Add QByteArrayView::trimmed()

Unlike simplified(), it just moves the end-points, without needing to
modify contents, so it makes sense (as for QStringView and
QLatin1String) to provide it. Moved QByteArray's trimmed() tests to
tst_QByteArrayApiSymmetry so that QBAV can now share them.

[ChangeLog][QtCore][QByteArrayView] Added trimmed().

Change-Id: Ifd7a752adb5f3d3e2ad0aa8220efa7e7d2d39baa
Reviewed-by: Sona Kurazyan <sona.kurazyan@qt.io>

4 files changed, 30 insertions, 3 deletions

diff --git a/src/corelib/text/qbytearray.cpp b/src/corelib/text/qbytearray.cpp
index d97375897d..23db7db3e2 100644
--- a/src/corelib/text/qbytearray.cpp
+++ b/src/corelib/text/qbytearray.cpp
@@ -3390,6 +3390,13 @@ QByteArray QByteArray::trimmed_helper(QByteArray &a)
     return QStringAlgorithms<QByteArray>::trimmed_helper(a);
 }
 
+QByteArrayView QtPrivate::trimmed(QByteArrayView view) noexcept
+{
+    auto start = view.begin();
+    auto stop = view.end();
+    QStringAlgorithms<QByteArrayView>::trimmed_helper_positions(start, stop);
+    return QByteArrayView(start, stop);
+}
 
 /*!
     Returns a byte array of size \a width that contains this byte array padded
diff --git a/src/corelib/text/qbytearrayalgorithms.h b/src/corelib/text/qbytearrayalgorithms.h
index be1e6cc953..638af2948b 100644
--- a/src/corelib/text/qbytearrayalgorithms.h
+++ b/src/corelib/text/qbytearrayalgorithms.h
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2020 The Qt Company Ltd.
+** Copyright (C) 2021 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -72,6 +72,8 @@ qsizetype count(QByteArrayView haystack, QByteArrayView needle) noexcept;
 
 [[nodiscard]] Q_CORE_EXPORT int compareMemory(QByteArrayView lhs, QByteArrayView rhs);
 
+[[nodiscard]] Q_CORE_EXPORT Q_DECL_PURE_FUNCTION QByteArrayView trimmed(QByteArrayView s) noexcept;
+
 } // namespace QtPrivate
 
 /*****************************************************************************
diff --git a/src/corelib/text/qbytearrayview.h b/src/corelib/text/qbytearrayview.h
index 9d35e21415..1dfc65b4c4 100644
--- a/src/corelib/text/qbytearrayview.h
+++ b/src/corelib/text/qbytearrayview.h
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2020 The Qt Company Ltd.
+** Copyright (C) 2021 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -240,6 +240,9 @@ public:
     constexpr void chop(qsizetype n)
     { Q_ASSERT(n >= 0); Q_ASSERT(n <= size()); m_size -= n; }
 
+    [[nodiscard]] QByteArrayView trimmed() const noexcept
+    { return QtPrivate::trimmed(*this); }
+
     [[nodiscard]] bool startsWith(QByteArrayView other) const noexcept
     { return QtPrivate::startsWith(*this, other); }
     [[nodiscard]] bool startsWith(char c) const noexcept
diff --git a/src/corelib/text/qbytearrayview.qdoc b/src/corelib/text/qbytearrayview.qdoc
index 30d8d47685..740734ebbd 100644
--- a/src/corelib/text/qbytearrayview.qdoc
+++ b/src/corelib/text/qbytearrayview.qdoc
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2020 The Qt Company Ltd.
+** Copyright (C) 2021 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the documentation of the Qt Toolkit.
@@ -620,6 +620,21 @@
 */
 
 /*!
+    \fn QByteArrayView QByteArrayView::trimmed() const noexcept
+    \since 6.3
+
+    Returns a copy of this byte array view with spacing characters
+    removed from the start and end.
+
+    The spacing characters are those for which the standard C++ \c isspace()
+    function returns \c true in the C locale; these are the ASCII characters
+    tabulation '\\t', line feed '\\n', carriage return '\\r', vertical
+    tabulation '\\v', form feed '\\f', and space ' '.
+
+    \sa QChar::SpecialCharacter, {QByteArray#Spacing Characters}{Spacing Characters}
+*/
+
+/*!
     \fn bool QByteArrayView::startsWith(QByteArrayView bv) const
     \fn bool QByteArrayView::startsWith(char ch) const