Perform more aggressive time to NaN conversions. Our internal date...

src/date.js

 // Copyright 2006-2008 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
@@ skipping 63 matching lines @@
       + FLOOR((year-1601)/400);
 }
 
 
 function TimeFromYear(year) {
   return msPerDay * DayFromYear(year);
 }
 
 
 function InLeapYear(time) {
-  return DaysInYear(YEAR_FROM_TIME(time)) == 366 ? 1 : 0;
+  return DaysInYear(YearFromTime(time)) == 366 ? 1 : 0;
 }
 
 
 function DayWithinYear(time) {
-  return DAY(time) - DayFromYear(YEAR_FROM_TIME(time));
+  return DAY(time) - DayFromYear(YearFromTime(time));
 }
 
 
 // ECMA 262 - 15.9.1.9
 function EquivalentYear(year) {
   // Returns an equivalent year in the range [2008-2035] matching
   // - leap year.
   // - week day of first day.
   var time = TimeFromYear(year);
   var recent_year = (InLeapYear(time) == 0 ? 1967 : 1956) +
       (WeekDay(time) * 12) % 28;
   // Find the year in the range 2008..2037 that is equivalent mod 28.
   // Add 3*28 to give a positive argument to the modulus operator.
   return 2008 + (recent_year + 3*28 - 2008) % 28;
 }
 
 
 function EquivalentTime(t) {
   // The issue here is that some library calls don't work right for dates
   // that cannot be represented using a non-negative signed 32 bit integer
   // (measured in whole seconds based on the 1970 epoch).
   // We solve this by mapping the time to a year with same leap-year-ness
   // and same starting day for the year.  The ECMAscript specification says
   // we must do this, but for compatibility with other browsers, we use
   // the actual year if it is in the range 1970..2037
   if (t >= 0 && t <= 2.1e12) return t;
 
-  var day = MakeDay(EquivalentYear(YEAR_FROM_TIME(t)),
-                    MONTH_FROM_TIME(t),
-                    DATE_FROM_TIME(t));
+  var day = MakeDay(EquivalentYear(YearFromTime(t)),
+                    MonthFromTime(t),
+                    DateFromTime(t));
   return MakeDate(day, TimeWithinDay(t));
 }
 
 
 // local_time_offset is initialized when the DST_offset_cache is missed.
 // It must not be used until after a call to DaylightSavingsOffset().
 // In this way, only one check, for a DST cache miss, is needed.
 var local_time_offset;
 
 
@@ skipping 116 matching lines @@
 
 
 var ltcache = {
   key: null,
   val: null
 };
 
 function LocalTimeNoCheck(time) {
   var ltc = ltcache;
   if (%_ObjectEquals(time, ltc.key)) return ltc.val;
-  if (time < -MAX_TIME_MS || time > MAX_TIME_MS) {
-    return $NaN;
-  }
 
   // Inline the DST offset cache checks for speed.
   // The cache is hit, or DaylightSavingsOffset is called,
   // before local_time_offset is used.
   var cache = DST_offset_cache;
   if (cache.start <= time && time <= cache.end) {
     var dst_offset = cache.offset;
   } else {
     var dst_offset = DaylightSavingsOffset(time);
   }
@@ skipping 95 matching lines @@
     return $NaN;
   }
 
   // Now we rely on year, month and date being SMIs.
   return %DateMakeDay(year, month, date);
 }
 
 
 // ECMA 262 - 15.9.1.13
 function MakeDate(day, time) {
-  if (!$isFinite(day)) return $NaN;
-  if (!$isFinite(time)) return $NaN;
-  return day * msPerDay + time;
+  var time = day * msPerDay + time;

[Søren Thygesen Gjesse, 2010/12/16 11:38:30]

As you mentioned offline please add tests where day and time have different
Infinity/-Infinity values to ensure NaN is returned.

