QVarLengthArray - check if iterators arguments are valid (in debugmode)

This add checks on iterators on insert and erase.

Change-Id: I41d96e038d74668cc1df10b6d42cde4b82f8a696
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qvarlengtharray.h

@@ -192,6 +192,11 @@ private:
         qint64 q_for_alignment_1;
         double q_for_alignment_2;
     };
+
+    bool isValidIterator(const const_iterator &i) const
+    {
+        return (i <= constEnd()) && (constBegin() <= i);
+    }
 };
 
 template <class T, int Prealloc>
@@ -355,6 +360,8 @@ inline void QVarLengthArray<T, Prealloc>::replace(int i, const T &t)
 template <class T, int Prealloc>
 Q_OUTOFLINE_TEMPLATE typename QVarLengthArray<T, Prealloc>::iterator QVarLengthArray<T, Prealloc>::insert(const_iterator before, size_type n, const T &t)
 {
+    Q_ASSERT_X(isValidIterator(before), "QVarLengthArray::insert", "The specified const_iterator argument 'before' is invalid");
+
     int offset = int(before - ptr);
     if (n != 0) {
         resize(s + n);
@@ -382,6 +389,9 @@ Q_OUTOFLINE_TEMPLATE typename QVarLengthArray<T, Prealloc>::iterator QVarLengthA
 template <class T, int Prealloc>
 Q_OUTOFLINE_TEMPLATE typename QVarLengthArray<T, Prealloc>::iterator QVarLengthArray<T, Prealloc>::erase(const_iterator abegin, const_iterator aend)
 {
+    Q_ASSERT_X(isValidIterator(abegin), "QVarLengthArray::insert", "The specified const_iterator argument 'abegin' is invalid");
+    Q_ASSERT_X(isValidIterator(aend), "QVarLengthArray::insert", "The specified const_iterator argument 'aend' is invalid");
+
     int f = int(abegin - ptr);
     int l = int(aend - ptr);
     int n = l - f;

tests/manual/corelib/tools/qvarlengtharray/main.cpp

@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Thorbjørn Lund Martsum - tmartsum[at]gmail.com
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the test suite 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QDebug>
+//#define QT_STRICT_ITERATORS
+#include <QVarLengthArray>
+
+void testErase()
+{
+    QVarLengthArray<int> a, b;
+    a.append(5);
+    a.append(6);
+    a.append(7);
+    b = a;
+    a.erase(a.begin());
+    a.erase(a.end() - 1);
+    qDebug() << "erase - no errors until now";
+    // a.erase(a.end());
+    a.erase(b.begin());
+}
+
+void testInsert()
+{
+    QVarLengthArray<int> a, b;
+    a.insert(a.begin(), 1);
+    a.insert(a.begin(), 2);
+    a.insert(a.end(), 3);
+    b = a;
+    qDebug() << "insert - no errors until now";
+    a.insert(b.begin(), 1, 4);
+}
+
+int main()
+{
+    // testErase();
+    testInsert();
+    return 0;
+}

tests/manual/corelib/tools/qvarlengtharray/main.pro

@@ -0,0 +1 @@
+SOURCES=main.cpp