SyntaxError: Unexpected token ':' when JSON.stringify is overridden

Without overriding JSON.stringify, the query works fine. When JSON.stringify is overridden, I get SyntaxError: Unexpected token ':' This is the entire code.

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();
}

Start by running the complete Node.js reproduction with mysql2, including the JSON.stringify override, and inspect the connection and query path around connection.connect(), connection.query(), and connection.end(). Done means the cause of the reported SyntaxError is identified and the query no longer fails, or the incompatibility is clearly documented.