Remove NGCaretNavigator

This is a follow-up of changing left/right caret movements from visual
to logical. As NGCaretNavigator is designed for visual caret movements,
it no longer serves any purpose here and hence is also removed.

Bug: 958831
Change-Id: I2b18cf81ca9a997851e05617927c608b4831abbe
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1602975Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#658277}

third_party/blink/renderer/core/BUILD.gn

@@ -1982,7 +1982,6 @@ jumbo_source_set("unit_tests") {
     "layout/ng/exclusions/ng_exclusion_space_test.cc",
     "layout/ng/geometry/ng_box_strut_test.cc",
     "layout/ng/inline/ng_baseline_test.cc",
-    "layout/ng/inline/ng_caret_navigator_test.cc",
     "layout/ng/inline/ng_caret_position_test.cc",
     "layout/ng/inline/ng_inline_fragment_traversal_test.cc",
     "layout/ng/inline/ng_inline_items_builder_test.cc",

third_party/blink/renderer/core/editing/visible_position.cc

@@ -31,14 +31,13 @@
 #include "third_party/blink/renderer/core/dom/document.h"
 #include "third_party/blink/renderer/core/dom/text.h"
 #include "third_party/blink/renderer/core/editing/editing_utilities.h"
+#include "third_party/blink/renderer/core/editing/local_caret_rect.h"
 #include "third_party/blink/renderer/core/editing/ng_flat_tree_shorthands.h"
 #include "third_party/blink/renderer/core/editing/text_affinity.h"
 #include "third_party/blink/renderer/core/editing/visible_units.h"
 #include "third_party/blink/renderer/core/html/html_element.h"
 #include "third_party/blink/renderer/core/html_names.h"
 #include "third_party/blink/renderer/core/layout/layout_object.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_inline_node.h"
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_offset_mapping.h"
 #include "third_party/blink/renderer/platform/bindings/exception_state.h"
 #include "third_party/blink/renderer/platform/geometry/float_quad.h"
@@ -100,36 +99,10 @@ VisiblePositionTemplate<Strategy> VisiblePositionTemplate<Strategy>::Create(
     const PositionWithAffinityTemplate<Strategy> upstream_position(
         deep_position, TextAffinity::kUpstream);
 
-    if (!InSameLine(downstream_position, upstream_position))
+    if (AbsoluteCaretBoundsOf(downstream_position) !=
+        AbsoluteCaretBoundsOf(upstream_position)) {
       return VisiblePositionTemplate<Strategy>(upstream_position);
-
-    if (!NGOffsetMapping::AcceptsPosition(ToPositionInDOMTree(deep_position))) {
-      // editing/selection/mixed-editability-10.html reaches here.
-      // We can't check bidi in such case. Use downstream as the default.
-      // TODO(xiaochengh): Investigate why we reach here and how to work around.
-      return VisiblePositionTemplate<Strategy>(downstream_position);
     }
-
-    // Check if the position is at bidi boundary.
-    const LayoutObject* layout_object =
-        deep_position.AnchorNode()->GetLayoutObject();
-    DCHECK(layout_object) << position_with_affinity;
-    if (!layout_object->IsInline())
-      return VisiblePositionTemplate<Strategy>(downstream_position);
-    LayoutBlockFlow* const context =
-        NGOffsetMapping::GetInlineFormattingContextOf(*layout_object);
-    DCHECK(context);
-    DCHECK(context->IsLayoutNGMixin());
-
-    const NGOffsetMapping* mapping = NGInlineNode::GetOffsetMapping(context);
-    DCHECK(mapping);
-
-    const base::Optional<unsigned> offset =
-        mapping->GetTextContentOffset(ToPositionInDOMTree(deep_position));
-    DCHECK(offset.has_value());
-
-    if (NGCaretNavigator(*context).OffsetIsBidiBoundary(offset.value()))
-      return VisiblePositionTemplate<Strategy>(upstream_position);
     return VisiblePositionTemplate<Strategy>(downstream_position);
   }
 

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

@@ -329,8 +329,6 @@ blink_core_sources("layout") {
     "ng/inline/ng_baseline.h",
     "ng/inline/ng_bidi_paragraph.cc",
     "ng/inline/ng_bidi_paragraph.h",
-    "ng/inline/ng_caret_navigator.cc",
-    "ng/inline/ng_caret_navigator.h",
     "ng/inline/ng_caret_position.cc",
     "ng/inline/ng_caret_position.h",
     "ng/inline/ng_caret_rect.cc",

third_party/blink/renderer/core/layout/ng/inline/README.md

@@ -309,11 +309,6 @@ In a bird's‐eye view, it consists of two parts:
 content of an inline formatting context (computed in [pre-layout]) and DOM
 positions in the context. See [design doc](https://goo.gl/CJbxky) for details.
 
-[NGCaretNavigator] provides functions for inspecting bidi levels and visual
-ordering of text content, and supports visual left/right caret movements in the
-text. See [design doc](http://bit.ly/2QVAwGq) for details.
-
-
 [ICU BiDi]: http://userguide.icu-project.org/transforms/bidi
 [UAX#9 Unicode Bidirectional Algorithm]: http://unicode.org/reports/tr9/
 [UAX#9 Resolving Embedding Levels]: http://www.unicode.org/reports/tr9/#Resolving_Embedding_Levels
@@ -322,7 +317,6 @@ text. See [design doc](http://bit.ly/2QVAwGq) for details.
 [FontBaseline]: ../../../platform/fonts/FontBaseline.h
 [NGBaselineAlgorithmType]: ng_baseline.h
 [NGBaselineRequest]: ng_baseline.h
-[NGCaretNavigator]: ng_caret_navigator.h
 [NGBidiParagraph]: ng_bidi_paragraph.h
 [NGBlockNode]: ../ng_block_node.h
 [NGBoxFragment]: ../ng_box_fragment.h

