Function highlight

src/Client/ClientBaseHelpers.cpp:158–513

}

void highlight(const String & query, std::vector<replxx::Replxx::Color> & colors, const Context & context, int cursor_position, bool rainbow_parentheses)
{
    using namespace replxx;

    /// The `colors` array maps to a Unicode code point position in a string into a color.
    /// A color is set for every position individually (not for a range).

    /// Empty input.
    if (colors.empty())
        return;

    /// The colors should be legible (and look gorgeous) in both dark and light themes.
    /// When modifying this, check it in both themes.

    static const std::unordered_map<Highlight, Replxx::Color> type_to_color =
    {
        {Highlight::keyword, replxx::color::bold(Replxx::Color::DEFAULT)},
        {Highlight::identifier, Replxx::Color::CYAN},
        {Highlight::function, Replxx::Color::BROWN},
        {Highlight::alias, replxx::color::rgb666(0, 4, 4)},
        {Highlight::substitution, Replxx::Color::MAGENTA},
        {Highlight::number, replxx::color::rgb666(0, 4, 0)},
        {Highlight::string, Replxx::Color::GREEN},
        {Highlight::string_escape, replxx::color::bold(Replxx::Color::LIGHTGRAY)},
        {Highlight::string_metacharacter, replxx::color::bold(Replxx::Color::BRIGHTMAGENTA)},
    };

    /// We set reasonably small limits for size/depth, because we don't want the CLI to be slow.
    /// While syntax highlighting is unneeded for long queries, which the user couldn't read anyway.

    const char * begin = query.data();
    const char * end = begin + query.size();
    Tokens tokens(begin, end, 10000, true);
    IParser::Pos token_iterator(
        tokens,
        static_cast<uint32_t>(context.getSettingsRef()[Setting::max_parser_depth]),
        static_cast<uint32_t>(context.getSettingsRef()[Setting::max_parser_backtracks])
    );
    Expected expected;
    expected.enable_highlighting = true;

    /// We don't do highlighting for foreign dialects, such as PRQL and Kusto.
    /// Only normal ClickHouse SQL queries are highlighted.

    ParserQuery parser(end, false, context.getSettingsRef()[Setting::implicit_select]);
    ASTPtr ast;
    bool parse_res = false;

    try
    {
        while (!token_iterator->isEnd())
        {
            parse_res = parser.parse(token_iterator, ast, expected);
            if (!parse_res)
                break;

            if (!token_iterator->isEnd() && token_iterator->type != TokenType::Semicolon)
            {