Use a two-part data format version in IndexedDB metadata.

content/browser/indexed_db/indexed_db_factory_unittest.cc

 // Copyright 2013 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 <stdint.h>
 #include <utility>
 
+#include "base/auto_reset.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/test_simple_task_runner.h"
 #include "content/browser/indexed_db/indexed_db_connection.h"
 #include "content/browser/indexed_db/indexed_db_context_impl.h"
+#include "content/browser/indexed_db/indexed_db_data_format_version.h"
 #include "content/browser/indexed_db/indexed_db_factory_impl.h"
 #include "content/browser/indexed_db/mock_indexed_db_callbacks.h"
 #include "content/browser/indexed_db/mock_indexed_db_database_callbacks.h"
 #include "content/browser/quota/mock_quota_manager_proxy.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/WebKit/public/platform/modules/indexeddb/WebIDBDatabaseException.h"
 #include "third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h"
 #include "url/gurl.h"
 #include "url/origin.h"
@@ skipping 34 matching lines @@
  private:
   ~MockIDBFactory() override {}
 
   DISALLOW_COPY_AND_ASSIGN(MockIDBFactory);
 };
 
 }  // namespace
 
 class IndexedDBFactoryTest : public testing::Test {
  public:
-  IndexedDBFactoryTest() {
+  void SetUp() override {
+    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
     task_runner_ = new base::TestSimpleTaskRunner();
     quota_manager_proxy_ = new MockQuotaManagerProxy(nullptr, nullptr);
     context_ = new IndexedDBContextImpl(
-        base::FilePath(), nullptr /* special_storage_policy */,
+        temp_dir_.GetPath(), nullptr /* special_storage_policy */,
         quota_manager_proxy_.get(), task_runner_.get());
     idb_factory_ = new MockIDBFactory(context_.get());
   }
-  ~IndexedDBFactoryTest() override {
+
+  void TearDown() override {
     quota_manager_proxy_->SimulateQuotaManagerDestroyed();
   }
 
  protected:
+  IndexedDBFactoryTest() {}
   MockIDBFactory* factory() const { return idb_factory_.get(); }
   void clear_factory() { idb_factory_ = nullptr; }
   IndexedDBContextImpl* context() const { return context_.get(); }
 
  private:
+  base::ScopedTempDir temp_dir_;
   scoped_refptr<base::TestSimpleTaskRunner> task_runner_;
   scoped_refptr<IndexedDBContextImpl> context_;
   scoped_refptr<MockIDBFactory> idb_factory_;
   scoped_refptr<MockQuotaManagerProxy> quota_manager_proxy_;
   TestBrowserThreadBundle thread_bundle_;
 
   DISALLOW_COPY_AND_ASSIGN(IndexedDBFactoryTest);
 };
 
 TEST_F(IndexedDBFactoryTest, BackingStoreLifetime) {
@@ skipping 404 matching lines @@
                     nullptr /* request_context */, origin,
                     temp_directory.GetPath());
     EXPECT_TRUE(callbacks->saw_error());
     EXPECT_FALSE(factory()->IsDatabaseOpen(origin, db_name));
   }
 
   // Terminate all pending-close timers.
   factory()->ForceClose(origin);
 }
 
+namespace {
+
+class DataLossCallbacks final : public MockIndexedDBCallbacks {
+ public:
+  blink::WebIDBDataLoss data_loss() const { return data_loss_; }
+  void OnSuccess(std::unique_ptr<IndexedDBConnection> connection,
+                 const IndexedDBDatabaseMetadata& metadata) override {
+    if (!connection_)
+      connection_ = std::move(connection);
+  }
+  void OnError(const IndexedDBDatabaseError& error) final {
+    ADD_FAILURE() << "Unexpected IDB error: " << error.message();
+  }
+  void OnUpgradeNeeded(int64_t old_version,
+                       std::unique_ptr<IndexedDBConnection> connection,
+                       const content::IndexedDBDatabaseMetadata& metadata,
+                       const IndexedDBDataLossInfo& data_loss) final {
+    connection_ = std::move(connection);
+    data_loss_ = data_loss.status;
+  }
+
+ private:
+  ~DataLossCallbacks() final {}
+  blink::WebIDBDataLoss data_loss_ = blink::WebIDBDataLossNone;
+};
+
+TEST_F(IndexedDBFactoryTest, DataFormatVersion) {
+  auto try_open = [this](const Origin& origin,
+                         const IndexedDBDataFormatVersion& version) {
+    base::AutoReset<IndexedDBDataFormatVersion> override_version(
+        &IndexedDBDataFormatVersion::GetMutableCurrentForTesting(), version);
+    auto db_callbacks = make_scoped_refptr(new MockIndexedDBDatabaseCallbacks);

[dcheng, 2017/04/07 06:36:04]

Another option is to call base::MakeShared

(Maybe we should have named this something different... meh)

[jbroman, 2017/04/07 14:27:50]

Ah, I missed that (didn't expect it to be called MakeShared given it's not
called shared_ptr).

Done.

+    auto callbacks = make_scoped_refptr(new DataLossCallbacks);
+    const int64_t transaction_id = 1;
+    factory()->Open(ASCIIToUTF16("test_db"),
+                    base::MakeUnique<IndexedDBPendingConnection>(
+                        callbacks, db_callbacks, 0 /* child_process_id */,
+                        transaction_id, 1 /* version */),
+                    nullptr /* request_context */, origin,
+                    context()->data_path());
+    base::RunLoop().RunUntilIdle();
+    auto* connection = callbacks->connection();
+    EXPECT_TRUE(connection);
+    connection->database()->Commit(connection->GetTransaction(transaction_id));
+    connection->Close();
+    factory()->ForceClose(origin);
+    return callbacks->data_loss();
+  };
+
+  using blink::WebIDBDataLossNone;
+  using blink::WebIDBDataLossTotal;
+  static const struct {
+    const char* origin;
+    IndexedDBDataFormatVersion open_version_1;
+    IndexedDBDataFormatVersion open_version_2;
+    blink::WebIDBDataLoss expected_data_loss;
+  } kTestCases[] = {
+      {"http://same-version.com/", {3, 4}, {3, 4}, WebIDBDataLossNone},
+      {"http://blink-upgrade.com/", {3, 4}, {3, 5}, WebIDBDataLossNone},
+      {"http://v8-upgrade.com/", {3, 4}, {4, 4}, WebIDBDataLossNone},
+      {"http://both-upgrade.com/", {3, 4}, {4, 5}, WebIDBDataLossNone},
+      {"http://blink-downgrade.com/", {3, 4}, {3, 3}, WebIDBDataLossTotal},
+      {"http://v8-downgrade.com/", {3, 4}, {2, 4}, WebIDBDataLossTotal},
+      {"http://both-downgrade.com/", {3, 4}, {2, 3}, WebIDBDataLossTotal},
+      {"http://v8-up-blink-down.com/", {3, 4}, {4, 2}, WebIDBDataLossTotal},
+      {"http://v8-down-blink-up.com/", {3, 4}, {2, 5}, WebIDBDataLossTotal},
+  };
+  for (const auto& test : kTestCases) {
+    SCOPED_TRACE(test.origin);
+    const Origin origin(GURL(test.origin));
+    ASSERT_EQ(WebIDBDataLossNone, try_open(origin, test.open_version_1));
+    EXPECT_EQ(test.expected_data_loss, try_open(origin, test.open_version_2));
+  }
+}
+
+}  // namespace
+
 }  // namespace content