ladybird/Userland/Libraries/LibWeb/CSS/Supports.cpp
Sam Atkins 7bea0d501e LibWeb: Remove unknown value in @supports query logic
This is in line with this recent change to Conditional-3:

> Removed the “unknown” value in CSS feature queries’ boolean logic,
> defining unrecognized syntaxes as “false” instead.
> https://github.com/w3c/csswg-drafts/issues/6175
2022-01-19 21:44:45 +00:00

59 lines
1.3 KiB
C++

/*
* Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/CSS/Parser/Parser.h>
#include <LibWeb/CSS/Supports.h>
namespace Web::CSS {
Supports::Supports(NonnullOwnPtr<Condition>&& condition)
: m_condition(move(condition))
{
m_matches = m_condition->evaluate();
}
bool Supports::Condition::evaluate() const
{
switch (type) {
case Type::Not:
return !children.first().evaluate();
case Type::And:
for (auto& child : children) {
if (!child.evaluate())
return false;
}
return true;
case Type::Or:
for (auto& child : children) {
if (child.evaluate())
return true;
}
return false;
}
VERIFY_NOT_REACHED();
}
bool Supports::InParens::evaluate() const
{
return value.visit(
[&](NonnullOwnPtr<Condition> const& condition) {
return condition->evaluate();
},
[&](Feature const& feature) {
return feature.evaluate();
},
[&](GeneralEnclosed const&) {
return false;
});
}
bool Supports::Feature::evaluate() const
{
auto style_property = Parser({}, declaration).parse_as_declaration();
return style_property.has_value();
}
}