[TablesNG] Section layout algorithm

Bug: 958381
Change-Id: I91df6f992533deffb8192d38d167f7bdd20cd6ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2385926
Commit-Queue: Aleks Totic <atotic@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803996}

third_party/blink/renderer/core/layout/BUILD.gn

@@ -568,6 +568,8 @@ blink_core_sources("layout") {
     "ng/table/ng_table_layout_algorithm_utils.h",
     "ng/table/ng_table_row_layout_algorithm.cc",
     "ng/table/ng_table_row_layout_algorithm.h",
+    "ng/table/ng_table_section_layout_algorithm.cc",
+    "ng/table/ng_table_section_layout_algorithm.h",
     "order_iterator.cc",
     "order_iterator.h",
     "overflow_model.h",

third_party/blink/renderer/core/layout/ng/table/ng_table_section_layout_algorithm.cc

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "third_party/blink/renderer/core/layout/ng/table/ng_table_section_layout_algorithm.h"
+
+#include "third_party/blink/renderer/core/layout/ng/ng_block_break_token.h"
+#include "third_party/blink/renderer/core/layout/ng/ng_constraint_space_builder.h"
+#include "third_party/blink/renderer/core/layout/ng/ng_out_of_flow_layout_part.h"
+#include "third_party/blink/renderer/core/layout/ng/ng_physical_box_fragment.h"
+
+namespace blink {
+
+NGTableSectionLayoutAlgorithm::NGTableSectionLayoutAlgorithm(
+    const NGLayoutAlgorithmParams& params)
+    : NGLayoutAlgorithm(params) {
+  container_builder_.SetIsNewFormattingContext(
+      params.space.IsNewFormattingContext());
+}
+
+MinMaxSizesResult NGTableSectionLayoutAlgorithm::ComputeMinMaxSizes(
+    const MinMaxSizesInput&) const {
+  NOTREACHED();  // Table layout does not compute minmax for table row.
+  return MinMaxSizesResult();
+}
+
+// Generated fragment structure:
+// +-----section--------------+
+// |       vspacing           |
+// |  +--------------------+  |
+// |  |      row           |  |
+// |  +--------------------+  |
+// |       vspacing           |
+// |  +--------------------+  |
+// |  |      row           |  |
+// |  +--------------------+  |
+// |       vspacing           |
+// +--------------------------+
+scoped_refptr<const NGLayoutResult> NGTableSectionLayoutAlgorithm::Layout() {
+  const NGTableConstraintSpaceData& table_data = *ConstraintSpace().TableData();
+  wtf_size_t section_index = ConstraintSpace().TableSectionIndex();
+
+  base::Optional<LayoutUnit> section_baseline;
+
+  LogicalOffset offset;
+  bool is_first_row = true;
+  wtf_size_t row_index = table_data.sections[section_index].start_row_index;
+  for (NGBlockNode row = To<NGBlockNode>(Node().FirstChild()); row;
+       row = To<NGBlockNode>(row.NextSibling())) {
+    DCHECK_LT(row_index, table_data.sections[section_index].start_row_index +
+                             table_data.sections[section_index].rowspan);
+    NGConstraintSpaceBuilder row_space_builder(
+        table_data.table_writing_direction.GetWritingMode(),
+        table_data.table_writing_direction.GetWritingMode(),
+        /* is_new_fc */ true);
+    row_space_builder.SetTextDirection(row.Style().Direction());
+    row_space_builder.SetAvailableSize(
+        {container_builder_.InlineSize(), kIndefiniteSize});
+    row_space_builder.SetIsFixedInlineSize(true);
+    row_space_builder.SetPercentageResolutionSize(
+        {container_builder_.InlineSize(), kIndefiniteSize});
+    row_space_builder.SetNeedsBaseline(true);
+    row_space_builder.SetHideTableCellIfEmpty(
+        ConstraintSpace().HideTableCellIfEmpty());
+    row_space_builder.SetTableRowData(&table_data, row_index);
+    NGConstraintSpace row_space = row_space_builder.ToConstraintSpace();
+    scoped_refptr<const NGLayoutResult> row_result = row.Layout(row_space);
+    if (is_first_row) {
+      const NGPhysicalBoxFragment& physical_fragment =
+          To<NGPhysicalBoxFragment>(row_result->PhysicalFragment());
+      DCHECK(physical_fragment.Baseline());
+      section_baseline = physical_fragment.Baseline();
+    } else if (!table_data.rows[row_index].is_collapsed) {
+      offset.block_offset += table_data.table_border_spacing.block_size;
+    }
+    container_builder_.AddResult(*row_result, offset);
+    offset.block_offset += table_data.rows[row_index].block_size;
+    is_first_row = false;
+    row_index++;
+  }
+  container_builder_.SetFragmentBlockSize(offset.block_offset);
+  if (section_baseline)
+    container_builder_.SetBaseline(*section_baseline);
+
+  NGOutOfFlowLayoutPart(Node(), ConstraintSpace(), &container_builder_).Run();
+  return container_builder_.ToBoxFragment();
+}
+
+}  // namespace blink

third_party/blink/renderer/core/layout/ng/table/ng_table_section_layout_algorithm.h

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// 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_NG_TABLE_NG_TABLE_SECTION_LAYOUT_ALGORITHM_H_
+#define THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_NG_TABLE_NG_TABLE_SECTION_LAYOUT_ALGORITHM_H_
+
+#include "third_party/blink/renderer/core/layout/ng/ng_layout_algorithm.h"
+
+#include "third_party/blink/renderer/core/layout/ng/ng_box_fragment_builder.h"
+
+namespace blink {
+
+class NGBlockNode;
+class NGBlockBreakToken;
+
+class CORE_EXPORT NGTableSectionLayoutAlgorithm
+    : public NGLayoutAlgorithm<NGBlockNode,
+                               NGBoxFragmentBuilder,
+                               NGBlockBreakToken> {
+ public:
+  explicit NGTableSectionLayoutAlgorithm(const NGLayoutAlgorithmParams& params);
+
+  scoped_refptr<const NGLayoutResult> Layout() override;
+
+  MinMaxSizesResult ComputeMinMaxSizes(const MinMaxSizesInput&) const override;
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_NG_TABLE_NG_TABLE_SECTION_LAYOUT_ALGORITHM_H_