mysql2 for Node js. SyntaxError: Unexpected token ':' when JSON.stringify is overridden

Question

Without overriding JSON.stringify, the query works fine. When JSON.stringify is overridden, I get SyntaxError: Unexpected token ':'
This is the entire code. I run it with "node filename.js"

Why?

const mysql = require('mysql2');

const originalStringify = JSON.stringify;
/* without this override there is no error */
JSON.stringify = function (obj, replacer = null, space = 2) {
  return originalStringify(obj, replacer, space);
};

const connection = mysql.createConnection({
    host: 'localhost',
    port: 8889,
    user: 'root',
    password: 'root',
    database: 'flashcards'
});

try {
    connection.connect();
    connection.query('SELECT version()', function (error, results, fields) {
        if (error) throw error;
        console.log("result OK");
    });

} finally {
    connection.end();
}

When it works (by not overriding stringify and passing (results, null, 2) when stringify is called instead), the results look like this:

Query results: [
  {
    "version()": "5.7.39"
  }
]

Answer 1

Try this:

const originalStringify = JSON.stringify.bind(JSON);

The original JSON.stringify() may be using this to refer to the JSON module, and it loses the reference when you call it through another variable.

Answer 2

It seems there was an internal dependency on the default behavior of JSON.stringify in the project that will be changed to avoid this issue in the future. (https://github.com/sidorares/node-mysql2/issues/2293)