Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* JS date methods.
*
* "For example, OS/360 devotes 26 bytes of the permanently
* resident date-turnover routine to the proper handling of
* December 31 on leap years (when it is Day 366). That
* might have been left to the operator."
*
* Frederick Brooks, 'The Second-System Effect'.
*/
#include "jsdate.h"
#include "mozilla/Atomics.h"
#include "mozilla/Casting.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/TextUtils.h"
#include <algorithm>
#include <cstring>
#include <iterator>
#include <math.h>
#include <string.h>
#include "jsapi.h"
#include "jsfriendapi.h"
#include "jsnum.h"
#include "jstypes.h"
#ifdef JS_HAS_TEMPORAL_API
# include "builtin/temporal/Instant.h"
#endif
#include "jit/InlinableNatives.h"
#include "js/CallAndConstruct.h" // JS::IsCallable
#include "js/Conversions.h"
#include "js/Date.h"
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#include "js/LocaleSensitive.h"
#include "js/Object.h" // JS::GetBuiltinClass
#include "js/PropertySpec.h"
#include "js/Wrapper.h"
#include "util/DifferentialTesting.h"
#include "util/StringBuilder.h"
#include "util/Text.h"
#include "vm/DateObject.h"
#include "vm/DateTime.h"
#include "vm/GlobalObject.h"
#include "vm/Interpreter.h"
#include "vm/JSContext.h"
#include "vm/JSObject.h"
#include "vm/StringType.h"
#include "vm/Time.h"
#include "vm/Compartment-inl.h" // For js::UnwrapAndTypeCheckThis
#include "vm/GeckoProfiler-inl.h"
#include "vm/JSObject-inl.h"
using namespace js;
using mozilla::Atomic;
using mozilla::BitwiseCast;
using mozilla::IsAsciiAlpha;
using mozilla::IsAsciiDigit;
using mozilla::IsAsciiLowercaseAlpha;
using mozilla::NumbersAreIdentical;
using mozilla::Relaxed;
using JS::AutoCheckCannotGC;
using JS::ClippedTime;
using JS::GenericNaN;
using JS::GetBuiltinClass;
using JS::TimeClip;
using JS::ToInteger;
// When this value is non-zero, we'll round the time by this resolution.
static Atomic<uint32_t, Relaxed> sResolutionUsec;
// This is not implemented yet, but we will use this to know to jitter the time
// in the JS shell
static Atomic<bool, Relaxed> sJitter;
// The callback we will use for the Gecko implementation of Timer
// Clamping/Jittering
static Atomic<JS::ReduceMicrosecondTimePrecisionCallback, Relaxed>
sReduceMicrosecondTimePrecisionCallback;
namespace {
class DateTimeHelper {
private:
#if !JS_HAS_INTL_API
static int equivalentYearForDST(int year);
static bool isRepresentableAsTime32(int64_t t);
static int32_t daylightSavingTA(DateTimeInfo::ForceUTC forceUTC, int64_t t);
static int32_t adjustTime(DateTimeInfo::ForceUTC forceUTC, int64_t date);
static PRMJTime toPRMJTime(DateTimeInfo::ForceUTC forceUTC, int64_t localTime,
int64_t utcTime);
#endif
public:
static int32_t getTimeZoneOffset(DateTimeInfo::ForceUTC forceUTC,
int64_t epochMilliseconds,
DateTimeInfo::TimeZoneOffset offset);
static JSString* timeZoneComment(JSContext* cx,
DateTimeInfo::ForceUTC forceUTC,
const char* locale, int64_t utcTime,
int64_t localTime);
#if !JS_HAS_INTL_API
static size_t formatTime(DateTimeInfo::ForceUTC forceUTC, char* buf,
size_t buflen, const char* fmt, int64_t utcTime,
int64_t localTime);
#endif
};
} // namespace
static DateTimeInfo::ForceUTC ForceUTC(const Realm* realm) {
return realm->creationOptions().forceUTC() ? DateTimeInfo::ForceUTC::Yes
: DateTimeInfo::ForceUTC::No;
}
/**
* 5.2.5 Mathematical Operations
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline double PositiveModulo(double dividend, double divisor) {
MOZ_ASSERT(divisor > 0);
MOZ_ASSERT(std::isfinite(divisor));
double result = fmod(dividend, divisor);
if (result < 0) {
result += divisor;
}
return result + (+0.0);
}
template <typename T>
static inline std::enable_if_t<std::is_integral_v<T>, int32_t> PositiveModulo(
T dividend, int32_t divisor) {
MOZ_ASSERT(divisor > 0);
int32_t result = dividend % divisor;
if (result < 0) {
result += divisor;
}
return result;
}
template <typename T>
static constexpr T FloorDiv(T dividend, int32_t divisor) {
MOZ_ASSERT(divisor > 0);
T quotient = dividend / divisor;
T remainder = dividend % divisor;
if (remainder < 0) {
quotient -= 1;
}
return quotient;
}
#ifdef DEBUG
/**
* 21.4.1.1 Time Values and Time Range
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline bool IsTimeValue(double t) {
if (std::isnan(t)) {
return true;
}
return IsInteger(t) && StartOfTime <= t && t <= EndOfTime;
}
#endif
/**
* Time value with local time zone offset applied.
*/
static inline bool IsLocalTimeValue(double t) {
if (std::isnan(t)) {
return true;
}
return IsInteger(t) && (StartOfTime - msPerDay) < t &&
t < (EndOfTime + msPerDay);
}
/**
* 21.4.1.3 Day ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline int32_t Day(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return int32_t(FloorDiv(t, msPerDay));
}
/**
* 21.4.1.4 TimeWithinDay ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t TimeWithinDay(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return PositiveModulo(t, msPerDay);
}
/**
* 21.4.1.5 DaysInYear ( y )
* 21.4.1.10 InLeapYear ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline bool IsLeapYear(double year) {
MOZ_ASSERT(IsInteger(year));
return fmod(year, 4) == 0 && (fmod(year, 100) != 0 || fmod(year, 400) == 0);
}
static constexpr bool IsLeapYear(int32_t year) {
MOZ_ASSERT(mozilla::Abs(year) <= 2'000'000);
int32_t d = (year % 100 != 0) ? 4 : 16;
return (year & (d - 1)) == 0;
}
/**
* 21.4.1.6 DayFromYear ( y )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline double DayFromYear(double y) {
// Steps 1-7.
return 365 * (y - 1970) + floor((y - 1969) / 4.0) -
floor((y - 1901) / 100.0) + floor((y - 1601) / 400.0);
}
static constexpr int32_t DayFromYear(int32_t y) {
MOZ_ASSERT(mozilla::Abs(y) <= 2'000'000);
// Steps 1-7.
return 365 * (y - 1970) + FloorDiv((y - 1969), 4) -
FloorDiv((y - 1901), 100) + FloorDiv((y - 1601), 400);
}
/**
* 21.4.1.7 TimeFromYear ( y )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline double TimeFromYear(double y) {
return ::DayFromYear(y) * msPerDay;
}
static inline int64_t TimeFromYear(int32_t y) {
return ::DayFromYear(y) * int64_t(msPerDay);
}
/*
* This function returns the year, month and day corresponding to a given
* time value. The implementation closely follows (w.r.t. types and variable
* names) the algorithm shown in Figure 12 of [1].
*
* A key point of the algorithm is that it works on the so called
* Computational calendar where years run from March to February -- this
* largely avoids complications with leap years. The algorithm finds the
* date in the Computational calendar and then maps it to the Gregorian
* calendar.
*
* [1] Neri C, Schneider L., "Euclidean affine functions and their
* application to calendar algorithms."
* Softw Pract Exper. 2023;53(4):937-970. doi: 10.1002/spe.3172
*/
YearMonthDay js::ToYearMonthDay(int64_t time) {
// Calendar cycles repeat every 400 years in the Gregorian calendar: a
// leap day is added every 4 years, removed every 100 years and added
// every 400 years. The number of days in 400 years is cycleInDays.
constexpr uint32_t cycleInYears = 400;
constexpr uint32_t cycleInDays = cycleInYears * 365 + (cycleInYears / 4) -
(cycleInYears / 100) + (cycleInYears / 400);
static_assert(cycleInDays == 146097, "Wrong calculation of cycleInDays.");
// The natural epoch for the Computational calendar is 0000/Mar/01 and
// there are rataDie1970Jan1 = 719468 days from this date to 1970/Jan/01,
// the epoch used by ES2024, 21.4.1.1.
constexpr uint32_t rataDie1970Jan1 = 719468;
constexpr uint32_t maxU32 = std::numeric_limits<uint32_t>::max();
// Let N_U be the number of days since the 1970/Jan/01. This function sets
// N = N_U + K, where K = rataDie1970Jan1 + s * cycleInDays and s is an
// integer number (to be chosen). Then, it evaluates 4 * N + 3 on uint32_t
// operands so that N must be positive and, to prevent overflow,
// 4 * N + 3 <= maxU32 <=> N <= (maxU32 - 3) / 4.
// Therefore, we must have 0 <= N_U + K <= (maxU32 - 3) / 4 or, in other
// words, N_U must be in [minDays, maxDays] = [-K, (maxU32 - 3) / 4 - K].
// Notice that this interval moves cycleInDays positions to the left when
// s is incremented. We chose s to get the interval's mid-point as close
// as possible to 0. For this, we wish to have:
// K ~= (maxU32 - 3) / 4 - K <=> 2 * K ~= (maxU32 - 3) / 4 <=>
// K ~= (maxU32 - 3) / 8 <=>
// rataDie1970Jan1 + s * cycleInDays ~= (maxU32 - 3) / 8 <=>
// s ~= ((maxU32 - 3) / 8 - rataDie1970Jan1) / cycleInDays ~= 3669.8.
// Therefore, we chose s = 3670. The shift and correction constants
// (see [1]) are then:
constexpr uint32_t s = 3670;
constexpr uint32_t K = rataDie1970Jan1 + s * cycleInDays;
constexpr uint32_t L = s * cycleInYears;
// [minDays, maxDays] correspond to a date range from -1'468'000/Mar/01 to
// 1'471'805/Jun/05.
constexpr int32_t minDays = -int32_t(K);
constexpr int32_t maxDays = (maxU32 - 3) / 4 - K;
static_assert(minDays == -536'895'458, "Wrong calculation of minDays or K.");
static_assert(maxDays == 536'846'365, "Wrong calculation of maxDays or K.");
// These are hard limits for the algorithm and far greater than the
// range [-8.64e15, 8.64e15] required by ES2024 21.4.1.1. Callers must
// ensure this function is not called out of the hard limits and,
// preferably, not outside the ES2024 limits.
constexpr int64_t minTime = minDays * int64_t(msPerDay);
[[maybe_unused]] constexpr int64_t maxTime = maxDays * int64_t(msPerDay);
MOZ_ASSERT(minTime <= time && time <= maxTime);
// Since time is the number of milliseconds since the epoch, 1970/Jan/01,
// one might expect N_U = time / uint64_t(msPerDay) is the number of days
// since epoch. There's a catch tough. Consider, for instance, half day
// before the epoch, that is, t = -0.5 * msPerDay. This falls on
// 1969/Dec/31 and should correspond to N_U = -1 but the above gives
// N_U = 0. Indeed, t / msPerDay = -0.5 but integer division truncates
// towards 0 (C++ [expr.mul]/4) and not towards -infinity as needed, so
// that time / uint64_t(msPerDay) = 0. To workaround this issue we perform
// the division on positive operands so that truncations towards 0 and
// -infinity are equivalent. For this, set u = time - minTime, which is
// positive as asserted above. Then, perform the division u / msPerDay and
// to the result add minTime / msPerDay = minDays to cancel the
// subtraction of minTime.
const uint64_t u = uint64_t(time - minTime);
const int32_t N_U = int32_t(u / uint64_t(msPerDay)) + minDays;
MOZ_ASSERT(minDays <= N_U && N_U <= maxDays);
const uint32_t N = uint32_t(N_U) + K;
// Some magic numbers have been explained above but, unfortunately,
// others with no precise interpretation do appear. They mostly come
// from numerical approximations of Euclidean affine functions (see [1])
// which are faster for the CPU to calculate. Unfortunately, no compiler
// can do these optimizations.
// Century C and year of the century N_C:
const uint32_t N_1 = 4 * N + 3;
const uint32_t C = N_1 / 146097;
const uint32_t N_C = N_1 % 146097 / 4;
// Year of the century Z and day of the year N_Y:
const uint32_t N_2 = 4 * N_C + 3;
const uint64_t P_2 = uint64_t(2939745) * N_2;
const uint32_t Z = uint32_t(P_2 / 4294967296);
const uint32_t N_Y = uint32_t(P_2 % 4294967296) / 2939745 / 4;
// Year Y:
const uint32_t Y = 100 * C + Z;
// Month M and day D.
// The expression for N_3 has been adapted to account for the difference
// between month numbers in ES5 15.9.1.4 (from 0 to 11) and [1] (from 1
// to 12). This is done by subtracting 65536 from the original
// expression so that M decreases by 1 and so does M_G further down.
const uint32_t N_3 = 2141 * N_Y + 132377; // 132377 = 197913 - 65536
const uint32_t M = N_3 / 65536;
const uint32_t D = N_3 % 65536 / 2141;
// Map from Computational to Gregorian calendar. Notice also the year
// correction and the type change and that Jan/01 is day 306 of the
// Computational calendar, cf. Table 1. [1]
constexpr uint32_t daysFromMar01ToJan01 = 306;
const uint32_t J = N_Y >= daysFromMar01ToJan01;
const int32_t Y_G = int32_t((Y - L) + J);
const int32_t M_G = int32_t(J ? M - 12 : M);
const int32_t D_G = int32_t(D + 1);
return {Y_G, M_G, D_G};
}
/**
* 21.4.1.8 YearFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t YearFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return ToYearMonthDay(t).year;
}
/**
* 21.4.1.9 DayWithinYear ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static double DayWithinYear(int64_t t, double year) {
MOZ_ASSERT(::YearFromTime(t) == year);
return Day(t) - ::DayFromYear(year);
}
/**
* 21.4.1.11 MonthFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t MonthFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return ToYearMonthDay(t).month;
}
/**
* 21.4.1.12 DateFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t DateFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return ToYearMonthDay(t).day;
}
/**
* 21.4.1.13 WeekDay ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t WeekDay(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
int32_t result = (Day(t) + 4) % 7;
if (result < 0) {
result += 7;
}
return result;
}
static inline int DayFromMonth(int month, bool isLeapYear) {
/*
* The following array contains the day of year for the first day of
* each month, where index 0 is January, and day 0 is January 1.
