Pref service: Add a ScopedDictionaryPrefUpdate to track value changes.

services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc

Index: services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc
diff --git a/services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc b/services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..47c408112cc9fe49afc0b7d80b105c34b4a3b2d6
--- /dev/null
+++ b/services/preferences/public/cpp/tests/persistent_pref_store_client_unittest.cc
@@ -0,0 +1,500 @@
+// Copyright 2017 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 "services/preferences/public/cpp/persistent_pref_store_client.h"
+
+#include <utility>
+
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "base/values.h"
+#include "components/prefs/pref_notifier_impl.h"
+#include "components/prefs/pref_registry_simple.h"
+#include "components/prefs/pref_service.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+#include "services/preferences/public/cpp/scoped_pref_update.h"
+#include "services/preferences/public/interfaces/preferences.mojom.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace prefs {
+namespace {
+
+constexpr char kDictionaryKey[] = "path.to.key";
+constexpr char kUninitializedDictionaryKey[] = "path.to.an.uninitialized.dict";
+
+void DoNothingWithReadError(::PersistentPrefStore::PrefReadError read_error) {}
+
+class PersistentPrefStoreClientTest : public testing::Test,
+                                      public mojom::PersistentPrefStore {
+ public:
+  PersistentPrefStoreClientTest() : binding_(this) {}
+
+  // testing::Test:
+  void SetUp() override {
+    auto persistent_pref_store_client = make_scoped_refptr(
+        new PersistentPrefStoreClient(mojom::PersistentPrefStoreConnection::New(
+            mojom::PrefStoreConnection::New(
+                mojom::PrefStoreObserverRequest(),
+                base::MakeUnique<base::DictionaryValue>(), true),
+            binding_.CreateInterfacePtrAndBind(),
+            ::PersistentPrefStore::PREF_READ_ERROR_NONE, false)));
+    auto pref_registry = make_scoped_refptr(new PrefRegistrySimple());
+    pref_registry->RegisterDictionaryPref(kDictionaryKey);
+    pref_registry->RegisterDictionaryPref(kUninitializedDictionaryKey);
+    PrefNotifierImpl* pref_notifier = new PrefNotifierImpl;
+    pref_service_ = base::MakeUnique<PrefService>(
+        pref_notifier,
+        new PrefValueStore(nullptr, nullptr, nullptr, nullptr, nullptr, nullptr,
+                           nullptr, pref_notifier),
+        persistent_pref_store_client.get(), pref_registry.get(),
+        base::Bind(&DoNothingWithReadError), false);
+    { ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey); }
+    auto update = WaitForUpdate();
+    ASSERT_TRUE(update->is_atomic_update());
+    EXPECT_EQ(base::DictionaryValue(), *update->get_atomic_update());
+  }
+
+  void TearDown() override {
+    pref_service_ = nullptr;
+    base::RunLoop().RunUntilIdle();
+    binding_.Close();
+    base::RunLoop().RunUntilIdle();
+  }
+
+  PrefService* pref_service() { return pref_service_.get(); }
+
+  mojom::PrefUpdateValuePtr WaitForUpdate() {
+    base::RunLoop run_loop;
+    on_update_ = run_loop.QuitClosure();
+    run_loop.Run();
+    EXPECT_EQ(1u, last_updates_.size());
+    auto result = std::move(last_updates_[0]->value);
+    last_updates_.clear();
+    return result;
+  }
+
+  void ExpectNoUpdate() {
+    binding_.FlushForTesting();
+    EXPECT_TRUE(last_updates_.empty());
+  }
+
+ private:
+  void SetValues(std::vector<mojom::PrefUpdatePtr> updates) override {
+    last_updates_ = std::move(updates);
+    if (on_update_)
+      std::move(on_update_).Run();
+  }
+
+  void CommitPendingWrite() override {}
+  void SchedulePendingLossyWrites() override {}
+  void ClearMutableValues() override {}
+
+  base::MessageLoop message_loop_;
+
+  std::unique_ptr<PrefService> pref_service_;
+
+  mojo::Binding<mojom::PersistentPrefStore> binding_;
+
+  std::vector<mojom::PrefUpdatePtr> last_updates_;
+  base::OnceClosure on_update_;
+
+  DISALLOW_COPY_AND_ASSIGN(PersistentPrefStoreClientTest);
+};
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_Basic) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::Value(1), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_BasicWithoutPathExpansion) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetIntegerWithoutPathExpansion("key.for.integer", 1);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  EXPECT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::Value(1), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"key.for.integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_Remove) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.another_integer", 1);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->Remove("path.to.integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_RemoveWithoutPathExpansion) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetIntegerWithoutPathExpansion("path.to.another_integer", 1);
+    update->SetIntegerWithoutPathExpansion("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemoveWithoutPathExpansion("path.to.integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path.to.integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_MultipleUpdates) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetDoubleWithoutPathExpansion("a.double", 1);
+  }
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 2);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(2u, split_updates.size());
+  EXPECT_EQ(base::Value(1.0), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"a.double"}), split_updates[0]->path);
+  EXPECT_EQ(base::Value(2), *split_updates[1]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "integer"}),
+            split_updates[1]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_NestedUpdateAfterSet) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    DictionaryValueUpdate* dict;
