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-rw-r--r--src/corelib/time/qdatetime.cpp98
1 files changed, 62 insertions, 36 deletions
diff --git a/src/corelib/time/qdatetime.cpp b/src/corelib/time/qdatetime.cpp
index a9fc47e053..95a7255a04 100644
--- a/src/corelib/time/qdatetime.cpp
+++ b/src/corelib/time/qdatetime.cpp
@@ -1465,7 +1465,7 @@ QDate QDate::addMonths(int nmonths, QCalendar cal) const
}
/*!
- \override
+ \overload
*/
QDate QDate::addMonths(int nmonths) const
@@ -1530,7 +1530,7 @@ QDate QDate::addYears(int nyears, QCalendar cal) const
}
/*!
- \override
+ \overload
*/
QDate QDate::addYears(int nyears) const
@@ -3432,15 +3432,15 @@ inline qint64 QDateTimePrivate::zoneMSecsToEpochMSecs(qint64 zoneMSecs, const QT
datetime by adding a number of seconds, days, months, or years.
QDateTime can describe datetimes with respect to \l{Qt::LocalTime}{local
- time}, to \l{Qt::UTC}{UTC}, to a specified \l{Qt::OffsetFromUTC}{offset
- from UTC} or to a specified \l{Qt::TimeZone}{time zone}, in conjunction
- with the QTimeZone class. For example, a time zone of "Europe/Berlin" will
- apply the daylight-saving rules as used in Germany since 1970. In contrast,
- an offset from UTC of +3600 seconds is one hour ahead of UTC (usually
- written in ISO standard notation as "UTC+01:00"), with no daylight-saving
- offset or changes. When using either local time or a specified time zone,
- time-zone transitions such as the starts and ends of daylight-saving time
- (DST) are taken into account. The choice of system used to represent a
+ time}, to \l{Qt::UTC}{UTC}, to a specified \l{Qt::OffsetFromUTC}{offset from
+ UTC} or to a specified \l{Qt::TimeZone}{time zone}, in conjunction with the
+ QTimeZone class. For example, a time zone of "Europe/Berlin" will apply the
+ daylight-saving rules as used in Germany since 1970. In contrast, an offset
+ from UTC of +3600 seconds is one hour ahead of UTC (usually written in ISO
+ standard notation as "UTC+01:00"), with no daylight-saving offset or
+ changes. When using either local time or a specified time zone, time-zone
+ transitions such as the starts and ends of daylight-saving time (DST; but
+ see below) are taken into account. The choice of system used to represent a
datetime is described as its "timespec".
A QDateTime object is typically created either by giving a date and time
@@ -3528,11 +3528,13 @@ inline qint64 QDateTimePrivate::zoneMSecsToEpochMSecs(qint64 zoneMSecs, const QT
The range of valid dates taking DST into account is 1970-01-01 to the
present, and rules are in place for handling DST correctly until 2037-12-31,
- but these could change. For dates falling outside that range, QDateTime
- makes a \e{best guess} using the rules for year 1970 or 2037, but we can't
- guarantee accuracy. This means QDateTime doesn't take into account changes
- in a time zone before 1970, even if the system's time zone database provides
- that information.
+ but these could change. For dates after 2037, QDateTime makes a \e{best
+ guess} using the rules for year 2037, but we can't guarantee accuracy;
+ indeed, for \e{any} future date, the time-zone may change its rules before
+ that date comes around. For dates before 1970, QDateTime doesn't take DST
+ changes into account, even if the system's time zone database provides that
+ information, although it does take into account changes to the time-zone's
+ standard offset, where this information is available.
\section2 Offsets From UTC
@@ -3546,6 +3548,7 @@ inline qint64 QDateTimePrivate::zoneMSecsToEpochMSecs(qint64 zoneMSecs, const QT
*/
/*!
+ \since 5.14
\enum QDateTime::YearRange
This enumerated type describes the range of years (in the Gregorian
@@ -3797,17 +3800,22 @@ QTimeZone QDateTime::timeZone() const
/*!
\since 5.2
- Returns the current Offset From UTC in seconds.
+ Returns this date-time's Offset From UTC in seconds.
- If the timeSpec() is Qt::OffsetFromUTC this will be the value originally set.
-
- If the timeSpec() is Qt::TimeZone this will be the offset effective in the
- Time Zone including any Daylight-Saving Offset.