third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.cc

-// Copyright 2018 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/inline/ng_caret_navigator.h"
-
-#include "third_party/blink/renderer/core/layout/layout_text_fragment.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_bidi_paragraph.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_inline_break_token.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_inline_node.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_physical_line_box_fragment.h"
-#include "third_party/blink/renderer/core/layout/ng/ng_physical_box_fragment.h"
-
-namespace blink {
-
-std::ostream& operator<<(std::ostream& out,
-                         const NGCaretNavigator::Position& position) {
-  return out << position.index << "/"
-             << (position.IsBeforeCharacter() ? "BeforeCharacter"
-                                              : "AfterCharacter");
-}
-
-NGCaretNavigator::~NGCaretNavigator() = default;
-
-NGCaretNavigator::NGCaretNavigator(const LayoutBlockFlow& context)
-    : context_(context),
-      disallow_transition_(context.GetDocument().Lifecycle()) {
-  DCHECK(RuntimeEnabledFeatures::BidiCaretAffinityEnabled());
-  DCHECK(context.IsLayoutNGMixin());
-  DCHECK(context.ChildrenInline());
-  DCHECK(context.GetNGInlineNodeData());
-  DCHECK(!context.GetDocument().NeedsLayoutTreeUpdate());
-}
-
-const NGInlineNodeData& NGCaretNavigator::GetData() const {
-  return *context_.GetNGInlineNodeData();
-}
-
-const String& NGCaretNavigator::GetText() const {
-  return GetData().text_content;
-}
-
-bool NGCaretNavigator::IsBidiEnabled() const {
-  return GetData().IsBidiEnabled();
-}
-
-UBiDiLevel NGCaretNavigator::BidiLevelAt(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  if (!IsBidiEnabled())
-    return 0;
-  return GetData().FindItemForTextOffset(index).BidiLevel();
-}
-
-TextDirection NGCaretNavigator::TextDirectionAt(unsigned index) const {
-  UBiDiLevel level = BidiLevelAt(index);
-  return DirectionFromLevel(level);
-}
-
-bool NGCaretNavigator::OffsetIsBidiBoundary(unsigned offset) const {
-  DCHECK_LE(offset, GetText().length());
-  if (!IsBidiEnabled())
-    return false;
-  if (!offset || offset == GetText().length())
-    return false;
-  return BidiLevelAt(offset - 1) != BidiLevelAt(offset);
-}
-
-NGCaretNavigator::Position
-NGCaretNavigator::CaretPositionFromTextContentOffsetAndAffinity(
-    unsigned offset,
-    TextAffinity affinity) const {
-  DCHECK_LE(offset, GetText().length());
-  // Callers sometimes pass in (0, upstream) or (length, downstream), which
-  // originate from legacy callers. Make sure they are fixed up.
-  // TODO(xiaochengh): Catch and eliminate such callers.
-  if (affinity == TextAffinity::kUpstream) {
-    if (offset)
-      return {offset - 1, PositionAnchorType::kAfter};
-    return {0, PositionAnchorType::kBefore};
-  }
-
-  if (offset < GetText().length())
-    return {offset, PositionAnchorType::kBefore};
-  return {GetText().length() - 1, PositionAnchorType::kAfter};
-}
-
-// static
-NGCaretNavigator::MoveDirection NGCaretNavigator::OppositeDirectionOf(
-    MoveDirection direction) {
-  if (direction == MoveDirection::kTowardsLeft)
-    return MoveDirection::kTowardsRight;
-  return MoveDirection::kTowardsLeft;
-}
-
-// static
-bool NGCaretNavigator::TowardsSameDirection(MoveDirection move_direction,
-                                            TextDirection text_direction) {
-  if (IsLtr(text_direction))
-    return move_direction == MoveDirection::kTowardsRight;
-  return move_direction == MoveDirection::kTowardsLeft;
-}
-
-NGCaretNavigator::Line NGCaretNavigator::ContainingLineOf(
-    unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  // TODO(xiaochengh): Make it work for multi-col
-  DCHECK(context_.CurrentFragment());
-  unsigned last_line_end = 0;
-  for (const auto child : context_.CurrentFragment()->Children()) {
-    if (!child->IsLineBox())
-      continue;
-    const auto* line = To<NGPhysicalLineBoxFragment>(child.get());
-    const auto* token = To<NGInlineBreakToken>(line->BreakToken());
-    const unsigned line_end =
-        token->IsFinished() ? GetText().length() : token->TextOffset();
-    if (line_end > index)
-      return {last_line_end, line_end, line->BaseDirection()};
-    last_line_end = line_end;
-  }
-  NOTREACHED();
-  return {};
-}
-
-bool NGCaretNavigator::IsValidCaretPosition(const Position& position) const {
-  unsigned index = position.index;
-  if (position.IsAfterCharacter() && IsLineBreak(index))
-    return false;
-  if (IsCollapsedSpaceByLineWrap(index))
-    return false;
-  if (IsIgnoredInCaretMovement(index))
-    return false;
-  return true;
-}
-
-bool NGCaretNavigator::IsCollapsibleWhitespace(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  if (GetText()[index] != kSpaceCharacter)
-    return false;
-  const NGInlineItem& item = GetData().FindItemForTextOffset(index);
-  return item.Style()->CollapseWhiteSpace();
-}
-
-bool NGCaretNavigator::IsLineBreak(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  return GetText()[index] == kNewlineCharacter;
-}
-
-bool NGCaretNavigator::IsCollapsedSpaceByLineWrap(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  if (!IsCollapsibleWhitespace(index))
-    return false;
-  return index + 1 == ContainingLineOf(index).end_offset;
-}
-
-bool NGCaretNavigator::IsIgnoredInCaretMovement(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  const NGInlineItem& item = GetData().FindItemForTextOffset(index);
-
-  // Caret navigation works on text, atomic inlines and non-ZWS controls only.
-  switch (item.Type()) {
-    case NGInlineItem::kText:
-    case NGInlineItem::kAtomicInline:
-      break;
-    case NGInlineItem::kControl:
-      if (GetText()[index] == kZeroWidthSpaceCharacter)
-        return true;
-      break;
-    default:
-      return true;
-  }
-
-  // Ignore CSS generate contents.
-  // TODO(xiaochengh): This might be general enough to be merged into
-  // |NGInlineItem| as a member function.
-  DCHECK(item.GetLayoutObject());
-  const LayoutObject* object = item.GetLayoutObject();
-  if (const auto* text_fragment = ToLayoutTextFragmentOrNull(object)) {
-    // ::first-letter |LayoutTextFragment| returns null for |GetNode()|. Check
-    // |AssociatedTextNode()| to see if it's created by a text node.
-    if (!text_fragment->AssociatedTextNode())
-      return true;
-  } else {
-    if (!object->NonPseudoNode())
-      return true;
-  }
-
-  // Ignore collapsed whitespaces that not visually at line end due to bidi.
-  // Caret movement should move over them as if they don't exist to match the
-  // existing behavior.
-  return IsCollapsedSpaceByLineWrap(index) &&
-         index != VisualLastCharacterOf(ContainingLineOf(index));
-}
-
-bool NGCaretNavigator::IsEnterableChildContext(unsigned index) const {
-  DCHECK_LT(index, GetText().length());
-  if (GetText()[index] != kObjectReplacementCharacter)
-    return false;
-
-  const NGInlineItem& item = GetData().FindItemForTextOffset(index);
-  if (item.Type() != NGInlineItem::kAtomicInline)
-    return false;
-  DCHECK(item.GetLayoutObject());
-  const LayoutObject* object = item.GetLayoutObject();
-  if (!object->IsLayoutBlockFlow())
-    return false;
-  if (!object->NonPseudoNode() || !object->GetNode()->IsElementNode())
-    return false;
-  const Element* node = ToElement(object->GetNode());
-  return !node->GetShadowRoot() || !node->GetShadowRoot()->IsUserAgent();
-}
-
-NGCaretNavigator::Position NGCaretNavigator::LeftEdgeOf(unsigned index) const {
-  return EdgeOfInternal(index, MoveDirection::kTowardsLeft);
-}
-
-NGCaretNavigator::Position NGCaretNavigator::RightEdgeOf(unsigned index) const {
-  return EdgeOfInternal(index, MoveDirection::kTowardsRight);
-}
-
-NGCaretNavigator::Position NGCaretNavigator::EdgeOfInternal(
-    unsigned index,
-    MoveDirection edge_direction) const {
-  DCHECK_LT(index, GetText().length());
-  const TextDirection character_direction = TextDirectionAt(index);
-  return {index, TowardsSameDirection(edge_direction, character_direction)
