QtBase: eradicate QT_STRINGVIEW_LEVEL uses

It's not used and not useful.

The macro itself has to stay, for now, because Qt5Compat uses it, too.

Task-number: QTBUG-100861
Pick-to: 6.4 6.3 6.2
Change-Id: I5d0557a6c959d6facf6e47f26786a9d365339e95
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

21 files changed, 2 insertions, 130 deletions

diff --git a/src/corelib/io/qdebug.h b/src/corelib/io/qdebug.h
index 22328e7c85..64b4ac37c9 100644
--- a/src/corelib/io/qdebug.h
+++ b/src/corelib/io/qdebug.h
@@ -110,9 +110,7 @@ public:
     inline QDebug &operator<<(double t) { stream->ts << t; return maybeSpace(); }
     inline QDebug &operator<<(const char* t) { stream->ts << QString::fromUtf8(t); return maybeSpace(); }
     inline QDebug &operator<<(const char16_t *t)  { stream->ts << QStringView(t); return maybeSpace(); }
-#if QT_STRINGVIEW_LEVEL < 2
     inline QDebug &operator<<(const QString & t) { putString(t.constData(), uint(t.length())); return maybeSpace(); }
-#endif
     inline QDebug &operator<<(QStringView s) { putString(s.data(), size_t(s.size())); return maybeSpace(); }
     inline QDebug &operator<<(QUtf8StringView s) { putByteArray(reinterpret_cast<const char*>(s.data()), s.size(), ContainsBinary); return maybeSpace(); }
     inline QDebug &operator<<(QLatin1StringView t) { putByteArray(t.latin1(), t.size(), ContainsLatin1); return maybeSpace(); }
diff --git a/src/corelib/serialization/qcborvalue.cpp b/src/corelib/serialization/qcborvalue.cpp
index d233c1b01e..056e8c07b6 100644
--- a/src/corelib/serialization/qcborvalue.cpp
+++ b/src/corelib/serialization/qcborvalue.cpp
@@ -1715,7 +1715,6 @@ 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().
@@ -1723,7 +1722,6 @@ QCborValue::QCborValue(const QByteArray &ba)
     \sa toString(), isString(), isByteArray()
  */
 QCborValue::QCborValue(const QString &s) : QCborValue(qToStringViewIgnoringNull(s)) {}
-#endif
 
 /*!
     Creates a QCborValue with string value \a s. The value can later be
diff --git a/src/corelib/serialization/qcborvalue.h b/src/corelib/serialization/qcborvalue.h
index 9f80b5e9bd..a83a36a3d8 100644
--- a/src/corelib/serialization/qcborvalue.h
+++ b/src/corelib/serialization/qcborvalue.h
@@ -110,9 +110,7 @@ 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(QLatin1StringView s);
 #ifndef QT_NO_CAST_FROM_ASCII
diff --git a/src/corelib/serialization/qcborvalue_p.h b/src/corelib/serialization/qcborvalue_p.h
index 4e2bb425db..c5cc6c6f0b 100644
--- a/src/corelib/serialization/qcborvalue_p.h
+++ b/src/corelib/serialization/qcborvalue_p.h
@@ -225,12 +225,10 @@ public:
     }
     void appendAsciiString(QStringView s);
 
-#if QT_STRINGVIEW_LEVEL < 2
     void append(const QString &s)
     {
         append(qToStringViewIgnoringNull(s));
     }
-#endif
 
     void append(QStringView s)
     {
diff --git a/src/corelib/serialization/qjsondocument.cpp b/src/corelib/serialization/qjsondocument.cpp
index 59ce496d1b..814033610f 100644
--- a/src/corelib/serialization/qjsondocument.cpp
+++ b/src/corelib/serialization/qjsondocument.cpp
@@ -391,7 +391,6 @@ void QJsonDocument::setArray(const QJsonArray &array)
     d->value = QCborValue::fromJsonValue(array);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a QJsonValue representing the value for the key \a key.
 
@@ -408,7 +407,6 @@ const QJsonValue QJsonDocument::operator[](const QString &key) const
 {
     return (*this)[QStringView(key)];
 }
-#endif
 
 /*!
     \overload
diff --git a/src/corelib/serialization/qjsondocument.h b/src/corelib/serialization/qjsondocument.h
index 72e1b9a5c2..e580c0122d 100644
--- a/src/corelib/serialization/qjsondocument.h
+++ b/src/corelib/serialization/qjsondocument.h
@@ -94,9 +94,7 @@ public:
     void setObject(const QJsonObject &object);
     void setArray(const QJsonArray &array);
 
-#if QT_STRINGVIEW_LEVEL < 2
     const QJsonValue operator[](const QString &key) const;
-#endif
     const QJsonValue operator[](QStringView key) const;
     const QJsonValue operator[](QLatin1StringView key) const;
     const QJsonValue operator[](qsizetype i) const;
diff --git a/src/corelib/serialization/qjsonobject.cpp b/src/corelib/serialization/qjsonobject.cpp
index a3e5bd695e..0a5bafd1cb 100644
--- a/src/corelib/serialization/qjsonobject.cpp
+++ b/src/corelib/serialization/qjsonobject.cpp
@@ -278,7 +278,6 @@ static qsizetype indexOf(const QExplicitlySharedDataPointer<QCborContainerPrivat
     return it.it - begin.it;
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a QJsonValue representing the value for the key \a key.
 
