Pref service: add persistent pref store frontend and backend.

services/preferences/persistent_pref_store_impl_unittest.cc

Index: services/preferences/persistent_pref_store_impl_unittest.cc
diff --git a/services/preferences/persistent_pref_store_impl_unittest.cc b/services/preferences/persistent_pref_store_impl_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..806a3428e9b0d8b14c487b5b54fd6db8b71aee5b
--- /dev/null
+++ b/services/preferences/persistent_pref_store_impl_unittest.cc
@@ -0,0 +1,459 @@
+// 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/persistent_pref_store_impl.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/in_memory_pref_store.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+#include "services/preferences/public/cpp/persistent_pref_store_client.h"
+#include "services/preferences/public/interfaces/preferences.mojom.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using testing::Invoke;
+using testing::WithoutArgs;
+
+namespace prefs {
+namespace {
+
+class PrefStoreObserverMock : public PrefStore::Observer {
+ public:
+  MOCK_METHOD1(OnPrefValueChanged, void(const std::string&));
+  MOCK_METHOD1(OnInitializationCompleted, void(bool succeeded));
+};
+
+class PersistentPrefStoreMock : public InMemoryPrefStore {
+ public:
+  MOCK_METHOD0(CommitPendingWrite, void());
+  MOCK_METHOD0(SchedulePendingLossyWrites, void());
+  MOCK_METHOD0(ClearMutableValues, void());
+
+ private:
+  ~PersistentPrefStoreMock() override = default;
+};
+
+class PrefStoreConnectorMock : public mojom::PrefStoreConnector {
+ public:
+  MOCK_METHOD1(Connect, void(const ConnectCallback&));
+};
+
+class InitializationMockPersistentPrefStore : public InMemoryPrefStore {
+ public:
+  bool IsInitializationComplete() const override { return initialized_; }
+
+  void AddObserver(PrefStore::Observer* observer) override {
+    observers_.AddObserver(observer);
+  }
+
+  void RemoveObserver(PrefStore::Observer* observer) override {
+    observers_.RemoveObserver(observer);
+  }
+
+  void ReadPrefsAsync(ReadErrorDelegate* error_delegate) override {
+    DCHECK(!error_delegate);
+  }
+
+  PersistentPrefStore::PrefReadError GetReadError() const override {
+    return read_error_;
+  }
+  bool ReadOnly() const override { return read_only_; }
+
+  void Initialize(bool success,
+                  PersistentPrefStore::PrefReadError error,
+                  bool read_only) {
+    initialized_ = success;
+    read_error_ = error;
+    read_only_ = read_only;
+    for (auto& observer : observers_) {
+      observer.OnInitializationCompleted(initialized_);
+    }
+  }
+
+ private:
+  ~InitializationMockPersistentPrefStore() override = default;
+
+  PersistentPrefStore::PrefReadError read_error_;
+  bool read_only_ = false;
+  bool initialized_ = false;
+  base::ObserverList<PrefStore::Observer, true> observers_;
+};
+
+class PersistentPrefStoreImplTest : public testing::Test {
+ public:
+  PersistentPrefStoreImplTest() = default;
+
+  // testing::Test:
+  void TearDown() override {
+    pref_store_ = nullptr;
+    base::RunLoop().RunUntilIdle();
+    bindings_.CloseAllBindings();
+    backing_pref_store_.reset();
+    base::RunLoop().RunUntilIdle();
+  }
+
+  void CreateImpl(scoped_refptr<PersistentPrefStore> backing_pref_store) {
+    backing_pref_store_ = base::MakeUnique<PersistentPrefStoreImpl>(
+        std::move(backing_pref_store), nullptr);
+    mojo::Binding<mojom::PersistentPrefStoreConnector> binding(
+        backing_pref_store_.get());
+    pref_store_ = CreateConnection();
+  }
+
+  mojom::PersistentPrefStoreConnectorPtr CreateConnector() {
+    return bindings_.CreateInterfacePtrAndBind(backing_pref_store_.get());
+  }
+
+  scoped_refptr<PersistentPrefStore> CreateConnection() {
+    return make_scoped_refptr(new PersistentPrefStoreClient(
+        bindings_.CreateInterfacePtrAndBind(backing_pref_store_.get())));
+  }
+
+  PersistentPrefStore* pref_store() { return pref_store_.get(); }
+
+ private:
