Adding break iterator support to the i18n api extension....

src/extensions/experimental/break-iterator.cc

+// Copyright 2011 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 "break-iterator.h"
+
+#include "unicode/brkiter.h"
+#include "unicode/locid.h"
+#include "unicode/rbbi.h"
+
+namespace v8 {
+namespace internal {
+
+v8::Persistent<v8::FunctionTemplate> BreakIterator::break_iterator_template_;
+
+icu::BreakIterator* BreakIterator::UnpackBreakIterator(
+    v8::Handle<v8::Object> obj) {
+  if (break_iterator_template_->HasInstance(obj)) {
+    return static_cast<icu::BreakIterator*>(
+        obj->GetPointerFromInternalField(0));
+  }
+
+  return NULL;
+}
+
+void BreakIterator::DeleteBreakIterator(v8::Persistent<v8::Value> object,
+                                        void* param) {
+  v8::Persistent<v8::Object> persistent_object =
+      v8::Persistent<v8::Object>::Cast(object);
+
+  // First delete the hidden C++ object. Deleting NULL is ok.

[Mads Ager (chromium), 2011/03/01 18:58:32]

Unpacking should never give NULL here. That will only happen if you use this as
the weak callback for persistent handles not pointing to a break iterator. Maybe
update the comment with that info instead?

[Nebojša Ćirić, 2011/03/01 19:09:12]

Done.

+  delete UnpackBreakIterator(persistent_object);
+
+  // Then dispose of the persistent handle to JS object.
+  persistent_object.Dispose();
+}
+
+// Returns a ThrowException value in case we encounter invalid

[Mads Ager (chromium), 2011/03/01 18:58:32]

ThrowException returns undefined and schedules an exception to be thrown (which
means that the undefined is ignored and the stack unwinded). Change the comment:
"Returns a ThrowEception value" -> "Throws an exception"?

[Nebojša Ćirić, 2011/03/01 19:09:12]

Done.

