statemachine: Purge restorable properties when they are restored

Previously, a registered restorable property would only be
unregistered if the property was animated (see
QStateMachinePrivate::_q_animationFinished()).
But if a property is set directly, it should also be unregistered;
otherwise, the state machine would use the previously saved (stale)
value the next time that property should be restored.

Change-Id: I5d246aa5355ddd0ba5f81b0186a9f0e4f3bbaa3f
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com>

src/corelib/statemachine/qstatemachine.cpp

@@ -841,6 +841,8 @@ void QStateMachinePrivate::applyProperties(const QList<QAbstractTransition*> &tr
             for (int i = 0; i < assignments.size(); ++i) {
                 const QPropertyAssignment &assn = assignments.at(i);
                 assn.write();
+                if (!assn.explicitlySet)
+                    unregisterRestorable(assn.object, assn.propertyName);
             }
         }
     }

tests/auto/corelib/statemachine/qstatemachine/tst_qstatemachine.cpp

@@ -190,6 +190,7 @@ private slots:
     void deletePropertyAssignmentObjectBeforeEntry();
     void deletePropertyAssignmentObjectBeforeRestore();
     void deleteInitialState();
+    void setPropertyAfterRestore();
 };
 
 class TestState : public QState
@@ -4086,5 +4087,50 @@ void tst_QStateMachine::deleteInitialState()
     QCoreApplication::processEvents();
 }
 
+void tst_QStateMachine::setPropertyAfterRestore()
+{
+    QStateMachine machine;
+    machine.setGlobalRestorePolicy(QStateMachine::RestoreProperties);
+
+    QObject *object = new QObject(&machine);
+    object->setProperty("a", 1);
+
+    QState *s1 = new QState(&machine);
+    machine.setInitialState(s1);
+    s1->assignProperty(object, "a", 2);
+
+    QState *s2 = new QState(&machine);
+    s1->addTransition(new EventTransition(QEvent::User, s2));
+
+    QState *s3 = new QState(&machine);
+    s3->assignProperty(object, "a", 4);
+    s2->addTransition(new EventTransition(QEvent::User, s3));
+
+    QState *s4 = new QState(&machine);
+    s3->addTransition(new EventTransition(QEvent::User, s4));
+
+    machine.start();
+    QTRY_VERIFY(machine.configuration().contains(s1));
+    QCOMPARE(object->property("a").toInt(), 2);
+
+    machine.postEvent(new QEvent(QEvent::User));
+    QTRY_VERIFY(machine.configuration().contains(s2));
+    QCOMPARE(object->property("a").toInt(), 1); // restored
+
+    // Set property outside of state machine; this is the value
+    // that should be remembered in the next transition
+    object->setProperty("a", 3);
+
+    machine.postEvent(new QEvent(QEvent::User));
+    QTRY_VERIFY(machine.configuration().contains(s3));
+    QCOMPARE(object->property("a").toInt(), 4);
+
+    machine.postEvent(new QEvent(QEvent::User));
+    QTRY_VERIFY(machine.configuration().contains(s4));
+    QCOMPARE(object->property("a").toInt(), 3); // restored
+
+    delete object;
+}
+
 QTEST_MAIN(tst_QStateMachine)
 #include "tst_qstatemachine.moc"