QTreeView: speedup isFirstColumnSpanned/setFirstColumnSpanned

Change container of spanningIndexes from QVector to QSet to speedup
the isFirstColumnSpanned/setFirstColumnSpanned. The order of the indexes
in the container is not needed and therefore QSet can be used here.
This also simplifies the code a little bit.

Task-number: QTBUG-66714
Change-Id: I1692ca1df751b2b8d26b607faf60ff2b94f6f964
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

2 files changed, 8 insertions, 17 deletions

diff --git a/src/widgets/itemviews/qtreeview.cpp b/src/widgets/itemviews/qtreeview.cpp
index 4a02f30822..4b1c4c3e90 100644
--- a/src/widgets/itemviews/qtreeview.cpp
+++ b/src/widgets/itemviews/qtreeview.cpp
@@ -632,11 +632,8 @@ bool QTreeView::isFirstColumnSpanned(int row, const QModelIndex &parent) const
     Q_D(const QTreeView);
     if (d->spanningIndexes.isEmpty() || !d->model)
         return false;
-    QModelIndex index = d->model->index(row, 0, parent);
-    for (int i = 0; i < d->spanningIndexes.count(); ++i)
-        if (d->spanningIndexes.at(i) == index)
-            return true;
-    return false;
+    const QModelIndex index = d->model->index(row, 0, parent);
+    return d->spanningIndexes.contains(index);
 }
 
 /*!
@@ -653,20 +650,14 @@ void QTreeView::setFirstColumnSpanned(int row, const QModelIndex &parent, bool s
     Q_D(QTreeView);
     if (!d->model)
         return;
-    QModelIndex index = d->model->index(row, 0, parent);
+    const QModelIndex index = d->model->index(row, 0, parent);
     if (!index.isValid())
         return;
 
-    if (span) {
-        QPersistentModelIndex persistent(index);
-        if (!d->spanningIndexes.contains(persistent))
-            d->spanningIndexes.append(persistent);
-    } else {
-        QPersistentModelIndex persistent(index);
-        int i = d->spanningIndexes.indexOf(persistent);
-        if (i >= 0)
-            d->spanningIndexes.remove(i);
-    }
+    if (span)
+        d->spanningIndexes.insert(index);
+    else
+        d->spanningIndexes.remove(index);
 
     d->executePostedLayout();
     int i = d->viewIndex(index);
diff --git a/src/widgets/itemviews/qtreeview_p.h b/src/widgets/itemviews/qtreeview_p.h
index 9a391ee88a..8b217036a2 100644
--- a/src/widgets/itemviews/qtreeview_p.h
+++ b/src/widgets/itemviews/qtreeview_p.h
@@ -247,7 +247,7 @@ public:
     void updateIndentationFromStyle();
 
     // used for spanning rows
-    QVector<QPersistentModelIndex> spanningIndexes;
+    QSet<QPersistentModelIndex> spanningIndexes;
 
     // used for updating resized columns
     int columnResizeTimerID;