Some calls https://html.spec.whatwg.org/#set-the-ongoing-navigation could need some clarification

[mbrodesser-Igalia]

What is the issue with the HTML Standard?

https://html.spec.whatwg.org/#set-the-ongoing-navigation should "inform the navigation API about aborting navigation" only if "navigable's ongoing navigation" is not null.

It's set to null e.g. in step 2 of https://html.spec.whatwg.org/#navigate-to-a-javascript:-url.

Edit: see #10800 (comment) and #10800 (comment) for proposals.

[domenic]

Why do you think this? If we reach step 2 of https://html.spec.whatwg.org/#navigate-to-a-javascript:-url, we are aborting the ongoing navigation, and so we should inform the navigation API about it.

[mbrodesser-Igalia]

Why do you think this? If we reach step 2 of https://html.spec.whatwg.org/#navigate-to-a-javascript:-url, we are aborting the ongoing navigation, and so we should inform the navigation API about it.

Need to take a step back, there might be a preceding bug in the spec:

when step 19 of https://html.spec.whatwg.org/#navigate is invoked, "ongoing navigation" may be null.
Hence https://html.spec.whatwg.org/#set-the-ongoing-navigation would invoke its step 2, which shouldn't happen.
Or is there a mistake in the reasoning?

[domenic]

What is wrong with invoking step 2 if there's no ongoing navigation? It will do nothing in that case.

[mbrodesser-Igalia]

From an abstract point of view it's surprising that "inform the navigation API about aborting navigation" doesn't inform in that case. It's also not obvious if it does nothing. It seems it might also queue a task (which might do nothing).
So it'd be clearer to not invoke that step.

[mbrodesser-Igalia]

Based on the premise that step 2 does nothing, there is no technical issue.

[mbrodesser-Igalia]

It is additionally confusing that:

location.href = "javascript:console.log(1)";
location.href = "javascript:console.log(2)";

would set the navigationId in step 19 of https://html.spec.whatwg.org/#navigate, hinting there is an ongoing navigation, but only scheduling a task for a potential navigation in https://html.spec.whatwg.org/#navigate-to-a-javascript:-url.
So the second assignment of the javascript: URL, step 19 of https://html.spec.whatwg.org/#navigate would find a navigationId, because the first task didn't run yet and inform about cancelling that (which again presumably does nothing).

It might be clearer to pass something like "javascript-url" in step 20 of https://html.spec.whatwg.org/#navigate to a new call of https://html.spec.whatwg.org/#set-the-ongoing-navigation before queuing the navigate to a javascript: URL task and calling the current step 20 of https://html.spec.whatwg.org/#navigate as step 21.