+  base::MessageLoop message_loop_;
+
+  std::unique_ptr<PersistentPrefStoreImpl> backing_pref_store_;
+  mojo::BindingSet<mojom::PersistentPrefStoreConnector> bindings_;
+
+  scoped_refptr<PersistentPrefStore> pref_store_;
+
+  DISALLOW_COPY_AND_ASSIGN(PersistentPrefStoreImplTest);
+};
+
+TEST_F(PersistentPrefStoreImplTest, InitializationSuccess) {
+  auto backing_pref_store =
+      make_scoped_refptr(new InitializationMockPersistentPrefStore);
+  CreateImpl(backing_pref_store);
+  backing_pref_store->Initialize(
+      true, PersistentPrefStore::PREF_READ_ERROR_NONE, false);
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->GetReadError());
+  EXPECT_FALSE(pref_store()->ReadOnly());
+}
+
+TEST_F(PersistentPrefStoreImplTest, InitializationFailure) {
+  auto backing_pref_store =
+      make_scoped_refptr(new InitializationMockPersistentPrefStore);
+  CreateImpl(backing_pref_store);
+  backing_pref_store->Initialize(
+      false, PersistentPrefStore::PREF_READ_ERROR_JSON_PARSE, true);
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_JSON_PARSE,
+            pref_store()->ReadPrefs());
+  EXPECT_FALSE(pref_store()->IsInitializationComplete());
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_JSON_PARSE,
+            pref_store()->GetReadError());
+  EXPECT_TRUE(pref_store()->ReadOnly());
+}
+
+class TestReadErrorDelegate : public PersistentPrefStore::ReadErrorDelegate {
+ public:
+  TestReadErrorDelegate(PersistentPrefStore::PrefReadError* storage,
+                        const base::Closure& quit)
+      : storage_(storage), quit_(quit) {
+    DCHECK(storage_);
+    DCHECK(quit_);
+  }
+
+  void OnError(PersistentPrefStore::PrefReadError error) override {
+    *storage_ = error;
+    quit_.Run();
+  }
+
+ private:
+  PersistentPrefStore::PrefReadError* const storage_;
+  const base::Closure quit_;
+};
+
+TEST_F(PersistentPrefStoreImplTest, InitializationFailure_AsyncRead) {
+  auto backing_pref_store =
+      make_scoped_refptr(new InitializationMockPersistentPrefStore);
+  CreateImpl(backing_pref_store);
+  backing_pref_store->Initialize(
+      false, PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE, true);
+  PersistentPrefStore::PrefReadError read_error =
+      PersistentPrefStore::PREF_READ_ERROR_NONE;
+  base::RunLoop run_loop;
+  pref_store()->ReadPrefsAsync(
+      new TestReadErrorDelegate(&read_error, run_loop.QuitClosure()));
+  run_loop.Run();
+  EXPECT_FALSE(pref_store()->IsInitializationComplete());
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE, read_error);
+  EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_JSON_TYPE,
+            pref_store()->GetReadError());
+  EXPECT_TRUE(pref_store()->ReadOnly());
+}
+
+TEST_F(PersistentPrefStoreImplTest, DelayedInitializationSuccess) {
+  auto backing_pref_store =
+      make_scoped_refptr(new InitializationMockPersistentPrefStore);
+
+  CreateImpl(backing_pref_store);
+  auto connector = CreateConnector();
+  base::RunLoop run_loop;
+  connector->Connect(base::Bind(
+      [](const base::Closure& quit,
+         PersistentPrefStore::PrefReadError read_error, bool read_only,
+         std::unique_ptr<base::DictionaryValue> local_prefs,
+         mojom::PersistentPrefStorePtr pref_store,
+         mojom::PrefStoreObserverRequest observer_request) {
+        quit.Run();
+        EXPECT_FALSE(read_only);
+        EXPECT_TRUE(local_prefs);
+        EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE, read_error);
+      },
+      run_loop.QuitClosure()));
+  connector.FlushForTesting();
+  backing_pref_store->Initialize(
+      true, PersistentPrefStore::PREF_READ_ERROR_NONE, false);
+  run_loop.Run();
+}
+
+TEST_F(PersistentPrefStoreImplTest, DelayedInitializationFailure) {
+  auto backing_pref_store =
+      make_scoped_refptr(new InitializationMockPersistentPrefStore);
+
+  CreateImpl(backing_pref_store);
+  auto connector = CreateConnector();
+  base::RunLoop run_loop;
+  connector->Connect(base::Bind(
+      [](const base::Closure& quit,
