xs throws GeneratorFunction.__proto__ was not Function.prototype.constructor

Does this mean xs is non-conforming? Or just that it’s not a platform that this code knows about?

https://github.com/Agoric/harden/blob/0a5185ee224b98e75623a2f88143d118e0849eaa/src/anonIntrinsics.js#L230

for reference, my main.js:

import harden from '@agoric/harden';

export default function main() {
  trace("hi there\n");
  const h = harden({});
  trace("harded:", String(h), "\n");
}

and my manifest.json:

{
  "include": [
    "$(MODDABLE)/examples/manifest_base.json",
  ],
  "modules": {
    "*": [
      "./main",
    ],
    "@agoric/make-hardener": "./node_modules/@agoric/make-hardener/index",
    "@agoric/harden": "./node_modules/@agoric/harden/dist/harden.esm",
  },
}

[phoddie]

We’ll post a change to the Moddable SDK in the coming days to address this. Meanwhile you can apply it locally by adding the following line…

slot->value.instance.prototype = mxFunctionConstructor.value.reference;

in xsGenerator.c after lines 72 and 97.

Patrick notes:

It is important that to understand the difference between executing code at link time and at run time. At link time, when vetted modules are preloaded, the prototype chains conform. Then the XS linker modify the prototype chains to prevent compartments to access constructors. So at runtime the prototype chains do not conform.

We have prepared an example Gist that shows the behavior.

At link time

_Function == Function true
_AsyncFunction.__proto__ == Function true
_AsyncGeneratorFunction.__proto__ == Function true
_GeneratorFunction.__proto__ == Function true

At runtime

_Function == Function false
_AsyncFunction.__proto__ == Function false
_AsyncGeneratorFunction.__proto__ == Function false
_GeneratorFunction.__proto__ == Function false

Maybe there are other invariants to test. And other bugs to fix. The example provides a way to experiment.

[jfparadis]

This issue has been resolved in SES 2.0, the code doing the collection of intrinsics assumed that it ran in JS, not in SES.

GeneratorFunction.__proto__ was not Function.prototype.constructor`

The check now works in both modes (JS and SES) because don’t check against Function, which can be tamed, but against Function.prototype.constructor which has a different value in SES and in JS.