Although the flex algorithm as specified does say to determine the cross
size of the flex container, this is not how our layout engine works.
The parent formatting context is responsible for sizing its children,
and since that's already happening, we can simply remove the cross
sizing step from FFC.
If a box has definite width and a preferred aspect ratio, we can
determine its height without performing layout. Hence, its height should
also be considered definite. And the other way around for width from
height as well.
This is preparation for the next commit, which will make flex layout
relinquish control of the flex container cross size to the parent
formatting context.
This way we can just leave it alone if the property hasn't changed.
Notably, if the play-state property has been set to 'paused', and then
the user gets the animation with JS and calls .play() on it, it should
start playing despite the play-state property value.
We were off-by-one when returning the result of parsing a quoted string
in Web::Fetch::Infrastructure::collect_an_http_quoted_string. Instead of
backtracking the lexer and consuming the backtracked string, do a simple
substring operation.
Since the introduction of `AbortSignal::any()`, the specification says
`AbortSignal::create_dependent_abort_signal()` should be used where
`AbortSignal::follow` was previously.
We don't want to always invoke the .play() method if an animation is
relevant and had a play state of running, as the play state is
essentially just "paused" or "not paused". We replace that relevancy
check with the inverse of the pause check so we don't constantly call
.play() on animations that are finished.
Also duplicates and moves the temporary context into both blocks, since
most of the time neither condition will be true.
Rather than trying to store a Handle to a WebIDL::BufferSource, let's
look ahead to what the spec wants us to do with this field and get a
copy of the bytes held by the buffer source right away.
This is a fetching AO and is only used by LibWeb in the context of fetch
tasks. Move it to LibWeb with other fetch methods.
The main reason for this is that it requires the use of other LibWeb AOs
such as the forgiving Base64 decoder and MIME sniffing. These AOs aren't
available within LibURL.
Fixes delayed repainting in the following case:
1. Style or layout invalidation triggers html event loop processing.
2. Event loop processing does nothing because there is no rendering
opportunity.
3. Style or layout change won't be reflected until something else
triggers event loop processing
The spec for each of these state:
-> EOF:
This is an eof-in-comment parse error. Emit the current comment
token. Emit an end-of-file token.
We were neglecting to emit the current comment token before emitting an
EOF token. Note the existing EMIT_CURRENT_TOKEN macro was unused.
If box is sized as replaced it still could be anything, not only SVG.
This fixes crashing on https://www.shopify.com/ that was caused by a
missing paintable for a box that has a layout node. This occurred
because the box was not laid out in dimension_box_on_line().
`Node::shadow_including_root()` was missing a null check, which caused
a crash when manipulating a select element, whose option elements were
initially detached.
The HTMLMediaElement, for example, contains spec text which states any
ongoing fetch process must be "stopped". The spec does not indicate how
to do this, so our implementation is rather ad-hoc.
Our current implementation may cause a crash in places that assume one
of the fetch algorithms that we set to null is *not* null. For example:
if (fetch_params.process_response) {
queue_fetch_task([]() {
fetch_params.process_response();
};
}
If the fetch process is stopped after queuing the fetch task, but not
before the fetch task is run, we will crash when running this fetch
algorithm.
We now track queued fetch tasks on the fetch controller. When the fetch
process is stopped, we cancel any such pending task.
It is a little bit awkward maintaining a fetch task ID. Ideally, we
could use the underlying task ID throughout. But we do not have access
to the underlying task nor its ID when the task is running, at which
point we need some ID to remove from the pending task list.
...because "change" event should be dispatched on control even if it
has "display: none" style.
This change fixes selection in labels dropdown on GitHub's "new issue"
page.
Given a selector like `.foo .bar #baz`, we know that elements with
the class names `foo` and `bar` must be present in the ancestor chain of
the candidate element, or the selector cannot match.
By keeping track of the current ancestor chain during style computation,
and which strings are used in tag names and attribute names, we can do
a quick check before evaluating the selector itself, to see if all the
required ancestors are present.
The way this works:
1. CSS::Selector now has a cache of up to 8 strings that must be present
in the ancestor chain of a matching element. Note that we actually
store string *hashes*, not the strings themselves.
2. When Document performs a recursive style update, we now push and pop
elements to the ancestor chain stack as they are entered and exited.
3. When entering/exiting an ancestor, StyleComputer collects all the
relevant string hashes from that ancestor element and updates a
counting bloom filter.
4. Before evaluating a selector, we first check if any of the hashes
required by the selector are definitely missing from the ancestor
filter. If so, it cannot be a match, and we reject it immediately.
5. Otherwise, we carry on and evaluate the selector as usual.
I originally tried doing this with a HashMap, but we ended up losing
a huge chunk of the time saved to HashMap instead. As it turns out,
a simple counting bloom filter is way better at handling this.
The cost is a flat 8KB per StyleComputer, and since it's a bloom filter,
false positives are a thing.
This is extremely efficient, and allows us to quickly reject the
majority of selectors on many huge websites.
Some example rejection rates:
- https://amazon.com: 77%
- https://github.com/SerenityOS/serenity: 61%
- https://nytimes.com: 57%
- https://store.steampowered.com: 55%
- https://en.wikipedia.org: 45%
- https://youtube.com: 32%
- https://shopify.com: 25%
This also yields a chunky 37% speedup on StyleBench. :^)
