js-shallow-comparison.js

function areEqualShallow(a, b) {
  for (const key in a) {
    if (!(key in b) || a[key] !== b[key]) {
      return false;
    }
  }
  for (const key in b) {
    if (!(key in a) || a[key] !== b[key]) {
      return false;
    }
  }
  return true;
}

const myFirstObject = {};
const mySecondObject = {};

console.log(areEqualShallow(myFirstObject, mySecondObject)); // > true

myFirstObject.hi = "mom";
mySecondObject.hi = "mom";

console.log(areEqualShallow(myFirstObject, mySecondObject)); // > true

myFirstObject.nested = {
  hi: "medium",
};
mySecondObject.nested = {
  hi: "medium",
};

console.log(areEqualShallow(myFirstObject, mySecondObject)); // > false