@@ -290,7 +289,6 @@ QJsonValue QJsonObject::value(const QString &key) const
 {
     return value(QStringView(key));
 }
-#endif
 
 /*!
     \overload
@@ -326,7 +324,6 @@ QJsonValue QJsonObject::valueImpl(T key) const
     return QJsonPrivate::Value::fromTrustedCbor(o->valueAt(i + 1));
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a QJsonValue representing the value for the key \a key.
 
@@ -340,7 +337,6 @@ QJsonValue QJsonObject::operator [](const QString &key) const
 {
     return (*this)[QStringView(key)];
 }
-#endif
 
 /*!
     \fn QJsonValue QJsonObject::operator [](QStringView key) const
@@ -356,7 +352,6 @@ QJsonValue QJsonObject::operator [](const QString &key) const
     \since 5.7
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a reference to the value for \a key. If there is no value with key
     \a key in the object, one is created with a QJsonValue::Null value and then
@@ -374,7 +369,6 @@ QJsonValueRef QJsonObject::operator [](const QString &key)
 {
     return (*this)[QStringView(key)];
 }
-#endif
 
 /*!
     \overload
@@ -414,7 +408,6 @@ QJsonValueRef QJsonObject::atImpl(T key)
     return QJsonValueRef(this, index / 2);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Inserts a new item with the key \a key and a value of \a value.
 
@@ -432,7 +425,6 @@ QJsonObject::iterator QJsonObject::insert(const QString &key, const QJsonValue &
 {
     return insert(QStringView(key), value);
 }
-#endif
 
 /*!
     \overload
@@ -487,7 +479,6 @@ QJsonObject::iterator QJsonObject::insertAt(qsizetype pos, T key, const QJsonVal
     return {this, pos / 2};
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Removes \a key from the object.
 
@@ -497,7 +488,6 @@ void QJsonObject::remove(const QString &key)
 {
     remove(QStringView(key));
 }
-#endif
 
 /*!
     \overload
@@ -534,7 +524,6 @@ void QJsonObject::removeImpl(T key)
     removeAt(index);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Removes \a key from the object.
 
@@ -548,7 +537,6 @@ QJsonValue QJsonObject::take(const QString &key)
 {
     return take(QStringView(key));
 }
-#endif
 
 /*!
     \overload
@@ -588,7 +576,6 @@ QJsonValue QJsonObject::takeImpl(T key)
     return v;
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns \c true if the object contains key \a key.
 
@@ -598,7 +585,6 @@ bool QJsonObject::contains(const QString &key) const
 {
     return contains(QStringView(key));
 }
-#endif
 
 /*!
     \overload
@@ -680,7 +666,6 @@ QJsonObject::iterator QJsonObject::erase(QJsonObject::iterator it)
     return { this, qsizetype(it.item.index) };
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns an iterator pointing to the item with key \a key in the
     map.
@@ -692,7 +677,6 @@ QJsonObject::iterator QJsonObject::find(const QString &key)
 {
     return find(QStringView(key));
 }
-#endif
 
 /*!
     \overload
@@ -726,12 +710,10 @@ QJsonObject::iterator QJsonObject::findImpl(T key)
     return {this, index / 2};
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*! \fn QJsonObject::const_iterator QJsonObject::find(const QString &key) const
 
     \overload
 */
-#endif
 
 /*! \fn QJsonObject::const_iterator QJsonObject::find(QStringView key) const
 
@@ -745,7 +727,6 @@ QJsonObject::iterator QJsonObject::findImpl(T key)
     \since 5.7
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a const iterator pointing to the item with key \a key in the
     map.
@@ -757,7 +738,6 @@ QJsonObject::const_iterator QJsonObject::constFind(const QString &key) const
 {
     return constFind(QStringView(key));
 }
-#endif
 
 /*!
     \overload
diff --git a/src/corelib/serialization/qjsonobject.h b/src/corelib/serialization/qjsonobject.h
index 5d7fb227a7..f5f4d1f47e 100644
--- a/src/corelib/serialization/qjsonobject.h
+++ b/src/corelib/serialization/qjsonobject.h
@@ -52,11 +52,9 @@ public:
     inline qsizetype length() const { return size(); }
     bool isEmpty() const;
 
