Method parse_escaped_char

crates/ruff_python_parser/src/string.rs:240–278

Parse an escaped character, returning the new character.

(&mut self)

    /// Parse an escaped character, returning the new character.
    fn parse_escaped_char(&mut self) -> Result<Option<EscapedChar>, LexicalError> {
        let Some(first_char) = self.next_char() else {
            // TODO: check when this error case happens
            return Err(LexicalError::new(
                LexicalErrorType::StringError,
                TextRange::empty(self.position()),
            ));
        };

        let new_char = match first_char {
            '\\' => '\\',
            '\'' => '\'',
            '\"' => '"',
            'a' => '\x07',
            'b' => '\x08',
            'f' => '\x0c',
            'n' => '\n',
            'r' => '\r',
            't' => '\t',
            'v' => '\x0b',
            o @ '0'..='7' => self.parse_octet(o as u8),
            'x' => self.parse_unicode_literal(2)?,
            'u' if !self.flags.is_byte_string() => self.parse_unicode_literal(4)?,
            'U' if !self.flags.is_byte_string() => self.parse_unicode_literal(8)?,
            'N' if !self.flags.is_byte_string() => self.parse_unicode_name()?,
            // Special cases where the escape sequence is not a single character
            '\n' => return Ok(None),
            '\r' => {
                if self.peek_byte() == Some(b'\n') {
                    self.next_byte();
                }

                return Ok(None);
            }
            _ => return Ok(Some(EscapedChar::Escape(first_char))),
        };

        Ok(Some(EscapedChar::Literal(new_char)))
    }

    fn parse_interpolated_string_middle(
        mut self,