const array1 = [
    {id: 1, name: "Foo Smith", isProv: true},
    {id: 2, name: "CAA", isProv: true}
];

const array2 = [
    {id: 2, name: "CAA"},
    {id: 3, name: "Bar Jones"}
];

// create map of the first array
const mapArr1 = {};
array1.forEach(v => {
  mapArr1[v.id] = v;
})

// iterate over second array
array2.forEach(v => {
  if(mapArr1[v.id]) { // check if object with the same id exist in first array

    // here you can do any kind of checks to both objects

    // in this case, we just merge both objects
    mapArr1[v.id] = Object.assign({}, mapArr1[v.id], v);


  } else { // if not, save the new value
    mapArr1[v.id] = v;
  }

});

const result = Object.keys(mapArr1).map(k => mapArr1[k]);