Add QStringView::split()

The implementation has to live in qstringlist.h and
qregularexpression.h, as those classes are only forward
declared in qstring.h.

Task-number: QTBUG-86516
Change-Id: Ia9b3ff48999d1c2e7df905191ee192764b309d08
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

4 files changed, 70 insertions, 0 deletions

diff --git a/src/corelib/text/qregularexpression.h b/src/corelib/text/qregularexpression.h
index 4fa258b080..e00979527d 100644
--- a/src/corelib/text/qregularexpression.h
+++ b/src/corelib/text/qregularexpression.h
@@ -278,6 +278,20 @@ private:
 
 Q_DECLARE_SHARED(QRegularExpressionMatchIterator)
 
+// implementation here, so we have all required classes
+inline
+QList<QStringView> QStringView::split(const QRegularExpression &sep, Qt::SplitBehavior behavior) const
+{
+    Q_ASSERT(int(m_size) == m_size);
+    QString s = QString::fromRawData(data(), int(m_size));
+    const auto split = s.splitRef(sep, behavior);
+    QList<QStringView> result;
+    result.reserve(split.size());
+    for (const QStringRef &r : split)
+        result.append(r);
+    return result;
+}
+
 QT_END_NAMESPACE
 
 #endif // QREGULAREXPRESSION_H
diff --git a/src/corelib/text/qstringlist.h b/src/corelib/text/qstringlist.h
index 9ea379bb92..02b129a3cb 100644
--- a/src/corelib/text/qstringlist.h
+++ b/src/corelib/text/qstringlist.h
@@ -384,6 +384,31 @@ inline int QStringList::lastIndexOf(const QRegularExpression &rx, int from) cons
 #endif // QT_CONFIG(regularexpression)
 #endif // Q_QDOC
 
+// those methods need to be here, so they can be implemented inline
+inline
+QList<QStringView> QStringView::split(QStringView sep, Qt::SplitBehavior behavior, Qt::CaseSensitivity cs) const
+{
+    Q_ASSERT(int(m_size) == m_size);
+    QString s = QString::fromRawData(data(), int(m_size));
+    const auto split = s.splitRef(sep.toString(), behavior, cs);
+    QList<QStringView> result;
+    for (const QStringRef &r : split)
+        result.append(QStringView(m_data + r.position(), r.size()));
+    return result;
+}
+
+inline
+QList<QStringView> QStringView::split(QChar sep, Qt::SplitBehavior behavior, Qt::CaseSensitivity cs) const
+{
+    Q_ASSERT(int(m_size) == m_size);
+    QString s = QString::fromRawData(data(), int(m_size));
+    const auto split = s.splitRef(sep, behavior, cs);
+    QList<QStringView> result;
+    for (const QStringRef &r : split)
+        result.append(QStringView(m_data + r.position(), r.size()));
+    return result;
+}
+
 QT_END_NAMESPACE
 
 #endif // QSTRINGLIST_H
diff --git a/src/corelib/text/qstringview.cpp b/src/corelib/text/qstringview.cpp
index 1451dfed44..f3712a412a 100644
--- a/src/corelib/text/qstringview.cpp
+++ b/src/corelib/text/qstringview.cpp
@@ -899,6 +899,23 @@ QT_BEGIN_NAMESPACE
 */
 
 /*!
+    \fn QList<QStringView> QStringView::split(QStringView sep, Qt::SplitBehavior behavior, Qt::CaseSensitivity cs) const;
+    \fn QList<QStringView> QStringView::split(QChar sep, Qt::SplitBehavior behavior, Qt::CaseSensitivity cs) const;
+    \fn QList<QStringView> QStringView::split(const QRegularExpression &sep, Qt::SplitBehavior behavior) const;
+
+    Splits the string into substrings wherever \a sep occurs, and
+    returns the list of those strings.
+
+    See QString::split() for how \a sep, \a behavior and \a cs interact to form
+    the result.
+
+    \note This method has been added in 5.15.2 to simplify writing code that is portable
+    between Qt 5.15 and Qt 6. The implementation is not tuned for performance in Qt 5.
+
+    \since 5.15.2
+*/
+
+/*!
     \fn QStringView::toWCharArray(wchar_t *array) const
     \since 5.14
 
diff --git a/src/corelib/text/qstringview.h b/src/corelib/text/qstringview.h
index e599e5a8c2..5e561d88a8 100644
--- a/src/corelib/text/qstringview.h
+++ b/src/corelib/text/qstringview.h
@@ -55,6 +55,7 @@ QT_BEGIN_NAMESPACE
 
 class QString;
 class QStringRef;
+class QRegularExpression;
 
 namespace QtPrivate {
 template <typename Char>
@@ -323,6 +324,19 @@ public:
 
     Q_REQUIRED_RESULT inline int toWCharArray(wchar_t *array) const; // defined in qstring.h
 
+    Q_REQUIRED_RESULT inline
+    QList<QStringView> split(QStringView sep,
+                             Qt::SplitBehavior behavior = Qt::KeepEmptyParts,
+                             Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
+    Q_REQUIRED_RESULT inline
+    QList<QStringView> split(QChar sep, Qt::SplitBehavior behavior = Qt::KeepEmptyParts,
+                             Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
+
+#if QT_CONFIG(regularexpression)
+    Q_REQUIRED_RESULT inline
+    QList<QStringView> split(const QRegularExpression &sep, Qt::SplitBehavior behavior = Qt::KeepEmptyParts) const;
+#endif
+
     //
     // STL compatibility API:
     //