+  // Some of our runtime funtions for computing UTC(time) rely on
+  // times not being significantly larger than MAX_TIME_MS. If there
+  // is no way that the time can be within range even after UTC
+  // conversion we return NaN immediately instead of relying on
+  // TimeClip to do it.
+  if ($abs(time) > MAX_TIME_BEFORE_UTC) return $NaN;
+  return time;
 }
 
 
 // ECMA 262 - 15.9.1.14
 function TimeClip(time) {
   if (!$isFinite(time)) return $NaN;
-  if ($abs(time) > 8.64E15) return $NaN;
+  if ($abs(time) > MAX_TIME_MS) return $NaN;
   return TO_INTEGER(time);
 }
 
 
 // The Date cache is used to limit the cost of parsing the same Date
 // strings over and over again.
 var Date_cache = {
   // Cached time value.
   time: $NaN,
   // Cached year when interpreting the time as a local time. Only
@@ skipping 23 matching lines @@
     } else if (IS_STRING(year)) {
       // Probe the Date cache. If we already have a time value for the
       // given time, we re-use that instead of parsing the string again.
       var cache = Date_cache;
       if (cache.string === year) {
         value = cache.time;
       } else {
         value = DateParse(year);
         if (!NUMBER_IS_NAN(value)) {
           cache.time = value;
-          cache.year = YEAR_FROM_TIME(LocalTimeNoCheck(value));
+          cache.year = YearFromTime(LocalTimeNoCheck(value));
           cache.string = year;
         }
       }
 
     } else {
       // According to ECMA 262, no hint should be given for this
       // conversion. However, ToPrimitive defaults to STRING_HINT for
       // Date objects which will lose precision when the Date
       // constructor is called with another Date object as its
       // argument. We therefore use NUMBER_HINT for the conversion,
@@ skipping 197 matching lines @@
   return DATE_VALUE(this);
 }
 
 
 // ECMA 262 - 15.9.5.10
 function DateGetFullYear() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return t;
   var cache = Date_cache;
   if (cache.time === t) return cache.year;
-  return YEAR_FROM_TIME(LocalTimeNoCheck(t));
+  return YearFromTime(LocalTimeNoCheck(t));
 }
 
 
 // ECMA 262 - 15.9.5.11
 function DateGetUTCFullYear() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return t;
-  return YEAR_FROM_TIME(t);
+  return YearFromTime(t);
 }
 
 
 // ECMA 262 - 15.9.5.12
 function DateGetMonth() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return t;
-  return MONTH_FROM_TIME(LocalTimeNoCheck(t));
+  return MonthFromTime(LocalTimeNoCheck(t));
 }
 
 
 // ECMA 262 - 15.9.5.13
 function DateGetUTCMonth() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return t;
-  return MONTH_FROM_TIME(t);
+  return MonthFromTime(t);
 }
 
 
 // ECMA 262 - 15.9.5.14
 function DateGetDate() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return t;
-  return DATE_FROM_TIME(LocalTimeNoCheck(t));
+  return DateFromTime(LocalTimeNoCheck(t));
 }
 
 
 // ECMA 262 - 15.9.5.15
 function DateGetUTCDate() {
   var t = DATE_VALUE(this);
   return NAN_OR_DATE_FROM_TIME(t);
 }
 
 
@@ skipping 174 matching lines @@
   ms = argc < 4 ? NAN_OR_MS_FROM_TIME(t) : ToNumber(ms);
   var time = MakeTime(hour, min, sec, ms);
   return %_SetValueOf(this, TimeClip(MakeDate(DAY(t), time)));
 }
 
 
 // ECMA 262 - 15.9.5.36
 function DateSetDate(date) {
   var t = LocalTime(DATE_VALUE(this));
   date = ToNumber(date);
-  var day = MakeDay(YEAR_FROM_TIME(t), MONTH_FROM_TIME(t), date);
+  var day = MakeDay(YearFromTime(t), MonthFromTime(t), date);
   return %_SetValueOf(this, TimeClip(UTC(MakeDate(day, TimeWithinDay(t)))));
 }
 
 
 // ECMA 262 - 15.9.5.37
 function DateSetUTCDate(date) {
   var t = DATE_VALUE(this);
   date = ToNumber(date);
-  var day = MakeDay(YEAR_FROM_TIME(t), MONTH_FROM_TIME(t), date);
+  var day = MakeDay(YearFromTime(t), MonthFromTime(t), date);
   return %_SetValueOf(this, TimeClip(MakeDate(day, TimeWithinDay(t))));
 }
 
 
 // ECMA 262 - 15.9.5.38
 function DateSetMonth(month, date) {
   var t = LocalTime(DATE_VALUE(this));
   month = ToNumber(month);
   date = %_ArgumentsLength() < 2 ? NAN_OR_DATE_FROM_TIME(t) : ToNumber(date);
-  var day = MakeDay(YEAR_FROM_TIME(t), month, date);
+  var day = MakeDay(YearFromTime(t), month, date);
   return %_SetValueOf(this, TimeClip(UTC(MakeDate(day, TimeWithinDay(t)))));
 }
 
