Currently, NAC always inherits from the closest non-NAC ancestor element,
regardless of whether it is for an element-backed pseudo or not.
This patch changes the inheritance so that for element-backed pseudos, we
inherit from the closest native anonymous root's parent, and for other NAC we
inherit from the parent.
This prevents the following two issues and allows us to remove the
NODE_IS_NATIVE_ANONYMOUS flag:
* Avoiding inheriting from the non-NAC ancestor in XBL bindings bound to NAC.
- This is no longer a problem since we apply the rule only if we're a
pseudo-element, and all pseudo-elements are in native anonymous subtrees.
- This also allows to remove the hack that propagates the
NODE_IS_NATIVE_ANONYMOUS flag from the ::cue pseudo-element from
BindToTree.
* Inheriting from the wrong thing if we're a nested NAC subtree.
- We no longer look past our NAC subtree, with the exception of
::-moz-number-text's pseudo-elements, for which we do want to propagate
::placeholder to.
A few rules from forms.css have been modified because they're useless or needed
to propagate stuff to the anonymous form control in input[type="number"] which
previously inherited from the input itself.
Bug: 1460382
Reviewed-by: heycam
MozReview-Commit-ID: IDKYt3EJtSH
Pretty much the same setup we have for document.
We have the awkwardness of having to check containing shadow manually for
ShadowRoot because it's not available in TNode (and making it available added a
bit more complexity that wasn't worth it IMO).
Bug: 1464428
Reviewed-by: xidorn
MozReview-Commit-ID: CqOh0sLHf6o
This also adopts the resolution of [1] while at it, and switches XUL to not
support display: contents until a use case appears.
This makes our behavior consistent both with the spec and also in terms of
handling dynamic changes to stuff that would otherwise get suppressed.
Also makes us consistent with both Blink and WebKit in terms of computed style.
We were the only ones respecting "behaves as display: none" without actually
computing to display: none. Will file a spec issue to get that changed.
It also makes us match Blink and WebKit in terms of respecting display: contents
before other suppressions, see the reftest which I didn't write as a WPT
(because there's no spec supporting neither that or the opposite of what we do),
where a <g> element respects display: contents even though if it had any other
kind of display value we'd suppress the frame for it and all the descendants
since it's an SVG element in a non-SVG subtree.
Also, this removes the page-break bit from the display: contents loop, which I
think is harmless.
As long as the tests under style are based in namespace id / node name /
traversal parent, this should not make style sharing go wrong in any way, since
that's the first style sharing check we do at [2].
The general idea under this change is making all nodes with computed style of
display: contents actually honor it. Otherwise there's no way of making the
setup sound except re-introducing something similar to all the state tracking
removed in bug 1303605.
[1]: https://github.com/w3c/csswg-drafts/issues/2167
[2]: https://searchfox.org/mozilla-central/rev/fca4426325624fecbd493c31389721513fc49fef/servo/components/style/sharing/mod.rs#700
Bug: 1453702
Reviewed-by: mats, xidorn
MozReview-Commit-ID: JoCKnGYEleD
We could invalidate in a slightly more fine-grained way, but I don't think it's
worth the churn vs. keeping the special-cases minimal.
Bug: 1452640
Reviewed-by: xidorn
MozReview-Commit-ID: 5DkQrgwg9GW
Kinda tricky because :host only matches rules on the shadow root where the rules
come from. So we need to be careful during invalidation and style sharing.
I didn't use the non_ts_pseudo_class_list bits because as soon as we implement
the :host(..) bits we're going to need to special-case it anyway.
The general schema is the following:
* Rightmost featureless :host selectors are handled inserting them in the
host_rules hashmap. Note that we only insert featureless stuff there. We
could insert all of them and just filter during matching, but that's slightly
annoying.
* The other selectors, like non-featureless :host or what not, are added to the
normal cascade data. This is harmless, since the shadow host rules are never
matched against the host, so we know they'll just never match, and avoids
adding more special-cases.
* Featureless :host selectors to the left of a combinator are handled during
matching, in the special-case of next_element_for_combinator in selectors.
This prevents this from being more invasive, and keeps the usual fast path
slim, but it's a bit hard to match the spec and the implementation.
We could keep a copy of the SelectorIter instead in the matching context to
make the handling of featureless-ness explicit in match_non_ts_pseudo_class,
but we'd still need the special-case anyway, so I'm not fond of it.
