Simplify expression guard logic

Change-Id: I7d191bc8786452c5a1f14d024ff62d223adebd8b
Reviewed-by: Martin Jones <martin.jones@nokia.com>
Reviewed-by: Aaron Kennedy <aaron.kennedy@nokia.com>

4 files changed, 42 insertions, 0 deletions

diff --git a/tests/auto/declarative/qdeclarativeecmascript/data/doubleEvaluate.qml b/tests/auto/declarative/qdeclarativeecmascript/data/doubleEvaluate.qml
new file mode 100644
index 0000000000..0532715432
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeecmascript/data/doubleEvaluate.qml
@@ -0,0 +1,6 @@
+import Qt.test 1.0
+
+WriteCounter {
+    property int x: 0
+    value: if (1) x + x
+}
diff --git a/tests/auto/declarative/qdeclarativeecmascript/testtypes.cpp b/tests/auto/declarative/qdeclarativeecmascript/testtypes.cpp
index 5bd0287c1b..513705d697 100644
--- a/tests/auto/declarative/qdeclarativeecmascript/testtypes.cpp
+++ b/tests/auto/declarative/qdeclarativeecmascript/testtypes.cpp
@@ -195,6 +195,7 @@ void registerTypes()
     qmlRegisterType<CircularReferenceHandle>("Qt.test", 1, 0, "CircularReferenceHandle");
 
     qmlRegisterType<MyDynamicCreationDestructionObject>("Qt.test", 1, 0, "MyDynamicCreationDestructionObject");
+    qmlRegisterType<WriteCounter>("Qt.test", 1, 0, "WriteCounter");
 }
 
 #include "testtypes.moc"
diff --git a/tests/auto/declarative/qdeclarativeecmascript/testtypes.h b/tests/auto/declarative/qdeclarativeecmascript/testtypes.h
index 5357a63678..7684ddd438 100644
--- a/tests/auto/declarative/qdeclarativeecmascript/testtypes.h
+++ b/tests/auto/declarative/qdeclarativeecmascript/testtypes.h
@@ -1131,6 +1131,23 @@ private:
     int *m_dtorCount;
 };
 
+class WriteCounter : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(int value READ value WRITE setValue);
+public:
+    WriteCounter() : m_value(0), m_count(0) {}
+
+    int value() const { return m_value; }
+    void setValue(int v) { m_value = v; ++m_count; }
+
+    int count() const { return m_count; }
+
+private:
+    int m_value;
+    int m_count;
+};
+
 void registerTypes();
 
 #endif // TESTTYPES_H
diff --git a/tests/auto/declarative/qdeclarativeecmascript/tst_qdeclarativeecmascript.cpp b/tests/auto/declarative/qdeclarativeecmascript/tst_qdeclarativeecmascript.cpp
index 3feecfc2ac..4f1cdccc04 100644
--- a/tests/auto/declarative/qdeclarativeecmascript/tst_qdeclarativeecmascript.cpp
+++ b/tests/auto/declarative/qdeclarativeecmascript/tst_qdeclarativeecmascript.cpp
@@ -207,6 +207,7 @@ private slots:
     void dynamicString();
     void include();
     void signalHandlers();
+    void doubleEvaluate();
 
     void callQtInvokables();
     void invokableObjectArg();
@@ -4763,6 +4764,23 @@ void tst_qdeclarativeecmascript::automaticSemicolon()
     QVERIFY(object != 0);
 }
 
+// Makes sure that a binding isn't double re-evaluated when it depends on the same variable twice
+void tst_qdeclarativeecmascript::doubleEvaluate()
+{
+    QDeclarativeComponent component(&engine, TEST_FILE("doubleEvaluate.qml"));
+    QObject *object = component.create();
+    QVERIFY(object != 0);
+    WriteCounter *wc = qobject_cast<WriteCounter *>(object);
+    QVERIFY(wc != 0);
+    QCOMPARE(wc->count(), 1);
+
+    wc->setProperty("x", 9);
+
+    QCOMPARE(wc->count(), 2);
+
+    delete object;
+}
+
 QTEST_MAIN(tst_qdeclarativeecmascript)
 
 #include "tst_qdeclarativeecmascript.moc"