Compare two version numbers that follows the semantic version standard

semanticVersionComparator.js

/**
 * Created by david on 17/1/16.
 */

/**
 * Compares two version numbers that follow the semantic version standard.
 * Compares only the first 3 elements (major, minor and patch).
 * Separator can be '.' or '-'.
 * If a>b, returns 1
 * If a<b, returns -1
 * If a=b, returns 0
 * @param a
 * @param b
 * @returns {number}
 */
module.exports = function compare(a, b) {
    var pa = a.split(/[\.\-]/); // split by either '.' or '-'
    var pb = b.split(/[\.\-]/);
    for (var i = 0; i < 3; i++) {
        var na = Number(pa[i]);
        var nb = Number(pb[i]);
        if (na > nb) return 1;
        if (nb > na) return -1;
        if (!isNaN(na) && isNaN(nb)) return 1;
        if (isNaN(na) && !isNaN(nb)) return -1;
    }
    return 0;
};