-#if QT_STRINGVIEW_LEVEL < 2
     QJsonValue value(const QString &key) const;
     QJsonValue operator[] (const QString &key) const;
     QJsonValueRef operator[] (const QString &key);
-#endif
     QJsonValue value(QStringView key) const;
     QJsonValue value(QLatin1StringView key) const;
     QJsonValue operator[] (QStringView key) const { return value(key); }
@@ -64,11 +62,9 @@ public:
     QJsonValueRef operator[] (QStringView key);
     QJsonValueRef operator[] (QLatin1StringView key);
 
-#if QT_STRINGVIEW_LEVEL < 2
     void remove(const QString &key);
     QJsonValue take(const QString &key);
     bool contains(const QString &key) const;
-#endif
     void remove(QStringView key);
     void remove(QLatin1StringView key);
     QJsonValue take(QStringView key);
@@ -219,12 +215,10 @@ public:
     // more Qt
     typedef iterator Iterator;
     typedef const_iterator ConstIterator;
-#if QT_STRINGVIEW_LEVEL < 2
     iterator find(const QString &key);
     const_iterator find(const QString &key) const { return constFind(key); }
     const_iterator constFind(const QString &key) const;
     iterator insert(const QString &key, const QJsonValue &value);
-#endif
     iterator find(QStringView key);
     iterator find(QLatin1StringView key);
     const_iterator find(QStringView key) const { return constFind(key); }
diff --git a/src/corelib/serialization/qjsonvalue.cpp b/src/corelib/serialization/qjsonvalue.cpp
index a92677d19d..ef07dcdc3b 100644
--- a/src/corelib/serialization/qjsonvalue.cpp
+++ b/src/corelib/serialization/qjsonvalue.cpp
@@ -761,7 +761,6 @@ QJsonObject QJsonValue::toObject() const
     return toObject(QJsonObject());
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a QJsonValue representing the value for the key \a key.
 
@@ -778,7 +777,6 @@ const QJsonValue QJsonValue::operator[](const QString &key) const
 {
     return (*this)[QStringView(key)];
 }
-#endif
 
 /*!
     \overload
diff --git a/src/corelib/serialization/qjsonvalue.h b/src/corelib/serialization/qjsonvalue.h
index d8ea5e441e..4bb4930690 100644
--- a/src/corelib/serialization/qjsonvalue.h
+++ b/src/corelib/serialization/qjsonvalue.h
@@ -87,9 +87,7 @@ public:
     QJsonObject toObject() const;
     QJsonObject toObject(const QJsonObject &defaultValue) const;
 
-#if QT_STRINGVIEW_LEVEL < 2
     const QJsonValue operator[](const QString &key) const;
-#endif
     const QJsonValue operator[](QStringView key) const;
     const QJsonValue operator[](QLatin1StringView key) const;
     const QJsonValue operator[](qsizetype i) const;
diff --git a/src/corelib/text/qcollator.cpp b/src/corelib/text/qcollator.cpp
index 20a8f1372e..f21df33af4 100644
--- a/src/corelib/text/qcollator.cpp
+++ b/src/corelib/text/qcollator.cpp
@@ -306,7 +306,7 @@ bool QCollator::ignorePunctuation() const
     Returns an integer less than, equal to, or greater than zero depending on
     whether \a s1 sorts before, with or after \a s2.
 */
-#if QT_STRINGVIEW_LEVEL < 2
+
 /*!
     \fn bool QCollator::operator()(const QString &s1, const QString &s2) const
     \overload
@@ -330,7 +330,6 @@ bool QCollator::ignorePunctuation() const
     Returns an integer less than, equal to, or greater than zero depending on
     whether \a s1 sorts before, with or after \a s2.
 */
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*!
     \since 6.3
diff --git a/src/corelib/text/qcollator.h b/src/corelib/text/qcollator.h
index 315ce43e9b..76a453c6ae 100644
--- a/src/corelib/text/qcollator.h
+++ b/src/corelib/text/qcollator.h
@@ -65,7 +65,6 @@ public:
     void setIgnorePunctuation(bool on);
     bool ignorePunctuation() const;
 
-#if QT_STRINGVIEW_LEVEL < 2
     int compare(const QString &s1, const QString &s2) const
     { return compare(QStringView(s1), QStringView(s2)); }
     int compare(const QChar *s1, int len1, const QChar *s2, int len2) const
@@ -73,7 +72,6 @@ public:
 
     bool operator()(const QString &s1, const QString &s2) const
     { return compare(s1, s2) < 0; }
-#endif
     int compare(QStringView s1, QStringView s2) const;
 
     bool operator()(QStringView s1, QStringView s2) const
diff --git a/src/corelib/text/qlocale.cpp b/src/corelib/text/qlocale.cpp
index 0b229c97b4..536c5c3be5 100644
--- a/src/corelib/text/qlocale.cpp
+++ b/src/corelib/text/qlocale.cpp
@@ -1007,12 +1007,10 @@ QLocale::QLocale(QStringView name)
 {
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn QLocale::QLocale(const QString &name)
     \overload
 */
-#endif
 
