refactor defineProperty usage

[ronag]

I've noticed that there is a lot of strange usage of `defineProperty" through the code base with slightly inconsistent options/configurations.

I don't mind helping out with this but I would need some help understanding the rules/thoughts behind some of these.

Furthermore if any of them need special configuration we should probably add tests for those...

[ronag]

#28934 (comment)

[bnoordhuis]

Happy to provide input but can you phrase it as closed questions? ^^

[ronag]

Happy to provide input but can you phrase it as closed questions? ^^

Sorry, I don't understand?

[bnoordhuis]

Can you point to examples and explain what's unclear? The way your OP is phrased makes it kind of hard now to know where to start.

[ronag]

https://github.com/nodejs/node/search?q=defineProperty%28+-path%3Adeps+-path%3Atest&unscoped_q=defineProperty%28+-path%3Adeps+-path%3Atest

In particular the configuration of enumerable and configurable is unclear.

http seems to like to set enumerable: true and configurable: true with no defined reasoning: https://github.com/nodejs/node/blob/master/lib/_http_outgoing.js#L552

Likewise buffer seems to have some extra configuration that seems unclear: https://github.com/nodejs/node/blob/master/lib/buffer.js

[bnoordhuis]

I think most of those can be explained by the words "backwards compatibility."

E.g. buffer.parent used to be an enumerable data property, now it's a getter. It makes no sense to redefine it (it'd be unsafe), hence it's non-configurable.

I don't know why outgoing.headersSent is configurable but it's probably for compatibility. It's enumerable because it was enumerable when it was still a simple data property.