+         PersistentPrefStore::PrefReadError read_error, bool read_only,
+         std::unique_ptr<base::DictionaryValue> local_prefs,
+         mojom::PersistentPrefStorePtr pref_store,
+         mojom::PrefStoreObserverRequest observer_request) {
+        quit.Run();
+        EXPECT_TRUE(read_only);
+        EXPECT_FALSE(local_prefs);
+        EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_ACCESS_DENIED,
+                  read_error);
+      },
+      run_loop.QuitClosure()));
+  connector.FlushForTesting();
+  backing_pref_store->Initialize(
+      false, PersistentPrefStore::PREF_READ_ERROR_ACCESS_DENIED, true);
+  run_loop.Run();
+}
+
+constexpr char kKey[] = "path.to.key";
+
+TEST_F(PersistentPrefStoreImplTest, InitialValue) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  const base::Value value("value");
+  backing_pref_store->SetValue(kKey, value.CreateDeepCopy(), 0);
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(pref_store()->GetValue(kKey, &output));
+  EXPECT_TRUE(value.Equals(output));
+}
+
+TEST_F(PersistentPrefStoreImplTest, InitialValueWithoutPathExpansion) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  base::DictionaryValue dict;
+  dict.SetStringWithoutPathExpansion(kKey, "value");
+  backing_pref_store->SetValue(kKey, dict.CreateDeepCopy(), 0);
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(pref_store()->GetValue(kKey, &output));
+  EXPECT_TRUE(dict.Equals(output));
+}
+
+TEST_F(PersistentPrefStoreImplTest, WriteObservedByOtherClient) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+
+  auto other_pref_store = CreateConnection();
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            other_pref_store->ReadPrefs());
+  EXPECT_TRUE(other_pref_store->IsInitializationComplete());
+
+  const base::Value value("value");
+  pref_store()->SetValueSilently(kKey, value.CreateDeepCopy(), 0);
+
+  PrefStoreObserverMock observer;
+  other_pref_store->AddObserver(&observer);
+  base::RunLoop run_loop;
+  EXPECT_CALL(observer, OnPrefValueChanged(kKey))
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  run_loop.Run();
+  other_pref_store->RemoveObserver(&observer);
+
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(other_pref_store->GetValue(kKey, &output));
+  EXPECT_TRUE(value.Equals(output));
+}
+
+TEST_F(PersistentPrefStoreImplTest,
+       WriteWithoutPathExpansionObservedByOtherClient) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+
+  auto other_pref_store = CreateConnection();
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            other_pref_store->ReadPrefs());
+  EXPECT_TRUE(other_pref_store->IsInitializationComplete());
+
+  base::DictionaryValue dict;
+  dict.SetStringWithoutPathExpansion(kKey, "value");
+  pref_store()->SetValue(kKey, dict.CreateDeepCopy(), 0);
+
+  PrefStoreObserverMock observer;
+  other_pref_store->AddObserver(&observer);
+  base::RunLoop run_loop;
+  EXPECT_CALL(observer, OnPrefValueChanged(kKey))
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  run_loop.Run();
+  other_pref_store->RemoveObserver(&observer);
+
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(other_pref_store->GetValue(kKey, &output));
+  EXPECT_TRUE(dict.Equals(output));
+}
+
+TEST_F(PersistentPrefStoreImplTest, RemoveObservedByOtherClient) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  const base::Value value("value");
+  backing_pref_store->SetValue(kKey, value.CreateDeepCopy(), 0);
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+
+  auto other_pref_store = CreateConnection();
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            other_pref_store->ReadPrefs());
+  EXPECT_TRUE(other_pref_store->IsInitializationComplete());
+
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(other_pref_store->GetValue(kKey, &output));
+  EXPECT_TRUE(value.Equals(output));
+  pref_store()->RemoveValue(kKey, 0);
+
+  // This should be a no-op and shouldn't trigger a notification for the other
+  // client.
