Fix swup cross build navigation

[garazdawi]

This PR fixes two things with SWUP.

1. It fixes so that links between apps do not have to be absolute in order to disable swup transitions. We have relative paths between apps in erlang.org and I think it makes sense for swup to only be used within a single path.
2. It fixes a bug introduced in a66397f that disables swup on any link that has an anchor.

[github-actions]

📦 Docs artifacts are ready: https://github.com/elixir-lang/ex_doc/actions/runs/27211620233/artifacts/7510038011

[josevalim]

@garazdawi couldn't the check be simpler and instead we only use swup if there is no / in the path?

[josevalim]

If we only accept things that do not have a / in it:

Suggested change

	'a[href]:not([href^="/"]):not([href^="http"]):is([href$=".html"], [href*=".html#"])'
	'a[href]:not([href*="/"]):is([href$=".html"], [href*=".html#"])'

[garazdawi]

Anchors contain / (for example https://www.erlang.org/doc/apps/kernel/file.html#list_dir/1), so that breaks local anchors.

[garazdawi]

Though having thought a bit more, maybe that is not an issue as swup is not enabled for local anchors anyway, right?

[josevalim]

Good call!

No SWUP for local anchors but we can refer to anchors across files... and we still want SWUP. So I guess we keep the LINK_SELECTOR as it is, but, when validating later, we could check that it doesn't include / instead of checking for cross build?

const href = link.getAttribute('href')
const path = href.split('#', 1)[0]
!path.includes('/')

[josevalim]

Sorry, I think there was some confusion. I am afraid we cannot do this because then it won't use SWUP when navigating from Float.html to Integer.html#foo/2?

So I think we need to have the code we have before, the difference is that isCrossBuild can be replaced by something like "noUnderscoreBeforeFragment" or similar?

[garazdawi]

I noticed as much myself. I'm working on a new fix. I thought I had it working with the pushed solution, but that turned out to be due to a stale build of Erlang/OTP docs...

[garazdawi]

Should be fixed now. Tested it on a local Erlang/OTP docs build.

[josevalim]

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