*/
static const int firstDayOfMonth[2][13] = {
{0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
{0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}};
MOZ_ASSERT(0 <= month && month <= 12);
return firstDayOfMonth[isLeapYear][month];
}
template <typename T>
static inline int DayFromMonth(T month, bool isLeapYear) = delete;
/**
* 21.4.1.28 MakeDay ( year, month, date )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static double MakeDay(double year, double month, double date) {
// Step 1.
if (!std::isfinite(year) || !std::isfinite(month) || !std::isfinite(date)) {
return GenericNaN();
}
// Steps 2-4.
double y = ToInteger(year);
double m = ToInteger(month);
double dt = ToInteger(date);
static constexpr int32_t maxYears = 1'000'000;
static constexpr int32_t maxMonths = 1'000'000 * 12;
static constexpr int32_t maxDate = 100'000'000;
// Use integer math if possible, because it avoids some notoriously slow
// functions like `fmod`.
if (MOZ_LIKELY(std::abs(y) <= maxYears && std::abs(m) <= maxMonths &&
std::abs(dt) <= maxDate)) {
int32_t year = mozilla::AssertedCast<int32_t>(y);
int32_t month = mozilla::AssertedCast<int32_t>(m);
int32_t date = mozilla::AssertedCast<int32_t>(dt);
static_assert(maxMonths % 12 == 0,
"maxYearMonths expects maxMonths is divisible by 12");
static constexpr int32_t maxYearMonths = maxYears + (maxMonths / 12);
static constexpr int32_t maxYearDay = DayFromYear(maxYearMonths);
static constexpr int32_t minYearDay = DayFromYear(-maxYearMonths);
static constexpr int32_t daysInLeapYear = 366;
static constexpr int32_t maxDay = maxYearDay + daysInLeapYear + maxDate;
static constexpr int32_t minDay = minYearDay + daysInLeapYear - maxDate;
static_assert(maxYearMonths == 2'000'000);
static_assert(maxYearDay == 729'765'472);
static_assert(minYearDay == -731'204'528);
static_assert(maxDay == maxYearDay + daysInLeapYear + maxDate);
static_assert(minDay == minYearDay + daysInLeapYear - maxDate);
// Step 5.
int32_t ym = year + FloorDiv(month, 12);
MOZ_ASSERT(std::abs(ym) <= maxYearMonths);
// Step 6. (Implicit)
// Step 7.
int32_t mn = PositiveModulo(month, 12);
// Step 8.
bool leap = IsLeapYear(ym);
int32_t yearday = ::DayFromYear(ym);
int32_t monthday = DayFromMonth(mn, leap);
MOZ_ASSERT(minYearDay <= yearday && yearday <= maxYearDay);
// Step 9.
int32_t day = yearday + monthday + date - 1;
MOZ_ASSERT(minDay <= day && day <= maxDay);
return day;
}
// Step 5.
double ym = y + floor(m / 12);
// Step 6.
if (!std::isfinite(ym)) {
return GenericNaN();
}
// Step 7.
int mn = int(PositiveModulo(m, 12));
// Step 8.
bool leap = IsLeapYear(ym);
double yearday = floor(TimeFromYear(ym) / msPerDay);
double monthday = DayFromMonth(mn, leap);
// Step 9.
return yearday + monthday + dt - 1;
}
/**
* 21.4.1.29 MakeDate ( day, time )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static inline double MakeDate(double day, double time) {
// Step 1.
if (!std::isfinite(day) || !std::isfinite(time)) {
return GenericNaN();
}
// Steps 2-4.
return day * msPerDay + time;
}
JS_PUBLIC_API double JS::MakeDate(double year, unsigned month, unsigned day) {
MOZ_ASSERT(month <= 11);
MOZ_ASSERT(day >= 1 && day <= 31);
return ::MakeDate(MakeDay(year, month, day), 0);
}
JS_PUBLIC_API double JS::MakeDate(double year, unsigned month, unsigned day,
double time) {
MOZ_ASSERT(month <= 11);
MOZ_ASSERT(day >= 1 && day <= 31);
return ::MakeDate(MakeDay(year, month, day), time);
}
JS_PUBLIC_API double JS::YearFromTime(double time) {
const auto clipped = TimeClip(time);
if (!clipped.isValid()) {
return GenericNaN();
}
int64_t tv;
MOZ_ALWAYS_TRUE(mozilla::NumberEqualsInt64(clipped.toDouble(), &tv));
return ::YearFromTime(tv);
}
JS_PUBLIC_API double JS::MonthFromTime(double time) {
const auto clipped = TimeClip(time);
if (!clipped.isValid()) {
return GenericNaN();
}
int64_t tv;
MOZ_ALWAYS_TRUE(mozilla::NumberEqualsInt64(clipped.toDouble(), &tv));
return ::MonthFromTime(tv);
}
JS_PUBLIC_API double JS::DayFromTime(double time) {
const auto clipped = TimeClip(time);
if (!clipped.isValid()) {
return GenericNaN();
}
int64_t tv;
MOZ_ALWAYS_TRUE(mozilla::NumberEqualsInt64(clipped.toDouble(), &tv));
return DateFromTime(tv);
}
JS_PUBLIC_API double JS::DayFromYear(double year) {
return ::DayFromYear(year);
}
JS_PUBLIC_API double JS::DayWithinYear(double time, double year) {
const auto clipped = TimeClip(time);
if (!clipped.isValid()) {
return GenericNaN();
}
int64_t tv;
MOZ_ALWAYS_TRUE(mozilla::NumberEqualsInt64(clipped.toDouble(), &tv));
return ::DayWithinYear(tv, year);
}
JS_PUBLIC_API void JS::SetReduceMicrosecondTimePrecisionCallback(
JS::ReduceMicrosecondTimePrecisionCallback callback) {
sReduceMicrosecondTimePrecisionCallback = callback;
}
JS_PUBLIC_API JS::ReduceMicrosecondTimePrecisionCallback
JS::GetReduceMicrosecondTimePrecisionCallback() {
return sReduceMicrosecondTimePrecisionCallback;
}
JS_PUBLIC_API void JS::SetTimeResolutionUsec(uint32_t resolution, bool jitter) {
sResolutionUsec = resolution;
sJitter = jitter;
}
#if JS_HAS_INTL_API
int32_t DateTimeHelper::getTimeZoneOffset(DateTimeInfo::ForceUTC forceUTC,
int64_t epochMilliseconds,
DateTimeInfo::TimeZoneOffset offset) {
MOZ_ASSERT_IF(offset == DateTimeInfo::TimeZoneOffset::UTC,
IsTimeValue(epochMilliseconds));
MOZ_ASSERT_IF(offset == DateTimeInfo::TimeZoneOffset::Local,
IsLocalTimeValue(epochMilliseconds));
return DateTimeInfo::getOffsetMilliseconds(forceUTC, epochMilliseconds,
offset);
}
#else
/*
* Find a year for which any given date will fall on the same weekday.
*
* This function should be used with caution when used other than
* for determining DST; it hasn't been proven not to produce an
* incorrect year for times near year boundaries.
*/
int DateTimeHelper::equivalentYearForDST(int year) {
/*
* Years and leap years on which Jan 1 is a Sunday, Monday, etc.
*
* yearStartingWith[0][i] is an example non-leap year where
* Jan 1 appears on Sunday (i == 0), Monday (i == 1), etc.
*
* yearStartingWith[1][i] is an example leap year where
* Jan 1 appears on Sunday (i == 0), Monday (i == 1), etc.
*
* Keep two different mappings, one for past years (< 1970), and a
* different one for future years (> 2037).
*/
static const int pastYearStartingWith[2][7] = {
{1978, 1973, 1974, 1975, 1981, 1971, 1977},
{1984, 1996, 1980, 1992, 1976, 1988, 1972}};
static const int futureYearStartingWith[2][7] = {
{2034, 2035, 2030, 2031, 2037, 2027, 2033},
{2012, 2024, 2036, 2020, 2032, 2016, 2028}};
int day = int(::DayFromYear(year) + 4) % 7;
if (day < 0) {
day += 7;
}
const auto& yearStartingWith =
year < 1970 ? pastYearStartingWith : futureYearStartingWith;
return yearStartingWith[IsLeapYear(year)][day];
}
// Return true if |t| is representable as a 32-bit time_t variable, that means
// the year is in [1970, 2038).
bool DateTimeHelper::isRepresentableAsTime32(int64_t t) {
return 0 <= t && t < 2145916800000;
}
/* ES5 15.9.1.8. */
int32_t DateTimeHelper::daylightSavingTA(DateTimeInfo::ForceUTC forceUTC,
int64_t t) {
/*
* If earlier than 1970 or after 2038, potentially beyond the ken of
* many OSes, map it to an equivalent year before asking.
*/
if (!isRepresentableAsTime32(t)) {
auto [year, month, day] = ToYearMonthDay(t);
int equivalentYear = equivalentYearForDST(year);
double equivalentDay = MakeDay(equivalentYear, month, day);
double equivalentDate = MakeDate(equivalentDay, TimeWithinDay(t));
MOZ_ALWAYS_TRUE(mozilla::NumberEqualsInt64(equivalentDate, &t));
}
return DateTimeInfo::getDSTOffsetMilliseconds(forceUTC, t);
}
int32_t DateTimeHelper::adjustTime(DateTimeInfo::ForceUTC forceUTC,
int64_t date) {
int32_t localTZA = DateTimeInfo::localTZA(forceUTC);
int32_t t = daylightSavingTA(forceUTC, date) + localTZA;
return (localTZA >= 0) ? (t % msPerDay) : -((msPerDay - t) % msPerDay);
}
int32_t DateTimeHelper::getTimeZoneOffset(DateTimeInfo::ForceUTC forceUTC,
int64_t epochMilliseconds,
DateTimeInfo::TimeZoneOffset offset) {
MOZ_ASSERT_IF(offset == DateTimeInfo::TimeZoneOffset::UTC,
IsTimeValue(epochMilliseconds));
MOZ_ASSERT_IF(offset == DateTimeInfo::TimeZoneOffset::Local,
IsLocalTimeValue(epochMilliseconds));
if (offset == DateTimeInfo::TimeZoneOffset::UTC) {
return adjustTime(forceUTC, epochMilliseconds);
}
// Following the ES2017 specification creates undesirable results at DST
// transitions. For example when transitioning from PST to PDT,
// |new Date(2016,2,13,2,0,0).toTimeString()| returns the string value
// "01:00:00 GMT-0800 (PST)" instead of "03:00:00 GMT-0700 (PDT)". Follow
// V8 and subtract one hour before computing the offset.
return adjustTime(forceUTC, epochMilliseconds -
int64_t(DateTimeInfo::localTZA(forceUTC)) -
int64_t(msPerHour));
}
#endif /* JS_HAS_INTL_API */
/**
* 21.4.1.25 LocalTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int64_t LocalTime(DateTimeInfo::ForceUTC forceUTC, double t) {
MOZ_ASSERT(std::isfinite(t));
MOZ_ASSERT(IsTimeValue(t));
// Steps 1-4.
int32_t offsetMs = DateTimeHelper::getTimeZoneOffset(
forceUTC, static_cast<int64_t>(t), DateTimeInfo::TimeZoneOffset::UTC);
MOZ_ASSERT(std::abs(offsetMs) < msPerDay);
// Step 5.
return static_cast<int64_t>(t) + offsetMs;
}
/**
* 21.4.1.26 UTC ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static double UTC(DateTimeInfo::ForceUTC forceUTC, double t) {
// Step 1.
if (!std::isfinite(t)) {
return GenericNaN();
}
// Return early when |t| is outside the valid local time value limits.
if (!IsLocalTimeValue(t)) {
return GenericNaN();
}
// Steps 2-5.
int32_t offsetMs = DateTimeHelper::getTimeZoneOffset(
forceUTC, static_cast<int64_t>(t), DateTimeInfo::TimeZoneOffset::Local);
MOZ_ASSERT(std::abs(offsetMs) < msPerDay);
// Step 6.
return static_cast<double>(static_cast<int64_t>(t) - offsetMs);
}
/**
* 21.4.1.14 HourFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t HourFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return PositiveModulo(FloorDiv(t, msPerHour), HoursPerDay);
}
/**
* 21.4.1.15 MinFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t MinFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return PositiveModulo(FloorDiv(t, msPerMinute), MinutesPerHour);
}
/**
* 21.4.1.16 SecFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t SecFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return PositiveModulo(FloorDiv(t, msPerSecond), SecondsPerMinute);
}
/**
* 21.4.1.17 msFromTime ( t )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static int32_t msFromTime(int64_t t) {
MOZ_ASSERT(IsLocalTimeValue(t));
return PositiveModulo(t, msPerSecond);
}
HourMinuteSecond js::ToHourMinuteSecond(int64_t epochMilliseconds) {
MOZ_ASSERT(IsLocalTimeValue(epochMilliseconds));
int32_t hour = HourFromTime(epochMilliseconds);
MOZ_ASSERT(0 <= hour && hour < HoursPerDay);
int32_t minute = MinFromTime(epochMilliseconds);
MOZ_ASSERT(0 <= minute && minute < MinutesPerHour);
int32_t second = SecFromTime(epochMilliseconds);
MOZ_ASSERT(0 <= minute && minute < SecondsPerMinute);
return {hour, minute, second};
}
/**
* 21.4.1.27 MakeTime ( hour, min, sec, ms )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static double MakeTime(double hour, double min, double sec, double ms) {
// Step 1.
if (!std::isfinite(hour) || !std::isfinite(min) || !std::isfinite(sec) ||
!std::isfinite(ms)) {
return GenericNaN();
}
// Step 2.
double h = ToInteger(hour);
// Step 3.
double m = ToInteger(min);
// Step 4.
double s = ToInteger(sec);
// Step 5.
double milli = ToInteger(ms);
// Step 6.
return h * msPerHour + m * msPerMinute + s * msPerSecond + milli;
}
/**
* 21.4.1.30 MakeFullYear ( year )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static double MakeFullYear(double year) {
// Step 1.
if (std::isnan(year)) {
return year;
}
// Step 2.
double truncated = ToInteger(year);
// Step 3.
if (0 <= truncated && truncated <= 99) {
return 1900 + truncated;
}
// Step 4.
return truncated;
}
/**
* end of ECMA 'support' functions
*/
/**
* 21.4.3.4 Date.UTC ( year [ , month [ , date [ , hours [ , minutes [ , seconds
* [ , ms ] ] ] ] ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_UTC(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date", "UTC");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1.
double y;
if (!ToNumber(cx, args.get(0), &y)) {
return false;
}
// Step 2.
double m;
if (args.length() >= 2) {
if (!ToNumber(cx, args[1], &m)) {
return false;
}
} else {
m = 0;
}
// Step 3.
double dt;
if (args.length() >= 3) {
if (!ToNumber(cx, args[2], &dt)) {
return false;
}
} else {
dt = 1;
}
// Step 4.
double h;
if (args.length() >= 4) {
if (!ToNumber(cx, args[3], &h)) {
return false;
}
} else {
h = 0;
}
// Step 5.
double min;
if (args.length() >= 5) {
if (!ToNumber(cx, args[4], &min)) {
return false;
}
} else {
min = 0;
}
// Step 6.
double s;
if (args.length() >= 6) {
if (!ToNumber(cx, args[5], &s)) {
return false;
}
} else {
s = 0;
}
// Step 7.
double milli;
if (args.length() >= 7) {
if (!ToNumber(cx, args[6], &milli)) {
return false;
}
} else {
milli = 0;
}
// Step 8.
double yr = MakeFullYear(y);
// Step 9.
