[intl] Add new semantics + compat fallback to Intl constructor

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.
  */
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var ArrayJoin;
 var ArrayPush;
 var GlobalDate = global.Date;
 var GlobalNumber = global.Number;
 var GlobalRegExp = global.RegExp;
 var GlobalString = global.String;
+var IntlFallbackSymbol = utils.ImportNow("intl_fallback_symbol");
 var InstallFunctions = utils.InstallFunctions;
 var InstallGetter = utils.InstallGetter;
 var InternalArray = utils.InternalArray;
 var ObjectHasOwnProperty = utils.ImportNow("ObjectHasOwnProperty");
 var OverrideFunction = utils.OverrideFunction;
 var patternSymbol = utils.ImportNow("intl_pattern_symbol");
 var resolvedSymbol = utils.ImportNow("intl_resolved_symbol");
 var SetFunctionName = utils.SetFunctionName;
 var StringSubstr = GlobalString.prototype.substr;
 var StringSubstring = GlobalString.prototype.substring;
@@ skipping 14 matching lines @@
   %CheckIsBootstrapping();
   SetFunctionName(func, name);
   %AddNamedProperty(object, name, func, DONT_ENUM);
   %SetNativeFlag(func);
   %ToFastProperties(object);
 }
 
 /**
  * Adds bound method to the prototype of the given object.
  */
-function AddBoundMethod(obj, methodName, implementation, length, type) {
+function AddBoundMethod(obj, methodName, implementation, length, typename, compat) {

[Yang, 2016/12/23 09:05:46]

80 char limit

[Dan Ehrenberg, 2016/12/23 14:01:53]

Done.

   %CheckIsBootstrapping();
   var internalName = %CreatePrivateSymbol(methodName);
   // Making getter an anonymous function will cause
   // %DefineGetterPropertyUnchecked to properly set the "name"
   // property on each JSFunction instance created here, rather
   // than (as utils.InstallGetter would) on the SharedFunctionInfo
   // associated with all functions returned from AddBoundMethod.
   var getter = ANONYMOUS_FUNCTION(function() {
-    if (!%IsInitializedIntlObjectOfType(this, type)) {
-      throw %make_type_error(kMethodCalledOnWrongObject, methodName);
-    }
-    if (IS_UNDEFINED(this[internalName])) {
+    var receiver = Unwrap(this, typename, obj, methodName, compat);
+    if (IS_UNDEFINED(receiver[internalName])) {
       var boundMethod;
       if (IS_UNDEFINED(length) || length === 2) {
         boundMethod =
-          ANONYMOUS_FUNCTION((fst, snd) => implementation(this, fst, snd));
+          ANONYMOUS_FUNCTION((fst, snd) => implementation(receiver, fst, snd));
       } else if (length === 1) {
-        boundMethod = ANONYMOUS_FUNCTION(fst => implementation(this, fst));
+        boundMethod = ANONYMOUS_FUNCTION(fst => implementation(receiver, fst));
       } else {
         boundMethod = ANONYMOUS_FUNCTION((...args) => {
           // DateTimeFormat.format needs to be 0 arg method, but can still
           // receive an optional dateValue param. If one was provided, pass it
           // along.
           if (args.length > 0) {
-            return implementation(this, args[0]);
+            return implementation(receiver, args[0]);
           } else {
-            return implementation(this);
+            return implementation(receiver);
           }
         });
       }
       %SetNativeFlag(boundMethod);
-      this[internalName] = boundMethod;
+      receiver[internalName] = boundMethod;
     }
-    return this[internalName];
+    return receiver[internalName];
   });
 
   %FunctionRemovePrototype(getter);
   %DefineGetterPropertyUnchecked(obj.prototype, methodName, getter, DONT_ENUM);
   %SetNativeFlag(getter);
 }
 