 /*!
     Constructs a QLocale object initialized with the default locale.
@@ -1582,7 +1580,6 @@ QString QLocale::scriptToString(QLocale::Script script)
     return QLatin1StringView(script_name_list + script_name_index[script]);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn short QLocale::toShort(const QString &s, bool *ok) const
 
@@ -1745,7 +1742,6 @@ QString QLocale::scriptToString(QLocale::Script script)
 
     \sa toFloat(), toInt(), toString()
 */
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*!
     Returns the short int represented by the localized string \a s.
@@ -1987,7 +1983,6 @@ QString QLocale::toString(qulonglong i) const
     return d->m_data->unsLongLongToString(i, -1, 10, -1, flags);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns a localized string representation of the given \a date in the
     specified \a format.
@@ -2024,7 +2019,6 @@ QString QLocale::toString(QTime time, const QString &format) const
 
     \sa QDateTime::toString(), QDate::toString(), QTime::toString()
 */
-#endif
 
 /*!
     \since 5.14
diff --git a/src/corelib/text/qlocale.h b/src/corelib/text/qlocale.h
index b9880496f1..599cd79232 100644
--- a/src/corelib/text/qlocale.h
+++ b/src/corelib/text/qlocale.h
@@ -891,10 +891,8 @@ public:
     Q_FLAG(DataSizeFormats)
 
     QLocale();
-#if QT_STRINGVIEW_LEVEL < 2
     QT_CORE_INLINE_SINCE(6, 4)
     explicit QLocale(const QString &name);
-#endif
     explicit QLocale(QStringView name);
     QLocale(Language language, Territory territory);
     QLocale(Language language, Script script = AnyScript, Territory territory = AnyTerritory);
@@ -922,7 +920,6 @@ public:
     QString nativeCountryName() const;
 #endif
 
-#if QT_STRINGVIEW_LEVEL < 2
     short toShort(const QString &s, bool *ok = nullptr) const
     { return toShort(qToStringViewIgnoringNull(s), ok); }
     ushort toUShort(const QString &s, bool *ok = nullptr) const
@@ -943,7 +940,6 @@ public:
     { return toFloat(qToStringViewIgnoringNull(s), ok); }
     double toDouble(const QString &s, bool *ok = nullptr) const
     { return toDouble(qToStringViewIgnoringNull(s), ok); }
-#endif
 
     short toShort(QStringView s, bool *ok = nullptr) const;
     ushort toUShort(QStringView s, bool *ok = nullptr) const;
@@ -968,13 +964,11 @@ public:
     QString toString(float f, char format = 'g', int precision = 6) const
     { return toString(double(f), format, precision); }
 
-#if QT_STRINGVIEW_LEVEL < 2
     // (Can't inline first two: passing by value doesn't work when only forward-declared.)
     QString toString(QDate date, const QString &format) const;
     QString toString(QTime time, const QString &format) const;
     QString toString(const QDateTime &dateTime, const QString &format) const
     { return toString(dateTime, qToStringViewIgnoringNull(format)); }
-#endif
     QString toString(QDate date, QStringView format) const;
     QString toString(QTime time, QStringView format) const;
     QString toString(const QDateTime &dateTime, QStringView format) const;
diff --git a/src/corelib/text/qstring.cpp b/src/corelib/text/qstring.cpp
index c569bf627d..1a78c1d0cd 100644
--- a/src/corelib/text/qstring.cpp
+++ b/src/corelib/text/qstring.cpp
@@ -4079,7 +4079,6 @@ QString &QString::replace(QChar c, QLatin1StringView after, Qt::CaseSensitivity
     go through QObject::tr(), for example.
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
   Returns the index position of the first occurrence of the string \a
   str in this string, searching forward from index position \a
@@ -4101,7 +4100,6 @@ qsizetype QString::indexOf(const QString &str, qsizetype from, Qt::CaseSensitivi
 {
     return QtPrivate::findString(QStringView(unicode(), length()), from, QStringView(str.unicode(), str.length()), cs);
 }
-#endif  // QT_STRINGVIEW_LEVEL < 2
 
 /*!
     \fn qsizetype QString::indexOf(QStringView str, qsizetype from, Qt::CaseSensitivity cs) const
@@ -4157,7 +4155,6 @@ qsizetype QString::indexOf(QChar ch, qsizetype from, Qt::CaseSensitivity cs) con
     return qFindChar(QStringView(unicode(), length()), ch, from, cs);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
   Returns the index position of the last occurrence of the string \a
   str in this string, searching backward from index position \a
@@ -4204,7 +4201,6 @@ qsizetype QString::lastIndexOf(const QString &str, qsizetype from, Qt::CaseSensi
   \sa indexOf(), contains(), count()
 */
 
