1 files changed, 137 insertions, 0 deletions
diff --git a/src/corelib/text/qstringbuilder.cpp b/src/corelib/text/qstringbuilder.cpp
new file mode 100644
index 0000000000..cf443ec369
--- /dev/null
+++ b/src/corelib/text/qstringbuilder.cpp
@@ -0,0 +1,137 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qstringbuilder.h"
+#include <private/qutfcodec_p.h>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \class QStringBuilder
+    \inmodule QtCore
+    \internal
+    \reentrant
+    \since 4.6
+
+    \brief The QStringBuilder class is a template class that provides a facility to build up QStrings and QByteArrays from smaller chunks.
+
+    \ingroup tools
+    \ingroup shared
+    \ingroup string-processing
+
+
+    To build a QString by multiple concatenations, QString::operator+()
+    is typically used. This causes \e{n - 1} allocations when building
+    a string from \e{n} chunks. The same is true for QByteArray.
+
+    QStringBuilder uses expression templates to collect the individual
+    chunks, compute the total size, allocate the required amount of
+    memory for the final string object, and copy the chunks into the
+    allocated memory.
+
+    The QStringBuilder class is not to be used explicitly in user
+    code.  Instances of the class are created as return values of the
+    operator%() function, acting on objects of the following types:
+
+    For building QStrings:
+
+    \list
+    \li QString, QStringRef, (since 5.10:) QStringView
+    \li QChar, QCharRef, QLatin1Char, (since 5.10:) \c char16_t,
+    \li QLatin1String,
+    \li (since 5.10:) \c{const char16_t[]} (\c{u"foo"}),
+    \li QByteArray, \c char, \c{const char[]}.
+    \endlist
+
+    The types in the last list point are only available when
+    \c QT_NO_CAST_FROM_ASCII is not defined.
+
+    For building QByteArrays:
+
+    \list
+    \li QByteArray, \c char, \c{const char[]}.
+    \endlist
+
+    Concatenating strings with operator%() generally yields better
+    performance than using \c QString::operator+() on the same chunks
+    if there are three or more of them, and performs equally well in other
+    cases.
+
+    \sa QLatin1String, QString
+*/
+
+/*! \fn template <typename A, typename B> QStringBuilder<A, B>::QStringBuilder(const A &a, const B &b)
+  Constructs a QStringBuilder from \a a and \a b.
+ */
+
+/* \fn template <typename A, typename B> QStringBuilder<A, B>::operator%(const A &a, const B &b)
+
+    Returns a \c QStringBuilder object that is converted to a QString object
+    when assigned to a variable of QString type or passed to a function that
+    takes a QString parameter.
+
+    This function is usable with arguments of type \c QString,
+    \c QLatin1String, \c QStringRef,
+    \c QChar, \c QCharRef, \c QLatin1Char, and \c char.
+*/
+
+/* \fn template <typename A, typename B> QByteArray QStringBuilder<A, B>::toLatin1() const
+  Returns a Latin-1 representation of the string as a QByteArray.  The
+  returned byte array is undefined if the string contains non-Latin1
+  characters.
+ */
+/* \fn template <typename A, typename B> QByteArray QStringBuilder<A, B>::toUtf8() const
+  Returns a UTF-8 representation of the string as a QByteArray.
+ */
+
+
+/*!
+    \internal
+ */
+void QAbstractConcatenable::convertFromAscii(const char *a, int len, QChar *&out) noexcept
+{
+    if (Q_UNLIKELY(len == -1)) {
+        if (!a)
+            return;
+        len = int(strlen(a));
+    }
+    out = QUtf8::convertToUnicode(out, a, len);
+}
+
+QT_END_NAMESPACE