+function IntlConstruct(receiver, constructor, initializer, newTarget, args,
+                       compat) {
+  var locales = args[0];
+  var options = args[1];
+
+  if (IS_UNDEFINED(newTarget)) {
+    if (compat && receiver instanceof constructor) {
+      let success = %object_define_property(receiver, IntlFallbackSymbol,
+                           { value: new constructor(locales, options) });
+      if (!success) {
+        throw %make_type_error(kReinitializeIntl, constructor);
+      }
+      return receiver;
+    }
+
+    return new constructor(locales, options);
+  }
+
+  return initializer(receiver, locales, options);
+}
+
+
+
+function Unwrap(receiver, typename, constructor, method, compat) {
+  if (!%IsInitializedIntlObjectOfType(receiver, typename)) {
+    if (compat && receiver instanceof constructor) {
+      let fallback = receiver[IntlFallbackSymbol];
+      if (%IsInitializedIntlObjectOfType(fallback, typename)) {
+        return fallback;
+      }
+    }
+    throw %make_type_error(kIncompatibleMethodReceiver, method, receiver);
+  }
+  return receiver;
+}
+
+
 // -------------------------------------------------------------------
 
 var Intl = {};
 
 %AddNamedProperty(global, "Intl", Intl, DONT_ENUM);
 
 /**
  * Caches available locales for each service.
  */
 var AVAILABLE_LOCALES = {
@@ skipping 910 matching lines @@
   return collator;
 }
 
 
 /**
  * Constructs Intl.Collator object given optional locales and options
  * parameters.
  *
  * @constructor
  */
-InstallConstructor(Intl, 'Collator', function() {
-    var locales = arguments[0];
-    var options = arguments[1];
-
-    if (!this || this === Intl) {
-      // Constructor is called as a function.
-      return new Intl.Collator(locales, options);
-    }
-
-    return initializeCollator(TO_OBJECT(this), locales, options);
-  }
-);
+function Collator() {
+  return IntlConstruct(this, Collator, initializeCollator, new.target,
+                       arguments);
+}
+InstallConstructor(Intl, 'Collator', Collator);
 
 
 /**
  * Collator resolvedOptions method.
  */
 InstallFunction(Intl.Collator.prototype, 'resolvedOptions', function() {
-    if (!%IsInitializedIntlObjectOfType(this, 'collator')) {
-      throw %make_type_error(kResolvedOptionsCalledOnNonObject, "Collator");
-    }
-
-    var coll = this;
+    var coll = Unwrap(this, 'collator', Collator, 'resolvedOptions', false);
     var locale = getOptimalLanguageTag(coll[resolvedSymbol].requestedLocale,
                                        coll[resolvedSymbol].locale);
 
     return {
       locale: locale,
       usage: coll[resolvedSymbol].usage,
       sensitivity: coll[resolvedSymbol].sensitivity,
       ignorePunctuation: coll[resolvedSymbol].ignorePunctuation,
       numeric: coll[resolvedSymbol].numeric,
       caseFirst: coll[resolvedSymbol].caseFirst,
@@ skipping 24 matching lines @@
  * of this Collator object, and will be negative, zero, or positive, depending
  * on whether x comes before y in the sort order, the Strings are equal under
  * the sort order, or x comes after y in the sort order, respectively.
  */
 function compare(collator, x, y) {
   return %InternalCompare(%GetImplFromInitializedIntlObject(collator),
                           TO_STRING(x), TO_STRING(y));
 };
 
 
-AddBoundMethod(Intl.Collator, 'compare', compare, 2, 'collator');
+AddBoundMethod(Intl.Collator, 'compare', compare, 2, 'collator', false);
 
 /**
  * Verifies that the input is a well-formed ISO 4217 currency code.
  * Don't uppercase to test. It could convert invalid code into a valid one.
  * For example \u00DFP (Eszett+P) becomes SSP.
  */
 function isWellFormedCurrencyCode(currency) {
   return typeof currency == "string" && currency.length == 3 &&
       IS_NULL(%regexp_internal_match(/[^A-Za-z]/, currency));
 }
@@ skipping 145 matching lines @@
   return numberFormat;
 }
 