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*!
   \since 4.5
@@ -4496,7 +4492,6 @@ qsizetype QString::count(QStringView str, Qt::CaseSensitivity cs) const
     return QtPrivate::count(*this, str, cs);
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*! \fn bool QString::contains(const QString &str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
 
     Returns \c true if this string contains an occurrence of the string
@@ -4510,7 +4505,6 @@ qsizetype QString::count(QStringView str, Qt::CaseSensitivity cs) const
 
     \sa indexOf(), count()
 */
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*! \fn bool QString::contains(QLatin1StringView str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
     \since 5.3
@@ -5036,7 +5030,6 @@ QString QString::mid(qsizetype position, qsizetype n) const
     \sa endsWith(), first(), last(), sliced(), chop(), truncate()
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns \c true if the string starts with \a s; otherwise returns
     \c false.
@@ -5052,7 +5045,6 @@ bool QString::startsWith(const QString& s, Qt::CaseSensitivity cs) const
 {
     return qt_starts_with_impl(QStringView(*this), QStringView(s), cs);
 }
-#endif
 
 /*!
   \overload startsWith()
@@ -5091,7 +5083,6 @@ bool QString::startsWith(QChar c, Qt::CaseSensitivity cs) const
     \sa endsWith()
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns \c true if the string ends with \a s; otherwise returns
     \c false.
@@ -5107,7 +5098,6 @@ bool QString::endsWith(const QString &s, Qt::CaseSensitivity cs) const
 {
     return qt_ends_with_impl(QStringView(*this), QStringView(s), cs);
 }
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*!
     \fn bool QString::endsWith(QStringView str, Qt::CaseSensitivity cs) const
@@ -6215,7 +6205,6 @@ QString& QString::fill(QChar ch, qsizetype size)
     sensitivity setting \a cs.
 */
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \overload compare()
     \since 4.2
@@ -6231,7 +6220,6 @@ int QString::compare(const QString &other, Qt::CaseSensitivity cs) const noexcep
 {
     return QtPrivate::compareStrings(*this, other, cs);
 }
-#endif
 
 /*!
     \internal
@@ -8108,7 +8096,6 @@ static QString replaceArgEscapes(QStringView s, const ArgEscapeData &d, qsizetyp
     return result;
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
   Returns a copy of this string with the lowest numbered place marker
   replaced by string \a a, i.e., \c %1, \c %2, ..., \c %99.
@@ -8142,7 +8129,6 @@ QString QString::arg(const QString &a, int fieldWidth, QChar fillChar) const
 {
     return arg(qToStringViewIgnoringNull(a), fieldWidth, fillChar);
 }
-#endif // QT_STRINGVIEW_LEVEL < 2
 
 /*!
     \overload
diff --git a/src/corelib/text/qstring.h b/src/corelib/text/qstring.h
index a176cae038..3f15001ff8 100644
--- a/src/corelib/text/qstring.h
+++ b/src/corelib/text/qstring.h
@@ -517,10 +517,8 @@ public:
                 QChar fillChar = u' ') const;
     [[nodiscard]] QString arg(QChar a, int fieldWidth = 0,
                 QChar fillChar = u' ') const;
-#if QT_STRINGVIEW_LEVEL < 2
     [[nodiscard]] QString arg(const QString &a, int fieldWidth = 0,
                 QChar fillChar = u' ') const;
-#endif
     [[nodiscard]] QString arg(QStringView a, int fieldWidth = 0,
                 QChar fillChar = u' ') const;
     [[nodiscard]] QString arg(QLatin1StringView a, int fieldWidth = 0,
@@ -557,9 +555,7 @@ public:
 
     [[nodiscard]] qsizetype indexOf(QChar c, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
     [[nodiscard]] qsizetype indexOf(QLatin1StringView s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#if QT_STRINGVIEW_LEVEL < 2
     [[nodiscard]] qsizetype indexOf(const QString &s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#endif
     [[nodiscard]] qsizetype indexOf(QStringView s, qsizetype from = 0, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return QtPrivate::findString(*this, from, s, cs); }
     [[nodiscard]] qsizetype lastIndexOf(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
@@ -568,11 +564,9 @@ public:
     [[nodiscard]] qsizetype lastIndexOf(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
     { return lastIndexOf(s, size(), cs); }
     [[nodiscard]] qsizetype lastIndexOf(QLatin1StringView s, qsizetype from, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#if QT_STRINGVIEW_LEVEL < 2
     [[nodiscard]] qsizetype lastIndexOf(const QString &s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
     { return lastIndexOf(s, size(), cs); }
     [[nodiscard]] qsizetype lastIndexOf(const QString &s, qsizetype from, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#endif
 
