Implement an initial extension settings API.

chrome/browser/extensions/extension_settings_storage_unittest.cc

+// Copyright (c) 2011 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.
+
+// TODO(kalman): More tests:
+//  - Keys/values containing dots.
+//  - More than one active settings object.
+//  - Failure cases
+
+#include "chrome/browser/extensions/extension_settings_storage_unittest.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "base/json/json_writer.h"
+#include "base/values.h"
+#include "chrome/browser/extensions/extension_settings.h"
+
+// Define macros for these to get the __LINE__ expansion.
+// Undefined at the end of the file.
+#define newCallback(expected) \
+  (new AssertEqualsCallback((expected), false, __LINE__))
+#define newQuittingCallback(expected) \
+  (new AssertEqualsCallback((expected), true, __LINE__))
+
+namespace {
+
+// Wait for the QuitTask on the current message loop.  Converse of running a
+// storage function with a newQuittingCallback().
+void waitForQuit() {
+  MessageLoop::current()->Run();

[dgrogan, 2011/06/18 01:54:40]

When do you use Run vs RunAllPending?

[not at google - send to devlin, 2011/06/20 05:33:11]

I don't think RunAllPending would work, at least with the current flow, which is
 1. do something with storage
 2. wait until quit task
 ..... storage does stuff on FILE thread, responds on UI thread
 3. callback runs quit task
 4. resume
RunAllPending wouldn't block on (2) because there wouldn't be a pending task
until the FILE thread finishes its stuff.

Can you think of a cleaner way of doing it that wouldn't require the quit task
stuff?

[dgrogan, 2011/06/21 02:36:05]

Thanks for the good explanation.
The way I was just taught was to pass the current message loop to the file
BrowserThread but never start that thread.  Then your Tasks posted to the FILE
thread will queue on the current() message loop.  When you want to wait for them
to be executed you do MessageLoop::current()->RunAllPending();

The test I did that for is indexed_db_quota_client_unittest.cc:
http://codesearch.google.com/codesearch#OAMlx_jo-ck/src/content/browser/in_pr...

The long review:
http://codereview.chromium.org/7053030/#msg-ahJjaHJvbWl1bWNvZGVyZXZpZXdyHQsSB...

[not at google - send to devlin, 2011/06/22 09:40:38]

Ah, very nice.  Thank you.

