Fix FormattedValue location

This commit is contained in:
harupy 2022-12-30 21:39:29 +09:00
parent 4e00ba2c50
commit faec9372f9
22 changed files with 2195 additions and 355 deletions

562
parser/src/string_parser.rs Normal file
View file

@ -0,0 +1,562 @@
use self::FStringErrorType::*;
use crate::{
ast::{Constant, ConversionFlag, Expr, ExprKind, Location},
error::{FStringErrorType, LexicalError, LexicalErrorType, ParseError},
parser::parse_expression_located,
token::StringKind,
};
use std::{iter, mem, str};
/// unicode_name2 does not expose `MAX_NAME_LENGTH`, so we replicate that constant here, fix #3798
pub const MAX_UNICODE_NAME: usize = 88;
pub struct StringParser<'a> {
chars: iter::Peekable<str::Chars<'a>>,
kind: StringKind,
str_start: Location,
str_end: Location,
location: Location,
}
impl<'a> StringParser<'a> {
pub fn new(
source: &'a str,
kind: StringKind,
triple_quoted: bool,
str_start: Location,
str_end: Location,
) -> Self {
let offset = kind.to_string().len() + if triple_quoted { 3 } else { 1 };
Self {
chars: source.chars().peekable(),
kind,
str_start,
str_end,
location: Location::new(str_start.row(), str_start.column() + offset),
}
}
fn next_char(&mut self) -> Option<char> {
let Some(c) = self.chars.next() else {
return None
};
if c == '\n' {
self.location.newline();
} else {
self.location.go_right();
}
Some(c)
}
fn peek(&mut self) -> Option<&char> {
self.chars.peek()
}
fn get_pos(&self) -> Location {
self.location
}
#[inline]
fn expr(&self, node: ExprKind) -> Expr {
Expr::new(self.str_start, self.str_end, node)
}
fn parse_unicode_literal(&mut self, literal_number: usize) -> Result<char, LexicalError> {
let mut p: u32 = 0u32;
let unicode_error = LexicalError {
error: LexicalErrorType::UnicodeError,
location: self.get_pos(),
};
for i in 1..=literal_number {
match self.next_char() {
Some(c) => match c.to_digit(16) {
Some(d) => p += d << ((literal_number - i) * 4),
None => return Err(unicode_error),
},
None => return Err(unicode_error),
}
}
match p {
0xD800..=0xDFFF => Ok(std::char::REPLACEMENT_CHARACTER),
_ => std::char::from_u32(p).ok_or(unicode_error),
}
}
fn parse_octet(&mut self, first: char) -> char {
let mut octet_content = String::new();
octet_content.push(first);
while octet_content.len() < 3 {
if let Some('0'..='7') = self.peek() {
octet_content.push(self.next_char().unwrap())
} else {
break;
}
}
let value = u32::from_str_radix(&octet_content, 8).unwrap();
char::from_u32(value).unwrap()
}
fn parse_unicode_name(&mut self) -> Result<char, LexicalError> {
let start_pos = self.get_pos();
match self.next_char() {
Some('{') => {}
_ => {
return Err(LexicalError {
error: LexicalErrorType::StringError,
location: start_pos,
})
}
}
let start_pos = self.get_pos();
let mut name = String::new();
loop {
match self.next_char() {
Some('}') => break,
Some(c) => name.push(c),
None => {
return Err(LexicalError {
error: LexicalErrorType::StringError,
location: self.get_pos(),
})
}
}
}
if name.len() > MAX_UNICODE_NAME {
return Err(LexicalError {
error: LexicalErrorType::UnicodeError,
location: self.get_pos(),
});
}
unicode_names2::character(&name).ok_or(LexicalError {
error: LexicalErrorType::UnicodeError,
location: start_pos,
})
}
fn parse_escaped_char(&mut self) -> Result<String, LexicalError> {
match self.next_char() {
Some(c) => Ok(match c {
'\\' => '\\'.to_string(),
'\'' => '\''.to_string(),
'\"' => '"'.to_string(),
'\n' => "".to_string(),
'a' => '\x07'.to_string(),
'b' => '\x08'.to_string(),
'f' => '\x0c'.to_string(),
'n' => '\n'.to_string(),
'r' => '\r'.to_string(),
't' => '\t'.to_string(),
'v' => '\x0b'.to_string(),
o @ '0'..='7' => self.parse_octet(o).to_string(),
'x' => self.parse_unicode_literal(2)?.to_string(),
'u' if !self.kind.is_bytes() => self.parse_unicode_literal(4)?.to_string(),
'U' if !self.kind.is_bytes() => self.parse_unicode_literal(8)?.to_string(),
'N' if !self.kind.is_bytes() => self.parse_unicode_name()?.to_string(),
c => {
if self.kind.is_bytes() && !c.is_ascii() {
return Err(LexicalError {
error: LexicalErrorType::OtherError(
"bytes can only contain ASCII literal characters".to_owned(),
),
location: self.get_pos(),
});
}
format!("\\{c}")
}
}),
None => Err(LexicalError {
error: LexicalErrorType::StringError,
location: self.get_pos(),
}),
}
}
fn parse_formatted_value(&mut self, nested: u8) -> Result<Vec<Expr>, LexicalError> {
let mut expression = String::new();
let mut spec = None;
let mut delims = Vec::new();
let mut conversion = ConversionFlag::None;
let mut self_documenting = false;
let mut trailing_seq = String::new();
let location = self.get_pos();
while let Some(ch) = self.next_char() {
match ch {
// can be integrated better with the remaining code, but as a starting point ok
// in general I would do here a tokenizing of the fstrings to omit this peeking.