     [[nodiscard]] qsizetype lastIndexOf(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return lastIndexOf(s, size(), cs); }
@@ -580,9 +574,7 @@ public:
     { return QtPrivate::lastIndexOf(*this, from, s, cs); }
 
     [[nodiscard]] inline bool contains(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#if QT_STRINGVIEW_LEVEL < 2
     [[nodiscard]] inline bool contains(const QString &s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#endif
     [[nodiscard]] inline bool contains(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
     [[nodiscard]] inline bool contains(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
     [[nodiscard]] qsizetype count(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
@@ -636,17 +628,13 @@ public:
     { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); return first(size() - n); }
 
 
-#if QT_STRINGVIEW_LEVEL < 2
     bool startsWith(const QString &s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#endif
     [[nodiscard]] bool startsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return QtPrivate::startsWith(*this, s, cs); }
     bool startsWith(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
     bool startsWith(QChar c, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
 
-#if QT_STRINGVIEW_LEVEL < 2
     bool endsWith(const QString &s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
-#endif
     [[nodiscard]] bool endsWith(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return QtPrivate::endsWith(*this, s, cs); }
     bool endsWith(QLatin1StringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
@@ -690,33 +678,25 @@ public:
 
     QString &insert(qsizetype i, QChar c);
     QString &insert(qsizetype i, const QChar *uc, qsizetype len);
-#if QT_STRINGVIEW_LEVEL < 2
     inline QString &insert(qsizetype i, const QString &s) { return insert(i, s.constData(), s.length()); }
-#endif
     inline QString &insert(qsizetype i, QStringView v) { return insert(i, v.data(), v.length()); }
     QString &insert(qsizetype i, QLatin1StringView s);
 
     QString &append(QChar c);
     QString &append(const QChar *uc, qsizetype len);
-#if QT_STRINGVIEW_LEVEL < 2
     QString &append(const QString &s);
-#endif
     inline QString &append(QStringView v) { return append(v.data(), v.length()); }
     QString &append(QLatin1StringView s);
 
     inline QString &prepend(QChar c) { return insert(0, c); }
     inline QString &prepend(const QChar *uc, qsizetype len) { return insert(0, uc, len); }
-#if QT_STRINGVIEW_LEVEL < 2
     inline QString &prepend(const QString &s) { return insert(0, s); }
-#endif
     inline QString &prepend(QStringView v) { return prepend(v.data(), v.length()); }
     inline QString &prepend(QLatin1StringView s) { return insert(0, s); }
 
     inline QString &operator+=(QChar c) { return append(c); }
 
-#if QT_STRINGVIEW_LEVEL < 2
     inline QString &operator+=(const QString &s) { return append(s); }
-#endif
     inline QString &operator+=(QStringView v) { return append(v); }
     inline QString &operator+=(QLatin1StringView s) { return append(s); }
 
@@ -862,9 +842,7 @@ public:
     QString &setUnicode(const QChar *unicode, qsizetype size);
     inline QString &setUtf16(const ushort *utf16, qsizetype size); // ### Qt 7 char16_t
 
-#if QT_STRINGVIEW_LEVEL < 2
     int compare(const QString &s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
-#endif
     int compare(QLatin1StringView other, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
     inline int compare(QStringView s, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept;
     int compare(QChar ch, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
@@ -1395,10 +1373,8 @@ inline QString::const_iterator QString::cend() const
 { return reinterpret_cast<const QChar*>(d.data() + d.size); }
 inline QString::const_iterator QString::constEnd() const
 { return reinterpret_cast<const QChar*>(d.data() + d.size); }
-#if QT_STRINGVIEW_LEVEL < 2
 inline bool QString::contains(const QString &s, Qt::CaseSensitivity cs) const
 { return indexOf(s, 0, cs) != -1; }
-#endif
 inline bool QString::contains(QLatin1StringView s, Qt::CaseSensitivity cs) const
 { return indexOf(s, 0, cs) != -1; }
 inline bool QString::contains(QChar c, Qt::CaseSensitivity cs) const
diff --git a/src/corelib/text/qstringlist.cpp b/src/corelib/text/qstringlist.cpp
index d157270018..8eb730ee02 100644
--- a/src/corelib/text/qstringlist.cpp
+++ b/src/corelib/text/qstringlist.cpp
@@ -240,7 +240,6 @@ void QtPrivate::QStringList_sort(QStringList *that, Qt::CaseSensitivity cs)
 }
 
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn QStringList QStringList::filter(const QString &str, Qt::CaseSensitivity cs) const
 