+// object in UnpackBreakIterator method.
+static v8::Handle<v8::Value> ThrowUnexpectedObjectError() {
+  return v8::ThrowException(v8::Exception::Error(
+      v8::String::New("BreakIterator method called on an object "
+                      "that is not a BreakIterator.")));
+}
+
+v8::Handle<v8::Value> BreakIterator::BreakIteratorAdoptText(
+    const v8::Arguments& args) {
+  if (args.Length() != 1 || !args[0]->IsString()) {
+    return v8::ThrowException(v8::Exception::SyntaxError(
+        v8::String::New("Text input is required.")));
+  }
+
+  icu::BreakIterator* break_iterator = UnpackBreakIterator(args.Holder());
+  if (!break_iterator) {
+    return ThrowUnexpectedObjectError();
+  }
+
+  v8::Local<v8::String> text_value = args[0]->ToString();
+  UnicodeString text(*v8::String::Value(text_value),
+                     text_value->Length());
+
+  break_iterator->setText(text);
+
+  return v8::Undefined();
+}
+
+v8::Handle<v8::Value> BreakIterator::BreakIteratorFirst(
+    const v8::Arguments& args) {
+  icu::BreakIterator* break_iterator = UnpackBreakIterator(args.Holder());
+  if (!break_iterator) {
+    return ThrowUnexpectedObjectError();
+  }
+
+  return v8::Int32::New(break_iterator->first());
+}
+
+v8::Handle<v8::Value> BreakIterator::BreakIteratorNext(
+    const v8::Arguments& args) {
+  icu::BreakIterator* break_iterator = UnpackBreakIterator(args.Holder());
+  if (!break_iterator) {
+    return ThrowUnexpectedObjectError();
+  }
+
+  return v8::Int32::New(break_iterator->next());
+}
+
+v8::Handle<v8::Value> BreakIterator::BreakIteratorCurrent(
+    const v8::Arguments& args) {
+  icu::BreakIterator* break_iterator = UnpackBreakIterator(args.Holder());
+  if (!break_iterator) {
+    return ThrowUnexpectedObjectError();
+  }
+
+  return v8::Int32::New(break_iterator->current());
+}
+
+v8::Handle<v8::Value> BreakIterator::BreakIteratorBreakType(
+    const v8::Arguments& args) {
+  icu::BreakIterator* break_iterator = UnpackBreakIterator(args.Holder());
+  if (!break_iterator) {
+    return ThrowUnexpectedObjectError();
+  }
+
+  // TODO(cira): Remove cast once ICU fixes base BreakIterator class.
+  int32_t status =
+      static_cast<RuleBasedBreakIterator*>(break_iterator)->getRuleStatus();
+  // Keep return values in sync with JavaScript BreakType enum.
+  if (status >= UBRK_WORD_NONE && status < UBRK_WORD_NONE_LIMIT) {
+    return v8::Int32::New(UBRK_WORD_NONE);
+  } else if (status >= UBRK_WORD_NUMBER && status < UBRK_WORD_NUMBER_LIMIT) {
+    return v8::Int32::New(UBRK_WORD_NUMBER);
+  } else if (status >= UBRK_WORD_LETTER && status < UBRK_WORD_LETTER_LIMIT) {
+    return v8::Int32::New(UBRK_WORD_LETTER);
+  } else if (status >= UBRK_WORD_KANA && status < UBRK_WORD_KANA_LIMIT) {
+    return v8::Int32::New(UBRK_WORD_KANA);
+  } else if (status >= UBRK_WORD_IDEO && status < UBRK_WORD_IDEO_LIMIT) {
+    return v8::Int32::New(UBRK_WORD_IDEO);
+  } else {
+    return v8::Int32::New(-1);
+  }
+}
+
+v8::Handle<v8::Value> BreakIterator::JSBreakIterator(
+    const v8::Arguments& args) {
+  v8::HandleScope handle_scope;
+
+  if (args.Length() != 2 || !args[0]->IsString() || !args[1]->IsString()) {
+    return v8::ThrowException(v8::Exception::SyntaxError(
+        v8::String::New("Locale and iterator type are required.")));
+  }
+
+  const char* locale = *v8::String::Utf8Value(args[0]->ToString());
+  icu::Locale icu_locale(locale);
+
+  UErrorCode status = U_ZERO_ERROR;
+  icu::BreakIterator* break_iterator = NULL;
+  const char* type = *v8::String::Utf8Value(args[1]->ToString());
+  if (!strcmp(type, "character")) {
+    break_iterator =
+        icu::BreakIterator::createCharacterInstance(icu_locale, status);
+  } else if (!strcmp(type, "word")) {
+    break_iterator =
+        icu::BreakIterator::createWordInstance(icu_locale, status);
+  } else if (!strcmp(type, "sentence")) {
+    break_iterator =
+        icu::BreakIterator::createSentenceInstance(icu_locale, status);
+  } else if (!strcmp(type, "line")) {
+    break_iterator =
+        icu::BreakIterator::createLineInstance(icu_locale, status);
+  } else {
+    return v8::ThrowException(v8::Exception::SyntaxError(
+        v8::String::New("Invalid iterator type.")));
+  }
+
+  if (U_FAILURE(status)) {
+    delete break_iterator;
+    return v8::ThrowException(v8::Exception::Error(
+        v8::String::New("Failed to create break iterator.")));
+  }
+
+  if (break_iterator_template_.IsEmpty()) {
+    v8::Local<v8::FunctionTemplate> raw_template(v8::FunctionTemplate::New());
+
+    raw_template->SetClassName(v8::String::New("v8Locale.v8BreakIterator"));
+
+    // Define internal field count on instance template.
+    v8::Local<v8::ObjectTemplate> object_template =
+        raw_template->InstanceTemplate();
+    object_template->SetInternalFieldCount(1);
+
+    // Define all of the prototype methods on prototype template.
+    v8::Local<v8::ObjectTemplate> proto = raw_template->PrototypeTemplate();
+    proto->Set(v8::String::New("adoptText"),
+               v8::FunctionTemplate::New(BreakIteratorAdoptText));
+    proto->Set(v8::String::New("first"),
+               v8::FunctionTemplate::New(BreakIteratorFirst));
+    proto->Set(v8::String::New("next"),
+               v8::FunctionTemplate::New(BreakIteratorNext));
+    proto->Set(v8::String::New("current"),
+               v8::FunctionTemplate::New(BreakIteratorCurrent));
+    proto->Set(v8::String::New("breakType"),
+               v8::FunctionTemplate::New(BreakIteratorBreakType));
+
+    break_iterator_template_ =
+        v8::Persistent<v8::FunctionTemplate>::New(raw_template);
+  }
+
+  // Create an empty object wrapper.
+  v8::Local<v8::Object> local_object =
+      break_iterator_template_->GetFunction()->NewInstance();
+  v8::Persistent<v8::Object> wrapper =
+      v8::Persistent<v8::Object>::New(local_object);
+
+  // Set break iterator as internal field of the resulting JS object.
+  wrapper->SetPointerInInternalField(0, break_iterator);
+
+  // Make object handle weak so we can delete iterator once GC kicks in.
+  wrapper.MakeWeak(NULL, DeleteBreakIterator);
+
+  return wrapper;
+}
+
+} }  // namespace v8::internal