Move-enable QSignalBlocker

When QSignalBlocker was reviewed, move semantics were asked for.
This patch add them.

This makes QSignalBlocker usable as a by-value argument (to transfer
control of signal blocking into a function) as well as as a return
value (to transfer control of signal blocking out of a function).

Change-Id: I714aa2a283bb33dba76e860649e88ed202e913c5
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

1 files changed, 100 insertions, 0 deletions

diff --git a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
index c6fb1025ac..4776bdbbc9 100644
--- a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
+++ b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
@@ -103,6 +103,7 @@ private slots:
     void recursiveSignalEmission();
 #endif
     void signalBlocking();
+    void signalBlockingMoveAssignment();
     void blockingQueuedConnection();
     void childEvents();
     void installEventFilter();
@@ -3030,6 +3031,105 @@ void tst_QObject::signalBlocking()
     receiver.reset();
 }
 
+void tst_QObject::signalBlockingMoveAssignment()
+{
+#ifdef Q_COMPILER_RVALUE_REFS
+    QObject o1, o2;
+
+    // move-assignment: both block other objects
+    {
+        QSignalBlocker b(&o1);
+        QVERIFY(o1.signalsBlocked());
+
+        QVERIFY(!o2.signalsBlocked());
+        b = QSignalBlocker(&o2);
+        QVERIFY(!o1.signalsBlocked());
+        QVERIFY(o2.signalsBlocked());
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+    // move-assignment: from inert other
+    {
+        QSignalBlocker b(&o1);
+        QVERIFY(o1.signalsBlocked());
+        b = QSignalBlocker(0);
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+    // move-assignment: to inert *this
+    {
+        QSignalBlocker b(0);
+        QVERIFY(!o1.signalsBlocked());
+        {
+            QSignalBlocker inner(&o1);
+            QVERIFY(o1.signalsBlocked());
+            b = std::move(inner);
+        }
+        QVERIFY(o1.signalsBlocked());
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+    // move-assignment: both block the same object, neither is unblocked
+    {
+        QSignalBlocker b(&o1);
+        QVERIFY(o1.signalsBlocked());
+        {
+            b.unblock(); // make sure inner.m_blocked = false
+            QVERIFY(!o1.signalsBlocked());
+            QSignalBlocker inner(&o1);
+            QVERIFY(o1.signalsBlocked());
+            b.reblock();
+            QVERIFY(o1.signalsBlocked());
+            b = std::move(inner);
+        }
+        QVERIFY(o1.signalsBlocked());
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+    // move-assignment: both block the same object, but *this is unblocked
+    {
+        QSignalBlocker b(&o1);
+        QVERIFY(o1.signalsBlocked());
+        b.unblock();
+        QVERIFY(!o1.signalsBlocked());
+        b = QSignalBlocker(&o1);
+        QVERIFY(o1.signalsBlocked());
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+    // move-assignment: both block the same object, but other is unblocked
+    {
+        QSignalBlocker b(&o1);
+        {
+            QVERIFY(o1.signalsBlocked());
+            QSignalBlocker inner(&o1);
+            QVERIFY(o1.signalsBlocked());
+            inner.unblock();
+            QVERIFY(o1.signalsBlocked());
+            b = std::move(inner);
+            QVERIFY(!o1.signalsBlocked());
+        }
+        QVERIFY(!o1.signalsBlocked());
+    }
+
+    QVERIFY(!o1.signalsBlocked());
+    QVERIFY(!o2.signalsBlocked());
+
+#else
+    QSKIP("This compiler is not in C++11 mode or doesn't support move semantics");
+#endif // Q_COMPILER_RVALUE_REFS
+}
+
 void tst_QObject::blockingQueuedConnection()
 {
     {