Quick thingy I made to copy while renaming certain props from an object to another

propertyMapper.mjs

// PLEASE NOTE: this is LAZY! It will only yield properties that are part of `namesMap`
// not all properties of `source`
export function *transformPropertyNames (source, namesMap) {
  for (
    const [ entryKey, targetKey ] of typeof namesMap[Symbol.iterator] === "function"
      ? namesMap // iterable
      : Object.entries(namesMap) // object-style
  )
    yield [ targetKey, source[entryKey] ];
}

export const xToXModel = (idFn => function xToXModel (propMap, propMapper = idFn) {
  if (propMapper === idFn)
    return x => Object.fromEntries(transformPropertyNames(x, propMap));

  return function (x) {
    const target = {};

    for (const [ k, v ] of transformPropertyNames(x, propMap))
      target[k] = propMapper(v, k);

    return target;
  };
})(x => x);

// Use
const userToUserModel = xToXModel({
  CUSTOMERNUMBER: "CustomerNumber",
  CITY: "City",
});

dbUsers.map(userToUserModel);