-                     ? PositionAnchorType::kAfter
-                     : PositionAnchorType::kBefore};
-}
-
-NGCaretNavigator::VisualCharacterMovementResult
-NGCaretNavigator::LeftCharacterOf(unsigned index) const {
-  return MoveCharacterInternal(index, MoveDirection::kTowardsLeft);
-}
-
-NGCaretNavigator::VisualCharacterMovementResult
-NGCaretNavigator::RightCharacterOf(unsigned index) const {
-  return MoveCharacterInternal(index, MoveDirection::kTowardsRight);
-}
-
-Vector<int32_t, 32> NGCaretNavigator::CharacterIndicesInVisualOrder(
-    const Line& line) const {
-  DCHECK(IsBidiEnabled());
-
-  Vector<UBiDiLevel, 32> levels;
-  levels.ReserveCapacity(line.end_offset - line.start_offset);
-  for (unsigned i = line.start_offset; i < line.end_offset; ++i)
-    levels.push_back(BidiLevelAt(i));
-
-  Vector<int32_t, 32> indices(levels.size());
-  NGBidiParagraph::IndicesInVisualOrder(levels, &indices);
-
-  for (auto& index : indices)
-    index += line.start_offset;
-  return indices;
-}
-
-unsigned NGCaretNavigator::VisualMostForwardCharacterOf(
-    const Line& line,
-    MoveDirection direction) const {
-  if (!IsBidiEnabled()) {
-    if (direction == MoveDirection::kTowardsLeft)
-      return line.start_offset;
-    return line.end_offset - 1;
-  }
-
-  const auto indices_in_visual_order = CharacterIndicesInVisualOrder(line);
-  if (direction == MoveDirection::kTowardsLeft)
-    return indices_in_visual_order.front();
-  return indices_in_visual_order.back();
-}
-
-unsigned NGCaretNavigator::VisualFirstCharacterOf(const Line& line) const {
-  return VisualMostForwardCharacterOf(line, IsLtr(line.base_direction)
-                                                ? MoveDirection::kTowardsLeft
-                                                : MoveDirection::kTowardsRight);
-}
-
-unsigned NGCaretNavigator::VisualLastCharacterOf(const Line& line) const {
-  return VisualMostForwardCharacterOf(line, IsLtr(line.base_direction)
-                                                ? MoveDirection::kTowardsRight
-                                                : MoveDirection::kTowardsLeft);
-}
-
-NGCaretNavigator::VisualCharacterMovementResult
-NGCaretNavigator::MoveCharacterInternal(unsigned index,
-                                        MoveDirection move_direction) const {
-  const Line line = ContainingLineOf(index);
-
-  if (index == VisualMostForwardCharacterOf(line, move_direction)) {
-    if (TowardsSameDirection(move_direction, line.base_direction)) {
-      if (line.end_offset == GetText().length())
-        return {VisualMovementResultType::kAfterContext, base::nullopt};
-      const Line next_line = ContainingLineOf(line.end_offset);
-      return {VisualMovementResultType::kWithinContext,
-              VisualFirstCharacterOf(next_line)};
-    }
-
-    if (!line.start_offset)
-      return {VisualMovementResultType::kBeforeContext, base::nullopt};
-    const Line last_line = ContainingLineOf(line.start_offset - 1);
-    return {VisualMovementResultType::kWithinContext,
-            VisualLastCharacterOf(last_line)};
-  }
-
-  if (!IsBidiEnabled()) {
-    if (move_direction == MoveDirection::kTowardsLeft)
-      return {VisualMovementResultType::kWithinContext, index - 1};
-    return {VisualMovementResultType::kWithinContext, index + 1};
-  }
-
-  Vector<int32_t, 32> indices_in_visual_order =
-      CharacterIndicesInVisualOrder(line);
-  const int32_t* visual_location = std::find(
-      indices_in_visual_order.begin(), indices_in_visual_order.end(), index);
-  DCHECK_NE(visual_location, indices_in_visual_order.end());
-  if (move_direction == MoveDirection::kTowardsLeft) {
-    DCHECK_NE(visual_location, indices_in_visual_order.begin());
-    return {VisualMovementResultType::kWithinContext,
-            *std::prev(visual_location)};
-  }
-  DCHECK_NE(std::next(visual_location), indices_in_visual_order.end());
-  return {VisualMovementResultType::kWithinContext,
-          *std::next(visual_location)};
-}
-
-NGCaretNavigator::VisualCaretMovementResult NGCaretNavigator::LeftPositionOf(
-    const Position& caret_position) const {
-  return MoveCaretInternal(caret_position, MoveDirection::kTowardsLeft);
-}
-
-NGCaretNavigator::VisualCaretMovementResult NGCaretNavigator::RightPositionOf(
-    const Position& caret_position) const {
-  return MoveCaretInternal(caret_position, MoveDirection::kTowardsRight);
-}
-
-NGCaretNavigator::UnvalidatedVisualCaretMovementResult
-NGCaretNavigator::MoveCaretWithoutValidation(
-    const Position& caret_position,
-    MoveDirection move_direction) const {
-  const unsigned index = caret_position.index;
-  const MoveDirection opposite_direction = OppositeDirectionOf(move_direction);
-  if (caret_position == EdgeOfInternal(index, opposite_direction)) {
-    // TODO(xiaochengh): Consider grapheme cluster
-    return {VisualMovementResultType::kWithinContext,
-            EdgeOfInternal(index, move_direction),
-            !IsIgnoredInCaretMovement(index)};
-  }
-
-  VisualCharacterMovementResult forward_character =
-      MoveCharacterInternal(index, move_direction);
-  if (!forward_character.IsWithinContext())
-    return {forward_character.type};
-
-  DCHECK(forward_character.index.has_value());
-  const Position forward_caret =
-      EdgeOfInternal(*forward_character.index, opposite_direction);
-  return {VisualMovementResultType::kWithinContext, forward_caret};
-}
-
-NGCaretNavigator::VisualCaretMovementResult NGCaretNavigator::MoveCaretInternal(
-    const Position& caret_position,
-    MoveDirection move_direction) const {
-  bool has_passed_character = false;
-  base::Optional<Position> last_position;
-  for (Position runner = caret_position;
-       !has_passed_character || !IsValidCaretPosition(runner);) {
-    const UnvalidatedVisualCaretMovementResult next =
-        MoveCaretWithoutValidation(runner, move_direction);
-    if (next.type != VisualMovementResultType::kWithinContext)
-      return {next.type, base::nullopt};
-
-    if (next.has_passed_character) {
-      has_passed_character = true;
-
-      const unsigned last_passed_character = next.position->index;
-      if (IsEnterableChildContext(last_passed_character))
-        return {VisualMovementResultType::kEnteredChildContext, runner};
-    }
-
-    runner = *next.position;
-    last_position = runner;
-
-    // TODO(xiaochengh): Handle the case where we reach a different line with a
-    // different base direction, which occurs with 'unicode-bidi: plain-text'.
-  }
-  DCHECK(last_position.has_value());
-  return {VisualMovementResultType::kWithinContext, *last_position};
-}
-
-NGCaretNavigator::Position NGCaretNavigator::LeftmostPositionInFirstLine()
-    const {
-  Line first_line = ContainingLineOf(0);
-  unsigned leftmost_character =
-      VisualMostForwardCharacterOf(first_line, MoveDirection::kTowardsLeft);
-  // TODO(xiaochengh): Handle if the caret position is invalid.
-  return LeftEdgeOf(leftmost_character);
-}
-
-NGCaretNavigator::Position NGCaretNavigator::RightmostPositionInFirstLine()
-    const {
-  Line first_line = ContainingLineOf(0);
-  unsigned rightmost_character =
-      VisualMostForwardCharacterOf(first_line, MoveDirection::kTowardsRight);
-  // TODO(xiaochengh): Handle if the caret position is invalid.
-  return RightEdgeOf(rightmost_character);
-}
-
-NGCaretNavigator::Position NGCaretNavigator::LeftmostPositionInLastLine()
-    const {
-  Line last_line = ContainingLineOf(GetText().length() - 1);
-  unsigned leftmost_character =
-      VisualMostForwardCharacterOf(last_line, MoveDirection::kTowardsLeft);
-  // TODO(xiaochengh): Handle if the caret position is invalid.
-  return LeftEdgeOf(leftmost_character);
-}
-
-NGCaretNavigator::Position NGCaretNavigator::RightmostPositionInLastLine()
-    const {
-  Line last_line = ContainingLineOf(GetText().length() - 1);
-  unsigned rightmost_character =
-      VisualMostForwardCharacterOf(last_line, MoveDirection::kTowardsRight);
-  // TODO(xiaochengh): Handle if the caret position is invalid.
-  return RightEdgeOf(rightmost_character);
-}
-
-}  // namespace blink