+}
+
+// Callback from GetStorage() which places the new storage in a given location.
+// Posts a QuitTask to the current message loop when done.
+class GetStorageCallback : public ExtensionSettings::Callback {
+ public:
+  explicit GetStorageCallback(ExtensionSettingsStorage** storagePtr)
+      : storagePtr_(storagePtr) {
+    *storagePtr = NULL;
+  }
+
+  ~GetStorageCallback() {}
+
+  void Run(ExtensionSettingsStorage* storage) {
+    DCHECK(*storagePtr_ == NULL);
+    *storagePtr_ = storage;
+    MessageLoop::current()->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+  }
+
+ private:
+  ExtensionSettingsStorage** storagePtr_;
+};
+
+// Callback from storage methods which performs the test assertions.
+class AssertEqualsCallback : public ExtensionSettingsStorage::Callback {
+ public:
+  AssertEqualsCallback(DictionaryValue* expected, bool quit_when_done, int line)
+      : expected_(expected), quit_when_done_(quit_when_done), line_(line),
+        called_(false) {
+  }
+
+  ~AssertEqualsCallback() {
+    // Need to DCHECK since ASSERT_* can't be used from destructors.
+    DCHECK(called_);
+  }
+
+  void OnSuccess(DictionaryValue* actual) {
+    // Post quit task first so that it always runs even if the test fails.
+    MaybePostQuitTask();
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    ASSERT_FALSE(called_) << "Callback has already been called";
+    called_ = true;
+    ASSERT_TRUE(expected_->Equals(actual)) << "Values are different:\n" <<
+        "Line:     " << line_ << "\n" <<
+        "Expected: " << GetJson(expected_) <<
+        "Got:      " << GetJson(actual);
+    delete actual;
+  }
+
+  void OnFailure(const std::string& message) {
+    // Post quit task first so that it always runs even if the test fails.
+    MaybePostQuitTask();
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    ASSERT_FALSE(called_) << "Callback has already been called";
+    called_ = true;
+    // No tests allow failure (yet).
+    ASSERT_TRUE(false) << "Callback failed on line " << line_;
+  }
+
+ private:
+  std::string GetJson(Value* value) {
+    std::string json;
+    base::JSONWriter::Write(value, true, &json);
+    return json;
+  }
+
+  void MaybePostQuitTask() {
+    if (quit_when_done_) {
+      MessageLoop::current()->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+    }
+  }
+
+  DictionaryValue* expected_;
+  bool quit_when_done_;
+  int line_;
+  bool called_;
+};
+
+class TestSettingsCallback : public ExtensionSettings::Callback {
+ public:
+  explicit TestSettingsCallback(ExtensionSettingsStorage** storagePtr)
+      : storagePtr_(storagePtr) {
+    *storagePtr_ = NULL;
+  }
+
+  void Run(ExtensionSettingsStorage* storage) {
+    DCHECK(*storagePtr_ == NULL);
+    DCHECK(storage != NULL);
+    *storagePtr_ = storage;
+  }
+
+ private:
+  ExtensionSettingsStorage** storagePtr_;
+};
+
+std::string key1() {
+  return "foo";
+}
+
+std::string key2() {
+  return "bar";
+}
+
+std::string key3() {
+  return "baz";
+}
+
+Value* val1() {
+  Value* val = NULL;
+  if (val == NULL) {
+    val = Value::CreateStringValue(key1() + "Value");
+  }
+  return val;
+}
+
+Value* val2() {
+  static Value* val = NULL;
+  if (val == NULL) {
+    val = Value::CreateStringValue(key2() + "Value");
+  }
+  return val;
+}
+
+Value* val3() {
+  static Value* val = NULL;
+  if (val == NULL) {
+    val = Value::CreateStringValue(key3() + "Value");
+  }
+  return val;
+}
+
+ListValue* emptyList() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+  }
+  return val;
+}
+
+ListValue* list1() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+    val->Append(Value::CreateStringValue(key1()));
+  }
+  return val;
+}
+
+ListValue* list2() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+    val->Append(Value::CreateStringValue(key2()));
+  }
+  return val;
+}
+
+ListValue* list12() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+    val->Append(Value::CreateStringValue(key1()));
+    val->Append(Value::CreateStringValue(key2()));
+  }
+  return val;
+}
+
+ListValue* list13() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+    val->Append(Value::CreateStringValue(key1()));
+    val->Append(Value::CreateStringValue(key3()));
+  }
+  return val;
+}
+
+ListValue* list123() {
+  static ListValue* val = NULL;
+  if (val == NULL) {
+    val = new ListValue();
+    val->Append(Value::CreateStringValue(key1()));
+    val->Append(Value::CreateStringValue(key2()));
+    val->Append(Value::CreateStringValue(key3()));
+  }
+  return val;
+}
+
+DictionaryValue* emptyDict() {
+  static DictionaryValue* val = NULL;
+  if (val == NULL) {
+    val = new DictionaryValue();
+  }
+  return val;
+}
+
+DictionaryValue* dict1() {
+  static DictionaryValue* val = NULL;
+  if (val == NULL) {
+    val = new DictionaryValue();
+    val->Set(key1(), val1()->DeepCopy());
+  }
+  return val;
+}
+
+DictionaryValue* dict12() {
+  static DictionaryValue* val = NULL;
+  if (val == NULL) {
+    val = new DictionaryValue();
+    val->Set(key1(), val1()->DeepCopy());
+    val->Set(key2(), val2()->DeepCopy());
+  }
+  return val;
+}
+
+DictionaryValue* dict123() {
+  static DictionaryValue* val = NULL;