@@ -260,7 +259,6 @@ void QtPrivate::QStringList_sort(QStringList *that, Qt::CaseSensitivity cs)
 
     \sa contains()
 */
-#endif
 
 /*!
     \fn QStringList QStringList::filter(QStringView str, Qt::CaseSensitivity cs) const
@@ -289,7 +287,6 @@ static bool stringList_contains(const QStringList &stringList, const T &str, Qt:
 }
 
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn bool QStringList::contains(const QString &str, Qt::CaseSensitivity cs) const
 
@@ -299,7 +296,6 @@ static bool stringList_contains(const QStringList &stringList, const T &str, Qt:
 
     \sa indexOf(), lastIndexOf(), QString::contains()
  */
-#endif
 
 /*!
     \fn bool QStringList::contains(QStringView str, Qt::CaseSensitivity cs) const
@@ -354,7 +350,6 @@ QStringList QtPrivate::QStringList_filter(const QStringList *that, const QRegula
 }
 #endif // QT_CONFIG(regularexpression)
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn QStringList &QStringList::replaceInStrings(const QString &before, const QString &after, Qt::CaseSensitivity cs)
 
@@ -382,7 +377,6 @@ QStringList QtPrivate::QStringList_filter(const QStringList *that, const QRegula
     \overload
     \since 5.14
 */
-#endif
 
 /*!
     \fn QStringList &QStringList::replaceInStrings(QStringView before, QStringView after, Qt::CaseSensitivity cs)
@@ -438,7 +432,6 @@ static qsizetype accumulatedSize(const QStringList &list, qsizetype seplen)
     return result;
 }
 
-#if QT_STRINGVIEW_LEVEL < 2
 /*!
     \fn QString QStringList::join(const QString &separator) const
 
@@ -448,7 +441,6 @@ static qsizetype accumulatedSize(const QStringList &list, qsizetype seplen)
 
     \sa QString::split()
 */
-#endif
 
 /*!
     \fn QString QStringList::join(QChar separator) const
diff --git a/src/corelib/text/qstringlist.h b/src/corelib/text/qstringlist.h
index f4502570dd..079f156479 100644
--- a/src/corelib/text/qstringlist.h
+++ b/src/corelib/text/qstringlist.h
@@ -86,7 +86,6 @@ public:
         return *self();
     }
 
-#if QT_STRINGVIEW_LEVEL < 2
     inline QString join(const QString &sep) const
     { return QtPrivate::QStringList_join(self(), sep.constData(), sep.length()); }
     inline QStringList filter(const QString &str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
@@ -106,7 +105,6 @@ public:
         QtPrivate::QStringList_replaceInStrings(self(), before, after, cs);
         return *self();
     }
-#endif
     using QListSpecialMethodsBase<QString>::contains;
     using QListSpecialMethodsBase<QString>::indexOf;
     using QListSpecialMethodsBase<QString>::lastIndexOf;
@@ -116,14 +114,12 @@ public:
     inline bool contains(QStringView str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return QtPrivate::QStringList_contains(self(), str, cs); }
 
-#if QT_STRINGVIEW_LEVEL < 2
     inline bool contains(const QString &str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const noexcept
     { return QtPrivate::QStringList_contains(self(), str, cs); }
     qsizetype indexOf(const QString &str, qsizetype from = 0) const noexcept
     { return indexOf(QStringView(str), from); }
     qsizetype lastIndexOf(const QString &str, qsizetype from = -1) const noexcept
     { return lastIndexOf(QStringView(str), from); }
-#endif
 
 #if QT_CONFIG(regularexpression)
     inline QStringList filter(const QRegularExpression &re) const
diff --git a/src/corelib/text/qstringview.h b/src/corelib/text/qstringview.h
index ba7cb30c5b..3f0812e2e7 100644
--- a/src/corelib/text/qstringview.h
+++ b/src/corelib/text/qstringview.h
@@ -5,14 +5,7 @@
 #define QSTRINGVIEW_H
 
 /*
-    This macro enables three "levels" of QStringView support:
-
-    1. offer QStringView, overload some functions taking QString with
-    QStringView
-
-    2. Obsolete: QStringRef and its overloads have been removed.
-
-    3. like 2, but replace functions taking QString, too.
+    Obsolete.
 */
 #ifndef QT_STRINGVIEW_LEVEL
 #  define QT_STRINGVIEW_LEVEL 1
diff --git a/src/corelib/time/qdatetime.h b/src/corelib/time/qdatetime.h
index 08f0a1a533..58dff850db 100644
--- a/src/corelib/time/qdatetime.h
+++ b/src/corelib/time/qdatetime.h
@@ -114,10 +114,8 @@ public:
 
