[Sync] Rename ProcessorEntityTracker to ProcessorEntity

This is the first step in the effort of refactoring the
ClientTagBasedModelTypeProcessor.

Bug: 947044
Change-Id: I18acf64ba4edbd8e87cef08754be9460384db078
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1543510
Commit-Queue: Mohamed Amir Yosef <mamir@chromium.org>
Auto-Submit: Mohamed Amir Yosef <mamir@chromium.org>
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#645363}

components/sync/BUILD.gn

@@ -457,8 +457,8 @@ jumbo_static_library("sync") {
     "model_impl/model_type_store_impl.h",
     "model_impl/model_type_store_service_impl.cc",
     "model_impl/model_type_store_service_impl.h",
-    "model_impl/processor_entity_tracker.cc",
-    "model_impl/processor_entity_tracker.h",
+    "model_impl/processor_entity.cc",
+    "model_impl/processor_entity.h",
     "model_impl/proxy_model_type_controller_delegate.cc",
     "model_impl/proxy_model_type_controller_delegate.h",
     "model_impl/sync_metadata_store_change_list.cc",
@@ -930,7 +930,7 @@ source_set("unit_tests") {
     "model_impl/in_memory_metadata_change_list_unittest.cc",
     "model_impl/model_type_store_backend_unittest.cc",
     "model_impl/model_type_store_impl_unittest.cc",
-    "model_impl/processor_entity_tracker_unittest.cc",
+    "model_impl/processor_entity_unittest.cc",
     "model_impl/syncable_service_based_bridge_unittest.cc",
     "protocol/proto_enum_conversions_unittest.cc",
     "protocol/proto_value_conversions_unittest.cc",

components/sync/base/proto_value_ptr.h

@@ -11,7 +11,7 @@
 
 namespace syncer {
 
-class ProcessorEntityTracker;
+class ProcessorEntity;
 struct EntityData;
 
 namespace syncable {
@@ -91,7 +91,7 @@ class ProtoValuePtr {
  private:
   friend struct syncable::EntryKernel;
   friend struct EntityData;
-  friend class ProcessorEntityTracker;
+  friend class ProcessorEntity;
   FRIEND_TEST_ALL_PREFIXES(ProtoValuePtrTest, ValueAssignment);
   FRIEND_TEST_ALL_PREFIXES(ProtoValuePtrTest, ValueSwap);
   FRIEND_TEST_ALL_PREFIXES(ProtoValuePtrTest, SharingTest);

components/sync/model/entity_data.h

@@ -101,7 +101,7 @@ struct EntityData {
 
   // Makes a copy of EntityData and updates its id to |new_id|. This is needed
   // when entity id is updated with commit response while EntityData for next
-  // local change is cached in ProcessorEntityTracker.
+  // local change is cached in ProcessorEntity.
   EntityDataPtr UpdateId(const std::string& new_id) const WARN_UNUSED_RESULT;
 
   // Makes a copy of EntityData and updates its client tag hash to

components/sync/model_impl/client_tag_based_model_type_processor.h

@@ -33,7 +33,7 @@
 namespace syncer {
 
 class CommitQueue;
-class ProcessorEntityTracker;
+class ProcessorEntity;
 
 // A sync component embedded on the model type's thread that tracks entity
 // metadata in the model store and coordinates communication between sync and
@@ -130,13 +130,13 @@ class ClientTagBasedModelTypeProcessor : public ModelTypeProcessor,
 
   // Helper function to process the update for a single entity. If a local data
   // change is required, it will be added to |entity_changes|. The return value
-  // is the tracker for this entity, or nullptr if the update should be ignored.
-  ProcessorEntityTracker* ProcessUpdate(const UpdateResponseData& update,
-                                        EntityChangeList* entity_changes);
+  // is the tracked entity, or nullptr if the update should be ignored.
+  ProcessorEntity* ProcessUpdate(const UpdateResponseData& update,
+                                 EntityChangeList* entity_changes);
 
   // Resolve a conflict between |update| and the pending commit in |entity|.
   ConflictResolution::Type ResolveConflict(const UpdateResponseData& update,
-                                           ProcessorEntityTracker* entity,
+                                           ProcessorEntity* entity,
                                            EntityChangeList* changes);
 
   // Recommit all entities for encryption except those in |already_updated|.
@@ -170,7 +170,7 @@ class ClientTagBasedModelTypeProcessor : public ModelTypeProcessor,
                            std::unordered_set<std::string> storage_keys_to_load,
                            std::unique_ptr<DataBatch> data_batch);
 
-  // Caches EntityData from the |data_batch| in the entity trackers and checks
+  // Caches EntityData from the |data_batch| in the entity and checks
   // that every entity in |storage_keys_to_load| was successfully loaded (or is
   // not tracked by the processor any more). Reports failed checks to UMA.
   void ConsumeDataBatch(std::unordered_set<std::string> storage_keys_to_load,
@@ -192,26 +192,24 @@ class ClientTagBasedModelTypeProcessor : public ModelTypeProcessor,
                                const EntityData& data) const;
 
