fn tokenize_dollar_preceded_value()

in src/tokenizer.rs [1744:1834]

• 76 lines of code
• 20 McCabe index (conditional complexity)

    fn tokenize_dollar_preceded_value(&self, chars: &mut State) -> Result<Token, TokenizerError> {
        let mut s = String::new();
        let mut value = String::new();

        chars.next();

        // If the dialect does not support dollar-quoted strings, then `$$` is rather a placeholder.
        if matches!(chars.peek(), Some('$')) && !self.dialect.supports_dollar_placeholder() {
            chars.next();

            let mut is_terminated = false;
            let mut prev: Option<char> = None;

            while let Some(&ch) = chars.peek() {
                if prev == Some('$') {
                    if ch == '$' {
                        chars.next();
                        is_terminated = true;
                        break;
                    } else {
                        s.push('$');
                        s.push(ch);
                    }
                } else if ch != '$' {
                    s.push(ch);
                }

                prev = Some(ch);
                chars.next();
            }

            return if chars.peek().is_none() && !is_terminated {
                self.tokenizer_error(chars.location(), "Unterminated dollar-quoted string")
            } else {
                Ok(Token::DollarQuotedString(DollarQuotedString {
                    value: s,
                    tag: None,
                }))
            };
        } else {
            value.push_str(&peeking_take_while(chars, |ch| {
                ch.is_alphanumeric()
                    || ch == '_'
                    // Allow $ as a placeholder character if the dialect supports it
                    || matches!(ch, '$' if self.dialect.supports_dollar_placeholder())
            }));

            // If the dialect does not support dollar-quoted strings, don't look for the end delimiter.
            if matches!(chars.peek(), Some('$')) && !self.dialect.supports_dollar_placeholder() {
                chars.next();

                let mut temp = String::new();
                let end_delimiter = format!("${}$", value);

                loop {
                    match chars.next() {
                        Some(ch) => {
                            temp.push(ch);

                            if temp.ends_with(&end_delimiter) {
                                if let Some(temp) = temp.strip_suffix(&end_delimiter) {
                                    s.push_str(temp);
                                }
                                break;
                            }
                        }
                        None => {
                            if temp.ends_with(&end_delimiter) {
                                if let Some(temp) = temp.strip_suffix(&end_delimiter) {
                                    s.push_str(temp);
                                }
                                break;
                            }

                            return self.tokenizer_error(
                                chars.location(),
                                "Unterminated dollar-quoted, expected $",
                            );
                        }
                    }
                }
            } else {
                return Ok(Token::Placeholder(String::from("$") + &value));
            }
        }

        Ok(Token::DollarQuotedString(DollarQuotedString {
            value: s,
            tag: if value.is_empty() { None } else { Some(value) },
        }))
    }