third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.h

-// Copyright 2018 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_INLINE_NG_CARET_NAVIGATOR_H_
-#define THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_NG_INLINE_NG_CARET_NAVIGATOR_H_
-
-#include "base/optional.h"
-#include "third_party/blink/renderer/core/core_export.h"
-#include "third_party/blink/renderer/core/dom/document_lifecycle.h"
-#include "third_party/blink/renderer/core/editing/text_affinity.h"
-#include "third_party/blink/renderer/platform/text/text_direction.h"
-#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
-#include "third_party/blink/renderer/platform/wtf/vector.h"
-
-#include <unicode/ubidi.h>
-
-namespace blink {
-
-class LayoutBlockFlow;
-struct NGInlineNodeData;
-
-// Hosts the |text_content| of an inline formatting context and provides
-// bidi-related utilities, including checking bidi levels, computing visual
-// left/right characters and visual left/right caret movements.
-// Design doc: http://bit.ly/2QVAwGq
-class CORE_EXPORT NGCaretNavigator {
-  STACK_ALLOCATED();
-
- public:
-  explicit NGCaretNavigator(const LayoutBlockFlow&);
-  ~NGCaretNavigator();
-
-  const String& GetText() const;
-  bool IsBidiEnabled() const;
-
-  // Abstraction of a caret position in |text_|.
-  enum class PositionAnchorType { kBefore, kAfter };
-  struct Position {
-    // |index| is character index the |text_| string.
-    unsigned index;
-    PositionAnchorType type;
-
-    bool IsBeforeCharacter() const {
-      return type == PositionAnchorType::kBefore;
-    }
-
-    bool IsAfterCharacter() const { return type == PositionAnchorType::kAfter; }
-
-    bool operator==(const Position& other) const {
-      return index == other.index && type == other.type;
-    }
-  };
-
-  // Returns the bidi level or resolved direction of the character at the given
-  // logical |index|.
-  UBiDiLevel BidiLevelAt(unsigned index) const;
-  TextDirection TextDirectionAt(unsigned index) const;
-
-  // Returns true if the characters at indexes |offset - 1| and |offset| both
-  // exist and are at different bidi levels.
-  bool OffsetIsBidiBoundary(unsigned offset) const;
-
-  // Converts an (offset, affinity) pair into a |Position| type of this class.
-  // Intiontionally long name to indicate the hackiness for handling legacy
-  // callers.
-  Position CaretPositionFromTextContentOffsetAndAffinity(
-      unsigned offset,
-      TextAffinity affinity) const;
-
-  // Returns the visual left/right edge caret position of the character at the
-  // given logical |index|.
-  Position LeftEdgeOf(unsigned index) const;
-  Position RightEdgeOf(unsigned index) const;
-
-  // Left/right visual movements
-  // TODO(xiaochengh): Handle the following
-  // - Grapheme clusters
-
-  enum class VisualMovementResultType {
-    kWithinContext,
-    kBeforeContext,
-    kAfterContext,
-    kEnteredChildContext
-  };
-
-  // Given the character at the logical |index|, returns the logical index of
-  // the character at its left/right side.
-  struct VisualCharacterMovementResult {
-    bool IsWithinContext() const {
-      return type == VisualMovementResultType::kWithinContext;
-    }
-    bool IsBeforeContext() const {
-      return type == VisualMovementResultType::kBeforeContext;
-    }
-    bool IsAfterContext() const {
-      return type == VisualMovementResultType::kAfterContext;
-    }
-
-    VisualMovementResultType type;
-    base::Optional<unsigned> index;
-  };
-  VisualCharacterMovementResult LeftCharacterOf(unsigned index) const;
-  VisualCharacterMovementResult RightCharacterOf(unsigned index) const;
-
-  // Given a caret position, moves it left/right by one grapheme cluster and
-  // returns the result.
-  // Note: If we end up entering an inline block, the result |Position| is
-  // either before or after the inline block, depending on from which side the
-  // inline block is entered. For example:
-  // RightPositionOf(abc|<inline-block>def</inline-block>ghi)
-  // -> {inline-block, PositionAnchorType::kBefore}
-  // LeftPositionOf(abc<inline-block>def</inline-block>|ghi)
-  // -> {inline-block, PositionAnchorType::kAfter}
-  struct VisualCaretMovementResult {
-    bool IsWithinContext() const {
-      return type == VisualMovementResultType::kWithinContext;
-    }
-    bool IsBeforeContext() const {
-      return type == VisualMovementResultType::kBeforeContext;
-    }
-    bool IsAfterContext() const {
-      return type == VisualMovementResultType::kAfterContext;
-    }
-    bool HasEnteredChildContext() const {
-      return type == VisualMovementResultType::kEnteredChildContext;
-    }
-
-    VisualMovementResultType type;
-    base::Optional<Position> position;
-  };
-  VisualCaretMovementResult LeftPositionOf(const Position&) const;
-  VisualCaretMovementResult RightPositionOf(const Position&) const;
-
-  // TODO(xiaochengh): Specify and implement the behavior in edge cases, e.g.,
-  // when the leftmost character of the first line is CSS-generated.
-  Position LeftmostPositionInFirstLine() const;
-  Position RightmostPositionInFirstLine() const;
-  Position LeftmostPositionInLastLine() const;
-  Position RightmostPositionInLastLine() const;
-
- private:
-  // A caret position is invalid if it is:
-  // - kAfter to a line break character.
-  // - Anchored to a collapsible space that's removed by line wrap.
-  // - Anchored to a character that's ignored in caret movement.
-  bool IsValidCaretPosition(const Position&) const;
-  bool IsLineBreak(unsigned index) const;
-  bool IsCollapsibleWhitespace(unsigned index) const;
-  bool IsCollapsedSpaceByLineWrap(unsigned index) const;
-  bool IsIgnoredInCaretMovement(unsigned index) const;
-
-  // Returns true if the character at |index| represents a child block
-  // formatting context that can be entered by caret navigation. Such contexts
-  // must be atomic inlines (inline block, inline table, ...) and must not host
-  // user agent shadow tree (which excludes, e.g., <input> and image alt text).
-  bool IsEnterableChildContext(unsigned index) const;
-
-  enum class MoveDirection { kTowardsLeft, kTowardsRight };
-  static MoveDirection OppositeDirectionOf(MoveDirection);
-  static bool TowardsSameDirection(MoveDirection, TextDirection);
-
-  // ------ Line-related functions ------
-
-  // A line contains a consecutive substring of |GetText()|. The lines should
-  // not overlap, and should together cover the entire |GetText()|.
-  struct Line {
-    unsigned start_offset;
-    unsigned end_offset;
-    TextDirection base_direction;
-  };
-  Line ContainingLineOf(unsigned index) const;
-  Vector<int32_t, 32> CharacterIndicesInVisualOrder(const Line&) const;
-  unsigned VisualMostForwardCharacterOf(const Line&,
-                                        MoveDirection direction) const;
-  unsigned VisualLastCharacterOf(const Line&) const;
-  unsigned VisualFirstCharacterOf(const Line&) const;
-
-  // ------ Implementation of public visual movement functions ------
-
-  Position EdgeOfInternal(unsigned index, MoveDirection) const;
-  VisualCharacterMovementResult MoveCharacterInternal(unsigned index,
-                                                      MoveDirection) const;
-  VisualCaretMovementResult MoveCaretInternal(const Position&,
-                                              MoveDirection) const;
-
-  // Performs a "minimal" caret movement to the left/right without validating
-  // the result. The result might be invalid due to, e.g., anchored to an
-  // unallowed character, being visually the same as the input, etc. It's a
-  // subroutine of |MoveCaretInternal|, who keeps calling it until both of the
-  // folliwng are satisfied:
-  // - We've reached a valid caret position.
-  // - During the process, the caret has moved passing a character on which
-  // |IsIgnoredInCaretMovement| is false (indicated by |has_passed_character|).
-  struct UnvalidatedVisualCaretMovementResult {
-    VisualMovementResultType type;
-    base::Optional<Position> position;
-    bool has_passed_character = false;
-  };
-  UnvalidatedVisualCaretMovementResult MoveCaretWithoutValidation(
-      const Position&,
-      MoveDirection) const;
-
-  const NGInlineNodeData& GetData() const;
-
-  const LayoutBlockFlow& context_;
-  DocumentLifecycle::DisallowTransitionScope disallow_transition_;
-};
-
-CORE_EXPORT std::ostream& operator<<(std::ostream&,
-                                     const NGCaretNavigator::Position&);
-
-}  // namespace blink
-
-#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_LAYOUT_NG_INLINE_NG_CARET_NAVIGATOR_H_

