Use ICU case conversion/transliterator for case conversion behind a flag

src/js/i18n.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // ECMAScript 402 API implementation.
 
 /**
  * Intl object is a single object that has some named properties,
  * all of which are constructors.
  */
@@ skipping 126 matching lines @@
   'numberformat': UNDEFINED,
   'dateformat': UNDEFINED,
   'breakiterator': UNDEFINED
 };
 
 /**
  * Caches default ICU locale.
  */
 var DEFAULT_ICU_LOCALE = UNDEFINED;
 
+function GetDefaultICULocaleJS() {
+  if (IS_UNDEFINED(DEFAULT_ICU_LOCALE)) {
+    DEFAULT_ICU_LOCALE = %GetDefaultICULocale();
+  }
+  return DEFAULT_ICU_LOCALE;
+}
+
 /**
  * Unicode extension regular expression.
  */
 var UNICODE_EXTENSION_RE = UNDEFINED;
 
 function GetUnicodeExtensionRE() {
   if (IS_UNDEFINED(UNDEFINED)) {
     UNICODE_EXTENSION_RE = new GlobalRegExp('-u(-[a-z0-9]{2,8})+', 'g');
   }
   return UNICODE_EXTENSION_RE;
@@ skipping 284 matching lines @@
       // Truncate locale if possible.
       var pos = %_Call(StringLastIndexOf, locale, '-');
       if (pos === -1) {
         break;
       }
       locale = %_Call(StringSubstring, locale, 0, pos);
     } while (true);
   }
 
   // Didn't find a match, return default.
-  if (IS_UNDEFINED(DEFAULT_ICU_LOCALE)) {
-    DEFAULT_ICU_LOCALE = %GetDefaultICULocale();
-  }
-
-  return {'locale': DEFAULT_ICU_LOCALE, 'extension': '', 'position': -1};
+  return {'locale': GetDefaultICULocaleJS(), 'extension': '', 'position': -1};
 }
 
 
 /**
  * Returns best matched supported locale and extension info using
  * implementation dependend algorithm.
  */
 function bestFitMatcher(service, requestedLocales) {
   // TODO(cira): implement better best fit algorithm.
   return lookupMatcher(service, requestedLocales);
@@ skipping 1519 matching lines @@
   var useOptions = (IS_UNDEFINED(defaults)) ? options : defaults;
   if (IS_UNDEFINED(locales) && IS_UNDEFINED(options)) {
     if (IS_UNDEFINED(defaultObjects[service])) {
       defaultObjects[service] = new savedObjects[service](locales, useOptions);
     }
     return defaultObjects[service];
   }
   return new savedObjects[service](locales, useOptions);
 }
 
+function getCaseConversionLanguageId(locales) {
+  var locales = initializeLocaleList(locales);
+  var language = locales.length > 0 ? locales[0] : GetDefaultICULocaleJS();
+  var pos = %_Call(StringIndexOf, language, '-');
+  if (pos != -1)
+    language = %_Call(StringSubstring, language, 0, pos);
+  var CUSTOM_CASE_LANGUAGES = ['az', 'el', 'lt', 'tr'];
+  return %_Call(ArrayIndexOf, CUSTOM_CASE_LANGUAGES, language);
+}
+
+function localeConvertCase(s, locales, isToUpper) {
+  var caseConversionLanguageId = getCaseConversionLanguageId(locales);
+  if (caseConversionLanguageId == -1)
+    return isToUpper ? %StringToUpperCaseI18N(s) : %StringToLowerCaseI18N(s);
+  return %StringLocaleConvertCase(s, isToUpper, caseConversionLanguageId);
+}
+
 /**
  * Compares this and that, and returns less than 0, 0 or greater than 0 value.
  * Overrides the built-in method.
  */
 OverrideFunction(GlobalString.prototype, 'localeCompare', function(that) {
     if (!IS_UNDEFINED(new.target)) {
       throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
     }
 
     if (IS_NULL_OR_UNDEFINED(this)) {
@@ skipping 32 matching lines @@
     var normalizationForm = %_Call(ArrayIndexOf, NORMALIZATION_FORMS, form);
     if (normalizationForm === -1) {
       throw MakeRangeError(kNormalizationForm,
           %_Call(ArrayJoin, NORMALIZATION_FORMS, ', '));
     }
 
     return %StringNormalize(s, normalizationForm);
   }
 );
 
+OverrideFunction(GlobalString.prototype, 'toLowerCase', function() {
+    if (!IS_UNDEFINED(new.target)) {
+      throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
+    }
+    CHECK_OBJECT_COERCIBLE(this, "String.prototype.toLowerCase");
+    var s = TO_STRING(this);
+    return %StringToLowerCaseI18N(s);
+  }
+);
+
+OverrideFunction(GlobalString.prototype, 'toUpperCase', function() {
+    if (!IS_UNDEFINED(new.target)) {
+      throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
+    }
+    CHECK_OBJECT_COERCIBLE(this, "String.prototype.toLowerCase");
+    var s = TO_STRING(this);
+    return %StringToUpperCaseI18N(s);
+  }
+);
+
+OverrideFunction(GlobalString.prototype, 'toLocaleLowerCase', function() {
+    if (!IS_UNDEFINED(new.target)) {
+      throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
+    }
+    CHECK_OBJECT_COERCIBLE(this, "String.prototype.toLocaleLowerCase");
+    return localeConvertCase(TO_STRING(this), arguments[0], false);
+  }
+);
+
+
+OverrideFunction(GlobalString.prototype, 'toLocaleUpperCase', function() {
+    if (!IS_UNDEFINED(new.target)) {
+      throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
+    }
+    CHECK_OBJECT_COERCIBLE(this, "String.prototype.toLocaleUpperCase");
+    return localeConvertCase(TO_STRING(this), arguments[0], true);
+  }
+);
+
 
 /**
  * Formats a Number object (this) using locale and options values.
  * If locale or options are omitted, defaults are used.
  */
 OverrideFunction(GlobalNumber.prototype, 'toLocaleString', function() {
     if (!IS_UNDEFINED(new.target)) {
       throw MakeTypeError(kOrdinaryFunctionCalledAsConstructor);
     }
 
@@ skipping 75 matching lines @@
     }
 
     var locales = arguments[0];
     var options = arguments[1];
     return toLocaleDateTime(
         this, locales, options, 'time', 'time', 'dateformattime');
   }
 );
 
 })