From d2921ffc52fed380326f8abb86d6d659cc47f9d1 Mon Sep 17 00:00:00 2001
From: Chris Adams <christopher.adams@nokia.com>
Date: Fri, 24 Feb 2012 14:40:11 +1000
Subject: [PATCH] Check engine equality condition inside null ptr check

Previously, we asserted if the engine associated with the two external
resources from the arguments to the object comparison callback were
not equal, prior to checking that the external resources were non-null.

Task-number: QTBUG-24489
Change-Id: I4b2bd2377fcf38163d1341e43e056b1405ab72ac
Reviewed-by: Yunqiao Yin <charles.yin@nokia.com>
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>
---
 src/declarative/qml/v8/qv8engine.cpp                        |  6 ++++--
 .../qdeclarativevaluetypes/data/nonValueTypeComparison.qml  | 10 ++++++++++
 .../qdeclarativevaluetypes/tst_qdeclarativevaluetypes.cpp   | 13 +++++++++++++
 3 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 tests/auto/declarative/qdeclarativevaluetypes/data/nonValueTypeComparison.qml

diff --git a/src/declarative/qml/v8/qv8engine.cpp b/src/declarative/qml/v8/qv8engine.cpp
index 04589fe..70e6528 100644
--- a/src/declarative/qml/v8/qv8engine.cpp
+++ b/src/declarative/qml/v8/qv8engine.cpp
@@ -75,12 +75,14 @@ static bool ObjectComparisonCallback(v8::Local<v8::Object> lhs, v8::Local<v8::Ob
     if (lhs == rhs)
         return true;
 
+    if (lhs.IsEmpty() || rhs.IsEmpty())
+        return false;
+
     QV8ObjectResource *lhsr = static_cast<QV8ObjectResource*>(lhs->GetExternalResource());
     QV8ObjectResource *rhsr = static_cast<QV8ObjectResource*>(rhs->GetExternalResource());
 
-    Q_ASSERT(lhsr->engine == rhsr->engine);
-
     if (lhsr && rhsr) {
+        Q_ASSERT(lhsr->engine == rhsr->engine);
         QV8ObjectResource::ResourceType lhst = lhsr->resourceType();
         QV8ObjectResource::ResourceType rhst = rhsr->resourceType();
 
diff --git a/tests/auto/declarative/qdeclarativevaluetypes/data/nonValueTypeComparison.qml b/tests/auto/declarative/qdeclarativevaluetypes/data/nonValueTypeComparison.qml
new file mode 100644
index 0000000..0ffa5eb
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativevaluetypes/data/nonValueTypeComparison.qml
@@ -0,0 +1,10 @@
+import QtQuick 2.0
+
+Item {
+    property variant somepoint: Qt.point(1,2)
+    property variant randomjsobj: {"some": 1, "thing": 2}
+    property bool test1: somepoint != randomjsobj
+
+    property variant similar: {"x":1, "y":2}
+    property bool test2: somepoint != similar
+}
diff --git a/tests/auto/declarative/qdeclarativevaluetypes/tst_qdeclarativevaluetypes.cpp b/tests/auto/declarative/qdeclarativevaluetypes/tst_qdeclarativevaluetypes.cpp
index 72ec7a5..e701efa 100644
--- a/tests/auto/declarative/qdeclarativevaluetypes/tst_qdeclarativevaluetypes.cpp
+++ b/tests/auto/declarative/qdeclarativevaluetypes/tst_qdeclarativevaluetypes.cpp
@@ -93,6 +93,7 @@ private slots:
     void returnValues();
     void varAssignment();
     void bindingsSpliceCorrectly();
+    void nonValueTypeComparison();
 
 private:
     QDeclarativeEngine engine;
@@ -1301,6 +1302,18 @@ void tst_qdeclarativevaluetypes::bindingsSpliceCorrectly()
     }
 }
 
+void tst_qdeclarativevaluetypes::nonValueTypeComparison()
+{
+    QDeclarativeComponent component(&engine, testFileUrl("nonValueTypeComparison.qml"));
+    QObject *object = component.create();
+    QVERIFY(object != 0);
+
+    QCOMPARE(object->property("test1").toBool(), true);
+    QCOMPARE(object->property("test2").toBool(), true);
+
+    delete object;
+}
+
 QTEST_MAIN(tst_qdeclarativevaluetypes)
 
 #include "tst_qdeclarativevaluetypes.moc"
-- 
2.7.4