Introduce the NotificationDatabase class.

content/browser/notifications/notification_database_unittest.cc

+// Copyright 2015 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 "content/browser/notifications/notification_database.h"
+
+#include "base/files/scoped_temp_dir.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+namespace {
+
+// Creates a new NotificationDatabase instance in memory.

[Bernhard Bauer, 2015/03/11 17:15:23]

Move this into the test fixture, or move the methods from the fixture here?

[Peter Beverloo, 2015/03/11 18:01:26]

Moved them to the fixture. I'm having the utility methods there to avoid needing
a gazillion FRIEND_TEST_ALL_PREFIXESs.

+NotificationDatabase* CreateDatabaseInMemory() {
+  return new NotificationDatabase(base::FilePath());
+}
+
+// Creates a new NotificationDatabase instance in |path|.
+NotificationDatabase* CreateDatabaseOnFileSystem(
+    const base::FilePath& path) {
+  return new NotificationDatabase(path);
+}
+
+}  // namespace
+
+class NotificationDatabaseTest : public ::testing::Test {
+ protected:
+  // Returns if |database| exists and has been opened.
+  bool IsDatabaseOpen(NotificationDatabase* database) {
+    return database && database->IsOpen();

[Bernhard Bauer, 2015/03/11 17:15:22]

What is the null check for here? It looks like in almost all cases you
dereference the |database| before this anyway.

[Peter Beverloo, 2015/03/11 18:01:26]

Removed it.

+  }
+
+  // Returns if |database| exists and is an in-memory only database.
+  bool IsInMemoryDatabase(NotificationDatabase* database) {
+    return database && database->IsInMemoryDatabase();
+  }
+};
+
+TEST_F(NotificationDatabaseTest, OpenCloseMemory) {
+  scoped_ptr<NotificationDatabase> database(CreateDatabaseInMemory());
+
+  // Should return false because the database does not exist in memory.
+  EXPECT_EQ(NotificationDatabase::STATUS_ERROR_NOT_FOUND,
+            database->Open(false /* create_if_missing */));
+
+  // Should return true, indicating that the database could be created.
+  EXPECT_EQ(NotificationDatabase::STATUS_OK,
+            database->Open(true /* create_if_missing */));
+
+  EXPECT_TRUE(IsDatabaseOpen(database.get()));
+  EXPECT_TRUE(IsInMemoryDatabase(database.get()));
+
+  // Verify that in-memory databases do not persist when being re-created.
+  database.reset(CreateDatabaseInMemory());
+
+  EXPECT_EQ(NotificationDatabase::STATUS_ERROR_NOT_FOUND,
+            database->Open(false /* create_if_missing */));
+}
+
+TEST_F(NotificationDatabaseTest, OpenCloseFileSystem) {
+  base::ScopedTempDir database_dir;
+  ASSERT_TRUE(database_dir.CreateUniqueTempDir());
+
+  scoped_ptr<NotificationDatabase> database(
+      CreateDatabaseOnFileSystem(database_dir.path()));
+
+  // Should return false because the database does not exist on the file system.
+  EXPECT_EQ(NotificationDatabase::STATUS_ERROR_NOT_FOUND,
+            database->Open(false /* create_if_missing */));
+
+  // Should return true, indicating that the database could be created.
+  EXPECT_EQ(NotificationDatabase::STATUS_OK,
+            database->Open(true /* create_if_missing */));
+
+  EXPECT_TRUE(IsDatabaseOpen(database.get()));
+  EXPECT_FALSE(IsInMemoryDatabase(database.get()));
+
+  // Close the database, and re-open it without attempting to create it because
+  // the files on the file system should still exist as expected.
+  database.reset(CreateDatabaseOnFileSystem(database_dir.path()));
+  EXPECT_EQ(NotificationDatabase::STATUS_OK,
+            database->Open(false /* create_if_missing */));
+}
+
+TEST_F(NotificationDatabaseTest, DestroyDatabase) {
+  base::ScopedTempDir database_dir;
+  ASSERT_TRUE(database_dir.CreateUniqueTempDir());
+
+  scoped_ptr<NotificationDatabase> database(
+      CreateDatabaseOnFileSystem(database_dir.path()));
+
+  EXPECT_EQ(NotificationDatabase::STATUS_OK,
+            database->Open(true /* create_if_missing */));
+  EXPECT_TRUE(IsDatabaseOpen(database.get()));
+
+  // Destroy the database. This will immediately close it as well.
+  ASSERT_EQ(NotificationDatabase::STATUS_OK, database->Destroy());
+  EXPECT_FALSE(IsDatabaseOpen(database.get()));
+
+  // Try to re-open the database (but not re-create it). This should fail as
+  // the files associated with the database should have been blown away.
+  database.reset(CreateDatabaseOnFileSystem(database_dir.path()));
+  EXPECT_EQ(NotificationDatabase::STATUS_ERROR_NOT_FOUND,
+            database->Open(false /* create_if_missing */));
+}
+
+}  // namespace content