Is this cheating?

function rotLeft(a, d) {

 d = d % a.length;

 if(d){
       for(let i=0; i<d; i++) a.push(a.shift());
 }

 return a;

}

d => so that I avoid unnecessary shifts

Eg: 5 elements when rotated 12 times it's the same as rotating 2 times

Hence instead of rotating 12 times we only rotate 2 times

And if it has to be rotated 10 times it's the same as not rotating at all so return the original array