Some(err) = err {
let token = res.len() as u32;
let msg = err.to_string();
res.error.push(LexError { msg, token });
}
conv.extend_token(&token.kind, token_text);
}
res.push(EOF, offset);
res
conv.finalize_with_eof()
}
pub fn single_token(text: &'a str) -> Option<(SyntaxKind, Option<String>)> {
@ -64,8 +54,12 @@ pub fn single_token(text: &'a str) -> Option<(SyntaxKind, Option<String>)> {
return None;
}
let (kind, err) = from_rustc(&token.kind, text);
Some((kind, err.map(|it| it.to_owned())))
let mut conv = Converter::new(text);
conv.extend_token(&token.kind, text);
match &*conv.res.kind {
[kind] => Some((*kind, conv.res.error.pop().map(|it| it.msg.clone()))),
_ => None,
}
}
pub fn as_str(&self) -> &str {
@ -128,148 +122,179 @@ fn push(&mut self, kind: SyntaxKind, offset: usize) {
}
}
/// Returns `SyntaxKind` and an optional tokenize error message.
fn from_rustc(
kind: &rustc_lexer::TokenKind,
token_text: &str,
) -> (SyntaxKind, Option<&'static str>) {
// A note on an intended tradeoff:
// We drop some useful information here (see patterns with double dots `..`)
// Storing that info in `SyntaxKind` is not possible due to its layout requirements of
// being `u16` that come from `rowan::SyntaxKind`.
let mut err = "";
struct Converter<'a> {
res: LexedStr<'a>,
offset: usize,
}
let syntax_kind = {
match kind {
rustc_lexer::TokenKind::LineComment { doc_style: _ } => COMMENT,
rustc_lexer::TokenKind::BlockComment { doc_style: _, terminated } => {
impl<'a> Converter<'a> {
fn new(text: &'a str) -> Self {
Self {
res: LexedStr { text, kind: Vec::new(), start: Vec::new(), error: Vec::new() },
offset: 0,
}
}
fn finalize_with_eof(mut self) -> LexedStr<'a> {
self.res.push(EOF, self.offset);
self.res
}
fn push(&mut self, kind: SyntaxKind, len: usize, err: Option<&str>) {
self.res.push(kind, self.offset);
self.offset += len;
if let Some(err) = err {
let token = self.res.len() as u32;
let msg = err.to_string();
self.res.error.push(LexError { msg, token });
}
}
fn extend_token(&mut self, kind: &rustc_lexer::TokenKind, token_text: &str) {
// A note on an intended tradeoff:
// We drop some useful information here (see patterns with double dots `..`)
// Storing that info in `SyntaxKind` is not possible due to its layout requirements of
// being `u16` that come from `rowan::SyntaxKind`.
let mut err = "";
let syntax_kind = {
match kind {
rustc_lexer::TokenKind::LineComment { doc_style: _ } => COMMENT,
rustc_lexer::TokenKind::BlockComment { doc_style: _, terminated } => {
if !terminated {
err = "Missing trailing `*/` symbols to terminate the block comment";
}
COMMENT
}
rustc_lexer::TokenKind::Whitespace => WHITESPACE,
rustc_lexer::TokenKind::Ident if token_text == "_" => UNDERSCORE,
rustc_lexer::TokenKind::Ident => {
SyntaxKind::from_keyword(token_text).unwrap_or(IDENT)
}
rustc_lexer::TokenKind::RawIdent => IDENT,
rustc_lexer::TokenKind::Literal { kind, .. } => {
self.extend_literal(token_text.len(), kind);
return;
}
rustc_lexer::TokenKind::Lifetime { starts_with_number } => {
if *starts_with_number {
err = "Lifetime name cannot start with a number";
}
LIFETIME_IDENT
}
rustc_lexer::TokenKind::Semi => T![;],
rustc_lexer::TokenKind::Comma => T![,],
rustc_lexer::TokenKind::Dot => T![.],
rustc_lexer::TokenKind::OpenParen => T!['('],
rustc_lexer::TokenKind::CloseParen => T![')'],
rustc_lexer::TokenKind::OpenBrace => T!['{'],
rustc_lexer::TokenKind::CloseBrace => T!['}'],
rustc_lexer::TokenKind::OpenBracket => T!['['],
rustc_lexer::TokenKind::CloseBracket => T![']'],
rustc_lexer::TokenKind::At => T![@],
rustc_lexer::TokenKind::Pound => T![#],
rustc_lexer::TokenKind::Tilde => T![~],
rustc_lexer::TokenKind::Question => T![?],
