Remove bool trap in QDockWidgetPrivate::endDrag()

endDrag(false) meant to end a drag with a dock location change.
endDrag(true) meant to abort a drag without a dock location change.

Replace this with a meaningful enumeration.
Define a dummy enum for builds w/o QDockWidget.

Task-number: QTBUG-118578
Task-number: QTBUG-118579
Pick-to: 6.6 6.5
Change-Id: I786f4210f5a3ee67ffcf0dc9285f77a480148569
Reviewed-by: David Faure <david.faure@kdab.com>

src/widgets/widgets/qdockwidget.cpp

@@ -792,7 +792,7 @@ void QDockWidgetPrivate::startDrag(DragScope scope)
             delete state;
             state = nullptr;
         } else {
-            endDrag();
+            endDrag(QDockWidgetPrivate::EndDragMode::LocationChange);
         }
     }
 #endif
@@ -803,7 +803,7 @@ void QDockWidgetPrivate::startDrag(DragScope scope)
     The \a abort parameter specifies that it ends because of programmatic state
     reset rather than mouse release event.
  */
-void QDockWidgetPrivate::endDrag(bool abort)
+void QDockWidgetPrivate::endDrag(EndDragMode mode)
 {
     Q_Q(QDockWidget);
     Q_ASSERT(state != nullptr);
@@ -815,7 +815,7 @@ void QDockWidgetPrivate::endDrag(bool abort)
         Q_ASSERT(mainWindow != nullptr);
         QMainWindowLayout *mwLayout = qt_mainwindow_layout(mainWindow);
 
-        if (abort || !mwLayout->plug(state->widgetItem)) {
+        if (mode == EndDragMode::Abort || !mwLayout->plug(state->widgetItem)) {
             if (hasFeature(this, QDockWidget::DockWidgetFloatable)) {
                 // This QDockWidget will now stay in the floating state.
                 if (state->ownWidgetItem) {
@@ -1050,7 +1050,7 @@ bool QDockWidgetPrivate::mouseReleaseEvent(QMouseEvent *event)
 #endif
 
     if (event->button() == Qt::LeftButton && state && !state->nca) {
-        endDrag();
+        endDrag(EndDragMode::LocationChange);
         return true; //filter out the event
     }
 
@@ -1096,15 +1096,14 @@ void QDockWidgetPrivate::nonClientAreaMouseEvent(QMouseEvent *event)
                 break;
 
 #if !defined(Q_OS_MAC) && !defined(Q_OS_WASM)
-            if (state->nca) {
-                endDrag();
-            }
+            if (state->nca)
+                endDrag(EndDragMode::LocationChange);
 #endif
             break;
         case QEvent::NonClientAreaMouseButtonRelease:
 #if defined(Q_OS_MAC) || defined(Q_OS_WASM)
                         if (state)
-                                endDrag();
+                            endDrag(EndDragMode::LocationChange);
 #endif
                         break;
         case QEvent::NonClientAreaMouseButtonDblClick:
@@ -1432,7 +1431,7 @@ void QDockWidget::setFloating(bool floating)
 
     // the initial click of a double-click may have started a drag...
     if (d->state != nullptr)
-        d->endDrag(true);
+        d->endDrag(QDockWidgetPrivate::EndDragMode::Abort);
 
     QRect r = d->undockedGeometry;
     // Keep position when undocking for the first time.
@@ -1520,7 +1519,7 @@ void QDockWidget::closeEvent(QCloseEvent *event)
 {
     Q_D(QDockWidget);
     if (d->state)
-        d->endDrag(true);
+        d->endDrag(QDockWidgetPrivate::EndDragMode::Abort);
 
     // For non-closable widgets, don't allow closing, except when the mainwindow
     // is hidden, as otherwise an application wouldn't be able to be shut down.

src/widgets/widgets/qdockwidget_p.h

@@ -56,6 +56,11 @@ public:
         Widget
     };
 
+    enum class EndDragMode {
+        LocationChange,
+        Abort
+    };
+
     void init();
     void toggleView(bool);
     void toggleTopLevel();
@@ -92,7 +97,7 @@ public:
     void nonClientAreaMouseEvent(QMouseEvent *event);
     void initDrag(const QPoint &pos, bool nca);
     void startDrag(DragScope scope);
-    void endDrag(bool abort = false);
+    void endDrag(EndDragMode mode);
     void moveEvent(QMoveEvent *event);
     void recalculatePressPos(QResizeEvent *event);
 

src/widgets/widgets/qmainwindowlayout.cpp

@@ -1821,9 +1821,9 @@ void QMainWindowTabBar::mouseReleaseEvent(QMouseEvent *e)
 {
     if (draggingDock && e->button() == Qt::LeftButton) {
         QDockWidgetPrivate *dockPriv = static_cast<QDockWidgetPrivate *>(QObjectPrivate::get(draggingDock));
-        if (dockPriv->state && dockPriv->state->dragging) {
-            dockPriv->endDrag();
-        }
+        if (dockPriv->state && dockPriv->state->dragging)
+            dockPriv->endDrag(QDockWidgetPrivate::EndDragMode::LocationChange);
+
         draggingDock = nullptr;
     }
     QTabBar::mouseReleaseEvent(e);