This allows servo to use the ExternalScrollId API from WebRender fixing
some issues related to duplicate scroll root ids.
Fixes#17176.
Fixes#19287.
Fixes#19648.
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This makes an element available in StyleAdjuster, and uses it to replace some of our CascadeFlags (the ones that don't represent restrictions on what's actually cascaded, actually).
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.
See each commit for details.
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It's kind of a mess. See individual commits for details.
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All TElement's implement Copy, and are just pointers, so the double indirection
is stupid.
I'm going to try to see if removing this double-indirection fixes some
selector-matching performance, and this is a trivial pre-requisite while I wait
for Talos results.
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Replace them instead by a computed value flag, the same way as the
IS_IN_DISPLAY_NONE_SUBTREE flag works.
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style: Make all keywords CamelCase for consistency.
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This is not really an useful abstraction, and I never knew how to spell it.
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This is the Servo side change of [bug 1397644](https://bugzilla.mozilla.org/show_bug.cgi?id=1397644).
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style: Stop threading the ElementData around the invalidator.
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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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Automatically verify that derive() lists are alphabetically ordered #18172
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The `stylearc` alias is left there temporarilly and will be removed completely in a later commit/PR where also `components/style/gecko/generated/structs_{debug|release}.rs` are re-generated (they still use the old alias).
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This allows us to have ensure_data() and clear_data() functions on the TElement
trait, instead of hacking around it adding methods in random traits.
This also allows us to do some further cleanup, which I'd rather do in a
followup.
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rename : servo/components/script/layout_wrapper.rs => servo/components/layout_thread/dom_wrapper.rs
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It's trivial to do so after #17688.
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Reviewed by @emilio in https://bugzilla.mozilla.org/show_bug.cgi?id=1352669.
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This is part of #16982.
Right now we have some code that tries to cache stuff in the style data during
layout.
This code is extremely rarely executed, only for `<details>` and `<summary>`.
I think if we really really want to cache these, we should find a place in the
layout data for it.
For now, let's move it away (and all the other layout code) from mutating the
style data from layout.
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On top of https://github.com/servo/servo/pull/16890.
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Now that script has `WindowProxy` rather than `BrowsingContext` objects, we can rename `Frame` in the constellation to `BrowsingContext`. In particular, this means that `FrameId`s are now `BrowsingContextid`s, which better captures their purpose (and they are used in a lot of places, not just the constellation).
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Just use WebRender's ClipId directly. This will allow us to create and
use ReferenceFrames in the future, if we need to do that. It will also
make it easier to have Servo responsible for creating the root
scrolling area, which will allow removing some old hacks in the future.
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Use some fake pseudo elements to style servo-specific boxes in servo. Also, Since for nested inline elements non-inheritable properties are properly stored in the inline context of an inline fragment, so get
rid of them on the style using empty pseudo to do cascading.
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Before this PR, every object reflected in CSSOM is in `Arc<RwLock<_>>` to enable safe (synchronized) mutable aliasing. Acquiring all these locks has significant cost during selector matching:
* https://bugzilla.mozilla.org/show_bug.cgi?id=1311469
* https://bugzilla.mozilla.org/show_bug.cgi?id=1335941
* https://bugzilla.mozilla.org/show_bug.cgi?id=1339703
This PR introduce a mechanism to protect many objects with the same `RwLock` that only needs to be acquired once.
In Stylo, there is one such lock per process (in a `lazy_static`), used for everything.
I non-Stylo Servo, I originally intended to have one such lock per document (for author-origin stylesheets, and one per process for user-agent and user sytlesheets since they’re shared across documents, and never mutated anyway). However I failed to have the same document-specific (or pipeline-specific) `Arc` reachable from both `Document` nodes and `LayoutThread`. Recursively following callers lead me to include this `Arc` in `UnprivilegedPipelineContent`, but that needs to be serializable. So there is a second process-wide lock.
This was previously #15998, closed accidentally.
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This is on top of https://github.com/servo/servo/pull/15928.
Now that cascade() gets a Device ref, we can use the default computed values
from there to avoid propagating that state all over the place.
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This is needed for https://bugzilla.mozilla.org/show_bug.cgi?id=1346481
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Discussion and review in https://bugzilla.mozilla.org/show_bug.cgi?id=1336646
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When we resolve style for an eagerly computed pseudo-element, such as an anonymous box, if there are no matching rules we currently just clone the parent's style. We should only do that if `inherit_all` is true, otherwise we should inherit only the inherited properties from the parent.
I was going to use `.unwrap_or_default()` on the result of looking up `precomputed_pseudo_element_decls`, but that didn't seem to work since that map lookup returns a reference and not a `Vec` itself.
r? @emilio
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This is part of the fix for #11297. This PR fixes the inline layout of table cells impacted by row-spanning cells from previous rows. A separate PR to follow will fix the table block size calculations to account for rowspan.
This PR doesn't yet include any test changes. If it doesn't cause any existing tests to pass, I will add a new test to it.
r? @pcwalton
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The primary idea of this patch is to ditch the rigid enum of Previous/Current
styles, and replace it with a series of indicators for the various types of
work that needs to be performed (expanding snapshots, rematching, recascading,
and damage processing). This loses us a little bit of sanity checking (since
the up-to-date-ness of our style is no longer baked into the type system), but
gives us a lot more flexibility that we'll need going forward (especially when
we separate matching from cascading). We also eliminate get_styling_mode in
favor of a method on the traversal.
This patch does a few other things as ridealongs:
* Temporarily eliminates the handling for transfering ownership of styles to the
frame. We'll need this again at some point, but for now it's causing too much
complexity for a half-implemented feature.
* Ditches TRestyleDamage, which is no longer necessary post-crate-merge, and is
a constant source of compilation failures from either needing to be imported
or being unnecessarily imported (which varies between gecko and servo).
* Expands Snapshots for the traversal root, which was missing before.
* Fixes up the skip_root stuff to avoid visiting the skipped root.
* Unifies parallel traversal and avoids spawning for a single work item.
* Adds an explicit pre_traverse step do any pre-processing and determine whether
we need to traverse at all.
Source-Repo: https://github.com/servo/servo
Source-Revision: b9a8ccd775c3192e3810a1730b1d0bc2b5c9dfb6
<!-- Please describe your changes on the following line: -->
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#13736, #10753 (github issue number if applicable).
<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____
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This reimplemntation of the feature uses ScrollRootIds to scroll
particular scrollable areas of the page.
Fixes#13736.
Fixes#10753.
Source-Repo: https://github.com/servo/servo
Source-Revision: a0619688a638b322f17d2034e0309502af1a5e52