ClippedTime time =
TimeClip(MakeDate(MakeDay(yr, m, dt), MakeTime(h, min, s, milli)));
args.rval().set(TimeValue(time));
return true;
}
/*
* Read and convert decimal digits from s[*i] into *result
* while *i < limit.
*
* Succeed if any digits are converted. Advance *i only
* as digits are consumed.
*/
template <typename CharT>
static bool ParseDigits(size_t* result, const CharT* s, size_t* i,
size_t limit) {
size_t init = *i;
*result = 0;
while (*i < limit && ('0' <= s[*i] && s[*i] <= '9')) {
*result *= 10;
*result += (s[*i] - '0');
++(*i);
}
return *i != init;
}
/*
* Read and convert decimal digits to the right of a decimal point,
* representing a fractional integer, from s[*i] into *result
* while *i < limit, up to 3 digits. Consumes any digits beyond 3
* without affecting the result.
*
* Succeed if any digits are converted. Advance *i only
* as digits are consumed.
*/
template <typename CharT>
static bool ParseFractional(int* result, const CharT* s, size_t* i,
size_t limit) {
int factor = 100;
size_t init = *i;
*result = 0;
for (; *i < limit && ('0' <= s[*i] && s[*i] <= '9'); ++(*i)) {
if (*i - init >= 3) {
// If we're past 3 digits, do nothing with it, but continue to
// consume the remainder of the digits
continue;
}
*result += (s[*i] - '0') * factor;
factor /= 10;
}
return *i != init;
}
/*
* Read and convert exactly n decimal digits from s[*i]
* to s[min(*i+n,limit)] into *result.
*
* Succeed if exactly n digits are converted. Advance *i only
* on success.
*/
template <typename CharT>
static bool ParseDigitsN(size_t n, size_t* result, const CharT* s, size_t* i,
size_t limit) {
size_t init = *i;
if (ParseDigits(result, s, i, std::min(limit, init + n))) {
return (*i - init) == n;
}
*i = init;
return false;
}
/*
* Read and convert n or less decimal digits from s[*i]
* to s[min(*i+n,limit)] into *result.
*
* Succeed only if greater than zero but less than or equal to n digits are
* converted. Advance *i only on success.
*/
template <typename CharT>
static bool ParseDigitsNOrLess(size_t n, size_t* result, const CharT* s,
size_t* i, size_t limit) {
size_t init = *i;
if (ParseDigits(result, s, i, std::min(limit, init + n))) {
return ((*i - init) > 0) && ((*i - init) <= n);
}
*i = init;
return false;
}
/*
* Parse a string according to the formats specified in the standard:
*
*
* These formats are based upon a simplification of the ISO 8601 Extended
* Format. As per the spec omitted month and day values are defaulted to '01',
* omitted HH:mm:ss values are defaulted to '00' and an omitted sss field is
* defaulted to '000'.
*
* For cross compatibility we allow the following extensions.
*
* These are:
*
* One or more decimal digits for milliseconds:
* The specification requires exactly three decimal digits for
* the fractional part but we allow for one or more digits.
*
* Time zone specifier without ':':
* We allow the time zone to be specified without a ':' character.
* E.g. "T19:00:00+0700" is equivalent to "T19:00:00+07:00".
*
* Date part:
*
* Year:
* YYYY (eg 1997)
*
* Year and month:
* YYYY-MM (eg 1997-07)
*
* Complete date:
* YYYY-MM-DD (eg 1997-07-16)
*
* Time part:
*
* Hours and minutes:
* Thh:mmTZD (eg T19:20+01:00)
*
* Hours, minutes and seconds:
* Thh:mm:ssTZD (eg T19:20:30+01:00)
*
* Hours, minutes, seconds and a decimal fraction of a second:
* Thh:mm:ss.sssTZD (eg T19:20:30.45+01:00)
*
* where:
*
* YYYY = four-digit year or six digit year as +YYYYYY or -YYYYYY
* MM = two-digit month (01=January, etc.)
* DD = two-digit day of month (01 through 31)
* hh = two digits of hour (00 through 24) (am/pm NOT allowed)
* mm = two digits of minute (00 through 59)
* ss = two digits of second (00 through 59)
* sss = one or more digits representing a decimal fraction of a second
* TZD = time zone designator (Z or +hh:mm or -hh:mm or missing for local)
*/
template <typename CharT>
static bool ParseISOStyleDate(DateTimeInfo::ForceUTC forceUTC, const CharT* s,
size_t length, ClippedTime* result) {
size_t i = 0;
int tzMul = 1;
int dateMul = 1;
size_t year = 1970;
size_t month = 1;
size_t day = 1;
size_t hour = 0;
size_t min = 0;
size_t sec = 0;
int msec = 0;
bool isLocalTime = false;
size_t tzHour = 0;
size_t tzMin = 0;
#define PEEK(ch) (i < length && s[i] == ch)
#define NEED(ch) \
if (i >= length || s[i] != ch) { \
return false; \
} else { \
++i; \
}
#define DONE_DATE_UNLESS(ch) \
if (i >= length || s[i] != ch) { \
goto done_date; \
} else { \
++i; \
}
#define DONE_UNLESS(ch) \
if (i >= length || s[i] != ch) { \
goto done; \
} else { \
++i; \
}
#define NEED_NDIGITS(n, field) \
if (!ParseDigitsN(n, &field, s, &i, length)) { \
return false; \
}
if (PEEK('+') || PEEK('-')) {
if (PEEK('-')) {
dateMul = -1;
}
++i;
NEED_NDIGITS(6, year);
// -000000 is not a valid expanded year.
if (year == 0 && dateMul == -1) {
return false;
}
} else {
NEED_NDIGITS(4, year);
}
DONE_DATE_UNLESS('-');
NEED_NDIGITS(2, month);
DONE_DATE_UNLESS('-');
NEED_NDIGITS(2, day);
done_date:
if (PEEK('T')) {
++i;
} else {
goto done;
}
NEED_NDIGITS(2, hour);
NEED(':');
NEED_NDIGITS(2, min);
if (PEEK(':')) {
++i;
NEED_NDIGITS(2, sec);
if (PEEK('.')) {
++i;
if (!ParseFractional(&msec, s, &i, length)) {
return false;
}
}
}
if (PEEK('Z')) {
++i;
} else if (PEEK('+') || PEEK('-')) {
if (PEEK('-')) {
tzMul = -1;
}
++i;
NEED_NDIGITS(2, tzHour);
/*
* Non-standard extension to the ISO date format (permitted by ES5):
* allow "-0700" as a time zone offset, not just "-07:00".
*/
if (PEEK(':')) {
++i;
}
NEED_NDIGITS(2, tzMin);
} else {
isLocalTime = true;
}
done:
if (year > 275943 // ceil(1e8/365) + 1970
|| month == 0 || month > 12 || day == 0 || day > 31 || hour > 24 ||
(hour == 24 && (min > 0 || sec > 0 || msec > 0)) || min > 59 ||
sec > 59 || tzHour > 23 || tzMin > 59) {
return false;
}
if (i != length) {
return false;
}
month -= 1; /* convert month to 0-based */
double date = MakeDate(MakeDay(dateMul * int32_t(year), month, day),
MakeTime(hour, min, sec, msec));
if (isLocalTime) {
date = UTC(forceUTC, date);
} else {
date -=
tzMul * (int32_t(tzHour) * msPerHour + int32_t(tzMin) * msPerMinute);
}
*result = TimeClip(date);
return NumbersAreIdentical(date, result->toDouble());
#undef PEEK
#undef NEED
#undef DONE_UNLESS
#undef NEED_NDIGITS
}
/**
* Non-ISO years < 100 get fixed up, to allow 2-digit year formats.
* year < 50 becomes 2000-2049, 50-99 becomes 1950-1999.
*/
static int FixupYear(int year) {
if (year < 50) {
year += 2000;
} else if (year >= 50 && year < 100) {
year += 1900;
}
return year;
}
template <typename CharT>
static bool MatchesKeyword(const CharT* s, size_t len, const char* keyword) {
while (len > 0) {
MOZ_ASSERT(IsAsciiAlpha(*s));
MOZ_ASSERT(IsAsciiLowercaseAlpha(*keyword) || *keyword == '\0');
if (unicode::ToLowerCase(static_cast<Latin1Char>(*s)) != *keyword) {
return false;
}
++s, ++keyword;
--len;
}
return *keyword == '\0';
}
static constexpr const char* const month_prefixes[] = {
"jan", "feb", "mar", "apr", "may", "jun",
"jul", "aug", "sep", "oct", "nov", "dec",
};
/**
* Given a string s of length >= 3, checks if it begins,
* case-insensitive, with the given lower case prefix.
*/
template <typename CharT>
static bool StartsWithMonthPrefix(const CharT* s, const char* prefix) {
MOZ_ASSERT(strlen(prefix) == 3);
for (size_t i = 0; i < 3; ++i) {
MOZ_ASSERT(IsAsciiAlpha(*s));
MOZ_ASSERT(IsAsciiLowercaseAlpha(*prefix));
if (unicode::ToLowerCase(static_cast<Latin1Char>(*s)) != *prefix) {
return false;
}
++s, ++prefix;
}
return true;
}
template <typename CharT>
static bool IsMonthName(const CharT* s, size_t len, int* mon) {
// Month abbreviations < 3 chars are not accepted.
if (len < 3) {
return false;
}
for (size_t m = 0; m < std::size(month_prefixes); ++m) {
if (StartsWithMonthPrefix(s, month_prefixes[m])) {
// Use numeric value.
*mon = m + 1;
return true;
}
}
return false;
}
/*
* Try to parse the following date formats:
* dd-MMM-yyyy
* dd-MMM-yy
* MMM-dd-yyyy
* MMM-dd-yy
* yyyy-MMM-dd
* yy-MMM-dd
*
* Returns true and fills all out parameters when successfully parsed
* dashed-date. Otherwise returns false and leaves out parameters untouched.
*/
template <typename CharT>
static bool TryParseDashedDatePrefix(const CharT* s, size_t length,
size_t* indexOut, int* yearOut,
int* monOut, int* mdayOut) {
size_t i = *indexOut;
size_t pre = i;
size_t mday;
if (!ParseDigitsNOrLess(6, &mday, s, &i, length)) {
return false;
}
size_t mdayDigits = i - pre;
if (i >= length || s[i] != '-') {
return false;
}
++i;
int mon = 0;
if (*monOut == -1) {
// If month wasn't already set by ParseDate, it must be in the middle of
// this format, let's look for it
size_t start = i;
for (; i < length; i++) {
if (!IsAsciiAlpha(s[i])) {
break;
}
}
if (!IsMonthName(s + start, i - start, &mon)) {
return false;
}
if (i >= length || s[i] != '-') {
return false;
}
++i;
}
pre = i;
size_t year;
if (!ParseDigitsNOrLess(6, &year, s, &i, length)) {
return false;
}
size_t yearDigits = i - pre;
if (i < length && IsAsciiDigit(s[i])) {
return false;
}
// Swap the mday and year if the year wasn't specified in full.
if (mday > 31 && year <= 31 && yearDigits < 4) {
std::swap(mday, year);
std::swap(mdayDigits, yearDigits);
}
if (mday > 31 || mdayDigits > 2) {
return false;
}
year = FixupYear(year);
*indexOut = i;
*yearOut = year;
if (*monOut == -1) {
*monOut = mon;
}
*mdayOut = mday;
return true;
}
/*
* Try to parse dates in the style of YYYY-MM-DD which do not conform to
* the formal standard from ParseISOStyleDate. This includes cases such as
*
* - Year does not have 4 digits
* - Month or mday has 1 digit
* - Space in between date and time, rather than a 'T'
*
* Regarding the last case, this function only parses out the date, returning
* to ParseDate to finish parsing the time and timezone, if present.
*
* Returns true and fills all out parameters when successfully parsed
* dashed-date. Otherwise returns false and leaves out parameters untouched.
