find duplicate values in array object javascript

const values = [
  { name: 'someName1' },
  { name: 'someName2' },
  { name: 'someName3' },
  { name: 'someName1' }
]

const uniqueValues = new Set(values.map(v => v.name));

if (uniqueValues.size < values.length) {
  console.log('uniqueValues')
}

const values = [{id: 10, name: 'someName1'}, {id: 10, name: 'someName2'}, {id: 11, name:'someName3'}, {id: 12, name: 'someName4'}];

const lookup = values.reduce((a, e) => {
  a[e.id] = ++a[e.id] || 0;
  return a;
}, {});

console.log(values.filter(e => lookup[e.id]));
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function getUnique(arr, comp) {

                    // store the comparison  values in array
   const unique =  arr.map(e => e[comp])

                  // store the indexes of the unique objects
                  .map((e, i, final) => final.indexOf(e) === i && i)

                  // eliminate the false indexes & return unique objects
                 .filter((e) => arr[e]).map(e => arr[e]);

   return unique;
}

console.log(getUnique(arr,'id'));

duplicateIds = arr
     .map(e => e['id'])
     .map((e, i, final) => final.indexOf(e) !== i && i)
     .filter(obj=> arr[obj])
     .map(e => arr[e]["id"])