Searches for a value in a object

treesearch.js

function searchFor(val, s, all = true) {
    const results = [];

    const handleValue = (key, value, p) => {
        const da = typeof key === 'string' && key.match(/^[_a-zA-Z][\w\d_]*$/);
        const query = p + (da ? `.${key}` : `[${key}]`);

        if (value === s) {
            return query;
        } else if (typeof value === 'object') {
            search(value, query);
        }
    };

    function search(val, p = '') {
        if (typeof val === 'object') {
            for (const [key, value] of Object.entries(val)) {
                const res = handleValue(key, value, p);
                if (res) {
                    results.push(res.substr(1));
                    if (all) {
                        return;
                    }
                }
            }
        } else if (s === val) {
            return p + s;
        }
        return null;
    }

    search(val);
    if (all) {
        return results;
    } else {
        return results[0] || null;
    }
}