*/
template <typename CharT>
static bool TryParseDashedNumericDatePrefix(const CharT* s, size_t length,
size_t* indexOut, int* yearOut,
int* monOut, int* mdayOut) {
size_t i = *indexOut;
size_t first;
if (!ParseDigitsNOrLess(6, &first, s, &i, length)) {
return false;
}
if (i >= length || s[i] != '-') {
return false;
}
++i;
size_t second;
if (!ParseDigitsNOrLess(2, &second, s, &i, length)) {
return false;
}
if (i >= length || s[i] != '-') {
return false;
}
++i;
size_t third;
if (!ParseDigitsNOrLess(6, &third, s, &i, length)) {
return false;
}
int year;
int mon = -1;
int mday = -1;
// 1 or 2 digits for the first number is tricky; 1-12 means it's a month, 0 or
// >31 means it's a year, and 13-31 is invalid due to ambiguity.
if (first >= 1 && first <= 12) {
mon = first;
} else if (first == 0 || first > 31) {
year = first;
} else {
return false;
}
if (mon < 0) {
// If month hasn't been set yet, it's definitely the 2nd number
mon = second;
} else {
// If it has, the next number is the mday
mday = second;
}
if (mday < 0) {
// The third number is probably the mday...
mday = third;
} else {
// But otherwise, it's the year
year = third;
}
if (mon < 1 || mon > 12 || mday < 1 || mday > 31) {
return false;
}
year = FixupYear(year);
*indexOut = i;
*yearOut = year;
*monOut = mon;
*mdayOut = mday;
return true;
}
struct CharsAndAction {
const char* chars;
int action;
};
static constexpr CharsAndAction keywords[] = {
// clang-format off
// AM/PM
{ "am", -1 },
{ "pm", -2 },
// Time zone abbreviations.
{ "gmt", 10000 + 0 },
{ "z", 10000 + 0 },
{ "ut", 10000 + 0 },
{ "utc", 10000 + 0 },
{ "est", 10000 + 5 * 60 },
{ "edt", 10000 + 4 * 60 },
{ "cst", 10000 + 6 * 60 },
{ "cdt", 10000 + 5 * 60 },
{ "mst", 10000 + 7 * 60 },
{ "mdt", 10000 + 6 * 60 },
{ "pst", 10000 + 8 * 60 },
{ "pdt", 10000 + 7 * 60 },
// clang-format on
};
template <size_t N>
static constexpr size_t MinKeywordLength(const CharsAndAction (&keywords)[N]) {
size_t min = size_t(-1);
for (const CharsAndAction& keyword : keywords) {
min = std::min(min, std::char_traits<char>::length(keyword.chars));
}
return min;
}
template <typename CharT>
static bool ParseDate(DateTimeInfo::ForceUTC forceUTC, const CharT* s,
size_t length, ClippedTime* result) {
if (length == 0) {
return false;
}
if (ParseISOStyleDate(forceUTC, s, length, result)) {
return true;
}
size_t index = 0;
int mon = -1;
bool seenMonthName = false;
// Before we begin, we need to scrub any words from the beginning of the
// string up to the first number, recording the month if we encounter it
for (; index < length; index++) {
int c = s[index];
if (strchr(" ,.-/", c)) {
continue;
}
if (!IsAsciiAlpha(c)) {
break;
}
size_t start = index;
index++;
for (; index < length; index++) {
if (!IsAsciiAlpha(s[index])) {
break;
}
}
if (index >= length) {
return false;
}
if (IsMonthName(s + start, index - start, &mon)) {
seenMonthName = true;
// If the next digit is a number, we need to break so it
// gets parsed as mday
if (IsAsciiDigit(s[index])) {
break;
}
} else if (!strchr(" ,.-/", s[index])) {
// We're only allowing the above delimiters after the day of
// week to prevent things such as "foo_1" from being parsed
// as a date, which may break software which uses this function
// to determine whether or not something is a date.
return false;
}
}
int year = -1;
int mday = -1;
int hour = -1;
int min = -1;
int sec = -1;
int msec = 0;
int tzOffset = -1;
// One of '+', '-', ':', '/', or 0 (the default value).
int prevc = 0;
bool seenPlusMinus = false;
bool seenFullYear = false;
bool negativeYear = false;
// Includes "GMT", "UTC", "UT", and "Z" timezone keywords
bool seenGmtAbbr = false;
// Try parsing the leading dashed-date.
//
// If successfully parsed, index is updated to the end of the date part,
// and year, mon, mday are set to the date.
// Continue parsing optional time + tzOffset parts.
//
// Otherwise, this is no-op.
bool isDashedDate =
TryParseDashedDatePrefix(s, length, &index, &year, &mon, &mday) ||
TryParseDashedNumericDatePrefix(s, length, &index, &year, &mon, &mday);
if (isDashedDate && index < length && strchr("T:+", s[index])) {
return false;
}
while (index < length) {
int c = s[index];
index++;
// Normalize U+202F (NARROW NO-BREAK SPACE). This character appears between
// the AM/PM markers for |date.toLocaleString("en")|. We have to normalize
// it for backward compatibility reasons.
if (c == 0x202F) {
c = ' ';
}
if ((c == '+' || c == '-') &&
// Reject + or - after timezone (still allowing for negative year)
((seenPlusMinus && year != -1) ||
// Reject timezones like "1995-09-26 -04:30" (if the - is right up
// against the previous number, it will get parsed as a time,
// see the other comment below)
(year != -1 && hour == -1 && !seenGmtAbbr &&
!IsAsciiDigit(s[index - 2])))) {
return false;
}
// Spaces, ASCII control characters, periods, and commas are simply ignored.
if (c <= ' ' || c == '.' || c == ',') {
continue;
}
// Parse delimiter characters. Save them to the side for future use.
if (c == '/' || c == ':' || c == '+') {
prevc = c;
continue;
}
// Dashes are delimiters if they're immediately followed by a number field.
// If they're not followed by a number field, they're simply ignored.
if (c == '-') {
if (index < length && IsAsciiDigit(s[index])) {
prevc = c;
}
continue;
}
// Skip over comments -- text inside matching parentheses. (Comments
// themselves may contain comments as long as all the parentheses properly
// match up. And apparently comments, including nested ones, may validly be
// terminated by end of input...)
if (c == '(') {
int depth = 1;
while (index < length) {
c = s[index];
index++;
if (c == '(') {
depth++;
} else if (c == ')') {
if (--depth <= 0) {
break;
}
}
}
continue;
}
// Parse a number field.
if (IsAsciiDigit(c)) {
size_t partStart = index - 1;
uint32_t u = c - '0';
while (index < length) {
c = s[index];
if (!IsAsciiDigit(c)) {
break;
}
u = u * 10 + (c - '0');
index++;
}
size_t partLength = index - partStart;
// See above for why we have to normalize U+202F.
if (c == 0x202F) {
c = ' ';
}
int n = int(u);
/*
* Allow TZA before the year, so 'Wed Nov 05 21:49:11 GMT-0800 1997'
* works.
*
* Uses of seenPlusMinus allow ':' in TZA, so Java no-timezone style
* of GMT+4:30 works.
*/
if (prevc == '-' && (tzOffset != 0 || seenPlusMinus) && partLength >= 4 &&
year < 0) {
// Parse as a negative, possibly zero-padded year if
// 1. the preceding character is '-',
// 2. the TZA is not 'GMT' (tested by |tzOffset != 0|),
// 3. or a TZA was already parsed |seenPlusMinus == true|,
// 4. the part length is at least 4 (to parse '-08' as a TZA),
// 5. and we did not already parse a year |year < 0|.
year = n;
seenFullYear = true;
negativeYear = true;
} else if ((prevc == '+' || prevc == '-') &&
// "1995-09-26-04:30" needs to be parsed as a time,
// not a time zone
(seenGmtAbbr || hour != -1)) {
/* Make ':' case below change tzOffset. */
seenPlusMinus = true;
/* offset */
if (n < 24 && partLength <= 2) {
n = n * 60; /* EG. "GMT-3" */
} else {
n = n % 100 + n / 100 * 60; /* eg "GMT-0430" */
}
if (prevc == '+') /* plus means east of GMT */
n = -n;
// Reject if not preceded by 'GMT' or if a time zone offset
// was already parsed.
if (tzOffset != 0 && tzOffset != -1) {
return false;
}
tzOffset = n;
} else if (prevc == '/' && mon >= 0 && mday >= 0 && year < 0) {
if (c <= ' ' || c == ',' || c == '/' || index >= length) {
year = n;
} else {
return false;
}
} else if (c == ':') {
if (hour < 0) {
hour = /*byte*/ n;
} else if (min < 0) {
min = /*byte*/ n;
} else {
return false;
}
} else if (c == '/') {
/*
* Until it is determined that mon is the actual month, keep
* it as 1-based rather than 0-based.
*/
if (mon < 0) {
mon = /*byte*/ n;
} else if (mday < 0) {
mday = /*byte*/ n;
} else {
return false;
}
} else if (index < length && c != ',' && c > ' ' && c != '-' &&
c != '(' &&
// Allow '.' as a delimiter until seconds have been parsed
// (this allows the decimal for milliseconds)
(c != '.' || sec != -1) &&
// Allow zulu time e.g. "09/26/1995 16:00Z", or
// '+' directly after time e.g. 00:00+0500
!(hour != -1 && strchr("Zz+", c)) &&
// Allow month or AM/PM directly after a number
(!IsAsciiAlpha(c) ||
(mon != -1 && !(strchr("AaPp", c) && index < length - 1 &&
strchr("Mm", s[index + 1]))))) {
return false;
} else if (seenPlusMinus && n < 60) { /* handle GMT-3:30 */
if (tzOffset < 0) {
tzOffset -= n;
} else {
tzOffset += n;
}
} else if (hour >= 0 && min < 0) {
min = /*byte*/ n;
} else if (prevc == ':' && min >= 0 && sec < 0) {
sec = /*byte*/ n;
if (c == '.') {
index++;
if (!ParseFractional(&msec, s, &index, length)) {
return false;
}
}
} else if (mon < 0) {
mon = /*byte*/ n;
} else if (mon >= 0 && mday < 0) {
mday = /*byte*/ n;
} else if (mon >= 0 && mday >= 0 && year < 0) {
year = n;
seenFullYear = partLength >= 4;
} else {
return false;
}
prevc = 0;
continue;
}
// Parse fields that are words: ASCII letters spelling out in English AM/PM,
// day of week, month, or an extremely limited set of legacy time zone
// abbreviations.
if (IsAsciiAlpha(c)) {
size_t start = index - 1;
while (index < length) {
c = s[index];
if (!IsAsciiAlpha(c)) {
break;
}
index++;
}
// There must be at least as many letters as in the shortest keyword.
constexpr size_t MinLength = MinKeywordLength(keywords);
if (index - start < MinLength) {
return false;
}
// Record a month if it is a month name. Note that some numbers are
// initially treated as months; if a numeric field has already been
// interpreted as a month, store that value to the actually appropriate
// date component and set the month here.
int tryMonth;
if (IsMonthName(s + start, index - start, &tryMonth)) {
if (seenMonthName) {
// Overwrite the previous month name
mon = tryMonth;
prevc = 0;
continue;
}
seenMonthName = true;
if (mon < 0) {
mon = tryMonth;
} else if (mday < 0) {
mday = mon;
mon = tryMonth;
} else if (year < 0) {
if (mday > 0) {
// If the date is of the form f l month, then when month is
// reached we have f in mon and l in mday. In order to be
// consistent with the f month l and month f l forms, we need to
// swap so that f is in mday and l is in year.
year = mday;
mday = mon;
} else {
year = mon;
}
mon = tryMonth;
} else {
return false;
}
prevc = 0;
continue;
}
size_t k = std::size(keywords);
while (k-- > 0) {
const CharsAndAction& keyword = keywords[k];
// If the field doesn't match the keyword, try the next one.
if (!MatchesKeyword(s + start, index - start, keyword.chars)) {
continue;
}
int action = keyword.action;
if (action == 10000) {
seenGmtAbbr = true;
}
// Perform action tests from smallest action values to largest.
// Adjust a previously-specified hour for AM/PM accordingly (taking care
// to treat 12:xx AM as 00:xx, 12:xx PM as 12:xx).
if (action < 0) {
MOZ_ASSERT(action == -1 || action == -2);
if (hour > 12 || hour < 0) {
return false;
}
if (action == -1 && hour == 12) {
hour = 0;
} else if (action == -2 && hour != 12) {
hour += 12;
}
break;
}
// Finally, record a time zone offset.
MOZ_ASSERT(action >= 10000);
tzOffset = action - 10000;
break;
}
if (k == size_t(-1)) {
return false;
}
prevc = 0;
continue;
}
// Any other character fails to parse.
return false;
}
// Handle cases where the input is a single number. Single numbers >= 1000
// are handled by the spec (ParseISOStyleDate), so we don't need to account
// for that here.
if (mon != -1 && year < 0 && mday < 0) {
// Reject 13-31 for Chrome parity
if (mon >= 13 && mon <= 31) {
return false;
}
mday = 1;
if (mon >= 1 && mon <= 12) {
// 1-12 is parsed as a month with the year defaulted to 2001
// (again, for Chrome parity)
year = 2001;
} else {
year = FixupYear(mon);
mon = 1;
}
}
if (year < 0 || mon < 0 || mday < 0) {
return false;
}
if (!isDashedDate) {
// NOTE: TryParseDashedDatePrefix already handles the following fixup.
/*
* Case 1. The input string contains an English month name.
* The form of the string can be month f l, or f month l, or
* f l month which each evaluate to the same date.
* If f and l are both greater than or equal to 100 the date
* is invalid.
*
* The year is taken to be either l, f if f > 31, or whichever
* is set to zero.
*
* Case 2. The input string is of the form "f/m/l" where f, m and l are
* integers, e.g. 7/16/45. mon, mday and year values are adjusted
* to achieve Chrome compatibility.
*
* a. If 0 < f <= 12 and 0 < l <= 31, f/m/l is interpreted as
* month/day/year.
