freeCodeCamp: Challenge (Use the .env File) delete the property instead of setting it to undefined

Technically, if we are testing for a non-existing property we can’t set process.env.MESSAGE_STYLE to undefined as that is implicitly converted to a string.

process.env

Assigning a property on process.env will implicitly convert the value to a string.

This means you can’t use this logic

// process.env.MESSAGE_STYLE = 'uppercase'

let message = process.env.MESSAGE_STYLE ? {"message": "HELLO JSON"} : {"message": "Hello json"}

console.log(message) // { message: 'HELLO JSON' }

process.env.MESSAGE_STYLE = undefined;
console.log(typeof process.env.MESSAGE_STYLE) // string

message = process.env.MESSAGE_STYLE ? {"message": "HELLO JSON"} : {"message": "Hello json"}
console.log(message) // { message: 'HELLO JSON' }

But if you delete it, it works.

delete process.env.MESSAGE_STYLE
message = process.env.MESSAGE_STYLE ? {"message": "HELLO JSON"} : {"message": "Hello json"}
console.log(message) // { message: 'Hello json' }

The forum thread that made me open this issue:

https://forum.freecodecamp.org/t/use-the-end-file/498485

---

Challenge: https://www.freecodecamp.org/learn/back-end-development-and-apis/basic-node-and-express/use-the--env-file

Test: https://github.com/freeCodeCamp/fcc-express-bground-pkg/blob/master/index.js