-
- If the timeSpec() is Qt::LocalTime this will be the difference between the
- Local Time and UTC including any Daylight-Saving Offset.
+ The result depends on timeSpec():
+ \list
+ \li \c Qt::UTC The offset is 0.
+ \li \c Qt::OffsetFromUTC The offset is the value originally set.
+ \li \c Qt::LocalTime The local time's offset from UTC is returned.
+ \li \c Qt::TimeZone The offset used by the time-zone is returned.
+ \endlist
- If the timeSpec() is Qt::UTC this will be 0.
+ For the last two, the offset at this date and time will be returned, taking
+ account of Daylight-Saving Offset unless the date precedes the start of
+ 1970. The offset is the difference between the local time or time in the
+ given time-zone and UTC time; it is positive in time-zones ahead of UTC
+ (East of The Prime Meridian), negative for those behind UTC (West of The
+ Prime Meridian).
\sa setOffsetFromUtc()
*/
@@ -3853,6 +3861,9 @@ int QDateTime::offsetFromUtc() const
QString QDateTime::timeZoneAbbreviation() const
{
+ if (!isValid())
+ return QString();
+
switch (getSpec(d)) {
case Qt::UTC:
return QLatin1String("UTC");
@@ -3887,6 +3898,9 @@ QString QDateTime::timeZoneAbbreviation() const
bool QDateTime::isDaylightTime() const
{
+ if (!isValid())
+ return false;
+
switch (getSpec(d)) {
case Qt::UTC:
case Qt::OffsetFromUTC:
@@ -4753,17 +4767,24 @@ QDateTime QDateTime::toTimeZone(const QTimeZone &timeZone) const
Returns \c true if this datetime is equal to the \a other datetime;
otherwise returns \c false.
+ Since 5.14, all invalid datetimes are equal to one another and differ from
+ all other datetimes.
+
\sa operator!=()
*/
bool QDateTime::operator==(const QDateTime &other) const
{
- if (getSpec(d) == Qt::LocalTime
- && getStatus(d) == getStatus(other.d)) {
+ if (!isValid())
+ return !other.isValid();
+ if (!other.isValid())
+ return false;
+
+ if (getSpec(d) == Qt::LocalTime && getStatus(d) == getStatus(other.d))
return getMSecs(d) == getMSecs(other.d);
- }
+
// Convert to UTC and compare
- return (toMSecsSinceEpoch() == other.toMSecsSinceEpoch());
+ return toMSecsSinceEpoch() == other.toMSecsSinceEpoch();
}
/*!
@@ -4772,8 +4793,9 @@ bool QDateTime::operator==(const QDateTime &other) const
Returns \c true if this datetime is different from the \a other
datetime; otherwise returns \c false.
- Two datetimes are different if either the date, the time, or the
- time zone components are different.
+ Two datetimes are different if either the date, the time, or the time zone
+ components are different. Since 5.14, any invalid datetime is less than all
+ valid datetimes.
\sa operator==()
*/
@@ -4785,12 +4807,16 @@ bool QDateTime::operator==(const QDateTime &other) const
bool QDateTime::operator<(const QDateTime &other) const
{
- if (getSpec(d) == Qt::LocalTime
- && getStatus(d) == getStatus(other.d)) {
+ if (!isValid())
+ return other.isValid();
+ if (!other.isValid())
+ return false;
+
+ if (getSpec(d) == Qt::LocalTime && getStatus(d) == getStatus(other.d))
return getMSecs(d) < getMSecs(other.d);
- }
+
// Convert to UTC and compare
- return (toMSecsSinceEpoch() < other.toMSecsSinceEpoch());
+ return toMSecsSinceEpoch() < other.toMSecsSinceEpoch();
}
/*!
@@ -5841,7 +5867,7 @@ uint qHash(const QDateTime &key, uint seed)
// QDate/QTime/spec/offset because QDateTime::operator== converts both arguments
// to the same timezone. If we don't, qHash would return different hashes for
// two QDateTimes that are equivalent once converted to the same timezone.
- return qHash(key.toMSecsSinceEpoch(), seed);
+ return key.isValid() ? qHash(key.toMSecsSinceEpoch(), seed) : seed;
}
/*! \fn uint qHash(const QDate &key, uint seed = 0)