third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator_test.cc

-// Copyright 2018 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/inline/ng_caret_navigator.h"
-
-#include "third_party/blink/renderer/core/layout/ng/layout_ng_block_flow.h"
-#include "third_party/blink/renderer/core/layout/ng/ng_layout_test.h"
-#include "third_party/blink/renderer/core/layout/ng/ng_physical_box_fragment.h"
-
-namespace blink {
-
-class NGCaretNavigatorTest : public RenderingTest,
-                             private ScopedBidiCaretAffinityForTest {
- public:
-  NGCaretNavigatorTest() : ScopedBidiCaretAffinityForTest(true) {}
-
-  void SetupHtml(const char* id, String html) {
-    SetBodyInnerHTML(html);
-
-    block_flow_ = To<LayoutBlockFlow>(GetLayoutObjectByElementId(id));
-    DCHECK(block_flow_);
-    DCHECK(block_flow_->IsLayoutNGMixin());
-    DCHECK(block_flow_->ChildrenInline());
-  }
-
-  UBiDiLevel BidiLevelAt(unsigned index) const {
-    return NGCaretNavigator(*block_flow_).BidiLevelAt(index);
-  }
-
-  NGCaretNavigator::VisualCharacterMovementResult LeftCharacterOf(
-      unsigned index) const {
-    return NGCaretNavigator(*block_flow_).LeftCharacterOf(index);
-  }
-
-  NGCaretNavigator::VisualCharacterMovementResult RightCharacterOf(
-      unsigned index) const {
-    return NGCaretNavigator(*block_flow_).RightCharacterOf(index);
-  }
-
-  NGCaretNavigator::Position CaretBefore(unsigned index) const {
-    return {index, NGCaretNavigator::PositionAnchorType::kBefore};
-  }
-
-  NGCaretNavigator::Position CaretAfter(unsigned index) const {
-    return {index, NGCaretNavigator::PositionAnchorType::kAfter};
-  }
-
-  NGCaretNavigator::VisualCaretMovementResult LeftPositionOf(
-      const NGCaretNavigator::Position& position) const {
-    return NGCaretNavigator(*block_flow_).LeftPositionOf(position);
-  }
-
-  NGCaretNavigator::VisualCaretMovementResult RightPositionOf(
-      const NGCaretNavigator::Position& position) const {
-    return NGCaretNavigator(*block_flow_).RightPositionOf(position);
-  }
-
- protected:
-  const LayoutBlockFlow* block_flow_;
-};
-
-TEST_F(NGCaretNavigatorTest, BidiLevelAtBasic) {
-  SetupHtml("container",
-            "<div id=container>abc&#x05D0;&#x05D1;&#x05D2;123</div>");
-
-  EXPECT_EQ(0u, BidiLevelAt(0));
-  EXPECT_EQ(0u, BidiLevelAt(1));
-  EXPECT_EQ(0u, BidiLevelAt(2));
-  EXPECT_EQ(1u, BidiLevelAt(3));
-  EXPECT_EQ(1u, BidiLevelAt(4));
-  EXPECT_EQ(1u, BidiLevelAt(5));
-  EXPECT_EQ(2u, BidiLevelAt(6));
-  EXPECT_EQ(2u, BidiLevelAt(7));
-  EXPECT_EQ(2u, BidiLevelAt(8));
-}
-
-TEST_F(NGCaretNavigatorTest, LeftCharacterOfBasic) {
-  SetupHtml("container",
-            "<div id=container>abc&#x05D0;&#x05D1;&#x05D2;123</div>");
-
-  EXPECT_TRUE(LeftCharacterOf(0).IsBeforeContext());
-
-  EXPECT_TRUE(LeftCharacterOf(1).IsWithinContext());
-  EXPECT_EQ(0u, *LeftCharacterOf(1).index);
-
-  EXPECT_TRUE(LeftCharacterOf(2).IsWithinContext());
-  EXPECT_EQ(1u, *LeftCharacterOf(2).index);
-
-  EXPECT_TRUE(LeftCharacterOf(3).IsWithinContext());
-  EXPECT_EQ(4u, *LeftCharacterOf(3).index);
-
-  EXPECT_TRUE(LeftCharacterOf(4).IsWithinContext());
-  EXPECT_EQ(5u, *LeftCharacterOf(4).index);
-
-  EXPECT_TRUE(LeftCharacterOf(5).IsWithinContext());
-  EXPECT_EQ(8u, *LeftCharacterOf(5).index);
-
-  EXPECT_TRUE(LeftCharacterOf(6).IsWithinContext());
-  EXPECT_EQ(2u, *LeftCharacterOf(6).index);
-
-  EXPECT_TRUE(LeftCharacterOf(7).IsWithinContext());
-  EXPECT_EQ(6u, *LeftCharacterOf(7).index);
-
-  EXPECT_TRUE(LeftCharacterOf(8).IsWithinContext());
-  EXPECT_EQ(7u, *LeftCharacterOf(8).index);
-}
-
-TEST_F(NGCaretNavigatorTest, RightCharacterOfBasic) {
-  SetupHtml("container",
-            "<div id=container>abc&#x05D0;&#x05D1;&#x05D2;123</div>");
-
-  EXPECT_TRUE(RightCharacterOf(0).IsWithinContext());
-  EXPECT_EQ(1u, *RightCharacterOf(0).index);
-
-  EXPECT_TRUE(RightCharacterOf(1).IsWithinContext());
-  EXPECT_EQ(2u, *RightCharacterOf(1).index);
-
-  EXPECT_TRUE(RightCharacterOf(2).IsWithinContext());
-  EXPECT_EQ(6u, *RightCharacterOf(2).index);
-
-  EXPECT_TRUE(RightCharacterOf(3).IsAfterContext());
-
-  EXPECT_TRUE(RightCharacterOf(4).IsWithinContext());
-  EXPECT_EQ(3u, *RightCharacterOf(4).index);
-
-  EXPECT_TRUE(RightCharacterOf(5).IsWithinContext());
-  EXPECT_EQ(4u, *RightCharacterOf(5).index);
-
-  EXPECT_TRUE(RightCharacterOf(6).IsWithinContext());
-  EXPECT_EQ(7u, *RightCharacterOf(6).index);
-
-  EXPECT_TRUE(RightCharacterOf(7).IsWithinContext());
-  EXPECT_EQ(8u, *RightCharacterOf(7).index);
-
-  EXPECT_TRUE(RightCharacterOf(8).IsWithinContext());
-  EXPECT_EQ(5u, *RightCharacterOf(8).index);
-}
-
-TEST_F(NGCaretNavigatorTest, LeftPositionOfBasic) {
-  SetupHtml("container",
-            "<div id=container>abc&#x05D0;&#x05D1;&#x05D2;123</div>");
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(0)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(0), *LeftPositionOf(CaretAfter(0)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(1)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(0), *LeftPositionOf(CaretBefore(1)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(1)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(1), *LeftPositionOf(CaretAfter(1)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(2)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(1), *LeftPositionOf(CaretBefore(2)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(2), *LeftPositionOf(CaretAfter(2)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(3)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(3), *LeftPositionOf(CaretBefore(3)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(3)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(4), *LeftPositionOf(CaretAfter(3)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(4), *LeftPositionOf(CaretBefore(4)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(4)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(5), *LeftPositionOf(CaretAfter(4)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(5)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