Added chrome.i18n extension API.

The API proposal doc is 
http://sites.google.com/a/chromium.org/dev/developers/design-documents/extensions/i18n-api

This CL only adds the getter of accept languages: 
chrome.i18n.getAcceptLanguages().

The setter of accept languages will be added in a separate CL.

BUG=http://crbug.com/14574
TEST=TEST=There is an extension in chrome\test\data\extensions\samples\i18n.
Load this extension. It creates a toolstrip button.  Click this button, you
should get chrome's accept languages.
Review URL: http://codereview.chromium.org/174116

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@25810 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/extensions/extension_function_dispatcher.cc

@@ -10,6 +10,7 @@
 #include "chrome/browser/extensions/extension_bookmarks_module.h"
 #include "chrome/browser/extensions/extension_bookmarks_module_constants.h"
 #include "chrome/browser/extensions/extension_function.h"
+#include "chrome/browser/extensions/extension_i18n_api.h"
 #include "chrome/browser/extensions/extension_message_service.h"
 #include "chrome/browser/extensions/extension_page_actions_module.h"
 #include "chrome/browser/extensions/extension_page_actions_module_constants.h"
@@ -69,6 +70,7 @@ void FactoryRegistry::ResetFunctions() {
   // Register all functions here.
 
   namespace bookmarks = extension_bookmarks_module_constants;
+  namespace i18n = extension_i18n_api_functions;
   namespace page_actions = extension_page_actions_module_constants;
   namespace tabs = extension_tabs_module_constants;
   namespace test = extension_test_api_functions;
@@ -142,6 +144,10 @@ void FactoryRegistry::ResetFunctions() {
   factories_[toolstrip::kCollapseFunction] =
       &NewExtensionFunction<ToolstripCollapseFunction>;
 
+  // I18N.
+  factories_[i18n::kGetAcceptLanguagesFunction] =
+      &NewExtensionFunction<GetAcceptLanguagesFunction>;
+
   // Test.
   factories_[test::kPassFunction] =
       &NewExtensionFunction<ExtensionTestPassFunction>;

chrome/browser/extensions/extension_i18n_api.cc

+// Copyright (c) 2009 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 "chrome/browser/extensions/extension_i18n_api.h"
+
+#include "chrome/browser/profile.h"
+#include "chrome/common/pref_names.h"
+
+namespace extension_i18n_api_functions {
+  const char kGetAcceptLanguagesFunction[] = "i18n.getAcceptLanguages";
+}  // namespace extension_i18n_api_functions
+
+namespace {
+  // Errors.
+  const char kEmptyAcceptLanguagesError[] = "accept-languages is empty.";
+}  // namespace
+
+bool GetAcceptLanguagesFunction::RunImpl() {
+  std::wstring acceptLanguages =
+      profile()->GetPrefs()->GetString(prefs::kAcceptLanguages);
+  // Currently, there are 2 ways to set browser's accept-languages: through UI
+  // or directly modify the preference file. The accept-languages set through
+  // UI is guranteed to be valid, and the accept-languages string returned from
+  // profile()->GetPrefs()->GetString(prefs::kAcceptLanguages) is guranteed to
+  // be valid and well-formed, which means each accept-langauge is a valid
+  // code, and accept-languages are seperatd by "," without surrrounding
+  // spaces. But we do not do any validation (either the format or the validity
+  // of the language code) on accept-languages set through editing preference
+  // file directly. So, here, we're adding extra checks to be resistant to
+  // crashes caused by data corruption.
+  result_.reset(new ListValue());
+  if (acceptLanguages.empty()) {
+    error_ = kEmptyAcceptLanguagesError;
+    return false;
+  }
+  size_t begin = 0;
+  size_t end;
+  std::wstring acceptLang;
+  while (1) {
+    end = acceptLanguages.find(',', begin);
+    if (end > begin) {
+      // Guard against a malformed value with multiple "," in a row.
+      acceptLang = acceptLanguages.substr(begin, end - begin);
+      static_cast<ListValue*>(result_.get())->
+          Append(Value::CreateStringValue(acceptLang));
+    }
+    begin = end + 1;
+    // 'begin >= acceptLanguages.length()' to guard against a value
+    // ending with ','.
+    if (end == std::wstring::npos || begin >= acceptLanguages.length())
+      break;
+  }
+  if (static_cast<ListValue*>(result_.get())->GetSize() == 0) {
+    error_ = kEmptyAcceptLanguagesError;
+    return false;
+  }
+  return true;
+}

chrome/browser/extensions/extension_i18n_api.h

+// Copyright (c) 2009 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.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_I18N_API_H__
+#define CHROME_BROWSER_EXTENSIONS_EXTENSION_I18N_API_H__
+
+#include "chrome/browser/extensions/extension_function.h"
+
+namespace extension_i18n_api_functions {
+  extern const char kGetAcceptLanguagesFunction[];
+};  // namespace extension_i18n_api_functions
+
+class GetAcceptLanguagesFunction : public SyncExtensionFunction {
+  virtual bool RunImpl();
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_I18N_API_H__

