[Sync] Move //sync to //components/sync.

sync/syncable/parent_child_index.cc

Index: sync/syncable/parent_child_index.cc
diff --git a/sync/syncable/parent_child_index.cc b/sync/syncable/parent_child_index.cc
deleted file mode 100644
index 6d1be8b5c940b439ecf0bfcbfe09af6be9a0a8b5..0000000000000000000000000000000000000000
--- a/sync/syncable/parent_child_index.cc
+++ /dev/null
@@ -1,216 +0,0 @@
-// Copyright (c) 2012 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 "sync/syncable/parent_child_index.h"
-
-#include <memory>
-
-#include "base/stl_util.h"
-#include "sync/syncable/entry_kernel.h"
-#include "sync/syncable/syncable_id.h"
-
-namespace syncer {
-namespace syncable {
-
-bool ChildComparator::operator()(const EntryKernel* a,
-                                 const EntryKernel* b) const {
-  const UniquePosition& a_pos = a->ref(UNIQUE_POSITION);
-  const UniquePosition& b_pos = b->ref(UNIQUE_POSITION);
-
-  if (a_pos.IsValid() && b_pos.IsValid()) {
-    // Position is important to this type.
-    return a_pos.LessThan(b_pos);
-  } else if (a_pos.IsValid() && !b_pos.IsValid()) {
-    // TODO(rlarocque): Remove this case.
-    // An item with valid position as sibling of one with invalid position.
-    // We should not support this, but the tests rely on it.  For now, just
-    // move all invalid position items to the right.
-    return true;
-  } else if (!a_pos.IsValid() && b_pos.IsValid()) {
-    // TODO(rlarocque): Remove this case.
-    // Mirror of the above case.
-    return false;
-  } else {
-    // Position doesn't matter.
-    DCHECK(!a->ref(UNIQUE_POSITION).IsValid());
-    DCHECK(!b->ref(UNIQUE_POSITION).IsValid());
-    // Sort by META_HANDLE to ensure consistent order for testing.
-    return a->ref(META_HANDLE) < b->ref(META_HANDLE);
-  }
-}
-
-ParentChildIndex::ParentChildIndex() {
-  // Pre-allocate these two vectors to the number of model types.
-  model_type_root_ids_.resize(MODEL_TYPE_COUNT);
-  type_root_child_sets_.resize(MODEL_TYPE_COUNT);
-}
-
-ParentChildIndex::~ParentChildIndex() {}
-
-bool ParentChildIndex::ShouldInclude(const EntryKernel* entry) {
-  // This index excludes deleted items and the root item.  The root
-  // item is excluded so that it doesn't show up as a child of itself.
-  return !entry->ref(IS_DEL) && !entry->ref(ID).IsRoot();
-}
-
-bool ParentChildIndex::Insert(EntryKernel* entry) {
-  DCHECK(ShouldInclude(entry));
-
-  OrderedChildSetRef siblings = nullptr;
-  const Id& parent_id = entry->ref(PARENT_ID);
-  ModelType model_type = entry->GetModelType();
-
-  if (ShouldUseParentId(parent_id, model_type)) {
-    // Hierarchical type, lookup child set in the map.
-    DCHECK(!parent_id.IsNull());
-    ParentChildrenMap::iterator it = parent_children_map_.find(parent_id);
-    if (it != parent_children_map_.end()) {
-      siblings = it->second;
-    } else {
-      siblings = OrderedChildSetRef(new OrderedChildSet());
-      parent_children_map_.insert(std::make_pair(parent_id, siblings));
-    }
-  } else {
-    // Non-hierarchical type, return a pre-defined collection by type.
-    siblings = GetOrCreateModelTypeChildSet(model_type);
-  }
-
-  // If this is one of type root folder for a non-hierarchical type, associate
-  // its ID with the model type and the type's pre-defined child set with the
-  // type root ID.
-  // TODO(stanisc): crbug/438313: Just TypeSupportsHierarchy condition should
-  // theoretically be sufficient but in practice many tests don't properly
-  // initialize entries so TypeSupportsHierarchy ends up failing. Consider
-  // tweaking TypeSupportsHierarchy and fixing all related test code.
-  if (parent_id.IsRoot() && entry->ref(IS_DIR) &&
-      syncer::IsRealDataType(model_type) &&
-      !TypeSupportsHierarchy(model_type)) {
-    const Id& type_root_id = entry->ref(ID);
-
-    // If the entry exists in the map it must already have the same
-    // model type specific child set. It's possible another type root exists
-    // in parent_children_map_, but that's okay as the new type root will
-    // point to the same OrderedChildSet. As such, we just blindly store the
-    // new type root ID and associate it to the (possibly existing) child set.
