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/*---
defines: [msPerHour, TZ_ADJUST, UTC_01_JAN_1900, UTC_01_JAN_2000, UTC_29_FEB_2000, UTC_01_JAN_2005, inTimeZone, withLocale, Month, assertDateTime, runDSTOffsetCachingTestsFraction]
allow_unused: True
---*/
/**
* Date functions used by tests in Date suite
*/
(function(global) {
const msPerDay = 1000 * 60 * 60 * 24;
const msPerHour = 1000 * 60 * 60;
global.msPerHour = msPerHour;
// Offset of tester's time zone from UTC.
const TZ_DIFF = GetRawTimezoneOffset();
global.TZ_ADJUST = TZ_DIFF * msPerHour;
const UTC_01_JAN_1900 = -2208988800000;
const UTC_01_JAN_2000 = 946684800000;
const UTC_29_FEB_2000 = UTC_01_JAN_2000 + 31 * msPerDay + 28 * msPerDay;
const UTC_01_JAN_2005 = UTC_01_JAN_2000 + TimeInYear(2000) + TimeInYear(2001) +
TimeInYear(2002) + TimeInYear(2003) + TimeInYear(2004);
global.UTC_01_JAN_1900 = UTC_01_JAN_1900;
global.UTC_01_JAN_2000 = UTC_01_JAN_2000;
global.UTC_29_FEB_2000 = UTC_29_FEB_2000;
global.UTC_01_JAN_2005 = UTC_01_JAN_2005;
/*
* Originally, the test suite used a hard-coded value TZ_DIFF = -8.
* But that was only valid for testers in the Pacific Standard Time Zone!
* We calculate the proper number dynamically for any tester. We just
* have to be careful not to use a date subject to Daylight Savings Time...
*/
function GetRawTimezoneOffset() {
let t1 = new Date(2000, 1, 1).getTimezoneOffset();
let t2 = new Date(2000, 1 + 6, 1).getTimezoneOffset();
// 1) Time zone without daylight saving time.
// 2) Northern hemisphere with daylight saving time.
if ((t1 - t2) >= 0)
return -t1 / 60;
// 3) Southern hemisphere with daylight saving time.
return -t2 / 60;
}
function DaysInYear(y) {
return y % 4 === 0 && (y % 100 !== 0 || y % 400 === 0) ? 366 : 365;
}
function TimeInYear(y) {
return DaysInYear(y) * msPerDay;
}
function getDefaultTimeZone() {
var tz = getTimeZone();
switch (tz) {
case "EST":
case "EDT":
return "EST5EDT";
case "CST":
case "CDT":
return "CST6CDT";
case "MST":
case "MDT":
return "MST7MDT";
case "PST":
case "PDT":
return "PST8PDT";
default:
// Other time zones abbrevations are not supported.
return tz;
}
}
function getDefaultLocale() {
// If the default locale looks like a BCP-47 language tag, return it.
var locale = global.getDefaultLocale();
if (locale.match(/^[a-z][a-z0-9\-]+$/i))
return locale;
// Otherwise use undefined to reset to the default locale.
return undefined;
}
let defaultTimeZone = null;
let defaultLocale = null;
// Run the given test in the requested time zone.
function inTimeZone(tzname, fn) {
if (defaultTimeZone === null)
defaultTimeZone = getDefaultTimeZone();
setTimeZone(tzname);
try {
fn();
} finally {
setTimeZone(defaultTimeZone);
}
}
global.inTimeZone = inTimeZone;
// Run the given test with the requested locale.
function withLocale(locale, fn) {
if (defaultLocale === null)
defaultLocale = getDefaultLocale();
setDefaultLocale(locale);
try {
fn();
} finally {
setDefaultLocale(defaultLocale);
}
}
global.withLocale = withLocale;
const Month = {
January: 0,
February: 1,
March: 2,
April: 3,
May: 4,
June: 5,
July: 6,
August: 7,
September: 8,
October: 9,
November: 10,
December: 11,
};
global.Month = Month;
const weekdays = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"].join("|");
const months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"].join("|");
const datePart = String.raw `(?:${weekdays}) (?:${months}) \d{2}`;
const timePart = String.raw `\d{4,6} \d{2}:\d{2}:\d{2} GMT[+-]\d{4}`;
const dateTimeRE = new RegExp(String.raw `^(${datePart} ${timePart})(?: \((.+)\))?$`);
function assertDateTime(date, expected, ...alternativeTimeZones) {
let actual = date.toString();
assertEq(dateTimeRE.test(expected), true, `${expected}`);
assertEq(dateTimeRE.test(actual), true, `${actual}`);
let [, expectedDateTime, expectedTimeZone] = dateTimeRE.exec(expected);
let [, actualDateTime, actualTimeZone] = dateTimeRE.exec(actual);
assertEq(actualDateTime, expectedDateTime);
// The time zone identifier is optional, so only compare its value if
// it's present in |actual| and |expected|.
if (expectedTimeZone !== undefined && actualTimeZone !== undefined) {
// Test against the alternative time zone identifiers if necessary.
if (actualTimeZone !== expectedTimeZone) {
for (let alternativeTimeZone of alternativeTimeZones) {
if (actualTimeZone === alternativeTimeZone) {
expectedTimeZone = alternativeTimeZone;
break;
}
}
}
assertEq(actualTimeZone, expectedTimeZone);
}
}
global.assertDateTime = assertDateTime;
})(this);
function runDSTOffsetCachingTestsFraction(part, parts)
{
var BUGNUMBER = 563938;
var summary = 'Cache DST offsets to improve SunSpider score';
print(BUGNUMBER + ": " + summary);
var MAX_UNIX_TIMET = 2145859200; // "2037-12-31T08:00:00.000Z" (PST8PDT based!)
var RANGE_EXPANSION_AMOUNT = 30 * 24 * 60 * 60;
/**
* Computes the time zone offset in minutes at the given timestamp.