* b. If 31 < f and 0 < m <= 12 and 0 < l <= 31 f/m/l is
* interpreted as year/month/day
*/
if (seenMonthName) {
if (mday >= 100 && mon >= 100) {
return false;
}
if (year > 0 && (mday == 0 || mday > 31) && !seenFullYear) {
int temp = year;
year = mday;
mday = temp;
}
if (mday <= 0 || mday > 31) {
return false;
}
} else if (0 < mon && mon <= 12 && 0 < mday && mday <= 31) {
/* (a) month/day/year */
} else {
/* (b) year/month/day */
if (mon > 31 && mday <= 12 && year <= 31 && !seenFullYear) {
int temp = year;
year = mon;
mon = mday;
mday = temp;
} else {
return false;
}
}
year = FixupYear(year);
if (negativeYear) {
year = -year;
}
}
mon -= 1; /* convert month to 0-based */
if (sec < 0) {
sec = 0;
}
if (min < 0) {
min = 0;
}
if (hour < 0) {
hour = 0;
}
double date =
MakeDate(MakeDay(year, mon, mday), MakeTime(hour, min, sec, msec));
if (tzOffset == -1) { /* no time zone specified, have to use local */
date = UTC(forceUTC, date);
} else {
date += double(tzOffset) * msPerMinute;
}
*result = TimeClip(date);
return true;
}
static bool ParseDate(DateTimeInfo::ForceUTC forceUTC, const JSLinearString* s,
ClippedTime* result) {
AutoCheckCannotGC nogc;
return s->hasLatin1Chars()
? ParseDate(forceUTC, s->latin1Chars(nogc), s->length(), result)
: ParseDate(forceUTC, s->twoByteChars(nogc), s->length(), result);
}
/**
* 21.4.3.2 Date.parse ( string )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_parse(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date", "parse");
CallArgs args = CallArgsFromVp(argc, vp);
if (args.length() == 0) {
args.rval().setNaN();
return true;
}
JSString* str = ToString<CanGC>(cx, args[0]);
if (!str) {
return false;
}
JSLinearString* linearStr = str->ensureLinear(cx);
if (!linearStr) {
return false;
}
ClippedTime result;
if (!ParseDate(ForceUTC(cx->realm()), linearStr, &result)) {
args.rval().setNaN();
return true;
}
args.rval().set(TimeValue(result));
return true;
}
static ClippedTime NowAsMillis(JSContext* cx) {
if (js::SupportDifferentialTesting()) {
return TimeClip(0);
}
double now = PRMJ_Now();
bool clampAndJitter = cx->realm()->behaviors().clampAndJitterTime();
if (clampAndJitter && sReduceMicrosecondTimePrecisionCallback) {
now = sReduceMicrosecondTimePrecisionCallback(
now, cx->realm()->behaviors().reduceTimerPrecisionCallerType().value(),
cx);
} else if (clampAndJitter && sResolutionUsec) {
double clamped = floor(now / sResolutionUsec) * sResolutionUsec;
if (sJitter) {
// Calculate a random midpoint for jittering. In the browser, we are
// adversarial: Web Content may try to calculate the midpoint themselves
// and use that to bypass it's security. In the JS Shell, we are not
// adversarial, we want to jitter the time to recreate the operating
// environment, but we do not concern ourselves with trying to prevent an
// attacker from calculating the midpoint themselves. So we use a very
// simple, very fast CRC with a hardcoded seed.
uint64_t midpoint = BitwiseCast<uint64_t>(clamped);
midpoint ^= 0x0F00DD1E2BAD2DED; // XOR in a 'secret'
// MurmurHash3 internal component from
midpoint ^= midpoint >> 33;
midpoint *= uint64_t{0xFF51AFD7ED558CCD};
midpoint ^= midpoint >> 33;
midpoint *= uint64_t{0xC4CEB9FE1A85EC53};
midpoint ^= midpoint >> 33;
midpoint %= sResolutionUsec;
if (now > clamped + midpoint) { // We're jittering up to the next step
now = clamped + sResolutionUsec;
} else { // We're staying at the clamped value
now = clamped;
}
} else { // No jitter, only clamping
now = clamped;
}
}
return TimeClip(now / PRMJ_USEC_PER_MSEC);
}
JS::ClippedTime js::DateNow(JSContext* cx) { return NowAsMillis(cx); }
bool js::date_now(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date", "now");
CallArgs args = CallArgsFromVp(argc, vp);
args.rval().set(TimeValue(NowAsMillis(cx)));
return true;
}
DateTimeInfo::ForceUTC DateObject::forceUTC() const {
return ForceUTC(realm());
}
void DateObject::setUTCTime(ClippedTime t) {
for (size_t ind = COMPONENTS_START_SLOT; ind < RESERVED_SLOTS; ind++) {
setReservedSlot(ind, UndefinedValue());
}
setFixedSlot(UTC_TIME_SLOT, TimeValue(t));
}
void DateObject::setUTCTime(ClippedTime t, MutableHandleValue vp) {
setUTCTime(t);
vp.set(TimeValue(t));
}
void DateObject::fillLocalTimeSlots() {
const int32_t utcTZOffset =
DateTimeInfo::utcToLocalStandardOffsetSeconds(forceUTC());
/* Check if the cache is already populated. */
if (!getReservedSlot(LOCAL_TIME_SLOT).isUndefined() &&
getReservedSlot(UTC_TIME_ZONE_OFFSET_SLOT).toInt32() == utcTZOffset) {
return;
}
/* Remember time zone used to generate the local cache. */
setReservedSlot(UTC_TIME_ZONE_OFFSET_SLOT, Int32Value(utcTZOffset));
double utcTime = UTCTime().toDouble();
if (!std::isfinite(utcTime)) {
for (size_t ind = COMPONENTS_START_SLOT; ind < RESERVED_SLOTS; ind++) {
setReservedSlot(ind, DoubleValue(utcTime));
}
return;
}
int64_t localTime = LocalTime(forceUTC(), utcTime);
setReservedSlot(LOCAL_TIME_SLOT, DoubleValue(localTime));
const auto [year, month, day] = ToYearMonthDay(localTime);
setReservedSlot(LOCAL_YEAR_SLOT, Int32Value(year));
setReservedSlot(LOCAL_MONTH_SLOT, Int32Value(month));
setReservedSlot(LOCAL_DATE_SLOT, Int32Value(day));
int weekday = WeekDay(localTime);
setReservedSlot(LOCAL_DAY_SLOT, Int32Value(weekday));
int64_t yearStartTime = TimeFromYear(year);
uint64_t yearTime = uint64_t(localTime - yearStartTime);
int32_t yearSeconds = int32_t(yearTime / msPerSecond);
setReservedSlot(LOCAL_SECONDS_INTO_YEAR_SLOT, Int32Value(yearSeconds));
}
/**
* 21.4.4.10 Date.prototype.getTime ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getTime(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getTime");
if (!unwrapped) {
return false;
}
// Step 3.
args.rval().set(unwrapped->UTCTime());
return true;
}
/**
* B.2.3.1 Date.prototype.getYear ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getYear");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
Value yearVal = unwrapped->localYear();
if (yearVal.isInt32()) {
int year = yearVal.toInt32() - 1900;
args.rval().setInt32(year);
} else {
args.rval().set(yearVal);
}
return true;
}
/**
* 21.4.4.4 Date.prototype.getFullYear ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getFullYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getFullYear");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
args.rval().set(unwrapped->localYear());
return true;
}
/**
* 21.4.4.18 Date.prototype.getUTCMonth ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCFullYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCFullYear");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(::YearFromTime(tv));
return true;
}
/**
* 21.4.4.8 Date.prototype.getMonth ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getMonth(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getMonth");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
args.rval().set(unwrapped->localMonth());
return true;
}
/**
* 21.4.4.18 Date.prototype.getUTCMonth ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCMonth(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCMonth");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(::MonthFromTime(tv));
return true;
}
/**
* 21.4.4.2 Date.prototype.getDate ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getDate(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getDate");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
args.rval().set(unwrapped->localDate());
return true;
}
/**
* 21.4.4.12 Date.prototype.getUTCDate ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCDate(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCDate");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(DateFromTime(tv));
return true;
}
/**
* 21.4.4.3 Date.prototype.getDay ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getDay(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getDay");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
args.rval().set(unwrapped->localDay());
return true;
}
/**
* 21.4.4.13 Date.prototype.getUTCDay ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCDay(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCDay");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(WeekDay(tv));
return true;
}
/**
* 21.4.4.5 Date.prototype.getHours ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getHours(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getHours");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
// Note: localSecondsIntoYear is guaranteed to return an
// int32 or NaN after the call to fillLocalTimeSlots.
Value yearSeconds = unwrapped->localSecondsIntoYear();
if (yearSeconds.isDouble()) {
MOZ_ASSERT(std::isnan(yearSeconds.toDouble()));
args.rval().set(yearSeconds);
} else {
args.rval().setInt32((yearSeconds.toInt32() / SecondsPerHour) %
HoursPerDay);
}
return true;
}
/**
* 21.4.4.15 Date.prototype.getUTCHours ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCHours(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCHours");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(HourFromTime(tv));
return true;
}
/**
* 21.4.4.7 Date.prototype.getMinutes ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getMinutes(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getMinutes");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
// Note: localSecondsIntoYear is guaranteed to return an
// int32 or NaN after the call to fillLocalTimeSlots.
Value yearSeconds = unwrapped->localSecondsIntoYear();
if (yearSeconds.isDouble()) {
MOZ_ASSERT(std::isnan(yearSeconds.toDouble()));
args.rval().set(yearSeconds);
} else {
args.rval().setInt32((yearSeconds.toInt32() / SecondsPerMinute) %
MinutesPerHour);
}
return true;
}
/**
* 21.4.4.17 Date.prototype.getUTCMinutes ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCMinutes(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCMinutes");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(MinFromTime(tv));
return true;
}
/**
* 21.4.4.9 Date.prototype.getSeconds ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getSeconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "getSeconds");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
// Note: localSecondsIntoYear is guaranteed to return an
// int32 or NaN after the call to fillLocalTimeSlots.
Value yearSeconds = unwrapped->localSecondsIntoYear();
if (yearSeconds.isDouble()) {
MOZ_ASSERT(std::isnan(yearSeconds.toDouble()));
args.rval().set(yearSeconds);
} else {
args.rval().setInt32(yearSeconds.toInt32() % SecondsPerMinute);
}
return true;
}
/**
* 21.4.4.19 Date.prototype.getUTCSeconds ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getUTCSeconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "getUTCSeconds");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(SecFromTime(tv));
return true;
}
/*
* Date.getMilliseconds is mapped to getUTCMilliseconds. As long as no
* supported time zone has a fractional-second component, the differences in
* their specifications aren't observable.
*
* The 'tz' database explicitly does not support fractional-second time zones.
* For example the Netherlands observed Amsterdam Mean Time, estimated to be
* UT +00:19:32.13, from 1909 to 1937, but in tzdata AMT is defined as exactly
* UT +00:19:32.
*/
/**
* 21.4.4.6 Date.prototype.getMilliseconds ( )
* 21.4.4.16 Date.prototype.getUTCMilliseconds ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool getMilliseconds(JSContext* cx, unsigned argc, Value* vp,
const char* methodName) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, methodName);
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 5.
args.rval().setInt32(msFromTime(tv));
return true;
}
static bool date_getMilliseconds(JSContext* cx, unsigned argc, Value* vp) {
return getMilliseconds(cx, argc, vp, "getMilliseconds");
}
static bool date_getUTCMilliseconds(JSContext* cx, unsigned argc, Value* vp) {
return getMilliseconds(cx, argc, vp, "getUTCMilliseconds");
}
/**
* 21.4.4.11 Date.prototype.getTimezoneOffset ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_getTimezoneOffset(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "getTimezoneOffset");
if (!unwrapped) {
return false;
}
// Steps 3-5.
unwrapped->fillLocalTimeSlots();
double utctime = unwrapped->UTCTime().toDouble();
double localtime = unwrapped->localTime().toDouble();
/*
* Return the time zone offset in minutes for the current locale that is
* appropriate for this time. This value would be a constant except for
* daylight savings time.
*/
double result = (utctime - localtime) / double(msPerMinute);
args.rval().setNumber(result);
return true;
}
/**
* 21.4.4.27 Date.prototype.setTime ( time )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setTime(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setTime"));
if (!unwrapped) {
return false;
}
// Step 3.
double result;
if (!ToNumber(cx, args.get(0), &result)) {
return false;
}
// Steps 4-6.
unwrapped->setUTCTime(TimeClip(result), args.rval());
return true;
}
/**
* 21.4.4.23 Date.prototype.setMilliseconds ( ms )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setMilliseconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setMilliseconds"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double ms;
if (!ToNumber(cx, args.get(0), &ms)) {
return false;
}
// Step 5.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 6.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 7.
double time =
MakeTime(HourFromTime(tv), MinFromTime(tv), SecFromTime(tv), ms);
// Step 8.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), MakeDate(Day(tv), time)));
// Steps 9-10.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.31 Date.prototype.setUTCMilliseconds ( ms )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCMilliseconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCMilliseconds"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double milli;
if (!ToNumber(cx, args.get(0), &milli)) {
return false;
}
// Step 5.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 6.
double time =
MakeTime(HourFromTime(tv), MinFromTime(tv), SecFromTime(tv), milli);
// Step 7.
ClippedTime v = TimeClip(MakeDate(Day(tv), time));
// Steps 8-9.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.26 Date.prototype.setSeconds ( sec [ , ms ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setSeconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setSeconds"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double s;
if (!ToNumber(cx, args.get(0), &s)) {
return false;
}
// Step 5.
double milli;
if (args.length() > 1 && !ToNumber(cx, args[1], &milli)) {
return false;
}
// Step 6.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 7.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 8.
if (args.length() <= 1) {
milli = msFromTime(tv);
}
// Step 9.
double date =
MakeDate(Day(tv), MakeTime(HourFromTime(tv), MinFromTime(tv), s, milli));
// Step 10.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), date));
// Steps 11-12.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.34 Date.prototype.setUTCSeconds ( sec [ , ms ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCSeconds(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCSeconds"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double s;
if (!ToNumber(cx, args.get(0), &s)) {
return false;
}
// Step 5.
double milli;
if (args.length() > 1 && !ToNumber(cx, args[1], &milli)) {
return false;
}
// Step 6.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 7.
if (args.length() <= 1) {
milli = msFromTime(tv);
}
// Step 8.
double date =
MakeDate(Day(tv), MakeTime(HourFromTime(tv), MinFromTime(tv), s, milli));
// Step 9.
