Adding experimental JavaScript internationalization API to V8 as an extension...

src/extensions/experimental/i18n-extension.cc

Index: src/extensions/experimental/i18n-extension.cc
===================================================================
--- src/extensions/experimental/i18n-extension.cc	(revision 0)
+++ src/extensions/experimental/i18n-extension.cc	(revision 0)
@@ -0,0 +1,258 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "i18n-extension.h"
+
+#include <string>
+
+#include "unicode/locid.h"
+
+namespace v8 {
+namespace internal {
+
+I18NExtension* I18NExtension::extension_ = NULL;
+
+// TODO(cira): maybe move JS code to a .js file and generata cc files from it?
+const char* const I18NExtension::kSource =
+    "Locale = function(optLocale) {"
+    "    native function NativeJSLocale();"

[Mads Ager (chromium), 2010/12/09 00:36:13]

Please use two-space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+    "    var properties = NativeJSLocale(optLocale);"
+    "    this.locale = properties.locale;"
+    "    this.language = properties.language;"
+    "    this.script = properties.script;"
+    "    this.region = properties.region;"
+    "};"
+    "Locale.availableLocales = function() {"
+    "    native function NativeJSAvailableLocales();"
+    "    return NativeJSAvailableLocales();"
+    "};"
+    "Locale.prototype.maximizedLocale = function() {"
+    "    native function NativeJSMaximizedLocale();"
+    "    return new Locale(NativeJSMaximizedLocale(this.locale));"
+    "};"
+    "Locale.prototype.minimizedLocale = function() {"
+    "    native function NativeJSMinimizedLocale();"
+    "    return new Locale(NativeJSMinimizedLocale(this.locale));"
+    "};"
+    "Locale.prototype.displayLocale_ = function(displayLocale) {"
+    "    var result = this.locale;"
+    "    if (displayLocale !== undefined) {"
+    "        result = displayLocale.locale;"
+    "    }"
+    "    return result;"
+    "};"
+    "Locale.prototype.displayLanguage = function(optDisplayLocale) {"
+    "    var displayLocale = this.displayLocale_(optDisplayLocale);"
+    "    native function NativeJSDisplayLanguage();"
+    "    return NativeJSDisplayLanguage(this.locale, displayLocale);"
+    "};"
+    "Locale.prototype.displayScript = function(optDisplayLocale) {"
+    "    var displayLocale = this.displayLocale_(optDisplayLocale);"
+    "    native function NativeJSDisplayScript();"
+    "    return NativeJSDisplayScript(this.locale, displayLocale);"
+    "};"
+    "Locale.prototype.displayRegion = function(optDisplayLocale) {"
+    "    var displayLocale = this.displayLocale_(optDisplayLocale);"
+    "    native function NativeJSDisplayRegion();"
+    "    return NativeJSDisplayRegion(this.locale, displayLocale);"
+    "};"
+    "Locale.prototype.displayName = function(optDisplayLocale) {"
+    "    var displayLocale = this.displayLocale_(optDisplayLocale);"
+    "    native function NativeJSDisplayName();"
+    "    return NativeJSDisplayName(this.locale, displayLocale);"
+    "};";
+
+v8::Handle<v8::FunctionTemplate> I18NExtension::GetNativeFunction(
+    v8::Handle<v8::String> name) {
+  if (name->Equals(v8::String::New("NativeJSLocale"))) {
+    return v8::FunctionTemplate::New(JSLocale);
+  } else if (name->Equals(v8::String::New("NativeJSAvailableLocales"))) {
+    return v8::FunctionTemplate::New(JSAvailableLocales);
+  } else if (name->Equals(v8::String::New("NativeJSMaximizedLocale"))) {
+    return v8::FunctionTemplate::New(JSMaximizedLocale);
+  } else if (name->Equals(v8::String::New("NativeJSMinimizedLocale"))) {
+    return v8::FunctionTemplate::New(JSMinimizedLocale);
+  } else if (name->Equals(v8::String::New("NativeJSDisplayLanguage"))) {
+    return v8::FunctionTemplate::New(JSDisplayLanguage);
+  } else if (name->Equals(v8::String::New("NativeJSDisplayScript"))) {
+    return v8::FunctionTemplate::New(JSDisplayScript);
+  } else if (name->Equals(v8::String::New("NativeJSDisplayRegion"))) {
+    return v8::FunctionTemplate::New(JSDisplayRegion);
+  } else if (name->Equals(v8::String::New("NativeJSDisplayName"))) {
+    return v8::FunctionTemplate::New(JSDisplayName);
+  }
+
+  return v8::Handle<v8::FunctionTemplate>();
+}
+
+v8::Handle<v8::Value> I18NExtension::JSLocale(const v8::Arguments& args) {
+  // TODO(cira): Fetch browser locale. Accept en-US as good default for now.

