How to call array.push() if item does not exist with JavaScript?

To call array.push() if item does not exist with JavaScript, we use findIndex to check for item before we call push.

For instance, we write

const arrayObj = [
  { name: "bull", text: "red" },
  { name: "tom", text: "tasty" },
  { name: "tom", text: "tasty" },
];
const index = arrayObj.findIndex((x) => x.name == "bob");
if (index === -1) {
  arrayObj.push(obj);
} else {
  console.log("object already exists");
}

to call findIndex to get the index of the first object with name equal to 'Bob'.

If it returns -1, then we call push to append obj as the last item of the arrayObj array.