Annoying display of Object <[Object: null prototype] {}>

[michaelfig]

@erights, @kriskowal:

Is there any particular reason why https://github.com/Agoric/SES-shim/blob/54e0b0c910fd19bec14f9e3ff9e556f17f952fd4/packages/ses/src/whitelist.js#L504 effectively forces Object.prototype.__proto__ = null?

This just makes printing of objects under SES extremely annoying (displays Object <[Object: null prototype] {}> { ... } under Node.js instead of just { ... }).

Shouldn't we instead have?

  '%ObjectPrototype%': {
    // 19.1.3 Properties of the Object Prototype Object
    '[[Proto]]': '%ObjectPrototype%',

[erights]

The alternative you show is an inheritance cycle, where Object.prototype.__proto__ === Object.prototype. Fortunately, this isn't even possible in JavaScript.

Other than the Object.prototype object itself, what other objects should inherit for Object.prototype that are instead inheriting from null?

[michaelfig]

Here is the behaviour that annoys me:

import 'ses';
console.log({});
lockdown();
console.log({});

I get the following:

node -r esm foo.js
{}
Object <[Object: null prototype] {}> {}

[erights]

I agree that is a problem. I've noticed that too. We need to diagnose what's causing it. I think the explanation lies elsewhere, but I do not understand it and have not experimented.

[erights]

This is waiting for us to find and fix where something in agoric-sdk associated with xsnap is overriding a constructor property by assignment. Only when that's fixed can we stop tuning Object.prototype.constructor into an accessor and fix this bug.