(5), *LeftPositionOf(CaretBefore(5)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(8), *LeftPositionOf(CaretAfter(5)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(6)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(2), *LeftPositionOf(CaretBefore(6)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(6)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(6), *LeftPositionOf(CaretAfter(6)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(7)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(6), *LeftPositionOf(CaretBefore(7)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(7)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(7), *LeftPositionOf(CaretAfter(7)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(8)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(7), *LeftPositionOf(CaretBefore(8)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(8)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(8), *LeftPositionOf(CaretAfter(8)).position);
-}
-
-TEST_F(NGCaretNavigatorTest, RightPositionOfBasic) {
-  SetupHtml("container",
-            "<div id=container>abc&#x05D0;&#x05D1;&#x05D2;123</div>");
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(0)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(0), *RightPositionOf(CaretBefore(0)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(0)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(1), *RightPositionOf(CaretAfter(0)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(1)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(1), *RightPositionOf(CaretBefore(1)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(1)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(2), *RightPositionOf(CaretAfter(1)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(2)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(2), *RightPositionOf(CaretBefore(2)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(6), *RightPositionOf(CaretAfter(2)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).IsAfterContext());
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(3)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *RightPositionOf(CaretAfter(3)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *RightPositionOf(CaretBefore(4)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretAfter(4)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretBefore(5)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(5), *RightPositionOf(CaretAfter(5)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(6)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(6), *RightPositionOf(CaretBefore(6)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(6)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(7), *RightPositionOf(CaretAfter(6)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(7)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(7), *RightPositionOf(CaretBefore(7)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(7)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(8), *RightPositionOf(CaretAfter(7)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(8)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(8), *RightPositionOf(CaretBefore(8)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(8)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(5), *RightPositionOf(CaretAfter(8)).position);
-}
-
-// Tests below check caret movement crossing line boundaries
-
-TEST_F(NGCaretNavigatorTest, HardLineBreak) {
-  SetupHtml("container", "<div id=container>abc<br>def</div>");
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretAfter(2)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretBefore(3)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *LeftPositionOf(CaretBefore(4)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(6)).IsAfterContext());
-}
-
-TEST_F(NGCaretNavigatorTest, SoftLineWrapAtSpace) {
-  SetupHtml("container", "<div id=container style=\"width:0\">abc def</div>");
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretAfter(2)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretBefore(3)).position);
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(2), *LeftPositionOf(CaretBefore(4)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(6)).IsAfterContext());
-}
-
-TEST_F(NGCaretNavigatorTest, BidiAndSoftLineWrapAtSpaceLtr) {
-  LoadAhem();
-  SetupHtml("container",
-            "<div id=container style='font: 10px/10px Ahem; width: 100px'>"
-            "before    &#x05D0;&#x05D1;&#x05D2;&#x05D3; "
-            "&#x05D4;&#x05D5;&#x05D6;&#x05D7;&#x05D8;&#x05D9;"
-            "&#x05DA;&#x05DB;&#x05DC;&#x05DD;&#x05DE;&#x05DF;"
-            "&#x05E0;&#x05E1;&#x05E2;&#x05E3;&#x05E4;&#x05E5;"
-            "</div>");
-
-  // Moving left from "|before DCBA" should be before context
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  // Moving right from "before |DCBA" should yield "before D|CBA"
-  EXPECT_TRUE(RightPositionOf(CaretAfter(10)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(10), *RightPositionOf(CaretAfter(10)).position);
-  EXPECT_TRUE(RightPositionOf(CaretAfter(6)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(10), *RightPositionOf(CaretAfter(6)).position);
-
-  // Moving left from "before |DCBA" should yield "before| DCBA"
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(10)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(6), *LeftPositionOf(CaretAfter(10)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(6)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(6), *LeftPositionOf(CaretAfter(6)).position);
-
-  // Moving right from "before DCBA|" should yield "V|UTSRQPONMLKJIHGFE"
-  EXPECT_TRUE(RightPositionOf(CaretBefore(7)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(29), *RightPositionOf(CaretBefore(7)).position);
-
-  // Moving left from "|VUTSRQPONMLKJIHGFE" should yield "before DCB|A"
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(29)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(7), *LeftPositionOf(CaretAfter(29)).position);