 
 /**
  * Constructs Intl.NumberFormat object given optional locales and options
  * parameters.
  *
  * @constructor
  */
-InstallConstructor(Intl, 'NumberFormat', function() {
-    var locales = arguments[0];
-    var options = arguments[1];
-
-    if (!this || this === Intl) {
-      // Constructor is called as a function.
-      return new Intl.NumberFormat(locales, options);
-    }
-
-    return initializeNumberFormat(TO_OBJECT(this), locales, options);
-  }
-);
+function NumberFormat() {
+  return IntlConstruct(this, NumberFormat, initializeNumberFormat, new.target,
+                       arguments, true);
+}
+InstallConstructor(Intl, 'NumberFormat', NumberFormat);
 
 
 /**
  * NumberFormat resolvedOptions method.
  */
 InstallFunction(Intl.NumberFormat.prototype, 'resolvedOptions', function() {
-    if (!%IsInitializedIntlObjectOfType(this, 'numberformat')) {
-      throw %make_type_error(kResolvedOptionsCalledOnNonObject, "NumberFormat");
-    }
-
-    var format = this;
+    var format = Unwrap(this, 'numberformat', NumberFormat,
+                        'resolvedOptions', true);
     var locale = getOptimalLanguageTag(format[resolvedSymbol].requestedLocale,
                                        format[resolvedSymbol].locale);
 
     var result = {
       locale: locale,
       numberingSystem: format[resolvedSymbol].numberingSystem,
       style: format[resolvedSymbol].style,
       useGrouping: format[resolvedSymbol].useGrouping,
       minimumIntegerDigits: format[resolvedSymbol].minimumIntegerDigits,
       minimumFractionDigits: format[resolvedSymbol].minimumFractionDigits,
@@ skipping 40 matching lines @@
  */
 function formatNumber(formatter, value) {
   // Spec treats -0 and +0 as 0.
   var number = TO_NUMBER(value) + 0;
 
   return %InternalNumberFormat(%GetImplFromInitializedIntlObject(formatter),
                                number);
 }
 
 
-AddBoundMethod(Intl.NumberFormat, 'format', formatNumber, 1, 'numberformat');
+AddBoundMethod(Intl.NumberFormat, 'format', formatNumber, 1, 'numberformat', true);
 
 /**
  * Returns a string that matches LDML representation of the options object.
  */
 function toLDMLString(options) {
   var getOption = getGetOption(options, 'dateformat');
 
   var ldmlString = '';
 
   var option = getOption('weekday', 'string', ['narrow', 'short', 'long']);
@@ skipping 272 matching lines @@
   return dateFormat;
 }
 
 
 /**
  * Constructs Intl.DateTimeFormat object given optional locales and options
  * parameters.
  *
  * @constructor
  */
-InstallConstructor(Intl, 'DateTimeFormat', function() {
-    var locales = arguments[0];
-    var options = arguments[1];
-
-    if (!this || this === Intl) {
-      // Constructor is called as a function.
-      return new Intl.DateTimeFormat(locales, options);
-    }
-
-    return initializeDateTimeFormat(TO_OBJECT(this), locales, options);
-  }
-);
+function DateTimeFormat() {
+  return IntlConstruct(this, DateTimeFormat, initializeDateTimeFormat,
+                       new.target, arguments, true);
+}
+InstallConstructor(Intl, 'DateTimeFormat', DateTimeFormat);
 
 
 /**
  * DateTimeFormat resolvedOptions method.
  */
 InstallFunction(Intl.DateTimeFormat.prototype, 'resolvedOptions', function() {
-    if (!%IsInitializedIntlObjectOfType(this, 'dateformat')) {
-      throw %make_type_error(kResolvedOptionsCalledOnNonObject, "DateTimeFormat");
-    }
+    var format = Unwrap(this, 'dateformat', DateTimeFormat,
+                        'resolvedOptions', true);
 
