Before this change, the `ComputedStyle` struct that is part of permanent style
data per element holds 2 `StrongRuleNode`s (unvisited and visited) and 2
`Arc<ComputedValues>` (unvisited and visited).
Both rule nodes and the visited values don't actually need to be here. This
patch moves these 3 to new temporary storage in `CascadeInputs` on
`CurrentElementInfo` during the match and cascade process. Rule nodes are
pushed down inside the `ComputedValues` for later access after the cascade.
(Visited values were already available there.)
The permanent style data per element now has just the `Arc<ComputedValues>` for
itself and eager pseudo-elements (plus the `RestyleHint`).
MozReview-Commit-ID: 3wq52ERMpdi
Right now when calling getComputedStyle with an element from another document,
we return the style using the pres context of that document, not of the document
of the window getComputedStyle was called on, so this holds.
But it will stop holding if we ever change this, so assert it doesn't happen.
Bug: 1374062
Reviewed-By: Manishearth
MozReview-Commit-ID: 3g8yQWWdsen
Before this commit, we assumed that if the element had no parent element, it was
the root of the document, which is plain false, since we can arrive there from,
let's say, getComputedStyle on a detached node.
Bug: 1374062
Reviewed-By: heycam
MozReview-Commit-ID: 65DxdzXgd0J
Otherwise, tests like the following fail, given we always match as unvisited,
and we'd never mark the link as needing invalidation.
<!doctype html>
<style>
a {
color: red !important;
}
.foo :visited {
color: green !important;
}
</style>
<div>
<a href="https://google.es">visit me</a>
<button onclick="this.parentNode.className = 'foo'">Then click me</button>
</div>
Bug: 1368240
MozReview-Commit-ID: LDv6S28c4ju
This commit also removes the old restyle_hints module and splits it into
multiple modules under components/style/invalidation/element/.
The basic approach is to walk down the tree using compound selectors as needed,
in order to do as little selector-matching as possible.
Bug: 1368240
MozReview-Commit-ID: 2YO8fKFygZI
This patch renames TNode::parent_element to traversal_parent, since it returns
the parent from the perspective of traversal (which in Gecko uses the
flattened tree). It also renames TNode::children to traversal_children
for the saem reason.
We keep parent_element and children functions on TNode to use for selector
matching, which must be done on the real DOM tree structure.
We can have cousins in the cache whose parent doesn't match ours, and other
cousins whose parent does. When we encounter one of the former, that's not a
reason to stop lookin for the latter.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1369620
Also, do nothing for now (we'll hook the Gecko pieces here when the time comes).
Let me know if you want to hold-off landing this.
MozReview-Commit-ID: 6PIhfp6sxk4
Speed up the visited cascade by only running it for the properties that are
actually visited dependent. (These are only the properties where the separate
set of visited styles is even read at all, so running the rest is wasted work.)
MozReview-Commit-ID: 5B7wYtuH974
To support visited styles, we match and cascade a separate set of styles any
time we notice that an element has a relevant link.
The visited rules and values are held in `ComputedStyle` alongside the
regular rules and values, which simplifies supporting various APIs like
`cascade_primary_and_pseudos` which expect easy access to previously matched
rules.
To simplify passing the additional values around, an additional reference to the
visited `ComputedValues` is placed inside the regular `ComputedValues`.
MozReview-Commit-ID: 2ebbjcfkfWf
We only use whether the return value is IMPORTANT_RULES_CHANGED or not, so we
can just return true if an important rules was changed in the function.
Also, we can just return false in case of animation rules changes sine for
animation we can ensure there is no importan rules.
Because of these changes, replace_rule_node does not borrow |result| so that
we can drop a scope there.
In the case where we process an element which has SMIL animations in normal travesal
the SMIL styles must have been computed in animation-only restyles. So we
have only to pick the computed styles instead of recomputing it.
Stylist accessors
<!-- Please describe your changes on the following line: -->
Add accessor methods for the `device` and `ruleset` fields in the `Stylist` struct.
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