ClippedTime v = TimeClip(date);
// Steps 10-11.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.24 Date.prototype.setMinutes ( min [ , sec [ , ms ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setMinutes(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setMinutes"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double m;
if (!ToNumber(cx, args.get(0), &m)) {
return false;
}
// Step 5.
double s;
if (args.length() > 1 && !ToNumber(cx, args[1], &s)) {
return false;
}
// Step 6.
double milli;
if (args.length() > 2 && !ToNumber(cx, args[2], &milli)) {
return false;
}
// Step 7.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 8.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 9.
if (args.length() <= 1) {
s = SecFromTime(tv);
}
// Step 10.
if (args.length() <= 2) {
milli = msFromTime(tv);
}
// Step 11.
double date = MakeDate(Day(tv), MakeTime(HourFromTime(tv), m, s, milli));
// Step 12.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), date));
// Steps 13-14.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.32 Date.prototype.setUTCMinutes ( min [ , sec [ , ms ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCMinutes(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCMinutes"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double m;
if (!ToNumber(cx, args.get(0), &m)) {
return false;
}
// Step 5.
double s;
if (args.length() > 1 && !ToNumber(cx, args[1], &s)) {
return false;
}
// Step 6.
double milli;
if (args.length() > 2 && !ToNumber(cx, args[2], &milli)) {
return false;
}
// Step 7.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 8.
if (args.length() <= 1) {
s = SecFromTime(tv);
}
// Step 9.
if (args.length() <= 2) {
milli = msFromTime(tv);
}
// Step 10.
double date = MakeDate(Day(tv), MakeTime(HourFromTime(tv), m, s, milli));
// Step 11.
ClippedTime v = TimeClip(date);
// Steps 12-13.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.22 Date.prototype.setHours ( hour [ , min [ , sec [ , ms ] ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setHours(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setHours"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double h;
if (!ToNumber(cx, args.get(0), &h)) {
return false;
}
// Step 5.
double m;
if (args.length() > 1 && !ToNumber(cx, args[1], &m)) {
return false;
}
// Step 6.
double s;
if (args.length() > 2 && !ToNumber(cx, args[2], &s)) {
return false;
}
// Step 7.
double milli;
if (args.length() > 3 && !ToNumber(cx, args[3], &milli)) {
return false;
}
// Step 8.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 9.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 10.
if (args.length() <= 1) {
m = MinFromTime(tv);
}
// Step 11.
if (args.length() <= 2) {
s = SecFromTime(tv);
}
// Step 12.
if (args.length() <= 3) {
milli = msFromTime(tv);
}
// Step 13.
double date = MakeDate(Day(tv), MakeTime(h, m, s, milli));
// Step 14.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), date));
// Steps 15-16.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.30 Date.prototype.setUTCHours ( hour [ , min [ , sec [ , ms ] ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCHours(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCHours"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double h;
if (!ToNumber(cx, args.get(0), &h)) {
return false;
}
// Step 5.
double m;
if (args.length() > 1 && !ToNumber(cx, args[1], &m)) {
return false;
}
// Step 6.
double s;
if (args.length() > 2 && !ToNumber(cx, args[2], &s)) {
return false;
}
// Step 7.
double milli;
if (args.length() > 3 && !ToNumber(cx, args[3], &milli)) {
return false;
}
// Step 8.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 9.
if (args.length() <= 1) {
m = MinFromTime(tv);
}
// Step 10.
if (args.length() <= 2) {
s = SecFromTime(tv);
}
// Step 11.
if (args.length() <= 3) {
milli = msFromTime(tv);
}
// Step 12.
double date = MakeDate(Day(tv), MakeTime(h, m, s, milli));
// Step 13.
ClippedTime v = TimeClip(date);
// Steps 14-15.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.20 Date.prototype.setDate ( date )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setDate(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setDate"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double dt;
if (!ToNumber(cx, args.get(0), &dt)) {
return false;
}
// Step 5.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 6.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 7.
double newDate = MakeDate(
MakeDay(::YearFromTime(tv), ::MonthFromTime(tv), dt), TimeWithinDay(tv));
// Step 8.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), newDate));
// Steps 9-10.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.28 Date.prototype.setUTCDate ( date )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCDate(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCDate"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double dt;
if (!ToNumber(cx, args.get(0), &dt)) {
return false;
}
// Step 5.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 6.
double newDate = MakeDate(
MakeDay(::YearFromTime(tv), ::MonthFromTime(tv), dt), TimeWithinDay(tv));
// Step 7.
ClippedTime v = TimeClip(newDate);
// Steps 8-9.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.25 Date.prototype.setMonth ( month [ , date ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setMonth(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setMonth"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double m;
if (!ToNumber(cx, args.get(0), &m)) {
return false;
}
// Step 5.
double dt;
if (args.length() > 1 && !ToNumber(cx, args[1], &dt)) {
return false;
}
// Step 6.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
// Step 7.
int64_t tv = LocalTime(unwrapped->forceUTC(), t);
// Step 8.
if (args.length() <= 1) {
dt = DateFromTime(tv);
}
// Step 9.
double newDate =
MakeDate(MakeDay(::YearFromTime(tv), m, dt), TimeWithinDay(tv));
// Step 10
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), newDate));
// Steps 11-12.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.33 Date.prototype.setUTCMonth ( month [ , date ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCMonth(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCMonth"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double m;
if (!ToNumber(cx, args.get(0), &m)) {
return false;
}
// Step 5.
double dt;
if (args.length() > 1 && !ToNumber(cx, args[1], &dt)) {
return false;
}
// Step 6.
if (std::isnan(t)) {
args.rval().setNaN();
return true;
}
int64_t tv = static_cast<int64_t>(t);
// Step 7.
if (args.length() <= 1) {
dt = DateFromTime(tv);
}
// Step 8.
double newDate =
MakeDate(MakeDay(::YearFromTime(tv), m, dt), TimeWithinDay(tv));
// Step 9.
ClippedTime v = TimeClip(newDate);
// Steps 10-11.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* 21.4.4.21 Date.prototype.setFullYear ( year [ , month [ , date ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setFullYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setFullYear"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double y;
if (!ToNumber(cx, args.get(0), &y)) {
return false;
}
// Step 5.
int64_t tv;
if (std::isnan(t)) {
tv = 0;
} else {
tv = LocalTime(unwrapped->forceUTC(), t);
}
// Step 6.
double m;
if (args.length() <= 1) {
m = MonthFromTime(tv);
} else {
if (!ToNumber(cx, args[1], &m)) {
return false;
}
}
// Step 7.
double dt;
if (args.length() <= 2) {
dt = DateFromTime(tv);
} else {
if (!ToNumber(cx, args[2], &dt)) {
return false;
}
}
// Step 8.
double newDate = MakeDate(MakeDay(y, m, dt), TimeWithinDay(tv));
// Step 9.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), newDate));
// Steps 10-11.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* 21.4.4.29 Date.prototype.setUTCFullYear ( year [ , month [ , date ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setUTCFullYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setUTCFullYear"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
int64_t tv;
if (std::isnan(t)) {
tv = 0;
} else {
tv = static_cast<int64_t>(t);
}
// Step 5.
double y;
if (!ToNumber(cx, args.get(0), &y)) {
return false;
}
// Step 6.
double m;
if (args.length() <= 1) {
m = MonthFromTime(tv);
} else {
if (!ToNumber(cx, args[1], &m)) {
return false;
}
}
// Step 7.
double dt;
if (args.length() <= 2) {
dt = DateFromTime(tv);
} else {
if (!ToNumber(cx, args[2], &dt)) {
return false;
}
}
// Step 8.
double newDate = MakeDate(MakeDay(y, m, dt), TimeWithinDay(tv));
// Step 9.
ClippedTime v = TimeClip(newDate);
// Steps 10-11.
unwrapped->setUTCTime(v, args.rval());
return true;
}
/**
* B.2.3.2 Date.prototype.setYear ( year )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_setYear(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
Rooted<DateObject*> unwrapped(
cx, UnwrapAndTypeCheckThis<DateObject>(cx, args, "setYear"));
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
double y;
if (!ToNumber(cx, args.get(0), &y)) {
return false;
}
// Step 5.
int64_t tv;
if (std::isnan(t)) {
tv = 0;
} else {
tv = LocalTime(unwrapped->forceUTC(), t);
}
// Step 6.
double yyyy = MakeFullYear(y);
// Step 7.
double day = MakeDay(yyyy, ::MonthFromTime(tv), DateFromTime(tv));
// Step 8.
double date = MakeDate(day, TimeWithinDay(tv));
// Step 9.
ClippedTime u = TimeClip(UTC(unwrapped->forceUTC(), date));
// Steps 10-11.
unwrapped->setUTCTime(u, args.rval());
return true;
}
/**
* Simple date formatter for toISOString, toUTCString, and FormatDate.
*/
class DateFormatter {
// Longest possible string is 36 characters. Round up to the next multiple of
// sixteen.
static constexpr size_t BufferLength = 48;
char buffer_[BufferLength] = {};
char* ptr_ = buffer_;
size_t written() const { return size_t(ptr_ - buffer_); }
static constexpr uint32_t powerOfTen(uint32_t exp) {
uint32_t result = 1;
while (exp--) {
result *= 10;
}
return result;
}
// Add |N| digits, padded with zeroes.
template <uint32_t N>
void digits(uint32_t value) {
static_assert(1 <= N && N <= 6);
MOZ_ASSERT(written() + N <= BufferLength);
constexpr uint32_t divisor = powerOfTen(N - 1);
MOZ_ASSERT(value < divisor * 10);
uint32_t quot = value / divisor;
[[maybe_unused]] uint32_t rem = value % divisor;
*ptr_++ = char('0' + quot);
if constexpr (N > 1) {
digits<N - 1>(rem);
}
}
// Constants for toString and toUTCString.
static constexpr char const days[][4] = {
"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat",
};
static constexpr char const months[][4] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
};
public:
std::string_view string() const { return {buffer_, written()}; }
auto& literal(char ch) {
MOZ_ASSERT(written() + 1 <= BufferLength);
*ptr_++ = ch;
return *this;
}
template <size_t N>
auto& literal(const char (&str)[N]) {
static_assert(N > 0);
size_t length = N - 1;
MOZ_ASSERT(written() + length <= BufferLength);
std::memcpy(ptr_, str, length);
ptr_ += length;
return *this;
}
auto& year(int32_t value) {
MOZ_ASSERT(-999'999 <= value && value <= 999'999);
if (value < 0) {
literal('-');
value = std::abs(value);
}
if (value <= 9999) {
digits<4>(value);
} else if (value <= 99999) {
digits<5>(value);
} else {
digits<6>(value);
}
return *this;
}
auto& isoYear(int32_t value) {
MOZ_ASSERT(-999'999 <= value && value <= 999'999);
if (0 <= value && value <= 9999) {
digits<4>(value);
} else {
literal(value < 0 ? '-' : '+');
digits<6>(std::abs(value));
}
return *this;
}
auto& month(int32_t value) {
MOZ_ASSERT(1 <= value && value <= 12);
digits<2>(value);
return *this;
}
auto& day(int32_t value) {
MOZ_ASSERT(1 <= value && value <= 31);
digits<2>(value);
return *this;
}
auto& hour(int32_t value) {
MOZ_ASSERT(0 <= value && value <= 23);
digits<2>(value);
return *this;
}
auto& minute(int32_t value) {
MOZ_ASSERT(0 <= value && value <= 59);
digits<2>(value);
return *this;
}
auto& second(int32_t value) {
MOZ_ASSERT(0 <= value && value <= 59);
digits<2>(value);
return *this;
}
auto& time(int32_t h, int32_t m, int32_t s) {
return hour(h).literal(':').minute(m).literal(':').second(s);
}
auto& millisecond(int32_t value) {
MOZ_ASSERT(0 <= value && value <= 999);
digits<3>(value);
return *this;
}
auto& monthName(int32_t value) {
MOZ_ASSERT(0 <= value && value < 12);
return literal(months[value]);
}
auto& weekDay(int32_t value) {
MOZ_ASSERT(0 <= value && value < 7);
return literal(days[value]);
}
auto& timeZoneOffset(int32_t value) {
MOZ_ASSERT(-2400 < value && value < 2400);
literal(value < 0 ? '-' : '+');
digits<4>(std::abs(value));
return *this;
}
};
/**
* 21.4.4.43 Date.prototype.toUTCString ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toUTCString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toUTCString");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "toUTCString");
if (!unwrapped) {
return false;
}
// Step 3.
double utctime = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(utctime));
// Step 4.
if (std::isnan(utctime)) {
args.rval().setString(cx->names().Invalid_Date_);
return true;
}
int64_t epochMilliseconds = static_cast<int64_t>(utctime);
// Steps 5-11.
auto [year, month, day] = ToYearMonthDay(epochMilliseconds);
auto [hour, minute, second] = ToHourMinuteSecond(epochMilliseconds);
DateFormatter fmt{};
fmt.weekDay(WeekDay(epochMilliseconds))
.literal(", ")
.day(day)
.literal(' ')
.monthName(month)
.literal(' ')
.year(year)
.literal(' ')
.time(hour, minute, second)
.literal(" GMT");
JSString* str = NewStringCopy<CanGC>(cx, fmt.string());
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
/**
* 21.4.4.36 Date.prototype.toISOString ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toISOString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toISOString");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "toISOString");
if (!unwrapped) {
return false;
}
// Steps 3 and 5.
double utctime = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(utctime));
// Step 4.
if (!std::isfinite(utctime)) {
JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr,
JSMSG_INVALID_DATE);
return false;
}
int64_t epochMilliseconds = static_cast<int64_t>(utctime);
// Step 6. (Not applicable in our implementation.)
// Step 7.
auto [year, month, day] = ToYearMonthDay(epochMilliseconds);
auto [hour, minute, second] = ToHourMinuteSecond(epochMilliseconds);
DateFormatter fmt{};
fmt.isoYear(year)
.literal('-')
.month(month + 1)
.literal('-')
.day(day)
.literal('T')
.time(hour, minute, second)
.literal('.')
.millisecond(msFromTime(epochMilliseconds))
.literal('Z');
JSString* str = NewStringCopy<CanGC>(cx, fmt.string());
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
/**
* 21.4.4.37 Date.prototype.toJSON ( key )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toJSON(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toJSON");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1.
RootedObject obj(cx, ToObject(cx, args.thisv()));
if (!obj) {
return false;
}
// Step 2.
RootedValue tv(cx, ObjectValue(*obj));
if (!ToPrimitive(cx, JSTYPE_NUMBER, &tv)) {
return false;
}
// Step 3.
if (tv.isDouble() && !std::isfinite(tv.toDouble())) {
args.rval().setNull();
return true;
}
// Step 4.
