Fix JavaScript signal connect on alias without other handlers

The changed handlers for aliases are connected lazily in the engine.
QQmlPropertyPrivate::flushSignal is responsible for that and called in other
places, for example when installing a onSomeAliasPropertyChanged handler.
However we were missing a call to flushSignal when doing
onSomeAliasPropertyChanged.connect(...), i.e. using the JavaScript connect API.

Task-number: QTBUG-30493
Change-Id: Ia3f008626fd7af3f2cfbdd30d13fb83158bed4d5
Reviewed-by: Albert Astals Cid <albert.astals@canonical.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

2 files changed, 41 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlecmascript/data/signalHandlers.qml b/tests/auto/qml/qqmlecmascript/data/signalHandlers.qml
index 975be1b2ad..7e85312692 100644
--- a/tests/auto/qml/qqmlecmascript/data/signalHandlers.qml
+++ b/tests/auto/qml/qqmlecmascript/data/signalHandlers.qml
@@ -57,4 +57,38 @@ QtObject {
         if (onTestSignal !== undefined)
             definedHandlerResult = true;
     }
+
+    property QtObject objWithAlias: QtObject {
+        id: testObjectWithAlias
+
+        property int count: 0;
+        property alias countAlias: testObjectWithAlias.count
+    }
+
+    function testConnectionOnAlias() {
+        var called = false;
+
+        testObjectWithAlias.onCountAliasChanged.connect(function() {
+            called = true
+        })
+
+        testObjectWithAlias.count++;
+        return called;
+    }
+
+    property QtObject objWithAliasHandler: QtObject {
+        id: testObjectWithAliasHandler
+
+        property bool testSuccess: false
+
+        property int count: 0
+        property alias countAlias: testObjectWithAliasHandler.count
+        onCountAliasChanged: testSuccess = true
+    }
+
+    function testAliasSignalHandler() {
+        testObjectWithAliasHandler.testSuccess = false
+        testObjectWithAliasHandler.count++
+        return testObjectWithAliasHandler.testSuccess
+    }
 }
diff --git a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
index 6b19c13109..660be13f71 100644
--- a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
+++ b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
@@ -6060,6 +6060,13 @@ void tst_qqmlecmascript::signalHandlers()
     QMetaObject::invokeMethod(o, "testSignalHandlerDefined");
     QCOMPARE(o->property("definedHandlerResult").toBool(), true);
 
+    QVariant result;
+    QMetaObject::invokeMethod(o, "testConnectionOnAlias", Q_RETURN_ARG(QVariant, result));
+    QCOMPARE(result.toBool(), true);
+
+    QMetaObject::invokeMethod(o, "testAliasSignalHandler", Q_RETURN_ARG(QVariant, result));
+    QCOMPARE(result.toBool(), true);
+
     delete o;
 }