[jungshik at Google, 2010/12/09 00:05:35]

Wonder what your plan is for this. Can the registration mechanism pass a param? 

[Nebojša Ćirić, 2010/12/09 00:57:13]

Added your comment to todo. Seems reasonable.

+  std::string locale_name("en-US");
+  if (args.Length() == 1 && args[0]->IsString()) {
+      locale_name = *v8::String::Utf8Value(args[0]->ToString());

[Mads Ager (chromium), 2010/12/09 00:36:13]

two-space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+  }
+
+  v8::Local<v8::Object> locale = v8::Object::New();
+  locale->Set(v8::String::New("locale"), v8::String::New(locale_name.c_str()));
+
+  icu::Locale icu_locale(locale_name.c_str());
+
+  const char* language = icu_locale.getLanguage();
+  locale->Set(v8::String::New("language"), v8::String::New(language));
+
+  const char* script = icu_locale.getScript();
+  if (strlen(script)) {
+    locale->Set(v8::String::New("script"), v8::String::New(script));
+  }
+
+  const char* region = icu_locale.getCountry();
+  if (strlen(region)) {
+    locale->Set(v8::String::New("region"), v8::String::New(region));
+  }
+
+  return locale;
+}
+
+// TODO(cira): Filter out locales that Chrome doesn't support.
+v8::Handle<v8::Value> I18NExtension::JSAvailableLocales(
+    const v8::Arguments& args) {
+  v8::Local<v8::Array> all_locales = v8::Array::New();
+
+  int count = 0;
+  const Locale* icu_locales = icu::Locale::getAvailableLocales(count);
+  for (int i = 0; i < count; ++i)
+      all_locales->Set(i, v8::String::New(icu_locales[i].getName()));

[Mads Ager (chromium), 2010/12/09 00:36:13]

two-space indent and braces around the body of the for-loop.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+
+  return all_locales;
+}
+
+// Use - as tag separator, not _ that ICU uses.
+static std::string NormalizeLocale(const std::string& locale) {
+  std::string result(locale);
+  std::replace(result.begin(), result.end(), '_', '-');

[jungshik at Google, 2010/12/09 00:05:35]

Wouldn't it be better (style-compliant) to include <algorithm> explicitly for
this? 

[Mads Ager (chromium), 2010/12/09 00:36:13]

This is fine for an experimental extension. If this makes it as a language
feature in all browsers and we want to make this a part of the V8 build we
should attempt to get rid of the STL part. However, this also needs ICU which is
probably a bigger issue for eventual integration. :)

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Ah joy :). Yes, this can be rewritten to not use STL. Added comment.

On 2010/12/09 00:36:13, Mads Ager wrote:

+  return result;
+}
+
+v8::Handle<v8::Value> I18NExtension::JSMaximizedLocale(
+    const v8::Arguments& args) {
+  if (!args.Length() || !args[0]->IsString()) {
+    return v8::Undefined();
+  }
+
+  UErrorCode status = U_ZERO_ERROR;
+  std::string locale_name = *v8::String::Utf8Value(args[0]->ToString());
+  char max_locale[ULOC_FULLNAME_CAPACITY];
+  uloc_addLikelySubtags(locale_name.c_str(), max_locale,

[jungshik at Google, 2010/12/09 00:05:35]

same here. For uloc_*, pls include <unicode/uloc.h> although it gets compiled
without that. 

