JSFiddle - React, Tailwind, and code Playground

JavaScript

var entry_54 = 'ABC111, ABC111, ABC112, ABC113';
//var entry_54 = '';


function testRepeatingPattern(str, pattern, separator, tolerateEmptyString, matchFn, failFn) {
    var dummy = tolerateEmptyString ? '' : '$d^u^m^m^y^S^t^r^i^n^g%';//good and strong
    var fn = (((str.match(pattern) || [dummy]).join(separator)) === str) ? (matchFn || function(){return true;}) : (failFn || function(){return false;});
    return fn();
}

alert(testRepeatingPattern(entry_54, /[A-Z]{3}[0-9]{3}/g, ', '));