'!' if self.peek() == Some(&'=') => {
expression.push_str("!=");
self.next_char();
}
'=' if self.peek() == Some(&'=') => {
expression.push_str("==");
self.next_char();
}
'>' if self.peek() == Some(&'=') => {
expression.push_str(">=");
self.next_char();
}
'<' if self.peek() == Some(&'=') => {
expression.push_str("<=");
self.next_char();
}
'!' if delims.is_empty() && self.peek() != Some(&'=') => {
if expression.trim().is_empty() {
return Err(EmptyExpression.to_lexical_error(self.get_pos()));
}
conversion = match self.next_char() {
Some('s') => ConversionFlag::Str,
Some('a') => ConversionFlag::Ascii,
Some('r') => ConversionFlag::Repr,
Some(_) => {
return Err(if expression.trim().is_empty() {
EmptyExpression.to_lexical_error(self.get_pos())
} else {
InvalidConversionFlag.to_lexical_error(self.get_pos())
});
}
None => {
return Err(if expression.trim().is_empty() {
EmptyExpression.to_lexical_error(self.get_pos())
} else {
UnclosedLbrace.to_lexical_error(self.get_pos())
});
}
};
if let Some(&peek) = self.peek() {
if peek != '}' && peek != ':' {
return Err(if expression.trim().is_empty() {
EmptyExpression.to_lexical_error(self.get_pos())
} else {
UnclosedLbrace.to_lexical_error(self.get_pos())
});
}
} else {
return Err(if expression.trim().is_empty() {
EmptyExpression.to_lexical_error(self.get_pos())
} else {
UnclosedLbrace.to_lexical_error(self.get_pos())
});
}
}
// match a python 3.8 self documenting expression
// format '{' PYTHON_EXPRESSION '=' FORMAT_SPECIFIER? '}'
'=' if self.peek() != Some(&'=') && delims.is_empty() => {
self_documenting = true;
}
':' if delims.is_empty() => {
let parsed_spec = self.parse_spec(nested)?;
spec = Some(Box::new(self.expr(ExprKind::JoinedStr {
values: parsed_spec,
})));
}
'(' | '{' | '[' => {
expression.push(ch);
delims.push(ch);
}
')' => {
let last_delim = delims.pop();
match last_delim {
Some('(') => {
expression.push(ch);
}
Some(c) => {
return Err(
MismatchedDelimiter(c, ')').to_lexical_error(self.get_pos())
);
}
None => {
return Err(Unmatched(')').to_lexical_error(self.get_pos()));
}
}
}
']' => {
let last_delim = delims.pop();
match last_delim {
Some('[') => {
expression.push(ch);
}
Some(c) => {
return Err(
MismatchedDelimiter(c, ']').to_lexical_error(self.get_pos())
);
}
None => {
return Err(Unmatched(']').to_lexical_error(self.get_pos()));
}
}
}
'}' if !delims.is_empty() => {
let last_delim = delims.pop();
match last_delim {
Some('{') => {
expression.push(ch);
}
Some(c) => {
return Err(MismatchedDelimiter(c, '}').to_lexical_error(self.get_pos()))
}
None => {}
}
}
'}' => {
if expression.trim().is_empty() {
return Err(EmptyExpression.to_lexical_error(self.get_pos()));
}
let ret = if !self_documenting {
vec![self.expr(ExprKind::FormattedValue {
value: Box::new(parse_fstring_expr(&expression, location).map_err(
|e| {
InvalidExpression(Box::new(e.error))
.to_lexical_error(self.get_pos())
},
)?),
conversion: conversion as _,
format_spec: spec,
})]
} else {
vec![
self.expr(ExprKind::Constant {
value: Constant::Str(expression.to_owned() + "="),
kind: None,
}),
self.expr(ExprKind::Constant {
value: trailing_seq.into(),
kind: None,
}),
self.expr(ExprKind::FormattedValue {
value: Box::new(
parse_fstring_expr(&expression, location).map_err(|e| {
InvalidExpression(Box::new(e.error))
.to_lexical_error(self.get_pos())
})?,
),
conversion: (if conversion == ConversionFlag::None && spec.is_none()
{
ConversionFlag::Repr
} else {
conversion
}) as _,
format_spec: spec,
}),
]
};
return Ok(ret);
}
'"' | '\'' => {
expression.push(ch);
loop {
let Some(c) = self.next_char() else {
return Err(UnterminatedString.to_lexical_error(self.get_pos()));
};
expression.push(c);
if c == ch {
break;
}
}
}
' ' if self_documenting => {
trailing_seq.push(ch);
}
'\\' => return Err(ExpressionCannotInclude('\\').to_lexical_error(self.get_pos())),
_ => {