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+                        sizeof(max_locale), &status);
+  if (U_FAILURE(status)) {
+      return v8::Undefined();

[Mads Ager (chromium), 2010/12/09 00:36:13]

two space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+  }
+
+  return v8::String::New(NormalizeLocale(max_locale).c_str());
+}
+
+v8::Handle<v8::Value> I18NExtension::JSMinimizedLocale(
+    const v8::Arguments& args) {
+  if (!args.Length() || !args[0]->IsString()) {
+      return v8::Undefined();

[Mads Ager (chromium), 2010/12/09 00:36:13]

two space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+  }
+
+  UErrorCode status = U_ZERO_ERROR;
+  std::string locale_name = *v8::String::Utf8Value(args[0]->ToString());
+  char min_locale[ULOC_FULLNAME_CAPACITY];
+  uloc_minimizeSubtags(locale_name.c_str(), min_locale,
+                       sizeof(min_locale), &status);
+  if (U_FAILURE(status)) {
+      return v8::Undefined();

[Mads Ager (chromium), 2010/12/09 00:36:13]

two space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+  }
+
+  return v8::String::New(NormalizeLocale(min_locale).c_str());
+}
+
+// Common code for JSDisplayXXX methods.
+static v8::Handle<v8::Value> GetDisplayItem(const v8::Arguments& args,
+                                            const std::string& item) {
+  if (args.Length() != 2 || !args[0]->IsString() || !args[1]->IsString()) {
+      return v8::Undefined();

[Mads Ager (chromium), 2010/12/09 00:36:13]

two space indent.

[Nebojša Ćirić, 2010/12/09 00:57:13]

Done.

+  }
+
+  std::string base_locale = *v8::String::Utf8Value(args[0]->ToString());
+  icu::Locale icu_locale(base_locale.c_str());
+  icu::Locale display_locale =
+      icu::Locale(*v8::String::Utf8Value(args[1]->ToString()));
+  UnicodeString result;
+  if (item == "language") {
+    icu_locale.getDisplayLanguage(display_locale, result);
+  } else if (item == "script") {
+    icu_locale.getDisplayScript(display_locale, result);
+  } else if (item == "region") {
+    icu_locale.getDisplayCountry(display_locale, result);
+  } else if (item == "name") {
+    icu_locale.getDisplayName(display_locale, result);
+  } else {
+    return v8::Undefined();
+  }
+
+  if (result.length()) {
+    return v8::String::New(
+        reinterpret_cast<const uint16_t*>(result.getBuffer()), result.length());
+  }
+
+  return v8::Undefined();
+}
+
+v8::Handle<v8::Value> I18NExtension::JSDisplayLanguage(
+    const v8::Arguments& args) {
+  return GetDisplayItem(args, "language");
+}
+
+v8::Handle<v8::Value> I18NExtension::JSDisplayScript(
+    const v8::Arguments& args) {
+  return GetDisplayItem(args, "script");
+}
+
+v8::Handle<v8::Value> I18NExtension::JSDisplayRegion(
+    const v8::Arguments& args) {
+  return GetDisplayItem(args, "region");
+}
+
+v8::Handle<v8::Value> I18NExtension::JSDisplayName(const v8::Arguments& args) {
+  return GetDisplayItem(args, "name");
+}
+
+I18NExtension* I18NExtension::get() {
+  if (!extension_) {
+    extension_ = new I18NExtension();
+  }
+  return extension_;
+}
+
+void I18NExtension::Register() {
+  static v8::DeclareExtension i18n_extension_declaration(I18NExtension::get());
+}
+
+} }  // namespace v8::internal