Always rebuild the class info for wrapped objects

When a new transport is accessing a previously wrapped object, we used
to send potentially outdated property values.

[ChangeLog][QWebChannel][General] Send current property values when
another transport is accessing a previously wrapped object.

Fixes: QTBUG-62388
Change-Id: I5cd5772b42c3cb9860e945bb85f77f0e3b6d6ea0
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@qt.io>

3 files changed, 30 insertions, 16 deletions

diff --git a/src/webchannel/qmetaobjectpublisher.cpp b/src/webchannel/qmetaobjectpublisher.cpp
index 3c1d030..b0581c4 100644
--- a/src/webchannel/qmetaobjectpublisher.cpp
+++ b/src/webchannel/qmetaobjectpublisher.cpp
@@ -492,7 +492,7 @@ QObject *QMetaObjectPublisher::unwrapObject(const QString &objectId) const
 {
     if (!objectId.isEmpty()) {
         ObjectInfo objectInfo = wrappedObjects.value(objectId);
-        if (objectInfo.object && !objectInfo.classinfo.isEmpty())
+        if (objectInfo.object)
             return objectInfo.object;
         QObject *object = registeredObjects.value(objectId);
         if (object)
@@ -577,7 +577,7 @@ QJsonValue QMetaObjectPublisher::wrapResult(const QVariant &result, QWebChannelA
 
             classInfo = classInfoForObject(object, transport);
 
-            ObjectInfo oi(object, classInfo);
+            ObjectInfo oi(object);
             if (transport) {
                 oi.transports.append(transport);
             } else {
@@ -598,7 +598,7 @@ QJsonValue QMetaObjectPublisher::wrapResult(const QVariant &result, QWebChannelA
                 wrappedObjects[id].transports.append(transport);
                 transportedWrappedObjects.insert(transport, id);
             }
-            classInfo = wrappedObjects.value(id).classinfo;
+            classInfo = classInfoForObject(object, transport);
         }
 
         QJsonObject objectInfo;
diff --git a/src/webchannel/qmetaobjectpublisher_p.h b/src/webchannel/qmetaobjectpublisher_p.h
index 1535a70..23a9b96 100644
--- a/src/webchannel/qmetaobjectpublisher_p.h
+++ b/src/webchannel/qmetaobjectpublisher_p.h
@@ -256,15 +256,10 @@ private:
     // Groups individually wrapped objects with their class information and the transports that have access to it.
     struct ObjectInfo
     {
-        ObjectInfo()
-            : object(Q_NULLPTR)
-        {}
-        ObjectInfo(QObject *o, const QJsonObject &i)
+        ObjectInfo(QObject *o = nullptr)
             : object(o)
-            , classinfo(i)
         {}
         QObject *object;
-        QJsonObject classinfo;
         QVector<QWebChannelAbstractTransport*> transports;
     };
 
diff --git a/tests/auto/webchannel/tst_webchannel.cpp b/tests/auto/webchannel/tst_webchannel.cpp
index 790e5ac..24778c7 100644
--- a/tests/auto/webchannel/tst_webchannel.cpp
+++ b/tests/auto/webchannel/tst_webchannel.cpp
@@ -1127,13 +1127,22 @@ void TestWebChannel::qtbug62388_wrapObjectMultipleTransports()
     auto queryObjectInfo = [&channel](QObject *obj, QWebChannelAbstractTransport *transport) {
         return channel.d_func()->publisher->wrapResult(QVariant::fromValue(obj), transport).toObject();
     };
-    const auto objectInfo = queryObjectInfo(&obj, m_dummyTransport);
 
-    QCOMPARE(objectInfo.length(), 3);
-    QVERIFY(objectInfo.contains("id"));
-    QVERIFY(objectInfo.contains("__QObject*__"));
-    QVERIFY(objectInfo.contains("data"));
-    QVERIFY(objectInfo.value("__QObject*__").isBool() && objectInfo.value("__QObject*__").toBool());
+    auto verifyObjectInfo = [&obj](const QJsonObject &objectInfo) {
+
+        QCOMPARE(objectInfo.length(), 3);
+        QVERIFY(objectInfo.contains("id"));
+        QVERIFY(objectInfo.contains("__QObject*__"));
+        QVERIFY(objectInfo.contains("data"));
+        QVERIFY(objectInfo.value("__QObject*__").isBool() && objectInfo.value("__QObject*__").toBool());
+
+        const auto propIndex = obj.metaObject()->indexOfProperty("prop");
+        const auto prop = objectInfo["data"].toObject()["properties"].toArray()[propIndex].toArray()[3].toString();
+        QCOMPARE(prop, obj.prop());
+    };
+
+    const auto objectInfo = queryObjectInfo(&obj, m_dummyTransport);
+    verifyObjectInfo(objectInfo);
 
     const auto id = objectInfo.value("id").toString();
 
@@ -1143,7 +1152,17 @@ void TestWebChannel::qtbug62388_wrapObjectMultipleTransports()
     initTransport(&transport);
     QCOMPARE(queryObjectInfo(&obj, &transport), objectInfo);
 
-    // don't crash when the transport is destroyed
+    obj.setProp("asdf");
+
+    const auto objectInfo2 = queryObjectInfo(&obj, m_dummyTransport);
+    QVERIFY(objectInfo2 != objectInfo);
+    verifyObjectInfo(objectInfo2);
+
+    DummyTransport transport2;
+    initTransport(&transport2);
+    QCOMPARE(queryObjectInfo(&obj, &transport2), objectInfo2);
+
+    // don't crash when the transports are destroyed
 }
 
 QTEST_MAIN(TestWebChannel)