Cbor: Add overloads for QStringView

Change-Id: I8d22d0741c4d3852b438b12099f81ed87244871d
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/serialization/qcborvalue.cpp

@@ -915,7 +915,7 @@ void QCborContainerPrivate::replaceAt_complex(Element &e, const QCborValue &valu
 // in qstring.cpp
 void qt_to_latin1_unchecked(uchar *dst, const ushort *uc, qsizetype len);
 
-Q_NEVER_INLINE void QCborContainerPrivate::appendAsciiString(const QString &s)
+Q_NEVER_INLINE void QCborContainerPrivate::appendAsciiString(QStringView s)
 {
     qsizetype len = s.size();
     QtCbor::Element e;
@@ -926,7 +926,7 @@ Q_NEVER_INLINE void QCborContainerPrivate::appendAsciiString(const QString &s)
 
     char *ptr = data.data() + e.value + sizeof(ByteData);
     uchar *l = reinterpret_cast<uchar *>(ptr);
-    const ushort *uc = (const ushort *)s.unicode();
+    const ushort *uc = (const ushort *)s.utf16();
     qt_to_latin1_unchecked(l, uc, len);
 }
 
@@ -1646,13 +1646,23 @@ QCborValue::QCborValue(const QByteArray &ba)
     container->ref.storeRelaxed(1);
 }
 
+#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Creates a QCborValue with string value \a s. The value can later be
     retrieved using toString().
 
     \sa toString(), isString(), isByteArray()
  */
-QCborValue::QCborValue(const QString &s)
+QCborValue::QCborValue(const QString &s) : QCborValue(qToStringViewIgnoringNull(s)) {}
+#endif
+
+/*!
+    Creates a QCborValue with string value \a s. The value can later be
+    retrieved using toString().
+
+    \sa toString(), isString(), isByteArray()
+*/
+QCborValue::QCborValue(QStringView s)
     : n(0), container(new QCborContainerPrivate), t(String)
 {
     container->append(s);

src/corelib/serialization/qcborvalue.h

@@ -143,7 +143,10 @@ public:
     QCborValue(QCborSimpleType st) : t(type_helper(st)) {}
 
     QCborValue(const QByteArray &ba);
+#if QT_STRINGVIEW_LEVEL < 2
     QCborValue(const QString &s);
+#endif
+    QCborValue(QStringView s);
     QCborValue(QLatin1String s);
 #ifndef QT_NO_CAST_FROM_ASCII
     QT_ASCII_CAST_WARN QCborValue(const char *s) : QCborValue(QString::fromUtf8(s)) {}

src/corelib/serialization/qcborvalue_p.h

@@ -245,13 +245,21 @@ public:
         appendByteData(s.latin1(), s.size(), QCborValue::String,
                        QtCbor::Element::StringIsAscii);
     }
-    void appendAsciiString(const QString &s);
+    void appendAsciiString(QStringView s);
+
+#if QT_STRINGVIEW_LEVEL < 2
     void append(const QString &s)
+    {
+        append(qToStringViewIgnoringNull(s));
+    }
+#endif
+
+    void append(QStringView s)
     {
         if (QtPrivate::isAscii(s))
             appendAsciiString(s);
         else
-            appendByteData(reinterpret_cast<const char *>(s.constData()), s.size() * 2,
+            appendByteData(reinterpret_cast<const char *>(s.utf16()), s.size() * 2,
                            QCborValue::String, QtCbor::Element::StringIsUtf16);
     }
     void append(const QCborValue &v)
@@ -345,33 +353,41 @@ public:
         return e;
     }
 
-    bool stringEqualsElement(qsizetype idx, QLatin1String s) const
+    static int compareUtf8(const QtCbor::ByteData *b, const QLatin1String &s)
     {
-        const auto &e = elements.at(idx);
-        if (e.type != QCborValue::String)
-            return false;
-
-        const QtCbor::ByteData *b = byteData(idx);
-        if (!b)
-            return s.isEmpty();
-
-        if (e.flags & QtCbor::Element::StringIsUtf16)
-            return QtPrivate::compareStrings(b->asStringView(), s) == 0;
-        return QUtf8::compareUtf8(b->byte(), b->len, s) == 0;
+        return QUtf8::compareUtf8(b->byte(), b->len, s);
     }
-    bool stringEqualsElement(qsizetype idx, const QString &s) const
-    {
-        const auto &e = elements.at(idx);
-        if (e.type != QCborValue::String)
-            return false;
 
-        const QtCbor::ByteData *b = byteData(idx);
+    static int compareUtf8(const QtCbor::ByteData *b, QStringView s)
+    {
+        return QUtf8::compareUtf8(b->byte(), b->len, s.data(), s.size());
+    }
+
+    template<typename String>
+    int stringCompareElement(const QtCbor::Element &e, String s) const
+    {
+        if (e.type != QCborValue::String)
+            return int(e.type) - int(QCborValue::String);
+
+        const QtCbor::ByteData *b = byteData(e);
         if (!b)
-            return s.isEmpty();
+            return s.isEmpty() ? 0 : -1;
 
         if (e.flags & QtCbor::Element::StringIsUtf16)
-            return QtPrivate::compareStrings(b->asStringView(), s) == 0;
-        return QUtf8::compareUtf8(b->byte(), b->len, s.data(), s.size()) == 0;
+            return QtPrivate::compareStrings(b->asStringView(), s);
+        return compareUtf8(b, s);
+    }
+
+    template<typename String>
+    bool stringEqualsElement(const QtCbor::Element &e, String s) const
+    {
+        return stringCompareElement(e, s) == 0;
+    }
+
+    template<typename String>
+    bool stringEqualsElement(qsizetype idx, String s) const
+    {
+        return stringEqualsElement(elements.at(idx), s);
     }
 
     static int compareElement_helper(const QCborContainerPrivate *c1, QtCbor::Element e1,