* We take advantage of one thing that makes this sound. As you may have
noticed, if you had `root` element which is a ShadowRoot, and you matched
something like `div:host` against it, using a MatchingContext with
current_host == root, we'd incorrectly report a match. But this is impossible
due to the following constraints:
* Shadow root rules aren't matched against the host during styling (except
these featureless selectors).
* DOM APIs' current_host needs to be the _containing_ host, not the element
itself if you're a Shadow host.
Bug: 992245
Reviewed-by: xidorn
MozReview-Commit-ID: KayYNfTXb5h
This adds TShadowRoot to the `dom` module.
Right now it barely adds uses of it, but this is a prerequisite to fix a bunch
of Shadow DOM bugs and separate it from the XBL mess.
It's just a struct aggregating stylesheets + CascadeData, with a quirks_mode
parameter because XBL sucks so bad.
Bug: 1436059
Reviewed-by: xidorn
MozReview-Commit-ID: 7q99tSNXo0K
Now that we have an Element around on cascade, we can stop using the cascade
flags mechanism to pass various element-related state, like "is this element the
root", or "should it use the item-based display fixup".
That fixes handwaviness in the handling of those flags from style reparenting,
and code duplication to handle tricky stuff like :visited.
There are a number of other changes that are worth noticing:
* skip_root_and_item_based_display_fixup is renamed to skip_item_display_fixup:
TElement::is_root() already implies being the document element, which by
definition is not native anonymous and not a pseudo-element.
Thus, you never get fixed-up if your NAC or a pseudo, which is what the code
tried to avoid, so the only fixup with a point is the item one, which is
necessary.
* The pseudo-element probing code was refactored to return early a
Option::<CascadeInputs>::None, which is nicer than what it was doing.
* The visited_links_enabled check has moved to selector-matching time. The rest
of the checks aren't based on whether the element is a link, or are properly
guarded by parent_style.visited_style().is_some() or visited_rules.is_some().
Thus you can transitively infer that no element will end up with a :visited
style, not even from style reparenting.
Anyway, the underlying reason why I want the element in StyleAdjuster is because
we're going to implement an adjustment in there depending on the tag of the
element (converting display: contents to display: none depending on the tag), so
computing that information eagerly, including a hash lookup, wouldn't be nice.
This is a partial revert of
ce1d8cd232
If you're in a shadow tree, you may not be slotted but you still need to look at
the slotted rules, since a <slot> could be a descendant of yours.
Just use the same invalidation map everywhere, and remove complexity.
This means that we can do some extra work while trying to gather invalidation
if there are slotted rules, but I don't think it's a problem.
The test is ported from https://cs.chromium.org/chromium/src/third_party/WebKit/LayoutTests/fast/css/invalidation/slotted.html?l=1&rcl=58d68fdf783d7edde1c82a642e037464861f2787
Curiously, Blink fails the test as written, presumably because they don't flush
styles from getComputedStyle correctly (in their test they do via
updateStyleAndReturnAffectedElementCount), due to <slot>s not being in the flat
tree in their implementation.
Bug: 1429846
Reviewed-by: heycam
MozReview-Commit-ID: 6b7BQ6bGMgd
This reverts commit 1970e82b0d, reversing
changes made to e882660ea6.
The reparenting logic is still bogus, but I'll figure out how to deal with that
in a bit.
In practice the only NAC that possibly inherits from a grid or flex container
are pseudos.
In Gecko, if the root element is an item container, custom anon content would
also sometimes incorrectly inherit from that (see bug 1405635), but that's fixed
in Stylo.
We remove the IS_ROOT_ELEMENT blockification from the "skip display fixup"
check, since the root element is never NAC or anything like that, so there's no
need for the check.
This also fixes some reparenting fishiness related to pseudo-elements. We were
only skipping the fixup when reparenting anon boxes, not when reparenting normal
element styles, nor when reparenting other pseudo styles which are not anon
boxes.
style: Get rid of unstyled children only traversals.
They're useless now, provided we remove the hack to not traverse XBL-bound
elements on initial styling.
Bug: 1418456
Reviewed-by: heycam
MozReview-Commit-ID: AvBVdyF1wb6
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They're useless now, provided we remove the hack to not traverse XBL-bound
elements on initial styling.
Bug: 1418456
Reviewed-by: heycam
MozReview-Commit-ID: AvBVdyF1wb6
The code that uses it is of dubious utility, fwiw, but some of it is used on
Servo, so I'll kill that separately.
Bug: 1412486
Reviewed-by: xidorn
MozReview-Commit-ID: KauvXX32zLM
