b0e82f5981
Add new overloads to make sure that we can pass continuation data even for the continuations with context. The new overloads intentionally do not expose QFutureInterfaceBasePrivate pointer, because they would be used in the inline code (see QTBUG-117514). The overload with a context provides a continuation future as a QVariant, because that is the easiest way to keep the QFutureInterface<T> object alive without exposing the template type T to a non-templated exported base class. We cannot pass the QFutureInterfaceBase because of the reference count logic, which contains two different counters: for base class (void case), and for the interface that holds an actual type T. This patch is a pre-requisite for a follow-up patch that would introduce the ability to cancel the entire continuation chain from the first QFuture object of the chain, even if that QFuture is already finished. Note that the pre-existing QFutureInterface::cancel() code relies on the fact that only then-continuations provide continuation data. The onFailed() and onCanceled() handlers never provide it, even when they were supposed to be executed in the same thread. To keep the old behavior on the cancel() method, introduce a new ContinuationType enum and make sure that the type is properly set when providing a continuation data. The new overloads also allow to get rid of the template QtPrivate::watchContinuation() helper method. The exported Impl should stay for BC reasons. This patch implements it in terms of the new setContinuation() overload. During the development of this patch it was important to verify that the behavior of all public and/or exported methods stays unchanged. It was done by running the tst_qfuture binary that was originally compiled with the old QtCore version against the updated QtCore library. Task-number: QTBUG-130662 Change-Id: I2bd5821846561d18c198205f3c57d3f0dacbb94b Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>