-
-  // Moving right from "VUTSRQPONMLKJIHGFE|" should be after context
-  EXPECT_TRUE(RightPositionOf(CaretBefore(12)).IsAfterContext());
-}
-
-TEST_F(NGCaretNavigatorTest, BidiAndSoftLineWrapAtSpaceRtl) {
-  LoadAhem();
-  SetupHtml(
-      "container",
-      "<div dir=rtl id=container style='font: 10px/10px Ahem; width: 120px'>"
-      "&#x05D0;&#x05D1;&#x05D2;&#x05D3;    after encyclopedia"
-      "</div>");
-
-  // Moving right from "after DCBA|" should be before context
-  EXPECT_TRUE(RightPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  // Moving left from "after| DCBA" should yield "afte|r DCBA"
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(9), *LeftPositionOf(CaretAfter(4)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(9)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(9), *LeftPositionOf(CaretAfter(9)).position);
-
-  // Moving right from "after| DCBA" should yield "after |DCBA"
-  EXPECT_TRUE(RightPositionOf(CaretAfter(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretAfter(4)).position);
-  EXPECT_TRUE(RightPositionOf(CaretAfter(9)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *RightPositionOf(CaretAfter(9)).position);
-
-  // Moving left from "|after DCBA" should yield "encyclopedi|a"
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(22), *LeftPositionOf(CaretBefore(5)).position);
-
-  // Moving right from "encyclopedia|" should yield "a|fter DCBA"
-  EXPECT_TRUE(RightPositionOf(CaretAfter(22)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(5), *RightPositionOf(CaretAfter(22)).position);
-
-  // Moving left from "|encyclopedia" should be after context
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(11)).IsAfterContext());
-}
-
-TEST_F(NGCaretNavigatorTest, SoftLineWrapAtHyphen) {
-  SetupHtml("container", "<div id=container style=\"width:0\">abc-def</div>");
-
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(0)).IsBeforeContext());
-
-  // 3 -> 4
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(3), *RightPositionOf(CaretAfter(2)).position);
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(3), *RightPositionOf(CaretBefore(3)).position);
-
-  // 4 -> 5
-  EXPECT_TRUE(RightPositionOf(CaretAfter(3)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(4), *RightPositionOf(CaretAfter(3)).position);
-  EXPECT_TRUE(RightPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(4), *RightPositionOf(CaretBefore(4)).position);
-
-  // 5 -> 4
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *LeftPositionOf(CaretBefore(5)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(4), *LeftPositionOf(CaretAfter(4)).position);
-
-  // 4 -> 3
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *LeftPositionOf(CaretBefore(4)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(3)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *LeftPositionOf(CaretAfter(3)).position);
-
-  EXPECT_TRUE(RightPositionOf(CaretAfter(6)).IsAfterContext());
-}
-
-TEST_F(NGCaretNavigatorTest, MoveOverPseudoElementInBidi) {
-  SetupHtml("container",
-            "<style>.bidi::before,.bidi::after{content:'a\\05D0 b'}</style>"
-            "<div id=container>&#x05D0;&#x05D1; &#x05D2;&#x05D3; "
-            "<span class=bidi>&#x05D4;&#x05D5;</span>"
-            " &#x05D6;&#x05D7; &#x05D8;&#x05D9;</div>");
-
-  // Text: "AB CD aAbEFaAb GH IJ"
-  // Rendered as: "DC BA aAbFEaAb JI HG"
-
-  // Moving right from "BA |" should arrive at "F|E"
-  EXPECT_TRUE(RightPositionOf(CaretAfter(5)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(10), *RightPositionOf(CaretAfter(5)).position);
-
-  // Moving left from "|FE" should arrive at "BA| "
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(10)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(5), *LeftPositionOf(CaretAfter(10)).position);
-
-  // Moving right from "FE|" should arrive at " |JI"
-  EXPECT_TRUE(RightPositionOf(CaretBefore(9)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(14), *RightPositionOf(CaretBefore(9)).position);
-
-  // Moving left from "| JI" should arrive at "F|E"
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(14)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(9), *LeftPositionOf(CaretBefore(14)).position);
-}
-
-TEST_F(NGCaretNavigatorTest, EnterableInlineBlock) {
-  SetupHtml("container",
-            "<div id=container>foo"
-            "<span style='display:inline-block'>bar</span>"
-            "baz</div>");
-
-  // Moving right from "foo|" should enter the span from front.
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).HasEnteredChildContext());
-  EXPECT_EQ(CaretBefore(3), *RightPositionOf(CaretAfter(2)).position);
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).HasEnteredChildContext());
-  EXPECT_EQ(CaretBefore(3), *RightPositionOf(CaretBefore(3)).position);
-
-  // Moving left from "|baz" should enter the span from behind.
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).HasEnteredChildContext());
-  EXPECT_EQ(CaretAfter(3), *LeftPositionOf(CaretBefore(4)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(3)).HasEnteredChildContext());
-  EXPECT_EQ(CaretAfter(3), *LeftPositionOf(CaretAfter(3)).position);
-}
-
-TEST_F(NGCaretNavigatorTest, UnenterableInlineBlock) {
-  SetupHtml("container",
-            "<div id=container>foo"
-            "<input value=bar>"
-            "baz</div>");
-
-  // Moving right from "foo|" should reach "<input>|".
-  EXPECT_TRUE(RightPositionOf(CaretAfter(2)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(3), *RightPositionOf(CaretAfter(2)).position);
-  EXPECT_TRUE(RightPositionOf(CaretBefore(3)).IsWithinContext());
-  EXPECT_EQ(CaretAfter(3), *RightPositionOf(CaretBefore(3)).position);
-
-  // Moving left from "|baz" should reach "|<input>".
-  EXPECT_TRUE(LeftPositionOf(CaretBefore(4)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *LeftPositionOf(CaretBefore(4)).position);
-  EXPECT_TRUE(LeftPositionOf(CaretAfter(3)).IsWithinContext());
-  EXPECT_EQ(CaretBefore(3), *LeftPositionOf(CaretAfter(3)).position);
-}
-
-}  // namespace blink