rustc_lexer::TokenKind::Colon => T![:],
rustc_lexer::TokenKind::Dollar => T![$],
rustc_lexer::TokenKind::Eq => T![=],
rustc_lexer::TokenKind::Bang => T![!],
rustc_lexer::TokenKind::Lt => T![<],
rustc_lexer::TokenKind::Gt => T![>],
rustc_lexer::TokenKind::Minus => T![-],
rustc_lexer::TokenKind::And => T![&],
rustc_lexer::TokenKind::Or => T![|],
rustc_lexer::TokenKind::Plus => T![+],
rustc_lexer::TokenKind::Star => T![*],
rustc_lexer::TokenKind::Slash => T![/],
rustc_lexer::TokenKind::Caret => T![^],
rustc_lexer::TokenKind::Percent => T![%],
rustc_lexer::TokenKind::Unknown => ERROR,
}
};
let err = if err.is_empty() { None } else { Some(err) };
self.push(syntax_kind, token_text.len(), err);
}
fn extend_literal(&mut self, len: usize, kind: &rustc_lexer::LiteralKind) {
let mut err = "";
let syntax_kind = match *kind {
rustc_lexer::LiteralKind::Int { empty_int, base: _ } => {
if empty_int {
err = "Missing digits after the integer base prefix";
}
INT_NUMBER
}
rustc_lexer::LiteralKind::Float { empty_exponent, base: _ } => {
if empty_exponent {
err = "Missing digits after the exponent symbol";
}
FLOAT_NUMBER
}
rustc_lexer::LiteralKind::Char { terminated } => {
if !terminated {
err = "Missing trailing `*/` symbols to terminate the block comment";
err = "Missing trailing `'` symbol to terminate the character literal";
}
COMMENT
CHAR
}
rustc_lexer::TokenKind::Whitespace => WHITESPACE,
rustc_lexer::TokenKind::Ident if token_text == "_" => UNDERSCORE,
rustc_lexer::TokenKind::Ident => SyntaxKind::from_keyword(token_text).unwrap_or(IDENT),
rustc_lexer::TokenKind::RawIdent => IDENT,
rustc_lexer::TokenKind::Literal { kind, .. } => return from_rustc_literal(kind),
rustc_lexer::TokenKind::Lifetime { starts_with_number } => {
if *starts_with_number {
err = "Lifetime name cannot start with a number";
rustc_lexer::LiteralKind::Byte { terminated } => {
if !terminated {
err = "Missing trailing `'` symbol to terminate the byte literal";
}
LIFETIME_IDENT
BYTE
}
rustc_lexer::TokenKind::Semi => T![;],
rustc_lexer::TokenKind::Comma => T![,],
rustc_lexer::TokenKind::Dot => T![.],
rustc_lexer::TokenKind::OpenParen => T!['('],
rustc_lexer::TokenKind::CloseParen => T![')'],
rustc_lexer::TokenKind::OpenBrace => T!['{'],
rustc_lexer::TokenKind::CloseBrace => T!['}'],
rustc_lexer::TokenKind::OpenBracket => T!['['],
rustc_lexer::TokenKind::CloseBracket => T![']'],
rustc_lexer::TokenKind::At => T![@],
rustc_lexer::TokenKind::Pound => T![#],
rustc_lexer::TokenKind::Tilde => T![~],
rustc_lexer::TokenKind::Question => T![?],
rustc_lexer::TokenKind::Colon => T![:],
rustc_lexer::TokenKind::Dollar => T![$],
rustc_lexer::TokenKind::Eq => T![=],
rustc_lexer::TokenKind::Bang => T![!],
rustc_lexer::TokenKind::Lt => T![<],
rustc_lexer::TokenKind::Gt => T![>],
rustc_lexer::TokenKind::Minus => T![-],
rustc_lexer::TokenKind::And => T![&],
rustc_lexer::TokenKind::Or => T![|],
rustc_lexer::TokenKind::Plus => T![+],
rustc_lexer::TokenKind::Star => T![*],
rustc_lexer::TokenKind::Slash => T![/],
rustc_lexer::TokenKind::Caret => T![^],
rustc_lexer::TokenKind::Percent => T![%],
rustc_lexer::TokenKind::Unknown => ERROR,
}
};
let err = if err.is_empty() { None } else { Some(err) };
(syntax_kind, err)
}
fn from_rustc_literal(kind: &rustc_lexer::LiteralKind) -> (SyntaxKind, Option<&'static str>) {
let mut err = "";
let syntax_kind = match *kind {
rustc_lexer::LiteralKind::Int { empty_int, base: _ } => {
if empty_int {
err = "Missing digits after the integer base prefix";
rustc_lexer::LiteralKind::Str { terminated } => {
if !terminated {
err = "Missing trailing `\"` symbol to terminate the string literal";
}
STRING
}
INT_NUMBER
}
rustc_lexer::LiteralKind::Float { empty_exponent, base: _ } => {
