chromium/third_party/blink/renderer/core/layout/list/unpositioned_list_marker.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LIST_UNPOSITIONED_LIST_MARKER_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LIST_UNPOSITIONED_LIST_MARKER_H_

#include <optional>

#include "base/dcheck_is_on.h"
#include "base/memory/scoped_refptr.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/layout/geometry/box_strut.h"
#include "third_party/blink/renderer/platform/fonts/font_baseline.h"
#include "third_party/blink/renderer/platform/heap/garbage_collected.h"
#include "third_party/blink/renderer/platform/heap/member.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"

namespace blink {

class BlockNode;
class BoxFragmentBuilder;
class ComputedStyle;
class ConstraintSpace;
class LayoutOutsideListMarker;
class LayoutResult;
class PhysicalFragment;

// Represents an unpositioned list marker.
//
// A list item can have either block children or inline children. Because
// BLockLayoutAlgorithm handles the former while InlineLayoutAlgorithm
// handles the latter, list marker can appear in either algorithm.
//
// To handle these two cases consistently, when list markers appear in these
// algorithm, they are set as "unpositioned", and are propagated to ancestors
// through LayoutResult until they meet the corresponding list items.
//
// In order to adjust with the other content of LI, marker will be handled
// after other children.
// First, try to find the alignment-baseline for the marker. See
// |ContentAlignmentBaseline()| for details.
// If found, layout marker, compute the content adjusted offset and float
// intuded offset. See |AddToBox()| for details.
// If not, layout marker and deal with it in |AddToBoxWithoutLineBoxes()|.
//
// In addition, marker makes LI non self-collapsing. If the BFC block-offset of
// LI isn't resolved after layout marker, we'll resolve it. See
// |BlockLayoutAlgorithm::PositionOrPropagateListMarker()| and
// |BlockLayoutAlgorithm::PositionListMarkerWithoutLineBoxes()| for details.
class CORE_EXPORT UnpositionedListMarker final { … };

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_LIST_UNPOSITIONED_LIST_MARKER_H_