Notes for myself

[nicolo-ribaudo]

This is how the Node.js internal functions map to the modules loading algorithms:	Phase	Node.js ModuleWrap (C++)	Node.js vm.Module (JS)	Current spec algorithm
Graph fetching	ModuleWrap::Link	Module#[kLink] (called by Module#link)	n/a
Graph linking	ModuleWrap::Instantiate	Module#link	module.Link()
Graph evaluation	ModuleWrap::Evaluate	Module#evaluate	module.Evaluate()

[nicolo-ribaudo]

This is how the different engines schedule the settlement of the import() promise.

Test code (./dep.js is an empty file):

(async() => {

{
  let i = 0;
  (async () => { while (++i<1000) await Promise.resolve() })();
  await import("<invalid>").catch(() => console.log("counter after error is", i));
}

await new Promise(r => setTimeout(r, 0)); // cleanup microtask queue

{
  let i = 0;
  (async () => { while (++i<1000) await Promise.resolve() })();
  await import("./dep.js").then(() => console.log("counter after success (first time) is", i));
}

await new Promise(r => setTimeout(r, 0)); // cleanup microtask queue

{
  let i = 0;
  (async () => { while (++i<1000) await Promise.resolve() })();
  await import("./dep.js").then(() => console.log("counter after success (second time) is", i));
}

})();

Node.js:

counter after error is 11
counter after success (first time) is 1000
counter after success (second time) is 14

Deno:

counter after error is 1000
counter after success (first time) is 1000
counter after success (second time) is 1000

Firefox/Chrome (I think that they don't match the HTML spec for counter after success (second time)):

counter after error is 2
counter after success (first time) is 1000
counter after success (second time) is 1000

Safari:

counter after error is 2
counter after success (first time) is 1000
counter after success (second time) is 3

With this refactor it would be:

counter after error is **host defined**
counter after success (first time) is **host defined**
counter after success (second time) is 3

[nicolo-ribaudo]

6 fixed the divergence