if self_documenting {
return Err(UnclosedLbrace.to_lexical_error(self.get_pos()));
}
expression.push(ch);
}
}
}
Err(if expression.trim().is_empty() {
EmptyExpression.to_lexical_error(self.get_pos())
} else {
UnclosedLbrace.to_lexical_error(self.get_pos())
})
}
fn parse_spec(&mut self, nested: u8) -> Result<Vec<Expr>, LexicalError> {
let mut spec_constructor = Vec::new();
let mut constant_piece = String::new();
while let Some(&next) = self.peek() {
match next {
'{' => {
if !constant_piece.is_empty() {
spec_constructor.push(self.expr(ExprKind::Constant {
value: constant_piece.to_owned().into(),
kind: None,
}));
constant_piece.clear();
}
let parsed_expr = self.parse_fstring(nested + 1)?;
spec_constructor.extend(parsed_expr);
continue;
}
'}' => {
break;
}
_ => {
constant_piece.push(next);
}
}
self.next_char();
}
if !constant_piece.is_empty() {
spec_constructor.push(self.expr(ExprKind::Constant {
value: constant_piece.to_owned().into(),
kind: None,
}));
constant_piece.clear();
}
Ok(spec_constructor)
}
fn parse_fstring(&mut self, nested: u8) -> Result<Vec<Expr>, LexicalError> {
if nested >= 2 {
return Err(ExpressionNestedTooDeeply.to_lexical_error(self.get_pos()));
}
let mut content = String::new();
let mut values = vec![];
while let Some(&ch) = self.peek() {
match ch {
'{' => {
self.next_char();
if nested == 0 {
match self.peek() {
Some('{') => {
self.next_char();
content.push('{');
continue;
}
None => return Err(UnclosedLbrace.to_lexical_error(self.get_pos())),
_ => {}
}
}
if !content.is_empty() {
values.push(self.expr(ExprKind::Constant {
value: mem::take(&mut content).into(),
kind: None,
}));
}
let parsed_values = self.parse_formatted_value(nested)?;
values.extend(parsed_values);
}
'}' => {
if nested > 0 {
break;
}
self.next_char();
if let Some('}') = self.peek() {
self.next_char();
content.push('}');
} else {
return Err(SingleRbrace.to_lexical_error(self.get_pos()));
}
}
'\\' if !self.kind.is_raw() => {
self.next_char();
content.push_str(&self.parse_escaped_char()?);
}
_ => {
content.push(ch);
self.next_char();
}
}
}
if !content.is_empty() {
values.push(self.expr(ExprKind::Constant {
value: content.into(),
kind: None,
}))
}
Ok(values)
}
pub fn parse_bytes(&mut self) -> Result<Expr, LexicalError> {
let mut content = String::new();
while let Some(ch) = self.next_char() {
match ch {
'\\' if !self.kind.is_raw() => {
content.push_str(&self.parse_escaped_char()?);
}
ch => {
if !ch.is_ascii() {
return Err(LexicalError {
error: LexicalErrorType::OtherError(
"bytes can only contain ASCII literal characters".to_string(),
),
location: self.get_pos(),
});
}
content.push(ch);
}
}
}
Ok(self.expr(ExprKind::Constant {
value: Constant::Bytes(content.chars().map(|c| c as u8).collect()),
kind: None,
}))
}
pub fn parse_string(&mut self) -> Result<Expr, LexicalError> {
let mut content = String::new();
while let Some(ch) = self.next_char() {
match ch {
'\\' if !self.kind.is_raw() => {
content.push_str(&self.parse_escaped_char()?);
}
ch => content.push(ch),
}
}
Ok(self.expr(ExprKind::Constant {
value: Constant::Str(content),
kind: self.kind.is_unicode().then(|| "u".to_string()),
}))
}
pub fn parse(&mut self) -> Result<Vec<Expr>, LexicalError> {
if self.kind.is_fstring() {
self.parse_fstring(0)
} else if self.kind.is_bytes() {
self.parse_bytes().map(|expr| vec![expr])
} else {
self.parse_string().map(|expr| vec![expr])
}
}
}
fn parse_fstring_expr(source: &str, location: Location) -> Result<Expr, ParseError> {
let fstring_body = format!("({source})");
parse_expression_located(
&fstring_body,
"<fstring>",
Location::new(location.row(), location.column() - 1),
)
}
pub fn parse_string(
source: &str,
kind: StringKind,
triple_quoted: bool,
start: Location,
end: Location,
) -> Result<Vec<Expr>, LexicalError> {
StringParser::new(source, kind, triple_quoted, start, end).parse()
}