QLocale: add QStringView overload of number parsing functions

This ports all to<Integer>() functions in QLocale to QStringView.

Change-Id: Idc3f026d5afdf51abab670b54ea96d2361cdc350
Reviewed-by: Anton Kudryavtsev <antkudr@mail.ru>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/corelib/doc/snippets/code/src_corelib_tools_qlocale.cpp

@@ -103,3 +103,20 @@ d = german.toDouble( "1234.56", &ok );  // ok == false
 
 d = german.toDouble( "1.234", &ok );    // ok == true, d == 1234.0
 //! [3]
+
+//! [3-qstringview]
+bool ok;
+double d;
+
+QLocale c(QLocale::C);
+d = c.toDouble(u"1234.56", &ok);  // ok == true, d == 1234.56
+d = c.toDouble(u"1,234.56", &ok); // ok == true, d == 1234.56
+d = c.toDouble(u"1234,56", &ok);  // ok == false
+
+QLocale german(QLocale::German);
+d = german.toDouble(u"1234,56", &ok);  // ok == true, d == 1234.56
+d = german.toDouble(u"1.234,56", &ok); // ok == true, d == 1234.56
+d = german.toDouble(u"1234.56", &ok);  // ok == false
+
+d = german.toDouble(u"1.234", &ok);    // ok == true, d == 1234.0
+//! [3-qstringview]

src/corelib/tools/qlocale.cpp

@@ -1202,6 +1202,7 @@ QString QLocale::scriptToString(QLocale::Script script)
     return QLatin1String(script_name_list + script_name_index[script]);
 }
 
+#if QT_STRINGVIEW_LEVEL < 2
 /*!
     Returns the short int represented by the localized string \a s.
 
@@ -1523,7 +1524,176 @@ double QLocale::toDouble(const QStringRef &s, bool *ok) const
 {
     return d->m_data->stringToDouble(s, ok, d->m_numberOptions);
 }
+#endif // QT_STRINGVIEW_LEVEL < 2
 
+/*!
+    Returns the short int represented by the localized string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toUShort(), toString()
+
+    \since 5.10
+*/
+
+short QLocale::toShort(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<short>(d, s, ok);
+}
+
+/*!
+    Returns the unsigned short int represented by the localized string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toShort(), toString()
+
+    \since 5.10
+*/
+
+ushort QLocale::toUShort(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<ushort>(d, s, ok);
+}
+
+/*!
+    Returns the int represented by the localized string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toUInt(), toString()
+
+    \since 5.10
+*/
+
+int QLocale::toInt(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<int>(d, s, ok);
+}
+
+/*!
+    Returns the unsigned int represented by the localized string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toInt(), toString()
+
+    \since 5.10
+*/
+
+uint QLocale::toUInt(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<uint>(d, s, ok);
+}
+
+/*!
+    Returns the long long int represented by the localized string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toInt(), toULongLong(), toDouble(), toString()
+
+    \since 5.10
+*/
+
+
+qlonglong QLocale::toLongLong(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<qlonglong>(d, s, ok);
+}
+
+/*!
+    Returns the unsigned long long int represented by the localized
+    string \a s.
+
+    If the conversion fails, the function returns 0.
+
+    If \a ok is not null, failure is reported by setting *ok to false, and
+    success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toLongLong(), toInt(), toDouble(), toString()
+
+    \since 5.10
+*/
+
+qulonglong QLocale::toULongLong(QStringView s, bool *ok) const
+{
+    return toIntegral_helper<qulonglong>(d, s, ok);
+}
+
+/*!
+    Returns the float represented by the localized string \a s, or 0.0
+    if the conversion failed.
+
+    If \a ok is not null, reports failure by setting
+    *ok to false and success by setting *ok to true.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toDouble(), toInt(), toString()
+
+    \since 5.10
+*/
+
+float QLocale::toFloat(QStringView s, bool *ok) const
+{
+    return QLocaleData::convertDoubleToFloat(toDouble(s, ok), ok);
+}
+
+/*!
+    Returns the double represented by the localized string \a s, or
+    0.0 if the conversion failed.
+
+    If \a ok is not null, reports failure by setting
+    *ok to false and success by setting *ok to true.
+
+    Unlike QString::toDouble(), this function does not fall back to
+    the "C" locale if the string cannot be interpreted in this
+    locale.
+
+    \snippet code/src_corelib_tools_qlocale.cpp 3-qstringview
+
+    Notice that the last conversion returns 1234.0, because '.' is the
+    thousands group separator in the German locale.
+
+    This function ignores leading and trailing whitespace.
+
+    \sa toFloat(), toInt(), toString()
+
+    \since 5.10
+*/
+
+double QLocale::toDouble(QStringView s, bool *ok) const
+{
+    return d->m_data->stringToDouble(s, ok, d->m_numberOptions);
+}
 
 /*!
     Returns a localized string representation of \a i.

src/corelib/tools/qlocale.h

@@ -935,6 +935,7 @@ public:
     QString nativeLanguageName() const;
     QString nativeCountryName() const;
 
+#if QT_STRINGVIEW_LEVEL < 2
     short toShort(const QString &s, bool *ok = Q_NULLPTR) const;
     ushort toUShort(const QString &s, bool *ok = Q_NULLPTR) const;
     int toInt(const QString &s, bool *ok = Q_NULLPTR) const;
@@ -952,6 +953,16 @@ public:
     qulonglong toULongLong(const QStringRef &s, bool *ok = Q_NULLPTR) const;
     float toFloat(const QStringRef &s, bool *ok = Q_NULLPTR) const;
     double toDouble(const QStringRef &s, bool *ok = Q_NULLPTR) const;
+#endif
+
+    short toShort(QStringView s, bool *ok = nullptr) const;
+    ushort toUShort(QStringView s, bool *ok = nullptr) const;
+    int toInt(QStringView s, bool *ok = nullptr) const;
+    uint toUInt(QStringView s, bool *ok = nullptr) const;
+    qlonglong toLongLong(QStringView s, bool *ok = nullptr) const;
+    qulonglong toULongLong(QStringView s, bool *ok = nullptr) const;
+    float toFloat(QStringView s, bool *ok = nullptr) const;
+    double toDouble(QStringView s, bool *ok = nullptr) const;
 
     QString toString(qlonglong i) const;
     QString toString(qulonglong i) const;