Modularize Compact Language Detector 2 (CLD2) data sources

chrome/browser/translate/scoped_cld_standalone_data_harness.cc

+// Copyright 2014 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 "scoped_cld_standalone_data_harness.h"
+
+#include "base/base_paths.h"
+#include "base/file_util.h"
+#include "base/logging.h"
+#include "base/path_service.h"
+#include "chrome/common/chrome_paths.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+
+namespace {
+
+// This comes from chrome_translate_client.cc
+const base::FilePath::CharType kStandaloneDataFileName[] =
+    FILE_PATH_LITERAL("cld2_data.bin");
+
+}  // namespace
+
+namespace test {
+
+ScopedCldStandaloneDataHarness::ScopedCldStandaloneDataHarness() {
+  // Constructor does nothing in all cases. See Init() for initialization.
+}
+
+ScopedCldStandaloneDataHarness::~ScopedCldStandaloneDataHarness() {
+  VLOG(1) << "Tearing down CLD data harness";
+  DeleteStandaloneDataFile();
+}
+
+void ScopedCldStandaloneDataHarness::Init() {
+  VLOG(1) << "Initializing CLD data harness";
+  // Dynamic data mode is enabled and we are using a standalone file.
+  ASSERT_NO_FATAL_FAILURE(CopyStandaloneDataFile());
+}
+
+void ScopedCldStandaloneDataHarness::GetStandaloneDataFileSource(
+    base::FilePath* out_path) {
+  ScopedCldDataHarness::GetTestDataSourceDirectory(out_path);
+  *out_path = out_path->Append(FILE_PATH_LITERAL("_platform_specific"))
+      .Append(FILE_PATH_LITERAL("all"))
+      .Append(kStandaloneDataFileName);
+}
+
+// Using the USER_DATA_DIR not only mimics true functionality, but also is
+// important to test isolation. Each test gets its own USER_DATA_DIR, which
+// ensures proper isolation between test processes running in parallel.
+void ScopedCldStandaloneDataHarness::GetStandaloneDataFileDestination(
+    base::FilePath* out_path) {
+  ASSERT_TRUE(PathService::Get(chrome::DIR_USER_DATA, out_path));
+  *out_path = out_path->Append(kStandaloneDataFileName);
+}
+
+void ScopedCldStandaloneDataHarness::DeleteStandaloneDataFile() {
+  base::FilePath path;
+  ASSERT_NO_FATAL_FAILURE(GetStandaloneDataFileDestination(&path));
+  VLOG(1) << "Deleting CLD test data file from " << path.value();
+  base::DeleteFile(path, false);
+}
+
+void ScopedCldStandaloneDataHarness::CopyStandaloneDataFile() {
+  DeleteStandaloneDataFile();  // sanity: blow away any old copies.
+  base::FilePath target_file;
+  GetStandaloneDataFileDestination(&target_file);
+  base::FilePath target_dir = target_file.DirName();
+  ASSERT_TRUE(base::CreateDirectoryAndGetError(target_dir, NULL));
+  base::FilePath source_file;
+  GetStandaloneDataFileSource(&source_file);
+  VLOG(1) << "Copying CLD test data file from " << source_file.value()
+             << " to " << target_file.value();
+  ASSERT_TRUE(base::CopyFile(source_file, target_file));
+  ASSERT_TRUE(base::PathExists(target_file));
+}
+
+scoped_ptr<ScopedCldDataHarness>
+  CreateScopedCldDataHarness() {
+  scoped_ptr<ScopedCldDataHarness> result(new ScopedCldStandaloneDataHarness());
+  return result.Pass();
+}
+
+}  // namespace test