 
 // ECMA 262 - 15.9.5.39
 function DateSetUTCMonth(month, date) {
   var t = DATE_VALUE(this);
   month = ToNumber(month);
   date = %_ArgumentsLength() < 2 ? NAN_OR_DATE_FROM_TIME(t) : ToNumber(date);
-  var day = MakeDay(YEAR_FROM_TIME(t), month, date);
+  var day = MakeDay(YearFromTime(t), month, date);
   return %_SetValueOf(this, TimeClip(MakeDate(day, TimeWithinDay(t))));
 }
 
 
 // ECMA 262 - 15.9.5.40
 function DateSetFullYear(year, month, date) {
   var t = DATE_VALUE(this);
   t = NUMBER_IS_NAN(t) ? 0 : LocalTimeNoCheck(t);
   year = ToNumber(year);
   var argc = %_ArgumentsLength();
-  month = argc < 2 ? MONTH_FROM_TIME(t) : ToNumber(month);
-  date = argc < 3 ? DATE_FROM_TIME(t) : ToNumber(date);
+  month = argc < 2 ? MonthFromTime(t) : ToNumber(month);
+  date = argc < 3 ? DateFromTime(t) : ToNumber(date);
   var day = MakeDay(year, month, date);
   return %_SetValueOf(this, TimeClip(UTC(MakeDate(day, TimeWithinDay(t)))));
 }
 
 
 // ECMA 262 - 15.9.5.41
 function DateSetUTCFullYear(year, month, date) {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) t = 0;
   var argc = %_ArgumentsLength();
   year = ToNumber(year);
-  month = argc < 2 ? MONTH_FROM_TIME(t) : ToNumber(month);
-  date = argc < 3 ? DATE_FROM_TIME(t) : ToNumber(date);
+  month = argc < 2 ? MonthFromTime(t) : ToNumber(month);
+  date = argc < 3 ? DateFromTime(t) : ToNumber(date);
   var day = MakeDay(year, month, date);
   return %_SetValueOf(this, TimeClip(MakeDate(day, TimeWithinDay(t))));
 }
 
 
 // ECMA 262 - 15.9.5.42
 function DateToUTCString() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return kInvalidDate;
   // Return UTC string of the form: Sat, 31 Jan 1970 23:00:00 GMT
   return WeekDays[WeekDay(t)] + ', '
-      + TwoDigitString(DATE_FROM_TIME(t)) + ' '
-      + Months[MONTH_FROM_TIME(t)] + ' '
-      + YEAR_FROM_TIME(t) + ' '
+      + TwoDigitString(DateFromTime(t)) + ' '
+      + Months[MonthFromTime(t)] + ' '
+      + YearFromTime(t) + ' '
       + TimeString(t) + ' GMT';
 }
 
 
 // ECMA 262 - B.2.4
 function DateGetYear() {
   var t = DATE_VALUE(this);
   if (NUMBER_IS_NAN(t)) return $NaN;
-  return YEAR_FROM_TIME(LocalTimeNoCheck(t)) - 1900;
+  return YearFromTime(LocalTimeNoCheck(t)) - 1900;
 }
 
 
 // ECMA 262 - B.2.5
 function DateSetYear(year) {
   var t = LocalTime(DATE_VALUE(this));
   if (NUMBER_IS_NAN(t)) t = 0;
   year = ToNumber(year);
   if (NUMBER_IS_NAN(year)) return %_SetValueOf(this, $NaN);
   year = (0 <= TO_INTEGER(year) && TO_INTEGER(year) <= 99)
       ? 1900 + TO_INTEGER(year) : year;
-  var day = MakeDay(year, MONTH_FROM_TIME(t), DATE_FROM_TIME(t));
+  var day = MakeDay(year, MonthFromTime(t), DateFromTime(t));
   return %_SetValueOf(this, TimeClip(UTC(MakeDate(day, TimeWithinDay(t)))));
 }
 
 
 // ECMA 262 - B.2.6
 //
 // Notice that this does not follow ECMA 262 completely.  ECMA 262
 // says that toGMTString should be the same Function object as
 // toUTCString.  JSC does not do this, so for compatibility we do not
 // do that either.  Instead, we create a new function whose name
@@ skipping 92 matching lines @@
     "toGMTString", DateToGMTString,
     "toUTCString", DateToUTCString,
     "getYear", DateGetYear,
     "setYear", DateSetYear,
     "toISOString", DateToISOString,
     "toJSON", DateToJSON
   ));
 }
 
 SetupDate();