lib/generate.js
function createSizeSuffix(width, height) {
  let result = String(width);
  if (height !== undefined) result += `x${String(height)}`;
  return result;
}
function createSizeSuffix(width, height) {
  let result = String(width);
  if (height !== undefined) result += `x${String(height)}`;
  return result;
}
function createSizeSuffix ( width , height ) { let result = String ( width ) ; if ( height !== undefined ) result += ` ${ String ( height ) } ` ; return result ; }
Put width and height together into a dimension-representing suffix.

@param {number} [width]
@param {number} [height]
@return {string}
Put width and height together into a dimension - representing suffix .