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.
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 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.
Right now we go through a lot of hoops to see if we ever see a relevant link.
However, that information is not needed: if the element is a link, we'll always
need to compute its visited style because its its own relevant link.
If the element inherits from a link, we need to also compute the visited style
anyway.
So the "has a relevant link been found" is pretty useless when we know what are
we inheriting from.
The branches at the beginning of matches_complex_selector_internal were
affecting performance, and there are no good reasons to keep them.
I've verified that this passes all the visited tests in mozilla central, and
that the test-cases too-flaky to be landed still pass.
Update bitflags to 1.0 in every servo crate
It still needs dependencies update to remove all the other bitflags
versions.
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because it's a dependency update
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This type is a lot of complexity related to a very specific thing such as the
hover and active quirk.
Instead of that, move `nesting_level` to `MatchingContext`, and simplify all
this computing whether the quirk applies upfront, for each complex selector we
test.
This is less error-prone, and also allows simplifying more stuff in a bit.
Remove sources of panic when laying out an iframe without a nested browsing context
<!-- Please describe your changes on the following line: -->
At the moment, layout panics if it discovers an iframe without a nested browsing context. Under normal circumstances, this is reasonable, but it requires very tight synchronization between script, layout, the constellation and the compositor. In particular, if a layout is in progress when an iframe's browsing context is discarded, this can trigger panic.
This PR fixes this in two ways:
1. Making the pipeline and browsing context ids optional in layout's representation of an iframe.
2. Shutting down layout before discarding a browsing context, rather than after.
This is belt and braces.
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#17482 and #18477
- [X] These changes do not require tests because the PR is fixing a panic caused by a race condition
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This avoids grabbing the document when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
This avoids grabbing the document when values that inherit from the body,
whatever that means, aren't under the body.
In that case we'll get a semi-random value, but that's also mishandled by Gecko
anyways (and probably Blink, though haven't tested), and doesn't really make
much sense.
