diff -r 000000000000 -r 1918ee327afb tests/auto/qthreadonce/tst_qthreadonce.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/auto/qthreadonce/tst_qthreadonce.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,234 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+
+#include <QtTest/QtTest>
+
+#include <qcoreapplication.h>
+#include <qmutex.h>
+#include <qthread.h>
+#include <qwaitcondition.h>
+#include "qthreadonce.h"
+
+//TESTED_CLASS=
+//TESTED_FILES=corelib/thread/qthreadonce.h corelib/thread/qthreadonce.cpp
+
+class tst_QThreadOnce : public QObject
+{
+    Q_OBJECT
+
+private slots:
+    void sameThread();
+    void sameThread_data();
+    void multipleThreads();
+
+    void nesting();
+    void reentering();
+    void exception();
+};
+
+class SingletonObject: public QObject
+{
+    Q_OBJECT
+public:
+    static int runCount;
+    SingletonObject() { val = 42; ++runCount; }
+    ~SingletonObject() { }
+
+    QBasicAtomicInt val;
+};
+
+class IncrementThread: public QThread
+{
+public:
+    static QBasicAtomicInt runCount;
+    static QSingleton<SingletonObject> singleton;
+    QSemaphore &sem1, &sem2;
+    int &var;
+
+    IncrementThread(QSemaphore *psem1, QSemaphore *psem2, int *pvar, QObject *parent)
+        : QThread(parent), sem1(*psem1), sem2(*psem2), var(*pvar)
+        { start(); }
+
+    ~IncrementThread() { wait(); }
+
+protected:
+    void run()
+        {
+            sem2.release();
+            sem1.acquire();             // synchronize
+
+            Q_ONCE {
+                ++var;
+            }
+            runCount.ref();
+            singleton->val.ref();
+        }
+};
+int SingletonObject::runCount = 0;
+QBasicAtomicInt IncrementThread::runCount = Q_BASIC_ATOMIC_INITIALIZER(0);
+QSingleton<SingletonObject> IncrementThread::singleton;
+
+void tst_QThreadOnce::sameThread_data()
+{
+    SingletonObject::runCount = 0;
+    QTest::addColumn<int>("expectedValue");
+
+    QTest::newRow("first") << 42;
+    QTest::newRow("second") << 43;
+}
+
+void tst_QThreadOnce::sameThread()
+{
+    static int controlVariable = 0;
+    Q_ONCE {
+        QCOMPARE(controlVariable, 0);
+        ++controlVariable;
+    }
+    QCOMPARE(controlVariable, 1);
+
+    static QSingleton<SingletonObject> s;
+    QTEST((int)s->val, "expectedValue");
+    s->val.ref();
+
+    QCOMPARE(SingletonObject::runCount, 1);
+}
+
+void tst_QThreadOnce::multipleThreads()
+{
+#if defined(Q_OS_WINCE) || defined(Q_OS_VXWORKS) || defined(Q_OS_SYMBIAN)
+    const int NumberOfThreads = 20;
+#else
+    const int NumberOfThreads = 100;
+#endif
+    int controlVariable = 0;
+    QSemaphore sem1, sem2(NumberOfThreads);
+
+    QObject *parent = new QObject;
+    for (int i = 0; i < NumberOfThreads; ++i)
+        new IncrementThread(&sem1, &sem2, &controlVariable, parent);
+
+    QCOMPARE(controlVariable, 0); // nothing must have set them yet
+    SingletonObject::runCount = 0;
+    IncrementThread::runCount = 0;
+
+    // wait for all of them to be ready
+    sem2.acquire(NumberOfThreads);
+    // unleash the threads
+    sem1.release(NumberOfThreads);
+
+    // wait for all of them to terminate:
+    delete parent;
+
+    QCOMPARE(controlVariable, 1);
+    QCOMPARE((int)IncrementThread::runCount, NumberOfThreads);
+    QCOMPARE(SingletonObject::runCount, 1);
+}
+
+void tst_QThreadOnce::nesting()
+{
+    int variable = 0;
+    Q_ONCE {
+        Q_ONCE {
+            ++variable;
+        }
+    }
+
+    QVERIFY(variable == 1);
+}
+
+static void reentrant(int control, int &counter)
+{
+    Q_ONCE {
+        if (counter)
+            reentrant(--control, counter);
+        ++counter;
+    }
+    static QSingleton<SingletonObject> s;
+    s->val.ref();
+}
+
+void tst_QThreadOnce::reentering()
+{
+    const int WantedRecursions = 5;
+    int count = 0;
+    SingletonObject::runCount = 0;
+    reentrant(WantedRecursions, count);
+
+    // reentrancy is undefined behavior:
+    QVERIFY(count == 1 || count == WantedRecursions);
+    QCOMPARE(SingletonObject::runCount, 1);
+}
+
+#if !defined(QT_NO_EXCEPTIONS)
+static void exception_helper(int &val)
+{
+    Q_ONCE {
+        if (val++ == 0) throw 0;
+    }
+}
+#endif
+
+void tst_QThreadOnce::exception()
+{
+#if defined(QT_NO_EXCEPTIONS)
+    QSKIP("Compiled without exceptions, skipping test", SkipAll);
+#else
+    int count = 0;
+
+    try {
+        exception_helper(count);
+    } catch (...) {
+        // nothing
+    }
+    QCOMPARE(count, 1);
+
+    try {
+        exception_helper(count);
+    } catch (...) {
+        QVERIFY2(false, "Exception shouldn't have been thrown...");
+    }
+    QCOMPARE(count, 2);
+#endif
+}
+
+QTEST_MAIN(tst_QThreadOnce)
+#include "tst_qthreadonce.moc"