-    model_type_root_ids_[model_type] = type_root_id;
-    parent_children_map_.insert(std::make_pair(
-        type_root_id, GetOrCreateModelTypeChildSet(model_type)));
-  }
-
-  // Finally, insert the entry in the child set.
-  return siblings->insert(entry).second;
-}
-
-// Like the other containers used to help support the syncable::Directory, this
-// one does not own any EntryKernels.  This function removes references to the
-// given EntryKernel but does not delete it.
-void ParentChildIndex::Remove(EntryKernel* e) {
-  OrderedChildSetRef siblings = nullptr;
-  ModelType model_type = e->GetModelType();
-  const Id& parent_id = e->ref(PARENT_ID);
-  bool should_erase = false;
-  ParentChildrenMap::iterator sibling_iterator;
-
-  if (ShouldUseParentId(parent_id, model_type)) {
-    // Hierarchical type, lookup child set in the map.
-    DCHECK(!parent_id.IsNull());
-    sibling_iterator = parent_children_map_.find(parent_id);
-    DCHECK(sibling_iterator != parent_children_map_.end());
-    siblings = sibling_iterator->second;
-    should_erase = true;
-  } else {
-    // Non-hierarchical type, return a pre-defined child set by type.
-    siblings = type_root_child_sets_[model_type];
-  }
-
-  OrderedChildSet::iterator j = siblings->find(e);
-  DCHECK(j != siblings->end());
-
-  // Erase the entry from the child set.
-  siblings->erase(j);
-  // If the set is now empty and isn't shareable with |type_root_child_sets_|,
-  // erase it from the map.
-  if (siblings->empty() && should_erase) {
-    parent_children_map_.erase(sibling_iterator);
-  }
-}
-
-bool ParentChildIndex::Contains(EntryKernel *e) const {
-  const OrderedChildSetRef siblings = GetChildSet(e);
-  return siblings && siblings->count(e) > 0;
-}
-
-const OrderedChildSet* ParentChildIndex::GetChildren(const Id& id) const {
-  DCHECK(!id.IsNull());
-
-  ParentChildrenMap::const_iterator parent = parent_children_map_.find(id);
-  if (parent == parent_children_map_.end()) {
-    return nullptr;
-  }
-
-  OrderedChildSetRef children = parent->second;
-  // The expectation is that the function returns nullptr instead of an empty
-  // child set
-  if (children && children->empty())
-    children = nullptr;
-  return children.get();
-}
-
-const OrderedChildSet* ParentChildIndex::GetChildren(EntryKernel* e) const {
-  return GetChildren(e->ref(ID));
-}
-
-const OrderedChildSet* ParentChildIndex::GetSiblings(EntryKernel* e) const {
-  // This implies the entry is in the index.
-  DCHECK(Contains(e));
-  const OrderedChildSetRef siblings = GetChildSet(e);
-  DCHECK(siblings && !siblings->empty());
-  return siblings.get();
-}
-
-/* static */
-bool ParentChildIndex::ShouldUseParentId(const Id& parent_id,
-                                         ModelType model_type) {
-  // For compatibility with legacy unit tests, in addition to hierarchical
-  // entries, this returns true any entries directly under root and for entries
-  // of UNSPECIFIED model type.
-  return parent_id.IsRoot() || TypeSupportsHierarchy(model_type) ||
-         !syncer::IsRealDataType(model_type);
-}
-
-const OrderedChildSetRef ParentChildIndex::GetChildSet(EntryKernel* e) const {
-  ModelType model_type = e->GetModelType();
-
-  const Id& parent_id = e->ref(PARENT_ID);
-  if (ShouldUseParentId(parent_id, model_type)) {
-    // Hierarchical type, lookup child set in the map.
-    ParentChildrenMap::const_iterator it = parent_children_map_.find(parent_id);
-    if (it == parent_children_map_.end())
-      return nullptr;
-    return it->second;
-  }
-
-  // Non-hierarchical type, return a collection indexed by type.
-  return GetModelTypeChildSet(model_type);
-}
-
-const OrderedChildSetRef ParentChildIndex::GetModelTypeChildSet(
-    ModelType model_type) const {
-  return type_root_child_sets_[model_type];
-}
-
-OrderedChildSetRef ParentChildIndex::GetOrCreateModelTypeChildSet(
-    ModelType model_type) {
-  if (!type_root_child_sets_[model_type])
-    type_root_child_sets_[model_type] =
-        OrderedChildSetRef(new OrderedChildSet());
-  return type_root_child_sets_[model_type];
-}
-
-const Id& ParentChildIndex::GetModelTypeRootId(ModelType model_type) const {
-  return model_type_root_ids_[model_type];
-}
-
-}  // namespace syncable
-}  // namespace syncer