 #if QT_CONFIG(datestring)
     QString toString(Qt::DateFormat format = Qt::TextDate) const;
-# if QT_STRINGVIEW_LEVEL < 2
     QString toString(const QString &format, QCalendar cal = QCalendar()) const
     { return toString(qToStringViewIgnoringNull(format), cal); }
-# endif
     QString toString(QStringView format, QCalendar cal = QCalendar()) const;
 #endif
     bool setDate(int year, int month, int day); // Gregorian-optimized
@@ -146,13 +144,11 @@ public:
     static QDate fromString(QStringView string, QStringView format, QCalendar cal = QCalendar())
     { return fromString(string.toString(), format, cal); }
     static QDate fromString(const QString &string, QStringView format, QCalendar cal = QCalendar());
-# if QT_STRINGVIEW_LEVEL < 2
     static QDate fromString(const QString &string, Qt::DateFormat format = Qt::TextDate)
     { return fromString(qToStringViewIgnoringNull(string), format); }
     static QDate fromString(const QString &string, const QString &format,
                             QCalendar cal = QCalendar())
     { return fromString(string, qToStringViewIgnoringNull(format), cal); }
-# endif
 #endif
     static bool isValid(int y, int m, int d);
     static bool isLeapYear(int year);
@@ -204,10 +200,8 @@ public:
     int msec() const;
 #if QT_CONFIG(datestring)
     QString toString(Qt::DateFormat f = Qt::TextDate) const;
-#if QT_STRINGVIEW_LEVEL < 2
     QString toString(const QString &format) const
     { return toString(qToStringViewIgnoringNull(format)); }
-#endif
     QString toString(QStringView format) const;
 #endif
     bool setHMS(int h, int m, int s, int ms = 0);
@@ -226,12 +220,10 @@ public:
     static QTime fromString(QStringView string, QStringView format)
     { return fromString(string.toString(), format); }
     static QTime fromString(const QString &string, QStringView format);
-# if QT_STRINGVIEW_LEVEL < 2
     static QTime fromString(const QString &string, Qt::DateFormat format = Qt::TextDate)
     { return fromString(qToStringViewIgnoringNull(string), format); }
     static QTime fromString(const QString &string, const QString &format)
     { return fromString(string, qToStringViewIgnoringNull(format)); }
-# endif
 #endif
     static bool isValid(int h, int m, int s, int ms = 0);
 
@@ -348,10 +340,8 @@ public:
 
 #if QT_CONFIG(datestring)
     QString toString(Qt::DateFormat format = Qt::TextDate) const;
-# if QT_STRINGVIEW_LEVEL < 2
     QString toString(const QString &format, QCalendar cal = QCalendar()) const
     { return toString(qToStringViewIgnoringNull(format), cal); }
-# endif
     QString toString(QStringView format, QCalendar cal = QCalendar()) const;
 #endif
     [[nodiscard]] QDateTime addDays(qint64 days) const;
@@ -385,13 +375,11 @@ public:
     { return fromString(string.toString(), format, cal); }
     static QDateTime fromString(const QString &string, QStringView format,
                                 QCalendar cal = QCalendar());
-# if QT_STRINGVIEW_LEVEL < 2
     static QDateTime fromString(const QString &string, Qt::DateFormat format = Qt::TextDate)
     { return fromString(qToStringViewIgnoringNull(string), format); }
     static QDateTime fromString(const QString &string, const QString &format,
                                 QCalendar cal = QCalendar())
     { return fromString(string, qToStringViewIgnoringNull(format), cal); }
-# endif
 #endif
 
     static QDateTime fromMSecsSinceEpoch(qint64 msecs, Qt::TimeSpec spec = Qt::LocalTime,
diff --git a/src/corelib/tools/qhashfunctions.h b/src/corelib/tools/qhashfunctions.h
index e9da071803..c946cc61bc 100644
--- a/src/corelib/tools/qhashfunctions.h
+++ b/src/corelib/tools/qhashfunctions.h
@@ -156,10 +156,8 @@ inline Q_DECL_PURE_FUNCTION size_t qHash(const QByteArray &key, size_t seed = 0
 #endif
 
 Q_CORE_EXPORT Q_DECL_PURE_FUNCTION size_t qHash(QStringView key, size_t seed = 0) noexcept;
-#if QT_STRINGVIEW_LEVEL < 2
 inline Q_DECL_PURE_FUNCTION size_t qHash(const QString &key, size_t seed = 0) noexcept
 { return qHash(QStringView{key}, seed); }
-#endif
 Q_CORE_EXPORT Q_DECL_PURE_FUNCTION size_t qHash(const QBitArray &key, size_t seed = 0) noexcept;
 Q_CORE_EXPORT Q_DECL_PURE_FUNCTION size_t qHash(QLatin1StringView key, size_t seed = 0) noexcept;
 Q_DECL_CONST_FUNCTION constexpr inline size_t qHash(QKeyCombination key, size_t seed = 0) noexcept