   // Gets the entity for the given storage key, or null if there isn't one.
-  ProcessorEntityTracker* GetEntityForStorageKey(
-      const std::string& storage_key);
-  const ProcessorEntityTracker* GetEntityForStorageKey(
+  ProcessorEntity* GetEntityForStorageKey(const std::string& storage_key);
+  const ProcessorEntity* GetEntityForStorageKey(
       const std::string& storage_key) const;
 
   // Gets the entity for the given tag hash, or null if there isn't one.
-  ProcessorEntityTracker* GetEntityForTagHash(const std::string& tag_hash);
-  const ProcessorEntityTracker* GetEntityForTagHash(
-      const std::string& tag_hash) const;
+  ProcessorEntity* GetEntityForTagHash(const std::string& tag_hash);
+  const ProcessorEntity* GetEntityForTagHash(const std::string& tag_hash) const;
 
   // Create an entity in the entity map for |storage_key| and return a pointer
   // to it.
   // Requires that no entity for |storage_key| already exists in the map.
-  ProcessorEntityTracker* CreateEntity(const std::string& storage_key,
-                                       const EntityData& data);
+  ProcessorEntity* CreateEntity(const std::string& storage_key,
+                                const EntityData& data);
 
   // Version of the above that generates a tag for |data|.
-  ProcessorEntityTracker* CreateEntity(const EntityData& data);
+  ProcessorEntity* CreateEntity(const EntityData& data);
 
-  // Returns true if all processor entity trackers have non-empty storage keys.
+  // Returns true if all processor entities have non-empty storage keys.
   bool AllStorageKeysPopulated() const;
 
   // Expires entries according to garbage collection directives.
@@ -243,9 +241,9 @@ class ClientTagBasedModelTypeProcessor : public ModelTypeProcessor,
   void ExpireEntriesByItemLimit(int32_t max_number_of_items,
                                 MetadataChangeList* metadata_changes);
 
-  // Removes entity tracker and clears metadata for entity from
-  // MetadataChangeList.
-  void RemoveEntity(ProcessorEntityTracker* entity,
+  // Removes |entity| and clears metadata for |entity| from
+  // |metadata_change_list|.
+  void RemoveEntity(ProcessorEntity* entity,
                     MetadataChangeList* metadata_change_list);
 
   // Resets the internal state of the processor to the one right after calling
@@ -314,7 +312,7 @@ class ClientTagBasedModelTypeProcessor : public ModelTypeProcessor,
   // A map of client tag hash to sync entities known to this processor. This
   // should contain entries and metadata for most everything, although the
   // entities may not always contain model type data/specifics.
-  std::map<std::string, std::unique_ptr<ProcessorEntityTracker>> entities_;
+  std::map<std::string, std::unique_ptr<ProcessorEntity>> entities_;
 
   // The bridge wants to communicate entirely via storage keys that it is free
   // to define and can understand more easily. All of the sync machinery wants

components/sync/model_impl/client_tag_based_model_type_processor_unittest.cc

@@ -271,8 +271,7 @@ class ClientTagBasedModelTypeProcessorTest : public ::testing::Test {
     return;
   }
 
-  ProcessorEntityTracker* GetEntityForStorageKey(
-      const std::string& storage_key) {
+  ProcessorEntity* GetEntityForStorageKey(const std::string& storage_key) {
     return type_processor()->GetEntityForStorageKey(storage_key);
   }
 
@@ -1949,9 +1948,9 @@ TEST_F(ClientTagBasedModelTypeProcessorTest,
   worker()->VerifyNthPendingCommit(1, {kHash1}, {specifics2});
 }
 
-// Tests that UpdateStorageKey propagates storage key to ProcessorEntityTracker
+// Tests that UpdateStorageKey propagates storage key to ProcessorEntity
 // and updates corresponding entity's metadata in MetadataChangeList, and
-// UntrackEntity will remove corresponding ProcessorEntityTracker and do not add
+// UntrackEntity will remove corresponding ProcessorEntity and do not add
 // any entity's metadata into MetadataChangeList.
 TEST_F(ClientTagBasedModelTypeProcessorTest, ShouldUpdateStorageKey) {
   // Setup bridge to not support calls to GetStorageKey. This will cause
@@ -2010,7 +2009,7 @@ TEST_F(ClientTagBasedModelTypeProcessorTest,
 }
 
