Deep Objects Compare

deep-objects-compare.js

function deepObjectsCompare(o1, o2) {
  if (!o1 || !o2) {
    if ((o1 === null && o2 !== null) || (o1 !== null && o2 === null)) {
      return false; // return false if one arg is null while another is undefined
    }
    return true; // return true if both args are null or undefined
  }
  //console.log(o1, o2);
  let keys1 = 0;
  for (let key in o1) { keys1++; }
  //console.log('keys1:', keys1);
  let keys2 = 0;
  for (let key in o2) { keys2++; }
  //console.log('keys2:', keys2);
  if (keys1 > 0 && keys2 > 0) {
    if (keys1 !== keys2) {
      return false; // return false if o1 and o2 keys count does not match
    }
    for (let key in o1) {
      if (o1[key] && o2[key]) {
        let nestedKeys1 = 0;
        for (let nestedKey in o1[key]) { nestedKeys1++; }
        //console.log('nested keys1:', nestedKeys1);
        let nestedKeys2 = 0;
        for (let nestedKey in o2[key]) { nestedKeys2++; }
        //console.log('nested keys2:', nestedKeys2);
        if (nestedKeys1 > 0 & nestedKeys2 > 0 && !o1.substring) {
          //console.log('nested object compare');
          const nestedCompareRes = deepObjectsCompare(o1[key], o2[key]);
          //console.log('nestedCompareRes:', nestedCompareRes);
          if (!nestedCompareRes) { return false; }
        } else if (o1[key] !== o2[key]) {
          //console.log('simple values, one is number:', o1[key], '|', o2[key]);
          return false; // return false if o1[key] and o2[key] are simple values and not equal each other
        }
      }
    }
  } else if (o1 !== o2) {
    //console.log('simple values, one is number:', o1, '|', o2);
    return false; // return false if o1 and o2 are simple values and not equal each other
  }
  return true;
};

// TEST
deepObjectsCompare(null, null); // true
deepObjectsCompare(null, undefined); // false
deepObjectsCompare(undefined, undefined); // true
deepObjectsCompare(1, 2); // false
deepObjectsCompare(1, 1); // true
deepObjectsCompare([1, 2], [1, 2]); // true
deepObjectsCompare([1, 2], [1, 1]); // false
deepObjectsCompare({ one: 'two' }, {one: 'two' }); // true
deepObjectsCompare({ one: 'two' }, {one: 'three' }); // false
deepObjectsCompare([1, { one: 'two' }], [1, {one: 'two' }]); // true
deepObjectsCompare([1, { one: 'two' }], [{one: 'three' }, 1]); // false

DeepObjectsCompare.markdown

Deep Objects Compare

Function deepObjectsCompare compares two objects provided as the function arguments.

Arguments can be of the following types: null, undefined, string, number, object, array.

Arguments may have nested objects. Arguments examples:

• deepObjectsCompare(1, 1)
• deepObjectsCompare([1, 2], [1, 2]);
• deepObjectsCompare({ one: 'two' }, {one: 'two' });
• deepObjectsCompare([1, { one: 'two' }], [1, {one: 'two' }]);

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License.