mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-04-30 16:28:48 +00:00
0c0650e60a
The basic idea is that style sheets can block script execution under some circumstances. With this commit, we now handle the simplest cases where a parser-inserted link element gets to download its style sheet before script execution continues. This improves performance on Speedometer 3 where JavaScript APIs that depend on layout results (like Element.scrollIntoView()) would get called too early (before the relevant CSS was downloaded), and so we'd perform premature layout work. This work then had to be redone after downloading the CSS anyway, wasting time. Note that our Text/input/link-re-enable-crash.html test had to be tweaked after these changes, since it relied on the old, incorrect, behavior where scripts would run before downloading CSS.
129 lines
4.2 KiB
C++
129 lines
4.2 KiB
C++
/*
|
|
* Copyright (c) 2018-2021, Andreas Kling <andreas@ladybird.org>
|
|
* Copyright (c) 2021, the SerenityOS developers.
|
|
* Copyright (c) 2024, Jamie Mansfield <jmansfield@cadixdev.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <LibWeb/Bindings/HTMLStyleElementPrototype.h>
|
|
#include <LibWeb/CSS/StyleComputer.h>
|
|
#include <LibWeb/DOM/Document.h>
|
|
#include <LibWeb/HTML/HTMLStyleElement.h>
|
|
|
|
namespace Web::HTML {
|
|
|
|
GC_DEFINE_ALLOCATOR(HTMLStyleElement);
|
|
|
|
HTMLStyleElement::HTMLStyleElement(DOM::Document& document, DOM::QualifiedName qualified_name)
|
|
: HTMLElement(document, move(qualified_name))
|
|
{
|
|
}
|
|
|
|
HTMLStyleElement::~HTMLStyleElement() = default;
|
|
|
|
void HTMLStyleElement::initialize(JS::Realm& realm)
|
|
{
|
|
Base::initialize(realm);
|
|
WEB_SET_PROTOTYPE_FOR_INTERFACE(HTMLStyleElement);
|
|
}
|
|
|
|
void HTMLStyleElement::visit_edges(Cell::Visitor& visitor)
|
|
{
|
|
Base::visit_edges(visitor);
|
|
m_style_element_utils.visit_edges(visitor);
|
|
}
|
|
|
|
void HTMLStyleElement::children_changed(ChildrenChangedMetadata const* metadata)
|
|
{
|
|
Base::children_changed(metadata);
|
|
m_style_element_utils.update_a_style_block(*this);
|
|
}
|
|
|
|
void HTMLStyleElement::inserted()
|
|
{
|
|
m_style_element_utils.update_a_style_block(*this);
|
|
Base::inserted();
|
|
}
|
|
|
|
void HTMLStyleElement::removed_from(Node* old_parent, Node& old_root)
|
|
{
|
|
m_style_element_utils.update_a_style_block(*this);
|
|
Base::removed_from(old_parent, old_root);
|
|
}
|
|
|
|
void HTMLStyleElement::attribute_changed(FlyString const& name, Optional<String> const& old_value, Optional<String> const& value, Optional<FlyString> const& namespace_)
|
|
{
|
|
Base::attribute_changed(name, old_value, value, namespace_);
|
|
|
|
if (name == HTML::AttributeNames::media) {
|
|
if (auto* sheet = m_style_element_utils.sheet())
|
|
sheet->set_media(value.value_or({}));
|
|
}
|
|
}
|
|
|
|
// https://html.spec.whatwg.org/multipage/semantics.html#dom-style-disabled
|
|
bool HTMLStyleElement::disabled()
|
|
{
|
|
// 1. If this does not have an associated CSS style sheet, return false.
|
|
if (!sheet())
|
|
return false;
|
|
|
|
// 2. If this's associated CSS style sheet's disabled flag is set, return true.
|
|
if (sheet()->disabled())
|
|
return true;
|
|
|
|
// 3. Return false.
|
|
return false;
|
|
}
|
|
|
|
// https://html.spec.whatwg.org/multipage/semantics.html#dom-style-disabled
|
|
void HTMLStyleElement::set_disabled(bool disabled)
|
|
{
|
|
// 1. If this does not have an associated CSS style sheet, return.
|
|
if (!sheet())
|
|
return;
|
|
|
|
// 2. If the given value is true, set this's associated CSS style sheet's disabled flag.
|
|
// Otherwise, unset this's associated CSS style sheet's disabled flag.
|
|
sheet()->set_disabled(disabled);
|
|
}
|
|
|
|
// https://www.w3.org/TR/cssom/#dom-linkstyle-sheet
|
|
CSS::CSSStyleSheet* HTMLStyleElement::sheet()
|
|
{
|
|
// The sheet attribute must return the associated CSS style sheet for the node or null if there is no associated CSS style sheet.
|
|
return m_style_element_utils.sheet();
|
|
}
|
|
|
|
// https://www.w3.org/TR/cssom/#dom-linkstyle-sheet
|
|
CSS::CSSStyleSheet const* HTMLStyleElement::sheet() const
|
|
{
|
|
// The sheet attribute must return the associated CSS style sheet for the node or null if there is no associated CSS style sheet.
|
|
return m_style_element_utils.sheet();
|
|
}
|
|
|
|
// https://html.spec.whatwg.org/multipage/semantics.html#contributes-a-script-blocking-style-sheet
|
|
bool HTMLStyleElement::contributes_a_script_blocking_style_sheet() const
|
|
{
|
|
// An element el in the context of a Document of an HTML parser or XML parser
|
|
// contributes a script-blocking style sheet if all of the following are true:
|
|
|
|
// FIXME: el was created by that Document's parser.
|
|
|
|
// el is either a style element or a link element that was an external resource link that contributes to the styling processing model when the el was created by the parser.
|
|
// NOTE: This is a style element, so all good!
|
|
|
|
// FIXME: el's media attribute's value matches the environment.
|
|
|
|
// FIXME: el's style sheet was enabled when the element was created by the parser.
|
|
|
|
// FIXME: The last time the event loop reached step 1, el's root was that Document.
|
|
|
|
// FIXME: The user agent hasn't given up on loading that particular style sheet yet.
|
|
// A user agent may give up on loading a style sheet at any time.
|
|
|
|
return false;
|
|
}
|
|
|
|
}
|