Create a strict order in ReadingListSpecifics

components/reading_list/ios/reading_list_store_unittest.mm

 // Copyright 2016 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 "components/reading_list/ios/reading_list_store.h"
 
 #include <map>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 237 matching lines @@
       reading_list_store_->CreateMetadataChangeList(), add_changes);
   AssertCounts(1, 0, 0, 0, 1);
   EXPECT_EQ(sync_merged_.size(), 1u);
   EXPECT_EQ(sync_merged_.count("http://unread.example.com/"), 1u);
   EXPECT_EQ(sync_merged_["http://unread.example.com/"], true);
 }
 
 TEST_F(ReadingListStoreTest, ApplySyncChangesOneIgnored) {
   // Read entry but with unread URL as it must update the other one.
   ReadingListEntry old_entry(GURL("http://unread.example.com/"),
-                             "unread title");
+                             "old unread title");
   old_entry.SetRead(true);
 
   base::test::ios::SpinRunLoopWithMinDelay(
       base::TimeDelta::FromMilliseconds(10));
   syncer::EntityDataMap remote_input;
-  model_->AddEntry(GURL("http://unread.example.com/"), "unread title");
+  model_->AddEntry(GURL("http://unread.example.com/"), "new unread title");
   AssertCounts(0, 0, 0, 0, 0);
 
   std::unique_ptr<sync_pb::ReadingListSpecifics> specifics =
       old_entry.AsReadingListSpecifics();
   syncer::EntityData data;
   data.client_tag_hash = "http://unread.example.com/";
   *data.specifics.mutable_reading_list() = *specifics;
 
   syncer::EntityChangeList add_changes;
   add_changes.push_back(syncer::EntityChange::CreateAdd(
       "http://unread.example.com/", data.PassToPtr()));
   syncer::SyncError error = reading_list_store_->ApplySyncChanges(
       reading_list_store_->CreateMetadataChangeList(), add_changes);
-  AssertCounts(1, 0, 0, 0, 0);
-  EXPECT_EQ(sync_merged_.size(), 0u);
+  AssertCounts(1, 0, 0, 0, 1);
+  EXPECT_EQ(sync_merged_.size(), 1u);
+  EXPECT_EQ(model_->GetEntryByURL(GURL("http://unread.example.com/"))->Title(),
+            "new unread title");
 }
 
 TEST_F(ReadingListStoreTest, ApplySyncChangesOneRemove) {
   syncer::EntityChangeList delete_changes;
   delete_changes.push_back(
       syncer::EntityChange::CreateDelete("http://read.example.com/"));
   syncer::SyncError error = reading_list_store_->ApplySyncChanges(
       reading_list_store_->CreateMetadataChangeList(), delete_changes);
   AssertCounts(0, 0, 0, 1, 0);
   EXPECT_EQ(sync_removed_.size(), 1u);
   EXPECT_EQ(sync_removed_.count("http://read.example.com/"), 1u);
 }
+
+TEST_F(ReadingListStoreTest, CompareEntriesForSync) {
+  sync_pb::ReadingListSpecifics entryA;
+  sync_pb::ReadingListSpecifics entryB;
+  entryA.set_url("http://foo.bar");
+  entryB.set_url("http://foo.bar");
+  entryA.set_title("Foo Bar");
+  entryB.set_title("Foo Bar");
+  entryA.set_status(sync_pb::ReadingListSpecifics::UNREAD);
+  entryB.set_status(sync_pb::ReadingListSpecifics::UNREAD);
+  entryA.set_creation_time_us(10);
+  entryB.set_creation_time_us(10);
+  entryA.set_update_time_us(100);
+  entryB.set_update_time_us(100);
+  // Equal entries can be submitted.
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+
+  // Try to update each field.
+  entryA.set_url("http://foo.foo");
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_update_time_us(110);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_url("http://foo.bar");
+  entryA.set_update_time_us(100);
+
+  entryA.set_title("foo bar");
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_update_time_us(110);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_title("Foo Bar");
+  entryA.set_update_time_us(100);
+
+  entryA.set_creation_time_us(15);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_update_time_us(110);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_creation_time_us(10);
+  entryA.set_update_time_us(100);
+
+  entryA.set_status(sync_pb::ReadingListSpecifics::READ);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_update_time_us(110);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_status(sync_pb::ReadingListSpecifics::UNREAD);
+  entryA.set_update_time_us(100);
+
+  entryA.set_status(sync_pb::ReadingListSpecifics::UNSEEN);
+  // Special case UNSEEN -> SEEN status
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_update_time_us(110);
+  EXPECT_FALSE(ReadingListStore::CompareEntriesForSync(entryA, entryB));
+  EXPECT_TRUE(ReadingListStore::CompareEntriesForSync(entryB, entryA));
+  entryA.set_status(sync_pb::ReadingListSpecifics::UNREAD);
+  entryA.set_update_time_us(100);
+}