 // Tests that UntrackEntity won't propagate storage key to
-// ProcessorEntityTracker, and no entity's metadata are added into
+// ProcessorEntity, and no entity's metadata are added into
 // MetadataChangeList.
 TEST_F(ClientTagBasedModelTypeProcessorTest, ShouldUntrackEntity) {
   // Setup bridge to not support calls to GetStorageKey. This will cause
@@ -2026,7 +2025,7 @@ TEST_F(ClientTagBasedModelTypeProcessorTest, ShouldUntrackEntity) {
   EXPECT_EQ(1, bridge()->merge_call_count());
   EXPECT_EQ(0U, ProcessorEntityCount());
   // Metadata should not be written under kUntrackKey1. This means that
-  // UntrackEntity was called and corresponding ProcessorEntityTracker is
+  // UntrackEntity was called and corresponding ProcessorEntity is
   // removed and no storage key got propagated to MetadataChangeList.
   EXPECT_FALSE(db()->HasMetadata(kHash1));
   EXPECT_EQ(0U, db()->metadata_count());
@@ -2034,7 +2033,7 @@ TEST_F(ClientTagBasedModelTypeProcessorTest, ShouldUntrackEntity) {
 }
 
 // Tests that UntrackEntityForStorage won't propagate storage key to
-// ProcessorEntityTracker, and no entity's metadata are added into
+// ProcessorEntity, and no entity's metadata are added into
 // MetadataChangeList.
 TEST_F(ClientTagBasedModelTypeProcessorTest, ShouldUntrackEntityForStorageKey) {
   InitializeToReadyState();

components/sync/model_impl/processor_entity_tracker.h → components/sync/model_impl/processor_entity.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_TRACKER_H_
-#define COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_TRACKER_H_
+#ifndef COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_H_
+#define COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_H_
 
 #include <stdint.h>
 
@@ -25,10 +25,10 @@ struct UpdateResponseData;
 // of each entity with its type. It can be considered a helper class internal to
 // the processor. It manages the metadata for its entity and caches entity data
 // upon a local change until commit confirmation is received.
-class ProcessorEntityTracker {
+class ProcessorEntity {
  public:
   // Construct an instance representing a new locally-created item.
-  static std::unique_ptr<ProcessorEntityTracker> CreateNew(
+  static std::unique_ptr<ProcessorEntity> CreateNew(
       const std::string& storage_key,
       const std::string& client_tag_hash,
       const std::string& id,
@@ -36,11 +36,11 @@ class ProcessorEntityTracker {
 
   // Construct an instance representing an item loaded from storage on init.
   // This method swaps out the contents of |metadata|.
-  static std::unique_ptr<ProcessorEntityTracker> CreateFromMetadata(
+  static std::unique_ptr<ProcessorEntity> CreateFromMetadata(
       const std::string& storage_key,
       sync_pb::EntityMetadata* metadata);
 
-  ~ProcessorEntityTracker();
+  ~ProcessorEntity();
 
   const std::string& storage_key() const { return storage_key_; }
   const sync_pb::EntityMetadata& metadata() const { return metadata_; }
@@ -108,7 +108,7 @@ class ProcessorEntityTracker {
 
   // Update storage_key_. Allows setting storage key for datatypes that don't
   // generate storage key from syncer::EntityData. Should only be called for
-  // tracker initialized with empty storage key.
+  // an entity initialized with empty storage key.
   void SetStorageKey(const std::string& storage_key);
 
   // Takes the passed commit data updates its fields with values from metadata
@@ -137,11 +137,11 @@ class ProcessorEntityTracker {
   size_t EstimateMemoryUsage() const;
 
  private:
-  friend class ProcessorEntityTrackerTest;
+  friend class ProcessorEntityTest;
 
   // The constructor swaps the data from the passed metadata.
-  ProcessorEntityTracker(const std::string& storage_key,
-                         sync_pb::EntityMetadata* metadata);
+  ProcessorEntity(const std::string& storage_key,
+                  sync_pb::EntityMetadata* metadata);
 
   // Check whether |specifics| matches the stored specifics_hash.
   bool MatchesSpecificsHash(const sync_pb::EntitySpecifics& specifics) const;
@@ -171,4 +171,4 @@ class ProcessorEntityTracker {
 
 }  // namespace syncer
 
-#endif  // COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_TRACKER_H_
+#endif  // COMPONENTS_SYNC_MODEL_IMPL_PROCESSOR_ENTITY_H_

docs/sync/uss/client_tag_based_model_type_processor.md

@@ -106,7 +106,7 @@ progresses through 3 states worth noting:
 
 ## Entity Tracker
 
-The [`ProcessorEntityTracker`][PET] tracks the state of individual entities for
+The [`ProcessorEntity`][PET] tracks the state of individual entities for
 the processor. It keeps the [`EntityMetadata`][EM] proto in memory, as well as
 any pending commit data until it gets acked by the server. It also stores the
 special `commit_requested_sequence_number_`, which tracks the sequence number of
@@ -116,5 +116,5 @@ The tracker holds the metadata in memory forever, which is needed so we know
 what to update the on-disk memory with when we get a new local or remote change.
 Changing this would require being able to handle updates asynchronously.
 
-[PET]: https://cs.chromium.org/chromium/src/components/sync/model_impl/processor_entity_tracker.h
+[PET]: https://cs.chromium.org/chromium/src/components/sync/model_impl/processor_entity.h
 [EM]: https://cs.chromium.org/chromium/src/components/sync/protocol/entity_metadata.proto