Prepare tests for upcoming incremental gc

This commit:
- Introduces helper functions gcDone and gc. gcDone simply returns true
  as the gc is currently not incremental. gc is a helper method which
  has been copied into various tests already, which runs the garbage
  collections and sends events to clean up objects scheduled for
  deletion. The new helpers are placed in qmlutils.cpp.
- It adds a flag to gc which allows not sending the posted events. That
  allows using gc in more places, while highlighting the fact that we
  don't want to process events at this point. This will also help
  upcoming changes to the incremental gc, which by default will use the
  event loop to drive the gc processing
- It moves some gc calls from QML to C++ – this again will help later to
  ensure that the gc actually has completed

As a driveby, the logging rules early in tst_qv4mm are reset earlier.

Task-number: QTBUG-119274
Change-Id: I75d6ffcb3aa459b020e8257155faa91c39653d43
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 20 insertions, 40 deletions

diff --git a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
index 787bac1520..35b7e6a535 100644
--- a/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
+++ b/tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp
@@ -444,14 +444,6 @@ private:
     }
 };
 
-static void gc(QQmlEngine &engine)
-{
-    engine.collectGarbage();
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-    QCoreApplication::processEvents();
-}
-
-
 tst_qqmlecmascript::tst_qqmlecmascript()
     : QQmlDataTest(QT_QMLTEST_DATADIR)
 {
@@ -4082,10 +4074,7 @@ void tst_qqmlecmascript::ownership()
 
         QScopedPointer<QObject> object(component.create(context.data()));
 
-        engine.collectGarbage();
-
-        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-        QCoreApplication::processEvents();
+        gc(engine);
 
         QVERIFY(own.object.isNull());
     }
@@ -4099,10 +4088,7 @@ void tst_qqmlecmascript::ownership()
 
         QScopedPointer<QObject> object(component.create(context.data()));
 
-        engine.collectGarbage();
-
-        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-        QCoreApplication::processEvents();
+        gc(engine);
 
         QVERIFY(own.object != nullptr);
     }
@@ -4178,9 +4164,7 @@ void tst_qqmlecmascript::ownershipCustomReturnValue()
     QVERIFY(source.value != nullptr);
     }
 
-    engine.collectGarbage();
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-    QCoreApplication::processEvents();
+    gc(engine);
 
     QVERIFY(source.value.isNull());
 }
@@ -4211,10 +4195,7 @@ void tst_qqmlecmascript::ownershipRootObject()
     QScopedPointer<QObject> object(component.create(context.data()));
     QVERIFY2(object, qPrintable(component.errorString()));
 
-    engine.collectGarbage();
-
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-    QCoreApplication::processEvents();
+    gc(engine);
 
     QVERIFY(own.object != nullptr);
 }
@@ -4239,10 +4220,7 @@ void tst_qqmlecmascript::ownershipConsistency()
     QScopedPointer<QObject> object(component.create(context.data()));
     QVERIFY2(object, qPrintable(component.errorString()));
 
-    engine.collectGarbage();
-
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-    QCoreApplication::processEvents();
+    gc(engine);
 
     QVERIFY(own.object != nullptr);
 }
@@ -4772,6 +4750,7 @@ void tst_qqmlecmascript::verifyContextLifetime(const QQmlRefPointer<QQmlContextD
             }
 