     /**
      * Maps ICU calendar names to LDML/BCP47 types for key 'ca'.
      * See typeMap section in third_party/icu/source/data/misc/keyTypeData.txt
      * and
      * http://www.unicode.org/repos/cldr/tags/latest/common/bcp47/calendar.xml
      */
     var ICU_CALENDAR_MAP = {
       'gregorian': 'gregory',
       'ethiopic-amete-alem': 'ethioaa'
     };
 
-    var format = this;
     var fromPattern = fromLDMLString(format[resolvedSymbol][patternSymbol]);
     var userCalendar = ICU_CALENDAR_MAP[format[resolvedSymbol].calendar];
     if (IS_UNDEFINED(userCalendar)) {
       // No match means that ICU's legacy name is identical to LDML/BCP type.
       userCalendar = format[resolvedSymbol].calendar;
     }
 
     var locale = getOptimalLanguageTag(format[resolvedSymbol].requestedLocale,
                                        format[resolvedSymbol].locale);
 
@@ skipping 66 matching lines @@
   if (!NUMBER_IS_FINITE(dateMs)) throw %make_range_error(kDateRange);
 
   return %InternalDateFormatToParts(
       %GetImplFromInitializedIntlObject(this), new GlobalDate(dateMs));
 }
 
 %FunctionSetLength(FormatDateToParts, 0);
 
 
 // 0 because date is optional argument.
-AddBoundMethod(Intl.DateTimeFormat, 'format', formatDate, 0, 'dateformat');
+AddBoundMethod(Intl.DateTimeFormat, 'format', formatDate, 0, 'dateformat', true);
 
 
 /**
  * Returns canonical Area/Location(/Location) name, or throws an exception
  * if the zone name is invalid IANA name.
  */
 function canonicalizeTimeZoneID(tzID) {
   // Skip undefined zones.
   if (IS_UNDEFINED(tzID)) {
     return tzID;
@@ skipping 68 matching lines @@
   return iterator;
 }
 
 
 /**
  * Constructs Intl.v8BreakIterator object given optional locales and options
  * parameters.
  *
  * @constructor
  */
-InstallConstructor(Intl, 'v8BreakIterator', function() {
-    var locales = arguments[0];
-    var options = arguments[1];
-
-    if (!this || this === Intl) {
-      // Constructor is called as a function.
-      return new Intl.v8BreakIterator(locales, options);
-    }
-
-    return initializeBreakIterator(TO_OBJECT(this), locales, options);
-  }
-);
+function v8BreakIterator() {
+  return IntlConstruct(this, v8BreakIterator, initializeBreakIterator,
+                       new.target, arguments);
+}
+InstallConstructor(Intl, 'v8BreakIterator', v8BreakIterator);
 
 
 /**
  * BreakIterator resolvedOptions method.
  */
 InstallFunction(Intl.v8BreakIterator.prototype, 'resolvedOptions',
   function() {
     if (!IS_UNDEFINED(new.target)) {
       throw %make_type_error(kOrdinaryFunctionCalledAsConstructor);
     }
 
-    if (!%IsInitializedIntlObjectOfType(this, 'breakiterator')) {
-      throw %make_type_error(kResolvedOptionsCalledOnNonObject, "v8BreakIterator");
-    }
+    var segmenter = Unwrap(this, 'breakiterator', v8BreakIterator,
+                           'resolvedOptions', false);
 
-    var segmenter = this;
     var locale =
         getOptimalLanguageTag(segmenter[resolvedSymbol].requestedLocale,
                               segmenter[resolvedSymbol].locale);
 
     return {
       locale: locale,
       type: segmenter[resolvedSymbol].type
     };
   }
 );
@@ skipping 310 matching lines @@
   }
 );
 
 %FunctionRemovePrototype(FormatDateToParts);
 
 utils.Export(function(to) {
   to.FormatDateToParts = FormatDateToParts;
 });
 
 })