QDateTimeEdit: fix setDate() if time is in a spring-forward

If the time the widget is set to use falls in the gap skipped by a
spring-forward, setting the date to the day of the spring-forward
turned a valid date into an invalid date-time.  So use the usual trick
to map the "draft" date-time to a valid one.

Fixes: QTBUG-64485
Fixes: QTBUG-58947
Change-Id: Ib8f0f092cd5d6dce3da31eb52cd42150ca0d1fcb
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 7 insertions, 1 deletions

diff --git a/src/widgets/widgets/qdatetimeedit.cpp b/src/widgets/widgets/qdatetimeedit.cpp
index fca81bec48..68bfd175ff 100644
--- a/src/widgets/widgets/qdatetimeedit.cpp
+++ b/src/widgets/widgets/qdatetimeedit.cpp
@@ -273,7 +273,13 @@ void QDateTimeEdit::setDate(const QDate &date)
             setDateRange(date, date);
 
         d->clearCache();
-        d->setValue(QDateTime(date, d->value.toTime(), d->spec), EmitIfChanged);
+        QDateTime when(date, d->value.toTime(), d->spec);
+        // The specified time might not exist on the specified day,
+        // i.e. the time is in the gap a spring-forward jumps over.
+        if (!when.isValid())
+            when = QDateTime::fromMSecsSinceEpoch(when.toMSecsSinceEpoch(), d->spec);
+        Q_ASSERT(when.isValid());
+        d->setValue(when, EmitIfChanged);
         d->updateTimeSpec();
     }
 }