340ef361d8
Previously, `anchor()` was only resolved when it appeared bare in an inset property. We now allow it to appear anywhere inside a `calc()` tree.
82 lines
3.5 KiB
C++
82 lines
3.5 KiB
C++
/*
|
||
* Copyright (c) 2025, Tim Ledbetter <tim.ledbetter@ladybird.org>
|
||
*
|
||
* SPDX-License-Identifier: BSD-2-Clause
|
||
*/
|
||
|
||
#include <LibWeb/CSS/CalculationResolutionContext.h>
|
||
#include <LibWeb/CSS/StyleValues/AnchorStyleValue.h>
|
||
#include <LibWeb/CSS/StyleValues/CalculatedStyleValue.h>
|
||
|
||
namespace Web::CSS {
|
||
|
||
ValueComparingNonnullRefPtr<AnchorStyleValue const> AnchorStyleValue::create(
|
||
Optional<FlyString> const& anchor_name,
|
||
ValueComparingNonnullRefPtr<StyleValue const> const& anchor_side,
|
||
ValueComparingRefPtr<StyleValue const> const& fallback_value)
|
||
{
|
||
return adopt_ref(*new (nothrow) AnchorStyleValue(anchor_name, anchor_side, fallback_value));
|
||
}
|
||
|
||
AnchorStyleValue::AnchorStyleValue(Optional<FlyString> const& anchor_name,
|
||
ValueComparingNonnullRefPtr<StyleValue const> const& anchor_side,
|
||
ValueComparingRefPtr<StyleValue const> const& fallback_value)
|
||
: AbstractNonMathCalcFunctionStyleValue(Type::Anchor)
|
||
, m_properties { .anchor_name = anchor_name, .anchor_side = anchor_side, .fallback_value = fallback_value }
|
||
{
|
||
}
|
||
|
||
void AnchorStyleValue::serialize(StringBuilder& builder, SerializationMode serialization_mode) const
|
||
{
|
||
builder.append("anchor("sv);
|
||
|
||
if (anchor_name().has_value())
|
||
builder.append(anchor_name().value());
|
||
|
||
if (anchor_name().has_value())
|
||
builder.append(' ');
|
||
anchor_side()->serialize(builder, serialization_mode);
|
||
|
||
if (fallback_value()) {
|
||
builder.append(", "sv);
|
||
fallback_value()->serialize(builder, serialization_mode);
|
||
}
|
||
|
||
builder.append(')');
|
||
}
|
||
|
||
// https://drafts.csswg.org/css-anchor-position-1/#anchor-pos
|
||
RefPtr<CalculationNode const> AnchorStyleValue::resolve_to_calculation_node(CalculationContext const& calculation_context, CalculationResolutionContext const& calculation_resolution_context) const
|
||
{
|
||
if (!calculation_resolution_context.anchor_resolver)
|
||
return nullptr;
|
||
|
||
// An anchor() function representing a resolvable anchor function resolves at computed value time (using style &
|
||
// layout interleaving) to the <length> that would align the edge of the positioned boxes' inset-modified containing
|
||
// block corresponding to the property the function appears in with the specified edge of the target anchor
|
||
// element’s anchor box.
|
||
if (auto side_px = calculation_resolution_context.anchor_resolver->resolve(*this); side_px.has_value())
|
||
return NumericCalculationNode::create(Length::make_px(side_px.release_value()), calculation_context);
|
||
|
||
// If any of these conditions are false, the anchor() function computes to its specified fallback value. If no
|
||
// fallback value is specified, it makes the declaration referencing it invalid at computed-value time.
|
||
auto const& fallback_value = m_properties.fallback_value;
|
||
if (!fallback_value)
|
||
return nullptr;
|
||
|
||
// NB: The fallback value can itself be an anchor(), which is resolved when the substituted tree is simplified.
|
||
NonnullRefPtr<CalculationNode const> fallback_node = fallback_value->is_anchor()
|
||
? static_cast<NonnullRefPtr<CalculationNode const>>(NonMathFunctionCalculationNode::create(fallback_value->as_anchor(), NumericType { NumericType::BaseType::Length, 1 }))
|
||
: CalculationNode::from_style_value(*fallback_value, calculation_context);
|
||
return simplify_a_calculation_tree(fallback_node, calculation_context, calculation_resolution_context);
|
||
}
|
||
|
||
bool AnchorStyleValue::equals(StyleValue const& other) const
|
||
{
|
||
if (type() != other.type())
|
||
return false;
|
||
|
||
return m_properties == other.as_anchor().m_properties;
|
||
}
|
||
|
||
}
|