+    ASSERT_TRUE(update->GetDictionary("path.to", &dict));
+    dict->Clear();
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::DictionaryValue(), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_NestedUpdateBeforeSet) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->Set("path.to", base::MakeUnique<base::DictionaryValue>());
+  }
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  base::DictionaryValue expected_value;
+  expected_value.SetInteger("integer", 1);
+  EXPECT_EQ(expected_value, *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_DoubleNestedUpdate) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    DictionaryValueUpdate* dict;
+    ASSERT_TRUE(update->GetDictionary("path", &dict));
+    dict->Clear();
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::DictionaryValue(), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_ManualNesting) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    DictionaryValueUpdate* dict = nullptr;
+    ASSERT_TRUE(update->GetDictionary("path.to", &dict));
+    dict->SetString("string", "string value");
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::Value("string value"), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "string"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_ManualDictCreationAndNesting) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    auto* dict = update->SetDictionary(
+        "path.to", base::MakeUnique<base::DictionaryValue>());
+    dict->SetString("string", "string value");
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  base::DictionaryValue expected_value;
+  expected_value.SetString("string", "string value");
+  EXPECT_EQ(expected_value, *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_ManualDictCreationWithoutPathExpansionAndNesting) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    auto* dict = update->SetDictionaryWithoutPathExpansion(
+        "a.dictionary", base::MakeUnique<base::DictionaryValue>());
+    dict->SetStringWithoutPathExpansion("a.string", "string value");
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  base::DictionaryValue expected_value;
+  expected_value.SetStringWithoutPathExpansion("a.string", "string value");
+  EXPECT_EQ(expected_value, *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"a.dictionary"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_AsDictionaryTriggersFullWrite) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+    update->AsDictionary();
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_atomic_update());
+  base::DictionaryValue expected_value;
+  expected_value.SetInteger("path.to.integer", 1);
+  EXPECT_EQ(expected_value, *update->get_atomic_update());
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_AsConstDictionaryIsNoOp) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+    update->AsConstDictionary();
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::Value(1), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_RemovePath_Basic) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+    update->SetInteger("path.to.something.else", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemovePath("path.to.integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to", "integer"}),
+            split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_RemovePath_RemoveContainingDict) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+    update->SetInteger("path.for.something.else", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemovePath("path.to.integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path", "to"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_RemovePath_SinglePathComponent) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("integer", 1);
+    update->SetInteger("something_else", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemovePath("integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"integer"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_RemovePath_FullPref) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemovePath("path.to.integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest,
+       SubPrefUpdates_RemovePathSinglePathComponent_FullPref) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->RemovePath("integer", nullptr);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_FALSE(split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"integer"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_NoChange) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  { ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey); }
+  ExpectNoUpdate();
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_SetToExistingValue) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  ExpectNoUpdate();
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_ClearEmptyDictionary) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->Clear();
+  }
+  ExpectNoUpdate();
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_ReplaceDictionary) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  WaitForUpdate();
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(), kDictionaryKey);
+    update->SetInteger("path", 2);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_split_updates());
+  auto& split_updates = update->get_split_updates();
+  ASSERT_EQ(1u, split_updates.size());
+  EXPECT_EQ(base::Value(2), *split_updates[0]->value);
+  EXPECT_EQ((std::vector<std::string>{"path"}), split_updates[0]->path);
+}
+
+TEST_F(PersistentPrefStoreClientTest, SubPrefUpdates_Uninitialized) {
+  {
+    ScopedDictionaryPrefUpdate update(pref_service(),
+                                      kUninitializedDictionaryKey);
+    update->SetInteger("path.to.integer", 1);
+  }
+  auto update = WaitForUpdate();
+  ASSERT_TRUE(update->is_atomic_update());
+  base::DictionaryValue expected_value;
+  expected_value.SetInteger("path.to.integer", 1);
+  EXPECT_EQ(expected_value, *update->get_atomic_update());
+}
+
+}  // namespace
+}  // namespace prefs