chrome/browser/extensions/extension_i18n_apitest.cc

+// Copyright (c) 2009 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 "chrome/browser/extensions/extension_apitest.h"
+
+IN_PROC_BROWSER_TEST_F(ExtensionApiTest, I18N) {
+  ASSERT_TRUE(RunExtensionTest("i18n")) << message_;
+}

chrome/chrome.gyp

@@ -75,6 +75,7 @@
       'browser/extensions/extension_startup_unittest.cc',
       'browser/extensions/extension_storage_apitest.cc',
       'browser/extensions/extension_tabs_apitest.cc',
+      'browser/extensions/extension_i18n_apitest.cc',
       'browser/views/browser_views_accessibility_browsertest.cc',
       'browser/views/find_bar_win_browsertest.cc',
       # TODO(jam): http://crbug.com/15101 These tests fail on Linux and Mac.
@@ -1140,6 +1141,8 @@
         'browser/extensions/extension_message_service.h',
         'browser/extensions/extension_browser_event_router.cc',
         'browser/extensions/extension_browser_event_router.h',
+        'browser/extensions/extension_i18n_api.cc',
+        'browser/extensions/extension_i18n_api.h',
         'browser/extensions/extension_page_actions_module.cc',
         'browser/extensions/extension_page_actions_module.h',
         'browser/extensions/extension_page_actions_module_constants.cc',

chrome/common/common_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This comment is only here because changes to resources are not picked up
-without changes to the corresponding grd file. rw2 -->
+without changes to the corresponding grd file. xji -->
 <grit latest_public_release="0" current_release="1">
   <outputs>
     <output filename="grit/common_resources.h" type="rc_header">

chrome/common/extensions/api/extension_api.json

@@ -1018,6 +1018,28 @@
     ],
     "events": []
   },
+  {
+    "namespace": "i18n",
+    "types": [],
+    "functions": [
+      {
+        "name": "getAcceptLanguages",
+        "type": "function",
+        "description": "Get accept languages of browser",
+        "parameters": [
+          {
+            "type": "function",
+            "name": "callback",
+            "parameters": [
+              {"name": "languages", "type": "array", "items": {"type": "string"}, "description": "Array of the accept languages of the browser, such as en-US,en,zh-CN"}
+            ]
+          }
+        ]
+      }
+    ],
+    "events": [
+    ]
+  },
   {
     "namespace": "devtools",
     "types": [

chrome/renderer/extensions/extension_api_client_unittest.cc

@@ -588,3 +588,19 @@ TEST_F(ExtensionAPIClientTest, CollapseToolstrip) {
                "Uncaught Error: Invalid value for argument 1. "
                "Expected 'function' but got 'integer'.");
 }
+
+// I18N API
+TEST_F(ExtensionAPIClientTest, GetAcceptLanguages) {
+  ExpectJsFail("chrome.i18n.getAcceptLanguages(32, function(){})",
+               "Uncaught Error: Too many arguments.");
+
+  ExpectJsFail("chrome.i18n.getAcceptLanguages()",
+               "Uncaught Error: Parameter 0 is required.");
+
+  ExpectJsFail("chrome.i18n.getAcceptLanguages('abc')",
+               "Uncaught Error: Invalid value for argument 0. "
+               "Expected 'function' but got 'string'.");
+
+  ExpectJsPass("chrome.i18n.getAcceptLanguages(function(){})",
+               "i18n.getAcceptLanguages", "null");
+}

chrome/test/data/extensions/api_test/i18n/manifest.json

+{
+  "name": "chrome.i18n",
+  "version": "0.1",
+  "description": "end-to-end browser test for chrome.i18n API",
+  "background_page": "test.html"
+}

chrome/test/data/extensions/api_test/i18n/test.html

+<script src="test.js"></script>

chrome/test/data/extensions/api_test/i18n/test.js

+// i18n api test
+// browser_tests.exe --gtest_filter=ExtensionApiTest.I18N
+
+var testCallback = chrome.test.testCallback;
+
+chrome.test.runTests([
+  function getAcceptLanguages() {
+    chrome.i18n.getAcceptLanguages(chrome.test.callbackPass(function(results) {
+      chrome.test.assertEq(results.length, 2);
+      chrome.test.assertEq(results[0], "en-US");
+      chrome.test.assertEq(results[1], "en");
+    }));
+  }
+]);

chrome/test/data/extensions/samples/i18n/manifest.json

+{
+  "name": "AcceptLanguage",
+  "description": "Returns accept languages of the browser",
+  "version": "0.1",
+  "toolstrips": ["toolstrip.html"]
+}

chrome/test/data/extensions/samples/i18n/toolstrip.html

+<!--
+Copyright (c) 2009 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.
+-->
+
+<html>
+  <head>
+    <script>
+      function getAcceptLanguages() {
+        chrome.i18n.getAcceptLanguages(function(languageList) {
+          var languages = "";
+          for (var i = 0; i < languageList.length; i++) {
+            if (i == languageList.length - 1)
+              languages += languageList[i];
+            else
+              languages += languageList[i] + ",";
+          }
+          document.getElementById("languageSpan").innerHTML = languages;
+        })
+      }
+    </script>
+  </head>
+  <body>
+    <div class="toolstrip-button" onclick="getAcceptLanguages();">
+    <span id="languageSpan">GetAcceptLanguage</span>
+    </div>
+  </body>
+</html>