             ctxt->engine()->collectGarbage();
+            QTRY_VERIFY(gcDone(ctxt->engine()));
             qml = scripts->get(i);
             newContext = qml ? qml->getContext() : nullptr;
             QCOMPARE(scriptContext.data(), newContext.data());
@@ -5599,7 +5578,9 @@ void tst_qqmlecmascript::propertyVarOwnership()
     QScopedPointer<QObject> object(component.create());
     QVERIFY2(object, qPrintable(component.errorString()));
     QMetaObject::invokeMethod(object.data(), "createComponent");
-    engine.collectGarbage();
+    // This test only works if we don't deliver the pending delete later event
+    // that collectGarbage will post before calling runTest
+    gc(engine, GCFlags::DontSendPostedEvents);
     QMetaObject::invokeMethod(object.data(), "runTest");
     QCOMPARE(object->property("test").toBool(), true);
     }
@@ -5615,8 +5596,7 @@ void tst_qqmlecmascript::propertyVarImplicitOwnership()
     QScopedPointer<QObject> object(component.create());
     QVERIFY2(object, qPrintable(component.errorString()));
     QMetaObject::invokeMethod(object.data(), "assignCircular");
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete); // process deleteLater() events from QV8QObjectWrapper.
-    QCoreApplication::processEvents();
+    gc(engine);
     QObject *rootObject = object->property("vp").value<QObject*>();
     QVERIFY(rootObject != nullptr);
     QObject *childObject = rootObject->findChild<QObject*>("text");
@@ -5625,6 +5605,8 @@ void tst_qqmlecmascript::propertyVarImplicitOwnership()
     QCOMPARE(childObject->property("textCanary").toInt(), 10);
     // Creates a reference to a constructed QObject:
     QMetaObject::invokeMethod(childObject, "constructQObject");
+    // Don't send delete later events yet, we do it manually later
+    gc(engine, GCFlags::DontSendPostedEvents);
     QPointer<QObject> qobjectGuard(childObject->property("vp").value<QObject*>()); // get the pointer prior to processing deleteLater events.
     QVERIFY(!qobjectGuard.isNull());
     QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete); // process deleteLater() events from QV8QObjectWrapper.
@@ -5643,8 +5625,7 @@ void tst_qqmlecmascript::propertyVarReparent()
     QScopedPointer<QObject> object(component.create());
     QVERIFY2(object, qPrintable(component.errorString()));
     QMetaObject::invokeMethod(object.data(), "assignVarProp");
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete); // process deleteLater() events from QV8QObjectWrapper.
-    QCoreApplication::processEvents();
+    gc(engine);
     QObject *rect = object->property("vp").value<QObject*>();
     QObject *text = rect->findChild<QObject*>("textOne");
     QObject *text2 = rect->findChild<QObject*>("textTwo");
@@ -5658,6 +5639,7 @@ void tst_qqmlecmascript::propertyVarReparent()
     QCOMPARE(text2->property("textCanary").toInt(), 12);
     // now construct an image which we will reparent.
     QMetaObject::invokeMethod(text2, "constructQObject");
+    gc(engine, GCFlags::DontSendPostedEvents);
     QObject *image = text2->property("vp").value<QObject*>();
     QPointer<QObject> imageGuard(image);
     QVERIFY(!imageGuard.isNull());
@@ -5685,8 +5667,7 @@ void tst_qqmlecmascript::propertyVarReparentNullContext()
     QScopedPointer<QObject> object(component.create());
     QVERIFY2(object, qPrintable(component.errorString()));
     QMetaObject::invokeMethod(object.data(), "assignVarProp");
-    QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete); // process deleteLater() events from QV8QObjectWrapper.
-    QCoreApplication::processEvents();
+    gc(engine);
     QObject *rect = object->property("vp").value<QObject*>();
     QObject *text = rect->findChild<QObject*>("textOne");
     QObject *text2 = rect->findChild<QObject*>("textTwo");
@@ -5700,6 +5681,7 @@ void tst_qqmlecmascript::propertyVarReparentNullContext()
     QCOMPARE(text2->property("textCanary").toInt(), 12);
     // now construct an image which we will reparent.
     QMetaObject::invokeMethod(text2, "constructQObject");
+    gc(engine);
     QObject *image = text2->property("vp").value<QObject*>();
     QPointer<QObject> imageGuard(image);
     QVERIFY(!imageGuard.isNull());
@@ -5926,9 +5908,7 @@ void tst_qqmlecmascript::handleReferenceManagement()
         gc(hrmEngine);
         QCOMPARE(dtorCount, 0); // second has JS ownership, kept alive by first's reference
         object.reset();
-        hrmEngine.collectGarbage();
-        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-        QCoreApplication::processEvents();
+        gc(hrmEngine);
         QCOMPARE(dtorCount, 3);
     }
 
@@ -5945,9 +5925,7 @@ void tst_qqmlecmascript::handleReferenceManagement()
         gc(hrmEngine);
         QCOMPARE(dtorCount, 2); // both should be cleaned up, since circular references shouldn't keep alive.
         object.reset();
-        hrmEngine.collectGarbage();
-        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
-        QCoreApplication::processEvents();
+        gc(hrmEngine);
         QCOMPARE(dtorCount, 3);
     }
 
@@ -8224,7 +8202,9 @@ void tst_qqmlecmascript::qqmldataDestroyed()
         QVERIFY2(object, qPrintable(c.errorString()));
         // now gc causing the collection of the dynamically constructed object.
         engine.collectGarbage();
+        QTRY_VERIFY(gcDone(&engine));
         engine.collectGarbage();
+        QTRY_VERIFY(gcDone(&engine));
         // now process events to allow deletion (calling qqmldata::destroyed())
         QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
         QCoreApplication::processEvents();