RootedValue toISO(cx);
if (!GetProperty(cx, obj, obj, cx->names().toISOString, &toISO)) {
return false;
}
if (!IsCallable(toISO)) {
JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr,
JSMSG_BAD_TOISOSTRING_PROP);
return false;
}
return Call(cx, toISO, obj, args.rval());
}
#if JS_HAS_INTL_API
JSString* DateTimeHelper::timeZoneComment(JSContext* cx,
DateTimeInfo::ForceUTC forceUTC,
const char* locale, int64_t utcTime,
int64_t localTime) {
MOZ_ASSERT(IsTimeValue(utcTime));
MOZ_ASSERT(IsLocalTimeValue(localTime));
char16_t tzbuf[100];
tzbuf[0] = ' ';
tzbuf[1] = '(';
char16_t* timeZoneStart = tzbuf + 2;
constexpr size_t remainingSpace =
std::size(tzbuf) - 2 - 1; // for the trailing ')'
if (!DateTimeInfo::timeZoneDisplayName(forceUTC, timeZoneStart,
remainingSpace, utcTime, locale)) {
JS_ReportOutOfMemory(cx);
return nullptr;
}
// Reject if the result string is empty.
size_t len = js_strlen(timeZoneStart);
if (len == 0) {
return cx->names().empty_;
}
// Parenthesize the returned display name.
timeZoneStart[len] = ')';
return NewStringCopyN<CanGC>(cx, tzbuf, 2 + len + 1);
}
#else
/* Interface to PRMJTime date struct. */
PRMJTime DateTimeHelper::toPRMJTime(DateTimeInfo::ForceUTC forceUTC,
int64_t localTime, int64_t utcTime) {
auto [year, month, day] = ToYearMonthDay(localTime);
auto [hour, minute, second] = ToHourMinuteSecond(localTime);
PRMJTime prtm;
prtm.tm_usec = int32_t(msFromTime(localTime)) * 1000;
prtm.tm_sec = int8_t(second);
prtm.tm_min = int8_t(minute);
prtm.tm_hour = int8_t(hour);
prtm.tm_mday = int8_t(day);
prtm.tm_mon = int8_t(month);
prtm.tm_wday = int8_t(WeekDay(localTime));
prtm.tm_year = year;
prtm.tm_yday = int16_t(::DayWithinYear(localTime, year));
prtm.tm_isdst = (daylightSavingTA(forceUTC, utcTime) != 0);
return prtm;
}
size_t DateTimeHelper::formatTime(DateTimeInfo::ForceUTC forceUTC, char* buf,
size_t buflen, const char* fmt,
int64_t utcTime, int64_t localTime) {
PRMJTime prtm = toPRMJTime(forceUTC, localTime, utcTime);
// If an equivalent year was used to compute the date/time components, use
// the same equivalent year to determine the time zone name and offset in
// PRMJ_FormatTime(...).
int timeZoneYear = isRepresentableAsTime32(utcTime)
? prtm.tm_year
: equivalentYearForDST(prtm.tm_year);
int32_t offsetInSeconds = FloorDiv(localTime - utcTime, msPerSecond);
return PRMJ_FormatTime(buf, buflen, fmt, &prtm, timeZoneYear,
offsetInSeconds);
}
JSString* DateTimeHelper::timeZoneComment(JSContext* cx,
DateTimeInfo::ForceUTC forceUTC,
const char* locale, int64_t utcTime,
int64_t localTime) {
char tzbuf[100];
size_t tzlen =
formatTime(forceUTC, tzbuf, sizeof tzbuf, " (%Z)", utcTime, localTime);
if (tzlen != 0) {
// Decide whether to use the resulting time zone string.
//
// Reject it if it contains any non-ASCII or non-printable characters.
// It's then likely in some other character encoding, and we probably
// won't display it correctly.
bool usetz = true;
for (size_t i = 0; i < tzlen; i++) {
char16_t c = tzbuf[i];
if (!IsAsciiPrintable(c)) {
usetz = false;
break;
}
}
// Also reject it if it's not parenthesized or if it's ' ()'.
if (tzbuf[0] != ' ' || tzbuf[1] != '(' || tzbuf[2] == ')') {
usetz = false;
}
if (usetz) {
return NewStringCopyN<CanGC>(cx, tzbuf, tzlen);
}
}
return cx->names().empty_;
}
#endif /* JS_HAS_INTL_API */
enum class FormatSpec { DateTime, Date, Time };
static bool FormatDate(JSContext* cx, DateTimeInfo::ForceUTC forceUTC,
const char* locale, double utcTime, FormatSpec format,
MutableHandleValue rval) {
MOZ_ASSERT(IsTimeValue(utcTime));
if (!std::isfinite(utcTime)) {
rval.setString(cx->names().Invalid_Date_);
return true;
}
int64_t epochMilliseconds = static_cast<int64_t>(utcTime);
int64_t localTime = LocalTime(forceUTC, utcTime);
int offset = 0;
RootedString timeZoneComment(cx);
if (format == FormatSpec::DateTime || format == FormatSpec::Time) {
// Offset from GMT in minutes. The offset includes daylight savings,
// if it applies.
int32_t minutes = int32_t(localTime - epochMilliseconds) / msPerMinute;
// Map 510 minutes to 0830 hours.
offset = (minutes / 60) * 100 + minutes % 60;
// Print as "Wed Nov 05 1997 19:38:03 GMT-0800 (PST)".
//
// The TZA is printed as 'GMT-0800' rather than as 'PST' to avoid
// operating-system dependence on strftime (which PRMJ_FormatTime
// calls, for %Z only.) win32 prints PST as 'Pacific Standard Time.'
// This way we always know what we're getting, and can parse it if
// we produce it. The OS time zone string is included as a comment.
//
// When ICU is used to retrieve the time zone string, the localized
// 'long' name format from CLDR is used. For example when the default
// locale is "en-US", PST is displayed as 'Pacific Standard Time', but
// when it is "ru", 'Тихоокеанское стандартное время' is used. This
// also means the time zone string may not fit into Latin-1.
// Get a time zone string from the OS or ICU to include as a comment.
timeZoneComment = DateTimeHelper::timeZoneComment(
cx, forceUTC, locale, epochMilliseconds, localTime);
if (!timeZoneComment) {
return false;
}
}
DateFormatter fmt{};
switch (format) {
case FormatSpec::DateTime: {
/* Tue Oct 31 2000 09:41:40 GMT-0800 */
auto [year, month, day] = ToYearMonthDay(localTime);
auto [hour, minute, second] = ToHourMinuteSecond(localTime);
fmt.weekDay(WeekDay(localTime))
.literal(' ')
.monthName(month)
.literal(' ')
.day(day)
.literal(' ')
.year(year)
.literal(' ')
.time(hour, minute, second)
.literal(" GMT")
.timeZoneOffset(offset);
break;
}
case FormatSpec::Date: {
/* Tue Oct 31 2000 */
auto [year, month, day] = ToYearMonthDay(localTime);
fmt.weekDay(WeekDay(localTime))
.literal(' ')
.monthName(month)
.literal(' ')
.day(day)
.literal(' ')
.year(year);
break;
}
case FormatSpec::Time:
/* 09:41:40 GMT-0800 */
auto [hour, minute, second] = ToHourMinuteSecond(localTime);
fmt.time(hour, minute, second).literal(" GMT").timeZoneOffset(offset);
break;
}
RootedString str(cx, NewStringCopy<CanGC>(cx, fmt.string()));
if (!str) {
return false;
}
// Append the time zone string if present.
if (timeZoneComment && !timeZoneComment->empty()) {
str = js::ConcatStrings<CanGC>(cx, str, timeZoneComment);
if (!str) {
return false;
}
}
rval.setString(str);
return true;
}
#if !JS_HAS_INTL_API
static bool ToLocaleFormatHelper(JSContext* cx, DateObject* unwrapped,
const char* format, MutableHandleValue rval) {
DateTimeInfo::ForceUTC forceUTC = unwrapped->forceUTC();
double utcTime = unwrapped->UTCTime().toDouble();
const char* locale = unwrapped->realm()->getLocale();
if (!locale) {
return false;
}
char buf[100];
if (!std::isfinite(utcTime)) {
strcpy(buf, "InvalidDate");
} else {
MOZ_ASSERT(IsTimeValue(utcTime));
int64_t epochMilliseconds = static_cast<int64_t>(utcTime);
int64_t localTime = static_cast<int64_t>(LocalTime(forceUTC, utcTime));
/* Let PRMJTime format it. */
size_t result_len = DateTimeHelper::formatTime(
forceUTC, buf, sizeof buf, format, epochMilliseconds, localTime);
/* If it failed, default to toString. */
if (result_len == 0) {
return FormatDate(cx, forceUTC, locale, utcTime, FormatSpec::DateTime,
rval);
}
/* Hacked check against undesired 2-digit year 00/00/00 form. */
if (strcmp(format, "%x") == 0 && result_len >= 6 &&
/* Format %x means use OS settings, which may have 2-digit yr, so
hack end of 3/11/22 or 11.03.22 or 11Mar22 to use 4-digit yr...*/
!IsAsciiDigit(buf[result_len - 3]) &&
IsAsciiDigit(buf[result_len - 2]) &&
IsAsciiDigit(buf[result_len - 1]) &&
/* ...but not if starts with 4-digit year, like 2022/3/11. */
!(IsAsciiDigit(buf[0]) && IsAsciiDigit(buf[1]) &&
IsAsciiDigit(buf[2]) && IsAsciiDigit(buf[3]))) {
int year = int(::YearFromTime(localTime));
snprintf(buf + (result_len - 2), (sizeof buf) - (result_len - 2), "%d",
year);
}
}
if (cx->runtime()->localeCallbacks &&
cx->runtime()->localeCallbacks->localeToUnicode) {
return cx->runtime()->localeCallbacks->localeToUnicode(cx, buf, rval);
}
JSString* str = NewStringCopyZ<CanGC>(cx, buf);
if (!str) {
return false;
}
rval.setString(str);
return true;
}
/**
* 21.4.4.39 Date.prototype.toLocaleString ( [ reserved1 [ , reserved2 ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toLocaleString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toLocaleString");
CallArgs args = CallArgsFromVp(argc, vp);
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toLocaleString");
if (!unwrapped) {
return false;
}
/*
* Use '%#c' for windows, because '%c' is backward-compatible and non-y2k
* with msvc; '%#c' requests that a full year be used in the result string.
*/
static const char format[] =
# if defined(_WIN32)
"%#c"
# else
"%c"
# endif
;
return ToLocaleFormatHelper(cx, unwrapped, format, args.rval());
}
/**
* 21.4.4.38 Date.prototype.toLocaleDateString ( [ reserved1 [ , reserved2 ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toLocaleDateString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype",
"toLocaleDateString");
CallArgs args = CallArgsFromVp(argc, vp);
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toLocaleDateString");
if (!unwrapped) {
return false;
}
/*
* Use '%#x' for windows, because '%x' is backward-compatible and non-y2k
* with msvc; '%#x' requests that a full year be used in the result string.
*/
static const char format[] =
# if defined(_WIN32)
"%#x"
# else
"%x"
# endif
;
return ToLocaleFormatHelper(cx, unwrapped, format, args.rval());
}
/**
* 21.4.4.40 Date.prototype.toLocaleTimeString ( [ reserved1 [ , reserved2 ] ] )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toLocaleTimeString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype",
"toLocaleTimeString");
CallArgs args = CallArgsFromVp(argc, vp);
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toLocaleTimeString");
if (!unwrapped) {
return false;
}
return ToLocaleFormatHelper(cx, unwrapped, "%X", args.rval());
}
#endif /* !JS_HAS_INTL_API */
/**
* 21.4.4.42 Date.prototype.toTimeString ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toTimeString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toTimeString");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toTimeString");
if (!unwrapped) {
return false;
}
// Steps 3-6.
const char* locale = unwrapped->realm()->getLocale();
if (!locale) {
return false;
}
return FormatDate(cx, unwrapped->forceUTC(), locale,
unwrapped->UTCTime().toDouble(), FormatSpec::Time,
args.rval());
}
/**
* 21.4.4.35 Date.prototype.toDateString ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toDateString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toDateString");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toDateString");
if (!unwrapped) {
return false;
}
// Steps 3-6.
const char* locale = unwrapped->realm()->getLocale();
if (!locale) {
return false;
}
return FormatDate(cx, unwrapped->forceUTC(), locale,
unwrapped->UTCTime().toDouble(), FormatSpec::Date,
args.rval());
}
static bool date_toSource(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toSource");
CallArgs args = CallArgsFromVp(argc, vp);
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "toSource");
if (!unwrapped) {
return false;
}
JSStringBuilder sb(cx);
if (!sb.append("(new Date(") ||
!NumberValueToStringBuilder(unwrapped->UTCTime(), sb) ||
!sb.append("))")) {
return false;
}
JSString* str = sb.finishString();
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
/**
* 21.4.4.41 Date.prototype.toString ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool date_toString(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "Date.prototype", "toString");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "toString");
if (!unwrapped) {
return false;
}
// Steps 3-4.
const char* locale = unwrapped->realm()->getLocale();
if (!locale) {
return false;
}
return FormatDate(cx, unwrapped->forceUTC(), locale,
unwrapped->UTCTime().toDouble(), FormatSpec::DateTime,
args.rval());
}
/**
* 21.4.4.44 Date.prototype.valueOf ( )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
bool js::date_valueOf(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped = UnwrapAndTypeCheckThis<DateObject>(cx, args, "valueOf");
if (!unwrapped) {
return false;
}
// Step 3.
args.rval().set(unwrapped->UTCTime());
return true;
}
/**
* 21.4.4.45 Date.prototype [ %Symbol.toPrimitive% ] ( hint )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
bool js::date_toPrimitive(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
if (!args.thisv().isObject()) {
ReportIncompatible(cx, args);
return false;
}
// Steps 3-5.
JSType hint;
if (!GetFirstArgumentAsTypeHint(cx, args, &hint)) {
return false;
}
if (hint == JSTYPE_UNDEFINED) {
hint = JSTYPE_STRING;
}
// Step 6.