if empty_exponent {
err = "Missing digits after the exponent symbol";
rustc_lexer::LiteralKind::ByteStr { terminated } => {
if !terminated {
err = "Missing trailing `\"` symbol to terminate the byte string literal";
}
BYTE_STRING
}
FLOAT_NUMBER
}
rustc_lexer::LiteralKind::Char { terminated } => {
if !terminated {
err = "Missing trailing `'` symbol to terminate the character literal";
}
CHAR
}
rustc_lexer::LiteralKind::Byte { terminated } => {
if !terminated {
err = "Missing trailing `'` symbol to terminate the byte literal";
}
BYTE
}
rustc_lexer::LiteralKind::Str { terminated } => {
if !terminated {
err = "Missing trailing `\"` symbol to terminate the string literal";
}
STRING
}
rustc_lexer::LiteralKind::ByteStr { terminated } => {
if !terminated {
err = "Missing trailing `\"` symbol to terminate the byte string literal";
}
BYTE_STRING
}
rustc_lexer::LiteralKind::RawStr { err: raw_str_err, .. } => {
if let Some(raw_str_err) = raw_str_err {
err = match raw_str_err {
rustc_lexer::RawStrError::InvalidStarter { .. } => "Missing `\"` symbol after `#` symbols to begin the raw string literal",
rustc_lexer::RawStrError::NoTerminator { expected, found, .. } => if expected == found {
"Missing trailing `\"` to terminate the raw string literal"
} else {
"Missing trailing `\"` with `#` symbols to terminate the raw string literal"
},
rustc_lexer::RawStrError::TooManyDelimiters { .. } => "Too many `#` symbols: raw strings may be delimited by up to 65535 `#` symbols",
rustc_lexer::LiteralKind::RawStr { err: raw_str_err, .. } => {
if let Some(raw_str_err) = raw_str_err {
err = match raw_str_err {
rustc_lexer::RawStrError::InvalidStarter { .. } => "Missing `\"` symbol after `#` symbols to begin the raw string literal",
rustc_lexer::RawStrError::NoTerminator { expected, found, .. } => if expected == found {
"Missing trailing `\"` to terminate the raw string literal"
} else {
"Missing trailing `\"` with `#` symbols to terminate the raw string literal"
},
rustc_lexer::RawStrError::TooManyDelimiters { .. } => "Too many `#` symbols: raw strings may be delimited by up to 65535 `#` symbols",
};
};
};
STRING
}
rustc_lexer::LiteralKind::RawByteStr { err: raw_str_err, .. } => {
if let Some(raw_str_err) = raw_str_err {
err = match raw_str_err {
rustc_lexer::RawStrError::InvalidStarter { .. } => "Missing `\"` symbol after `#` symbols to begin the raw byte string literal",
rustc_lexer::RawStrError::NoTerminator { expected, found, .. } => if expected == found {
"Missing trailing `\"` to terminate the raw byte string literal"
} else {
"Missing trailing `\"` with `#` symbols to terminate the raw byte string literal"
},
rustc_lexer::RawStrError::TooManyDelimiters { .. } => "Too many `#` symbols: raw byte strings may be delimited by up to 65535 `#` symbols",
STRING
}
rustc_lexer::LiteralKind::RawByteStr { err: raw_str_err, .. } => {
if let Some(raw_str_err) = raw_str_err {
err = match raw_str_err {
rustc_lexer::RawStrError::InvalidStarter { .. } => "Missing `\"` symbol after `#` symbols to begin the raw byte string literal",
rustc_lexer::RawStrError::NoTerminator { expected, found, .. } => if expected == found {
"Missing trailing `\"` to terminate the raw byte string literal"
} else {
"Missing trailing `\"` with `#` symbols to terminate the raw byte string literal"
},
rustc_lexer::RawStrError::TooManyDelimiters { .. } => "Too many `#` symbols: raw byte strings may be delimited by up to 65535 `#` symbols",
};
};
};
BYTE_STRING
}
};
BYTE_STRING
}
};
let err = if err.is_empty() { None } else { Some(err) };
(syntax_kind, err)
let err = if err.is_empty() { None } else { Some(err) };
self.push(syntax_kind, len, err);
}
}