Handle corner case of assigning an implicit page to a new view

Pass the ownership on to the the new view, so it is still handled like
an implicit page.

Change-Id: I76ad3cb349a492e60e3ad2bdd4aebaabed07bd4f
Reviewed-by: Jüri Valdmann <juri.valdmann@qt.io>

2 files changed, 28 insertions, 9 deletions

diff --git a/src/webenginewidgets/api/qwebenginepage.cpp b/src/webenginewidgets/api/qwebenginepage.cpp
index 85a162383..54006169e 100644
--- a/src/webenginewidgets/api/qwebenginepage.cpp
+++ b/src/webenginewidgets/api/qwebenginepage.cpp
@@ -746,17 +746,26 @@ void QWebEnginePagePrivate::bindPageAndView(QWebEnginePage *page, QWebEngineView
     auto oldView = page ? page->d_func()->view : nullptr;
     auto oldPage = view ? view->d_func()->page : nullptr;
 
+    bool ownNewPage = false;
+    bool deleteOldPage = false;
+
     // Change pointers first.
 
     if (page && oldView != view) {
-        if (oldView)
+        if (oldView) {
+            ownNewPage = oldView->d_func()->m_ownsPage;
             oldView->d_func()->page = nullptr;
+            oldView->d_func()->m_ownsPage = false;
+        }
         page->d_func()->view = view;
     }
 
     if (view && oldPage != page) {
-        if (oldPage)
+        if (oldPage) {
             oldPage->d_func()->view = nullptr;
+            deleteOldPage = view->d_func()->m_ownsPage;
+        }
+        view->d_func()->m_ownsPage = ownNewPage;
         view->d_func()->page = page;
     }
 
@@ -775,14 +784,9 @@ void QWebEnginePagePrivate::bindPageAndView(QWebEnginePage *page, QWebEngineView
         view->d_func()->pageChanged(oldPage, page);
         if (oldWidget != widget)
             view->d_func()->widgetChanged(oldWidget, widget);
-
-        // At this point m_ownsPage should still refer to oldPage,
-        // it is only set for the new page after binding.
-        if (view->d_func()->m_ownsPage) {
-            delete oldPage;
-            view->d_func()->m_ownsPage = false;
-        }
     }
+    if (deleteOldPage)
+        delete oldPage;
 }
 
 void QWebEnginePagePrivate::bindPageAndWidget(QWebEnginePage *page, RenderWidgetHostViewQtDelegateWidget *widget)
diff --git a/tests/auto/widgets/qwebengineview/tst_qwebengineview.cpp b/tests/auto/widgets/qwebengineview/tst_qwebengineview.cpp
index 6ab63b54e..b9337cbee 100644
--- a/tests/auto/widgets/qwebengineview/tst_qwebengineview.cpp
+++ b/tests/auto/widgets/qwebengineview/tst_qwebengineview.cpp
@@ -196,6 +196,7 @@ private Q_SLOTS:
     void closeOpenerTab();
     void switchPage();
     void setPageDeletesImplicitPage();
+    void setPageDeletesImplicitPage2();
     void setViewDeletesImplicitPage();
     void setPagePreservesExplicitPage();
     void setViewPreservesExplicitPage();
@@ -3210,6 +3211,20 @@ void tst_QWebEngineView::setPageDeletesImplicitPage()
     QVERIFY(!implicitPage); // should be deleted
 }
 
+void tst_QWebEngineView::setPageDeletesImplicitPage2()
+{
+    QWebEngineView view1;
+    QWebEngineView view2;
+    QPointer<QWebEnginePage> implicitPage = view1.page();
+    view2.setPage(view1.page());
+    QVERIFY(implicitPage);
+    QVERIFY(view1.page() != implicitPage);
+    QWebEnginePage explicitPage;
+    view2.setPage(&explicitPage);
+    QCOMPARE(view2.page(), &explicitPage);
+    QVERIFY(!implicitPage); // should be deleted
+}
+
 void tst_QWebEngineView::setViewDeletesImplicitPage()
 {
     QWebEngineView view;