How to get all duplicated keys from JSON file?

Question

JSON

There is a JSON file with no attachment, i.e. the value of each key is not an object. There are duplicate keys in this file, which JS in the form of JSON.parse ignores, but this leads to problems. I would like to find all duplicate pairs of values. How can I do that? Desirable implementation on node.js. Maybe there is an already written json linter that can do what is described above, I just could not find it.
Example:

{
    "x": 4,
    "x": 5
}

In this case, you need to deduce that the key "x" is repeated

Answer 1

this is not a valid json, so all the parsers just think for you and do "good". in fact, if you want your own logic, you will need to write your own json parser. Good luck with this.