test: Replace misleading test

[gibson042]

arguments objects don't have a special prototype

Ref 5c41bdc0628d69a83a1c9378e986573444f2bb1d

[naugtur]

I was aiming at showing this particular kind of hack is prevented by lockdown, because it's not obvious to everyone what the prototype of arguments is.

[kriskowal]

Perhaps it would be instructive to capture an assertion that the arguments prototype is in fact null. It is frozen by virtue of Object.isFrozen(null) === true.

On Fri, Aug 19, 2022 at 1:56 AM Zbyszek Tenerowicz @.***> wrote:

@.**** approved this pull request.

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[gibson042]

The prototype isn't null, it's Object.prototype.

[kriskowal]

Pardon, as it were!

On Fri, Aug 19, 2022 at 6:51 PM Richard Gibson @.***> wrote:

The prototype isn't null, it's Object.prototype.

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[naugtur]

^ I'd say that adds grounds to my claim that we need to demonstrate arguments.proto is frozen regardless of what you think it is.

[gibson042]

What's special about arguments objects? %Object.prototype% is used as the prototype for many other built-in objects as well:

• Property descriptors from Reflect.getOwnPropertyDescriptor and Object.getOwnPropertyDescriptor{,s} (and also the object from Object.getOwnPropertyDescriptor that contains the property descriptors).
• Iteration result objects from every built-in iterator, including userland generators.
• Promise settlement objects from Promise.allSettled.
• Revocable proxy objects (i.e., assert(Object.getPrototypeOf(Proxy.revocable({}, {})) === Object.prototype)).
• Destructure-rest objects (i.e., { ...rest } = {}; assert(Object.getPrototypeOf(rest) === Object.prototype)).
• The prototype of function/class prototypes (i.e., assert(Object.getPrototypeOf(Object.getPrototypeOf(new class {})) === Object.prototype)).
• etc.

[naugtur]

The only thing that's special is the number of people knowing JS very well that were unsure what's the prototype of arguments. I have this occasional itch to document surprising stuff with tests if not too time consuming. But I'm not orthodox about it ;)