RootedObject obj(cx, &args.thisv().toObject());
return OrdinaryToPrimitive(cx, obj, hint, args.rval());
}
#if JS_HAS_TEMPORAL_API
/**
* Date.prototype.toTemporalInstant ( )
*/
static bool date_toTemporalInstant(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
auto* unwrapped =
UnwrapAndTypeCheckThis<DateObject>(cx, args, "toTemporalInstant");
if (!unwrapped) {
return false;
}
// Step 3.
double t = unwrapped->UTCTime().toDouble();
MOZ_ASSERT(IsTimeValue(t));
// Step 4.
if (std::isnan(t)) {
JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr,
JSMSG_INVALID_DATE);
return false;
}
int64_t tv = static_cast<int64_t>(t);
auto epochNs = temporal::EpochNanoseconds::fromMilliseconds(tv);
MOZ_ASSERT(temporal::IsValidEpochNanoseconds(epochNs));
// Step 5.
auto* result = temporal::CreateTemporalInstant(cx, epochNs);
if (!result) {
return false;
}
args.rval().setObject(*result);
return true;
}
#endif /* JS_HAS_TEMPORAL_API */
static const JSFunctionSpec date_static_methods[] = {
JS_FN("UTC", date_UTC, 7, 0),
JS_FN("parse", date_parse, 1, 0),
JS_FN("now", date_now, 0, 0),
JS_FS_END,
};
static const JSFunctionSpec date_methods[] = {
JS_INLINABLE_FN("getTime", date_getTime, 0, 0, DateGetTime),
JS_FN("getTimezoneOffset", date_getTimezoneOffset, 0, 0),
JS_FN("getYear", date_getYear, 0, 0),
JS_INLINABLE_FN("getFullYear", date_getFullYear, 0, 0, DateGetFullYear),
JS_FN("getUTCFullYear", date_getUTCFullYear, 0, 0),
JS_INLINABLE_FN("getMonth", date_getMonth, 0, 0, DateGetMonth),
JS_FN("getUTCMonth", date_getUTCMonth, 0, 0),
JS_INLINABLE_FN("getDate", date_getDate, 0, 0, DateGetDate),
JS_FN("getUTCDate", date_getUTCDate, 0, 0),
JS_INLINABLE_FN("getDay", date_getDay, 0, 0, DateGetDay),
JS_FN("getUTCDay", date_getUTCDay, 0, 0),
JS_INLINABLE_FN("getHours", date_getHours, 0, 0, DateGetHours),
JS_FN("getUTCHours", date_getUTCHours, 0, 0),
JS_INLINABLE_FN("getMinutes", date_getMinutes, 0, 0, DateGetMinutes),
JS_FN("getUTCMinutes", date_getUTCMinutes, 0, 0),
JS_INLINABLE_FN("getSeconds", date_getSeconds, 0, 0, DateGetSeconds),
JS_FN("getUTCSeconds", date_getUTCSeconds, 0, 0),
JS_FN("getMilliseconds", date_getMilliseconds, 0, 0),
JS_FN("getUTCMilliseconds", date_getUTCMilliseconds, 0, 0),
JS_FN("setTime", date_setTime, 1, 0),
JS_FN("setYear", date_setYear, 1, 0),
JS_FN("setFullYear", date_setFullYear, 3, 0),
JS_FN("setUTCFullYear", date_setUTCFullYear, 3, 0),
JS_FN("setMonth", date_setMonth, 2, 0),
JS_FN("setUTCMonth", date_setUTCMonth, 2, 0),
JS_FN("setDate", date_setDate, 1, 0),
JS_FN("setUTCDate", date_setUTCDate, 1, 0),
JS_FN("setHours", date_setHours, 4, 0),
JS_FN("setUTCHours", date_setUTCHours, 4, 0),
JS_FN("setMinutes", date_setMinutes, 3, 0),
JS_FN("setUTCMinutes", date_setUTCMinutes, 3, 0),
JS_FN("setSeconds", date_setSeconds, 2, 0),
JS_FN("setUTCSeconds", date_setUTCSeconds, 2, 0),
JS_FN("setMilliseconds", date_setMilliseconds, 1, 0),
JS_FN("setUTCMilliseconds", date_setUTCMilliseconds, 1, 0),
JS_FN("toUTCString", date_toUTCString, 0, 0),
#if JS_HAS_TEMPORAL_API
JS_FN("toTemporalInstant", date_toTemporalInstant, 0, 0),
#endif
#if JS_HAS_INTL_API
JS_SELF_HOSTED_FN("toLocaleString", "Date_toLocaleString", 0, 0),
JS_SELF_HOSTED_FN("toLocaleDateString", "Date_toLocaleDateString", 0, 0),
JS_SELF_HOSTED_FN("toLocaleTimeString", "Date_toLocaleTimeString", 0, 0),
#else
JS_FN("toLocaleString", date_toLocaleString, 0, 0),
JS_FN("toLocaleDateString", date_toLocaleDateString, 0, 0),
JS_FN("toLocaleTimeString", date_toLocaleTimeString, 0, 0),
#endif
JS_FN("toDateString", date_toDateString, 0, 0),
JS_FN("toTimeString", date_toTimeString, 0, 0),
JS_FN("toISOString", date_toISOString, 0, 0),
JS_FN("toJSON", date_toJSON, 1, 0),
JS_FN("toSource", date_toSource, 0, 0),
JS_FN("toString", date_toString, 0, 0),
JS_INLINABLE_FN("valueOf", date_valueOf, 0, 0, DateGetTime),
JS_SYM_FN(toPrimitive, date_toPrimitive, 1, JSPROP_READONLY),
JS_FS_END,
};
static bool NewDateObject(JSContext* cx, const CallArgs& args, ClippedTime t) {
MOZ_ASSERT(args.isConstructing());
RootedObject proto(cx);
if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_Date, &proto)) {
return false;
}
JSObject* obj = NewDateObjectMsec(cx, t, proto);
if (!obj) {
return false;
}
args.rval().setObject(*obj);
return true;
}
/**
* 21.4.4.41.4 ToDateString ( tv )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool ToDateString(JSContext* cx, const CallArgs& args, ClippedTime t) {
const char* locale = cx->realm()->getLocale();
if (!locale) {
return false;
}
return FormatDate(cx, ForceUTC(cx->realm()), locale, t.toDouble(),
FormatSpec::DateTime, args.rval());
}
/**
* 21.4.2.1 Date ( ...values )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool DateNoArguments(JSContext* cx, const CallArgs& args) {
MOZ_ASSERT(args.isConstructing());
MOZ_ASSERT(args.length() == 0);
// Step 3.
ClippedTime now = NowAsMillis(cx);
// Steps 6-8.
return NewDateObject(cx, args, now);
}
/**
* 21.4.2.1 Date ( ...values )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool DateOneArgument(JSContext* cx, const CallArgs& args) {
MOZ_ASSERT(args.isConstructing());
MOZ_ASSERT(args.length() == 1);
// Step 4.a.
MutableHandle<Value> value = args[0];
// Step 4.b.
if (value.isObject()) {
RootedObject obj(cx, &value.toObject());
ESClass cls;
if (!GetBuiltinClass(cx, obj, &cls)) {
return false;
}
if (cls == ESClass::Date) {
RootedValue unboxed(cx);
if (!Unbox(cx, obj, &unboxed)) {
return false;
}
// Steps 6-8.
return NewDateObject(cx, args, TimeClip(unboxed.toNumber()));
}
}
// Step 4.c.i.
if (!ToPrimitive(cx, value)) {
return false;
}
// Steps 4.c.ii-iii.
ClippedTime t;
if (value.isString()) {
JSLinearString* linearStr = value.toString()->ensureLinear(cx);
if (!linearStr) {
return false;
}
if (!ParseDate(ForceUTC(cx->realm()), linearStr, &t)) {
t = ClippedTime::invalid();
}
} else {
double d;
if (!ToNumber(cx, value, &d)) {
return false;
}
t = TimeClip(d);
}
// Steps 6-8.
return NewDateObject(cx, args, t);
}
/**
* 21.4.2.1 Date ( ...values )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool DateMultipleArguments(JSContext* cx, const CallArgs& args) {
// Step 5.a.
MOZ_ASSERT(args.isConstructing());
MOZ_ASSERT(args.length() >= 2);
// Step 5.b.
double y;
if (!ToNumber(cx, args[0], &y)) {
return false;
}
// Step 5.c.
double m;
if (!ToNumber(cx, args[1], &m)) {
return false;
}
// Step 5.d.
double dt;
if (args.length() >= 3) {
if (!ToNumber(cx, args[2], &dt)) {
return false;
}
} else {
dt = 1;
}
// Step 5.e.
double h;
if (args.length() >= 4) {
if (!ToNumber(cx, args[3], &h)) {
return false;
}
} else {
h = 0;
}
// Step 5.f.
double min;
if (args.length() >= 5) {
if (!ToNumber(cx, args[4], &min)) {
return false;
}
} else {
min = 0;
}
// Step 5.g.
double s;
if (args.length() >= 6) {
if (!ToNumber(cx, args[5], &s)) {
return false;
}
} else {
s = 0;
}
// Step 5.h.
double milli;
if (args.length() >= 7) {
if (!ToNumber(cx, args[6], &milli)) {
return false;
}
} else {
milli = 0;
}
// Step 5.i.
double yr = MakeFullYear(y);
// Step 5.j.
double finalDate = MakeDate(MakeDay(yr, m, dt), MakeTime(h, min, s, milli));
// Steps 5.k and 6-8.
return NewDateObject(cx, args,
TimeClip(UTC(ForceUTC(cx->realm()), finalDate)));
}
/**
* 21.4.2.1 Date ( ...values )
*
* ES2025 draft rev 76814cbd5d7842c2a99d28e6e8c7833f1de5bee0
*/
static bool DateConstructor(JSContext* cx, unsigned argc, Value* vp) {
AutoJSConstructorProfilerEntry pseudoFrame(cx, "Date");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1.
if (!args.isConstructing()) {
return ToDateString(cx, args, NowAsMillis(cx));
}
// Step 2.
unsigned numberOfArgs = args.length();
// Steps 3 and 6-8.
if (numberOfArgs == 0) {
return DateNoArguments(cx, args);
}
// Steps 4 and 6-8.
if (numberOfArgs == 1) {
return DateOneArgument(cx, args);
}
// Steps 5-8.
return DateMultipleArguments(cx, args);
}
static bool FinishDateClassInit(JSContext* cx, HandleObject ctor,
HandleObject proto) {
/*
* Date.prototype.toGMTString has the same initial value as
* Date.prototype.toUTCString.
*/
RootedValue toUTCStringFun(cx);
RootedId toUTCStringId(cx, NameToId(cx->names().toUTCString));
RootedId toGMTStringId(cx, NameToId(cx->names().toGMTString));
return NativeGetProperty(cx, proto.as<NativeObject>(), toUTCStringId,
&toUTCStringFun) &&
NativeDefineDataProperty(cx, proto.as<NativeObject>(), toGMTStringId,
toUTCStringFun, 0);
}
static const ClassSpec DateObjectClassSpec = {
GenericCreateConstructor<DateConstructor, 7, gc::AllocKind::FUNCTION>,
GenericCreatePrototype<DateObject>,
date_static_methods,
nullptr,
date_methods,
nullptr,
FinishDateClassInit,
};
const JSClass DateObject::class_ = {
"Date",
JSCLASS_HAS_RESERVED_SLOTS(RESERVED_SLOTS) |
JSCLASS_HAS_CACHED_PROTO(JSProto_Date),
JS_NULL_CLASS_OPS,
&DateObjectClassSpec,
};
const JSClass DateObject::protoClass_ = {
"Date.prototype",
JSCLASS_HAS_CACHED_PROTO(JSProto_Date),
JS_NULL_CLASS_OPS,
&DateObjectClassSpec,
};
JSObject* js::NewDateObjectMsec(JSContext* cx, ClippedTime t,
HandleObject proto /* = nullptr */) {
DateObject* obj = NewObjectWithClassProto<DateObject>(cx, proto);
if (!obj) {
return nullptr;
}
obj->setUTCTime(t);
return obj;
}
JS_PUBLIC_API JSObject* JS::NewDateObject(JSContext* cx, ClippedTime time) {
AssertHeapIsIdle();
CHECK_THREAD(cx);
return NewDateObjectMsec(cx, time);
}
JS_PUBLIC_API JSObject* js::NewDateObject(JSContext* cx, int year, int mon,
int mday, int hour, int min,
int sec) {
MOZ_ASSERT(mon < 12);
double msec_time =
MakeDate(MakeDay(year, mon, mday), MakeTime(hour, min, sec, 0.0));
return NewDateObjectMsec(cx, TimeClip(UTC(ForceUTC(cx->realm()), msec_time)));
}
JS_PUBLIC_API bool js::DateIsValid(JSContext* cx, HandleObject obj,
bool* isValid) {
ESClass cls;
if (!GetBuiltinClass(cx, obj, &cls)) {
return false;
}
if (cls != ESClass::Date) {
*isValid = false;
return true;
}
RootedValue unboxed(cx);
if (!Unbox(cx, obj, &unboxed)) {
return false;
}
*isValid = !std::isnan(unboxed.toNumber());
return true;
}
JS_PUBLIC_API JSObject* JS::NewDateObject(JSContext* cx, int year, int mon,
int mday, int hour, int min,
int sec) {
AssertHeapIsIdle();
CHECK_THREAD(cx);
return js::NewDateObject(cx, year, mon, mday, hour, min, sec);
}
JS_PUBLIC_API bool JS::ObjectIsDate(JSContext* cx, Handle<JSObject*> obj,
bool* isDate) {
cx->check(obj);
ESClass cls;
if (!GetBuiltinClass(cx, obj, &cls)) {
return false;
}
*isDate = cls == ESClass::Date;
return true;
}
JS_PUBLIC_API bool js::DateGetMsecSinceEpoch(JSContext* cx, HandleObject obj,
double* msecsSinceEpoch) {
ESClass cls;
if (!GetBuiltinClass(cx, obj, &cls)) {
return false;
}
if (cls != ESClass::Date) {
*msecsSinceEpoch = 0;
return true;
}
RootedValue unboxed(cx);
if (!Unbox(cx, obj, &unboxed)) {
return false;
}
*msecsSinceEpoch = unboxed.toNumber();
return true;
}
JS_PUBLIC_API bool JS::IsISOStyleDate(JSContext* cx,
const JS::Latin1Chars& str) {
ClippedTime result;
return ParseISOStyleDate(ForceUTC(cx->realm()), str.begin().get(),
str.length(), &result);
}