Allow partial creation of more than 10 QQmlComponent instances

The recursion detection in QQmlComponent erroneously triggered when
calling beginCreate() on >= 10 different instances. This may happen by
intention and is not necessarily a sign of recursion.

Since beginCreate() does never invoke a potentially nested
Qt.createComponent(), but completeCreate() does, it is better to
modify the creationDepth counter in completeCreate(). This also leads
to simpler code.

The test, however, can remain in beginCreate().

Task-number: QTBUG-47633
Change-Id: If413a8b08421d321d6a426ec16600996cb3f6ea1
Reviewed-by: Matthew Vogt <matthew.vogt@qinetic.com.au>
Reviewed-by: Michael Brasser <michael.brasser@live.com>
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 24 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp b/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
index 6a0dc28ca4..0263115db8 100644
--- a/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
+++ b/tests/auto/qml/qqmlcomponent/tst_qqmlcomponent.cpp
@@ -116,6 +116,7 @@ private slots:
     void onDestructionCount();
     void recursion();
     void recursionContinuation();
+    void partialComponentCreation();
     void callingContextForInitialProperties();
     void relativeUrl_data();
     void relativeUrl();
@@ -526,6 +527,29 @@ void tst_qqmlcomponent::recursionContinuation()
     QVERIFY(object->property("success").toBool());
 }
 
+void tst_qqmlcomponent::partialComponentCreation()
+{
+    const int maxCount = 17;
+    QQmlEngine engine;
+    QScopedPointer<QQmlComponent> components[maxCount];
+    QScopedPointer<QObject> objects[maxCount];
+    QQmlTestMessageHandler messageHandler;
+
+    QCOMPARE(engine.outputWarningsToStandardError(), true);
+
+    for (int i = 0; i < maxCount; i++) {
+        components[i].reset(new QQmlComponent(&engine, testFileUrl("QtObjectComponent.qml")));
+        objects[i].reset(components[i]->beginCreate(engine.rootContext()));
+        QVERIFY(objects[i].isNull() == false);
+    }
+    QVERIFY2(messageHandler.messages().isEmpty(), qPrintable(messageHandler.messageString()));
+
+    for (int i = 0; i < maxCount; i++) {
+        components[i]->completeCreate();
+    }
+    QVERIFY2(messageHandler.messages().isEmpty(), qPrintable(messageHandler.messageString()));
+}
+
 class CallingContextCheckingClass : public QObject
 {
     Q_OBJECT