1404916 - nsContentIterator is used over anonymous content

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, enhancement, P3)

Description

[Cătălin Badea (:catalinb)]

This is a follow-up for bug 1395973. nsFind will initialize nsContentIterator with anonymous endpoints, but we can't really iterate over it. This currently works out of luck. It would be nice fix this and maybe stop using (node, offset) for initializing nsContentIterator.

Comment 1

[Markus Stange [:mstange]]

This shows up in the profiles from bug 1844470: ContentIteratorBase::GetNextSibling spends much of its time in this check:

https://searchfox.org/mozilla-central/rev/6e2fb6cde8ba14b9d9a6367ba61a97ad1f13b1c2/dom/base/ContentIterator.cpp#626-631

// XXX This is a hack to preserve previous behaviour: This should be fixed
// in bug 1404916. If we were positioned on anonymous content, move to
// the first child of our parent.
if (parent->GetLastChild() && parent->GetLastChild() != aNode) {
  return parent->GetFirstChild();
}

Emilio, do you know what to do with this bug?

Comment 2

[Markus Stange [:mstange]]

Attachment: profiler screenshot

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Hard to know off-hand without knowing what fails without it, but at the very least we should be able to replace that check by something faster. Just sent a patch to bug 1849838 doing that. Will send a try run removing it and see what blows up. Comment 0 mentions nsFind but nsFind no longer uses ContentIterator. So maybe it can just go?

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1404916 - Remove ContentIterator native-anonymous hack. r=smaug,mstange

Comment 0 mentions nsFind but nsFind no longer uses this code. So let's
try to remove this.

Comment 5

[Emilio Cobos Álvarez (:emilio)]

Looks green? https://treeherder.mozilla.org/jobs?repo=try&revision=5bd239722f17478064517d1c8249097e450adf13

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2303dc7d7757
Remove ContentIterator native-anonymous hack. r=smaug

Comment 7

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/2303dc7d7757