+  if (val == NULL) {
+    val = new DictionaryValue();
+    val->Set(key1(), val1()->DeepCopy());
+    val->Set(key2(), val2()->DeepCopy());
+    val->Set(key3(), val3()->DeepCopy());
+  }
+  return val;
+}
+
+}  // namespace
+
+void ExtensionSettingsStorageTest::SetUp() {
+  ui_message_loop_ = new MessageLoopForUI();
+  ui_thread_ = new BrowserThread(BrowserThread::UI, MessageLoop::current());
+  file_thread_ = new BrowserThread(BrowserThread::FILE);
+  file_thread_->Start();
+
+  FilePath temp_dir;
+  file_util::CreateNewTempDirectory("", &temp_dir);
+  settings_ = new ExtensionSettings(temp_dir);
+
+  storage_ = NULL;
+  settings_->GetStorageForTesting(GetParam(), "fakeExtension",
+      new GetStorageCallback(&storage_));
+  waitForQuit();
+  DCHECK(storage_ != NULL);
+}
+
+void ExtensionSettingsStorageTest::TearDown() {
+  delete settings_;
+
+  file_thread_->Stop();
+  delete file_thread_;
+  delete ui_thread_;
+  delete ui_message_loop_;
+}
+
+TEST_P(ExtensionSettingsStorageTest, GetWhenEmpty) {
+  storage_->Get(key1(), newCallback(emptyDict()));
+  storage_->Get(key2(), newCallback(emptyDict()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(emptyDict()));
+  storage_->Get(*list123(), newCallback(emptyDict()));
+
+  storage_->Get(newQuittingCallback(emptyDict()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, GetWithSingleValue) {
+  storage_->Set(key1(), *val1(), newQuittingCallback(dict1()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(dict1()));
+  storage_->Get(key2(), newCallback(emptyDict()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(dict1()));
+  storage_->Get(*list2(), newCallback(emptyDict()));
+  storage_->Get(*list123(), newCallback(dict1()));
+
+  storage_->Get(newQuittingCallback(dict1()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, GetWithMultipleValues) {
+  storage_->Set(*dict12(), newQuittingCallback(dict12()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(dict1()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(dict1()));
+  storage_->Get(*list13(), newCallback(dict1()));
+  storage_->Get(*list12(), newCallback(dict12()));
+  storage_->Get(*list123(), newCallback(dict12()));
+
+  storage_->Get(newQuittingCallback(dict12()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, RemoveWhenEmpty) {
+  storage_->Remove(key1(), newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(emptyDict()));
+
+  storage_->Get(newQuittingCallback(emptyDict()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, RemoveWithSingleValue) {
+  storage_->Set(key1(), *val1(), newQuittingCallback(dict1()));
+  waitForQuit();
+  storage_->Remove(key1(), newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(emptyDict()));
+  storage_->Get(key2(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(emptyDict()));
+  storage_->Get(*list12(), newCallback(emptyDict()));
+
+  storage_->Get(newQuittingCallback(emptyDict()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, RemoveWithMultipleValues) {
+  storage_->Set(*dict123(), newQuittingCallback(dict123()));
+  waitForQuit();
+  storage_->Remove(key3(), newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(dict1()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(dict1()));
+  storage_->Get(*list13(), newCallback(dict1()));
+  storage_->Get(*list12(), newCallback(dict12()));
+  storage_->Get(*list123(), newCallback(dict12()));
+  storage_->Get(newCallback(dict12()));
+
+  storage_->Remove(*list2(), newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(dict1()));
+  storage_->Get(key2(), newCallback(emptyDict()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(dict1()));
+  storage_->Get(*list2(), newCallback(emptyDict()));
+  storage_->Get(*list123(), newCallback(dict1()));
+
+  storage_->Get(newQuittingCallback(dict1()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, SetWhenOverwriting) {
+  DictionaryValue key1Val2;
+  key1Val2.Set(key1(), val2()->DeepCopy());
+  storage_->Set(key1(), *val2(), newQuittingCallback(&key1Val2));
+  waitForQuit();
+
+  storage_->Set(*dict12(), newQuittingCallback(dict12()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(dict1()));
+  storage_->Get(key3(), newCallback(emptyDict()));
+  storage_->Get(*emptyList(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(dict1()));
+  storage_->Get(*list13(), newCallback(dict1()));
+  storage_->Get(*list12(), newCallback(dict12()));
+  storage_->Get(*list123(), newCallback(dict12()));
+
+  storage_->Get(newQuittingCallback(dict12()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, ClearWhenEmpty) {
+  storage_->Clear(newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(emptyDict()));
+
+  storage_->Get(newQuittingCallback(emptyDict()));
+  waitForQuit();
+}
+
+TEST_P(ExtensionSettingsStorageTest, ClearWhenNotEmpty) {
+  storage_->Set(*dict12(), newQuittingCallback(dict12()));
+  waitForQuit();
+  storage_->Clear(newQuittingCallback(emptyDict()));
+  waitForQuit();
+
+  storage_->Get(key1(), newCallback(emptyDict()));
+  storage_->Get(*list1(), newCallback(emptyDict()));
+
+  storage_->Get(newQuittingCallback(emptyDict()));
+  waitForQuit();
+}
+
+#undef newCallback
+#undef newQuittingCallback