third_party/blink/renderer/core/layout/ng/inline/ng_offset_mapping.cc

@@ -12,7 +12,6 @@
 #include "third_party/blink/renderer/core/editing/ephemeral_range.h"
 #include "third_party/blink/renderer/core/editing/position.h"
 #include "third_party/blink/renderer/core/layout/layout_text_fragment.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.h"
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_inline_node.h"
 #include "third_party/blink/renderer/core/layout/ng/ng_block_node.h"
 #include "third_party/blink/renderer/platform/text/character.h"
@@ -509,16 +508,6 @@ Position NGOffsetMapping::GetLastPosition(unsigned offset) const {
   return CreatePositionForOffsetMapping(node, dom_offset);
 }
 
-PositionWithAffinity NGOffsetMapping::GetPositionWithAffinity(
-    const NGCaretNavigator::Position& position) const {
-  if (position.IsBeforeCharacter()) {
-    return PositionWithAffinity(GetLastPosition(position.index),
-                                TextAffinity::kDownstream);
-  }
-  return PositionWithAffinity(GetFirstPosition(position.index + 1),
-                              TextAffinity::kUpstream);
-}
-
 bool NGOffsetMapping::HasBidiControlCharactersOnly(unsigned start,
                                                    unsigned end) const {
   DCHECK_LE(start, end);

third_party/blink/renderer/core/layout/ng/inline/ng_offset_mapping.h

@@ -9,7 +9,6 @@
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/dom/node.h"
 #include "third_party/blink/renderer/core/editing/forward.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.h"
 #include "third_party/blink/renderer/platform/heap/handle.h"
 #include "third_party/blink/renderer/platform/heap/persistent.h"
 #include "third_party/blink/renderer/platform/wtf/allocator.h"
@@ -219,13 +218,6 @@ class CORE_EXPORT NGOffsetMapping {
   Position GetFirstPosition(unsigned) const;
   Position GetLastPosition(unsigned) const;
 
-  // Converts the given caret position on text content to a PositionWithAffinity
-  // in DOM. If |position| is before a character, the function creates a
-  // downstream position before |GetLastPosition()| of the character; otherwise,
-  // it returns an upstream position after |GetFirstPosition()| of the character
-  PositionWithAffinity GetPositionWithAffinity(
-      const NGCaretNavigator::Position& position) const;
-
   // Returns all NGOffsetMappingUnits whose text content ranges has non-empty
   // (but possibly collapsed) intersection with (start, end). Note that units
   // that only "touch" |start| or |end| are excluded.

third_party/blink/renderer/core/layout/ng/inline/ng_offset_mapping_builder.cc

@@ -7,7 +7,6 @@
 #include <utility>
 #include "third_party/blink/renderer/core/layout/layout_text.h"
 #include "third_party/blink/renderer/core/layout/layout_text_fragment.h"
-#include "third_party/blink/renderer/core/layout/ng/inline/ng_caret_navigator.h"
 #include "third_party/blink/renderer/core/layout/ng/inline/ng_offset_mapping.h"
 
 namespace blink {