*/
function tzOffsetFromUnixTimestamp(timestamp)
{
var d = new Date(NaN);
d.setTime(timestamp); // local slot = NaN, UTC slot = timestamp
return d.getTimezoneOffset(); // get UTC, calculate local => diff in minutes
}
/**
* Clear the DST offset cache, leaving it initialized to include a timestamp
* completely unlike the provided one (i.e. one very, very far away in time
* from it). Thus an immediately following lookup for the provided timestamp
* will cache-miss and compute a clean value.
*/
function clearDSTOffsetCache(undesiredTimestamp)
{
var opposite = (undesiredTimestamp + MAX_UNIX_TIMET / 2) % MAX_UNIX_TIMET;
// Generic purge to known, but not necessarily desired, state
tzOffsetFromUnixTimestamp(0);
tzOffsetFromUnixTimestamp(MAX_UNIX_TIMET);
// Purge to desired state. Cycle 2x in case opposite or undesiredTimestamp
// is close to 0 or MAX_UNIX_TIMET.
tzOffsetFromUnixTimestamp(opposite);
tzOffsetFromUnixTimestamp(undesiredTimestamp);
tzOffsetFromUnixTimestamp(opposite);
tzOffsetFromUnixTimestamp(undesiredTimestamp);
}
function computeCanonicalTZOffset(timestamp)
{
clearDSTOffsetCache(timestamp);
return tzOffsetFromUnixTimestamp(timestamp);
}
var TEST_TIMESTAMPS_SECONDS =
[
// Special-ish timestamps
0,
RANGE_EXPANSION_AMOUNT,
MAX_UNIX_TIMET,
];
var ONE_DAY = 24 * 60 * 60;
var EIGHTY_THREE_HOURS = 83 * 60 * 60;
var NINETY_EIGHT_HOURS = 98 * 60 * 60;
function nextIncrement(i)
{
return i === EIGHTY_THREE_HOURS ? NINETY_EIGHT_HOURS : EIGHTY_THREE_HOURS;
}
// Now add a long sequence of non-special timestamps, from a fixed range, that
// overlaps a DST change by "a bit" on each side. 67 days should be enough
// displacement that we can occasionally exercise the implementation's
// thirty-day expansion and the DST-offset-change logic. Use two different
// increments just to be safe and catch something a single increment might not.
var DST_CHANGE_DATE = 1268553600; // March 14, 2010
for (var t = DST_CHANGE_DATE - 67 * ONE_DAY,
i = nextIncrement(NINETY_EIGHT_HOURS),
end = DST_CHANGE_DATE + 67 * ONE_DAY;
t < end;
i = nextIncrement(i), t += i)
{
TEST_TIMESTAMPS_SECONDS.push(t);
}
var TEST_TIMESTAMPS =
TEST_TIMESTAMPS_SECONDS.map(function(v) { return v * 1000; });
/**************
* BEGIN TEST *
**************/
// Compute the correct time zone offsets for all timestamps to be tested.
var CORRECT_TZOFFSETS = TEST_TIMESTAMPS.map(computeCanonicalTZOffset);
// Intentionally and knowingly invoking every single logic path in the cache
// isn't easy for a human to get right (and know he's gotten it right), so
// let's do it the easy way: exhaustively try all possible four-date sequences
// selecting from our array of possible timestamps.
var sz = TEST_TIMESTAMPS.length;
var start = Math.floor((part - 1) / parts * sz);
var end = Math.floor(part / parts * sz);
print("Exhaustively testing timestamps " +
"[" + start + ", " + end + ") of " + sz + "...");
try
{
for (var i = start; i < end; i++)
{
print("Testing timestamp " + i + "...");
var t1 = TEST_TIMESTAMPS[i];
for (var j = 0; j < sz; j++)
{
var t2 = TEST_TIMESTAMPS[j];
for (var k = 0; k < sz; k++)
{
var t3 = TEST_TIMESTAMPS[k];
for (var w = 0; w < sz; w++)
{
var t4 = TEST_TIMESTAMPS[w];
clearDSTOffsetCache(t1);
var tzo1 = tzOffsetFromUnixTimestamp(t1);
var tzo2 = tzOffsetFromUnixTimestamp(t2);
var tzo3 = tzOffsetFromUnixTimestamp(t3);
var tzo4 = tzOffsetFromUnixTimestamp(t4);
assertEq(tzo1, CORRECT_TZOFFSETS[i]);
assertEq(tzo2, CORRECT_TZOFFSETS[j]);
assertEq(tzo3, CORRECT_TZOFFSETS[k]);
assertEq(tzo4, CORRECT_TZOFFSETS[w]);
}
}
}
}
}
catch (e)
{
assertEq(true, false,
"Error when testing with timestamps " +
i + ", " + j + ", " + k + ", " + w +
" (" + t1 + ", " + t2 + ", " + t3 + ", " + t4 + ")!");
}
reportCompare(true, true);
print("All tests passed!");
}