ladybird/Userland/Libraries/LibWeb/HTML/HTMLLabelElement.cpp
Tim Ledbetter 6bf22075ed LibWeb: Implement the HTMLLabelElement.form attribute
This returns the form element associated with the given label element's
control or null if the label has no control.
2024-05-18 11:04:04 +02:00

88 lines
3.1 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/Bindings/HTMLLabelElementPrototype.h>
#include <LibWeb/DOM/Document.h>
#include <LibWeb/HTML/FormAssociatedElement.h>
#include <LibWeb/HTML/HTMLLabelElement.h>
#include <LibWeb/Layout/Label.h>
namespace Web::HTML {
JS_DEFINE_ALLOCATOR(HTMLLabelElement);
HTMLLabelElement::HTMLLabelElement(DOM::Document& document, DOM::QualifiedName qualified_name)
: HTMLElement(document, move(qualified_name))
{
}
HTMLLabelElement::~HTMLLabelElement() = default;
void HTMLLabelElement::initialize(JS::Realm& realm)
{
Base::initialize(realm);
WEB_SET_PROTOTYPE_FOR_INTERFACE(HTMLLabelElement);
}
JS::GCPtr<Layout::Node> HTMLLabelElement::create_layout_node(NonnullRefPtr<CSS::StyleProperties> style)
{
return heap().allocate_without_realm<Layout::Label>(document(), this, move(style));
}
// https://html.spec.whatwg.org/multipage/forms.html#labeled-control
JS::GCPtr<HTMLElement> HTMLLabelElement::control() const
{
JS::GCPtr<HTMLElement> control;
// The for attribute may be specified to indicate a form control with which the caption is
// to be associated. If the attribute is specified, the attribute's value must be the ID of
// a labelable element in the same tree as the label element. If the attribute is specified
// and there is an element in the tree whose ID is equal to the value of the for attribute,
// and the first such element in tree order is a labelable element, then that element is the
// label element's labeled control.
if (for_().has_value()) {
root().for_each_in_inclusive_subtree_of_type<HTMLElement>([&](auto& element) {
if (element.id() == *for_() && element.is_labelable()) {
control = &const_cast<HTMLElement&>(element);
return TraversalDecision::Break;
}
return TraversalDecision::Continue;
});
return control;
}
// If the for attribute is not specified, but the label element has a labelable element descendant,
// then the first such descendant in tree order is the label element's labeled control.
for_each_in_subtree_of_type<HTMLElement>([&](auto& element) {
if (element.is_labelable()) {
control = &const_cast<HTMLElement&>(element);
return TraversalDecision::Break;
}
return TraversalDecision::Continue;
});
return control;
}
// https://html.spec.whatwg.org/multipage/forms.html#dom-label-form
JS::GCPtr<HTMLFormElement> HTMLLabelElement::form() const
{
auto labeled_control = control();
// 1. If the label element has no labeled control, then return null.
if (!labeled_control)
return {};
// 2. If the label element's labeled control is not a form-associated element, then return null.
if (!is<FormAssociatedElement>(*labeled_control))
return {};
// 3. Return the label element's labeled control's form owner (which can still be null).
return dynamic_cast<FormAssociatedElement*>(labeled_control.ptr())->form();
}
}