+  pref_store()->RemoveValue(kKey, 0);
+
+  PrefStoreObserverMock observer;
+  other_pref_store->AddObserver(&observer);
+  base::RunLoop run_loop;
+  EXPECT_CALL(observer, OnPrefValueChanged(kKey))
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  run_loop.Run();
+  base::RunLoop().RunUntilIdle();
+  other_pref_store->RemoveObserver(&observer);
+
+  EXPECT_FALSE(other_pref_store->GetValue(kKey, &output));
+}
+
+TEST_F(PersistentPrefStoreImplTest,
+       RemoveWithoutPathExpansionObservedByOtherClient) {
+  auto backing_pref_store = make_scoped_refptr(new InMemoryPrefStore());
+  base::DictionaryValue dict;
+  dict.SetStringWithoutPathExpansion(kKey, "value");
+  backing_pref_store->SetValue(kKey, dict.CreateDeepCopy(), 0);
+  CreateImpl(backing_pref_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  EXPECT_TRUE(pref_store()->IsInitializationComplete());
+
+  auto other_pref_store = CreateConnection();
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            other_pref_store->ReadPrefs());
+  EXPECT_TRUE(other_pref_store->IsInitializationComplete());
+
+  const base::Value* output = nullptr;
+  ASSERT_TRUE(other_pref_store->GetValue(kKey, &output));
+  EXPECT_TRUE(dict.Equals(output));
+
+  base::Value* mutable_value = nullptr;
+  dict.SetStringWithoutPathExpansion(kKey, "value");
+  ASSERT_TRUE(pref_store()->GetMutableValue(kKey, &mutable_value));
+  base::DictionaryValue* mutable_dict = nullptr;
+  ASSERT_TRUE(mutable_value->GetAsDictionary(&mutable_dict));
+  mutable_dict->RemoveWithoutPathExpansion(kKey, nullptr);
+  pref_store()->ReportValueChanged(kKey, 0);
+
+  PrefStoreObserverMock observer;
+  other_pref_store->AddObserver(&observer);
+  base::RunLoop run_loop;
+  EXPECT_CALL(observer, OnPrefValueChanged(kKey))
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  run_loop.Run();
+  other_pref_store->RemoveObserver(&observer);
+
+  ASSERT_TRUE(other_pref_store->GetValue(kKey, &output));
+  const base::DictionaryValue* dict_value = nullptr;
+  ASSERT_TRUE(output->GetAsDictionary(&dict_value));
+  EXPECT_TRUE(dict_value->empty());
+}
+
+TEST_F(PersistentPrefStoreImplTest, CommitPendingWrite) {
+  auto backing_store = make_scoped_refptr(new PersistentPrefStoreMock);
+  CreateImpl(backing_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  base::RunLoop run_loop;
+  EXPECT_CALL(*backing_store, CommitPendingWrite())
+      .Times(2)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  pref_store()->CommitPendingWrite();
+  run_loop.Run();
+}
+
+TEST_F(PersistentPrefStoreImplTest, SchedulePendingLossyWrites) {
+  auto backing_store = make_scoped_refptr(new PersistentPrefStoreMock);
+  CreateImpl(backing_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  base::RunLoop run_loop;
+  EXPECT_CALL(*backing_store, SchedulePendingLossyWrites())
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  EXPECT_CALL(*backing_store, CommitPendingWrite()).Times(1);
+  pref_store()->SchedulePendingLossyWrites();
+  run_loop.Run();
+}
+
+TEST_F(PersistentPrefStoreImplTest, ClearMutableValues) {
+  auto backing_store = make_scoped_refptr(new PersistentPrefStoreMock);
+  CreateImpl(backing_store);
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE,
+            pref_store()->ReadPrefs());
+  base::RunLoop run_loop;
+  EXPECT_CALL(*backing_store, ClearMutableValues())
+      .Times(1)
+      .WillOnce(WithoutArgs(Invoke([&run_loop]() { run_loop.Quit(); })));
+  EXPECT_CALL(*backing_store, CommitPendingWrite()).Times(1);
+  pref_store()->ClearMutableValues();
+  run_loop.Run();
+}
+
+}  // namespace
+}  // namespace prefs