We were spuriously reframing the <shadow> because it initially shared style with
the <br>, which ended up being display: none, while the <shadow> should've been
display: contents from the beginning.
lookup_by_rules seems pretty prone to obscure bugs, and also it's pretty
complex... Probably we should try to get rid of it, I'm unconvinced that it's
worth it.
Even with that, in a normal restyle the <details> wouldn't have ended up with a
style. It of course never had it before the reframe because the <shadow> was
display: none, but that doesn't mean it shouldn't have gotten one, since we
detected we needed to go through kids in:
https://searchfox.org/mozilla-central/rev/6eea08365e7386a2b81c044e7cc8a3daa51d8754/servo/components/style/matching.rs#500
That code did happen, but since it's an animation-only restyle, we don't look at
unstyled stuff.
That looks somewhat fishy, but I guess for now it's fine as long as display
isn't animatable.
Bug: 1469076
Reviewed-by: heycam
MozReview-Commit-ID: B6NMSTNOKgK
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
This is in preparation of a cascade optimization for custom properties.
This fixes various fishiness around our StyleBuilder stuff. In particular,
StyleBuilder::for_derived_style (renamed to for_animation) is only used to
compute specified values, and thus doesn't need to know about rules, visited
style, or other things like that.
The flag propagation that was done in StyleAdjuster is now done in StyleBuilder,
since we know beforehand which ones are always inherited, and it simplified the
callers and the StyleAdjuster code. It also fixed some fishiness wrt which flags
were propagated to anon boxes and text.
The text-decoration-lines bit is interesting, because the way it was implemented
in #17722 meant that display: contents elements did get HAS_DECORATION_LINES
flags only if its parent also had it, so in practice the Contents check
preserves behavior, but it's only an optimization looking at Gecko's call-sites,
so we can remove it too.
MozReview-Commit-ID: 6BHCyEO2U8c
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.
It is bogus, because it depends on the display property as it's cascaded, but
the display property can change afterwards, for example, if we get blockified
because we're the root element or a flex item.
Replace it with a normal field instead.
Also, it carries some weight, because it's the last property that uses this
concept of "derived" property, and "custom cascade". So we can remove some code
after this.
Compute it after the cascade process in StyleAdjuster.
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.
The style adjuster knows about the pseudo, so there's no reason to thread that
info down.
There are more simplifications that can be done in followups, cleaning a bit the
cascade flags too, those will come later.
Fixes warnings from rust-lang/rust#44229 when `--enable-commonmark` is
passed to rustdoc.
This is mostly a global find-and-replace for bare URIs on lines by
themselves in doc comments.
Add values::computed::NonNegativeAu, so BorderSideWith could be computed
to this non-negative Au, for the following properties:
1. outline-width
2. border-{*}-width
3. column-rule-width
4. -webkit-text-stroke-width
MozReview-Commit-ID: ASHaB2F7VtM
Unfortunately this means that we lose the NS_STYLE_INHERIT_BIT optimization to
avoid posting changes if we had not requested the struct. In practice, I'm not
sure this optimization matters much, though, and we already compare all the
structs anyway.
We _could_ keep a weak parent pointer from the text style if needed, given we're
going to keep alive the text style at least until the parent style context goes
away, so should be safe, but I don't think the extra churn is worth it, to be
honest. Happy to do so as part of bug 1368290 if you think it's worth it.
Bug: 1385896
Reviewed-by: heycam
MozReview-Commit-ID: ka6tNwf4Ke
The concept of inherited style is about to get a bit more complicated, and this
will prevent consumers from doing it wrong.
Part 1 of Gecko bug1382806. r=emilio