QTextStream: fix streaming of char16_t's

Clazy complains about all uses of QLatin1Char these days, but if one
actually applies the fixit to turn

   out << QLatin1Char(' ');

into

   out << u' ';

the space is now streamed as an int (20), not as a space.

Fix by providing an explicit char16_t overload.

[ChangeLog][QtCore][QTextStream] Added op<<(char16_t).

[ChangeLog][Important Behavior Changes] QTextStream streams char16_t's
as QChars now instead of outputting the numeric value. If you want to
preserve the old behavior, cast the char16_t to a numeric type, such
as ushort or int, and stream that. This is backwards-compatible.

Pick-to: 6.3
Change-Id: I42d422cdebb27d38ac1714b22ef186642ec407e7
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/auto/corelib/serialization/qtextstream/tst_qtextstream.cpp b/tests/auto/corelib/serialization/qtextstream/tst_qtextstream.cpp
index 9e8bcfaea2..5a7be18823 100644
--- a/tests/auto/corelib/serialization/qtextstream/tst_qtextstream.cpp
+++ b/tests/auto/corelib/serialization/qtextstream/tst_qtextstream.cpp
@@ -94,6 +94,8 @@ private slots:
     // char operators
     void QChar_operators_FromDevice_data();
     void QChar_operators_FromDevice();
+    void char16_t_operators_FromDevice_data();
+    void char16_t_operators_FromDevice();
     void char_operators_FromDevice_data();
     void char_operators_FromDevice();
 
@@ -1919,6 +1921,31 @@ void tst_QTextStream::QChar_operators_FromDevice()
 }
 
 // ------------------------------------------------------------------------------
+void tst_QTextStream::char16_t_operators_FromDevice_data()
+{
+    generateOperatorCharData(false);
+}
+
+// ------------------------------------------------------------------------------
+void tst_QTextStream::char16_t_operators_FromDevice()
+{
+    QFETCH(const QChar, qchar_output);
+    QFETCH(const QByteArray, write_output);
+    const char16_t char16_t_output = qchar_output.unicode();
+
+    QBuffer writeBuf;
+    writeBuf.open(QBuffer::WriteOnly);
+
+    QTextStream writeStream(&writeBuf);
+    writeStream.setEncoding(QStringConverter::Latin1);
+    writeStream << char16_t_output;
+    writeStream.flush();
+
+    QCOMPARE(writeBuf.buffer().size(), write_output.size());
+    QCOMPARE(writeBuf.buffer().constData(), write_output.constData());
+}
+
+// ------------------------------------------------------------------------------
 void tst_QTextStream::char_operators_FromDevice_data()
 {
     generateOperatorCharData(false);