QQmlIntanceModel: use QQmlIncubator::IncubationMode instead of bool to specify incubation mode

The current implementation would pass a boolean to signal if asynchronous
or synchronous incubation should be used to create an item. The problem with this approach
is that passing 'synchronous" would translate to QQmlIncubation::AsynchronousIfNested
later down the chain. This meant that even if the caller requested synchronous incubation, it
could end up with asynchronous incubation anyway, e.g if an async parent incubator was active at
the time of the call. And this can easily come as an unhandled supprise for the caller, and as
such, cause unforseen bugs.

This patch is a first of a set of patches that is done to fix the bug reported in the task below.
It will not change any behavior, it is written to preserve the logic exactly as it were, just
as a preparation for subsequent patches. It makes it explicit at the call location what
incubation mode will be used, and especially make it clear whenever the AsynchronousIfNested
flag is in play.

Task-number: QTBUG-61537
Change-Id: I8b3ba5438ebb2cd59983a098bd8ceeeb844da87b
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/qml/types/qqmldelegatemodel_p_p.h b/src/qml/types/qqmldelegatemodel_p_p.h
index 0f8438870a..a6a7853116 100644
--- a/src/qml/types/qqmldelegatemodel_p_p.h
+++ b/src/qml/types/qqmldelegatemodel_p_p.h
@@ -261,7 +261,7 @@ public:
     void connectModel(QQmlAdaptorModel *model);
 
     void requestMoreIfNecessary();
-    QObject *object(Compositor::Group group, int index, bool asynchronous);
+    QObject *object(Compositor::Group group, int index, QQmlIncubator::IncubationMode incubationMode);
     QQmlDelegateModel::ReleaseFlags release(QObject *object);
     QString stringValue(Compositor::Group group, int index, const QString &name);
     void emitCreatedPackage(QQDMIncubationTask *incubationTask, QQuickPackage *package);
@@ -357,7 +357,7 @@ public:
 
     int count() const override;
     bool isValid() const override;
-    QObject *object(int index, bool asynchronous = false) override;
+    QObject *object(int index, QQmlIncubator::IncubationMode incubationMode = QQmlIncubator::AsynchronousIfNested) override;
     ReleaseFlags release(QObject *item) override;
     QString stringValue(int index, const QString &role) override;
     QList<QByteArray> watchedRoles() const { return m_watchedRoles; }