TreeModel: More API cleanup

- introduce topLevelItemCount (similar to QTreeWidget)
- squash untypedTreeLevelItems()
- rename removeItems() to clear()
- rename removeItem() to takeItem()
- rename treeLevelItems<> to itemsAtLevel<>

Change-Id: I0f1bb4110f7687b20da3d92e3d943858645a9fa2
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/libs/extensionsystem/pluginview.cpp

@@ -392,7 +392,7 @@ PluginSpec *PluginView::pluginForIndex(const QModelIndex &index) const
 void PluginView::updatePlugins()
 {
     // Model.
-    m_model->removeItems();
+    m_model->clear();
 
     PluginCollection *defaultCollection = 0;
     QList<CollectionItem *> collections;

src/libs/utils/treemodel.cpp

@@ -984,6 +984,11 @@ TreeItem *TreeModel::rootItem() const
     return m_root;
 }
 
+int TreeModel::topLevelItemCount() const
+{
+    return m_root->childCount();
+}
+
 void TreeModel::setRootItem(TreeItem *item)
 {
     delete m_root;
@@ -1030,25 +1035,22 @@ QModelIndex TreeModel::indexForItem(const TreeItem *item) const
     return createIndex(row, 0, mitem);
 }
 
-void TreeModel::removeItems()
+/*!
+  Destroys all items in them model except the invisible root item.
+*/
+void TreeModel::clear()
 {
     if (m_root)
         m_root->removeChildren();
 }
 
-UntypedTreeLevelItems TreeModel::untypedLevelItems(int level, TreeItem *start) const
-{
-    if (start == 0)
-        start = m_root;
-    return UntypedTreeLevelItems(start, level);
-}
+/*!
+   Removes the specified item from the model.
 
-UntypedTreeLevelItems TreeModel::untypedLevelItems(TreeItem *start) const
-{
-    return UntypedTreeLevelItems(start, 1);
-}
+   \note The item is not destroyed, ownership is effectively passed to the caller.
+   */
 
-void TreeModel::removeItem(TreeItem *item)
+void TreeModel::takeItem(TreeItem *item)
 {
 #if USE_MODEL_TEST
     (void) new ModelTest(this, this);

src/libs/utils/treemodel.h

@@ -99,6 +99,8 @@ public:
     void setLazy(bool on);
     void setPopulated(bool on);
     void setFlags(Qt::ItemFlags flags);
+    int childCount() const { return m_children.size(); }
+    TreeItem *childAt(int index) const { return m_children.at(index); }
     QVector<TreeItem *> children() const { return m_children; }
     QModelIndex index() const;
 
@@ -258,8 +260,17 @@ class QTCREATOR_UTILS_EXPORT TreeModel : public QAbstractItemModel
 public:
     explicit TreeModel(QObject *parent = 0);
     explicit TreeModel(TreeItem *root, QObject *parent = 0);
-    virtual ~TreeModel();
+    ~TreeModel();
 
+    void setHeader(const QStringList &displays);
+    void clear();
+
+    TreeItem *rootItem() const;
+    void setRootItem(TreeItem *item);
+    TreeItem *itemForIndex(const QModelIndex &) const;
+    QModelIndex indexForItem(const TreeItem *needle) const;
+
+    int topLevelItemCount() const;
     int rowCount(const QModelIndex &idx = QModelIndex()) const;
     int columnCount(const QModelIndex &idx) const;
 
@@ -274,36 +285,19 @@ public:
     bool canFetchMore(const QModelIndex &idx) const;
     void fetchMore(const QModelIndex &idx);
 
-    TreeItem *rootItem() const;
-    void setRootItem(TreeItem *item);
-    TreeItem *itemForIndex(const QModelIndex &) const;
-    QModelIndex indexForItem(const TreeItem *needle) const;
-    void removeItems();
-
-    void setHeader(const QStringList &displays);
-
-    UntypedTreeLevelItems untypedLevelItems(int level = 0, TreeItem *start = 0) const;
-    UntypedTreeLevelItems untypedLevelItems(TreeItem *start) const;
-
     template <class T>
-    TreeLevelItems<T> treeLevelItems(int level, TreeItem *start = 0) const
+    TreeLevelItems<T> itemsAtLevel(int level, TreeItem *start = 0) const
     {
-        return TreeLevelItems<T>(untypedLevelItems(level, start));
-    }
-
-    template <class T>
-    TreeLevelItems<T> treeLevelItems(TreeItem *start) const
-    {
-        return TreeLevelItems<T>(untypedLevelItems(start));
+        return TreeLevelItems<T>(UntypedTreeLevelItems(start ? start : m_root, level));
     }
 
     template <class T>
     T findItemAtLevel(int level, std::function<bool(T)> f, TreeItem *start = 0) const
     {
-        return Utils::findOrDefault(treeLevelItems<T>(level, start), f);
+        return Utils::findOrDefault(itemsAtLevel<T>(level, start), f);
     }
 
-    void removeItem(TreeItem *item); // item is not destroyed.
+    void takeItem(TreeItem *item); // item is not destroyed.
 
 signals:
     void requestExpansion(QModelIndex);

src/plugins/cmakeprojectmanager/cmakesettingspage.cpp

@@ -237,7 +237,7 @@ void CMakeToolItemModel::removeCMakeTool(const Core::Id &id)
     CMakeToolTreeItem *treeItem = cmakeToolItem(id);
     QTC_ASSERT(treeItem, return);
 
-    removeItem(treeItem);
+    takeItem(treeItem);
     m_removedItems.append(id);
 
     delete treeItem;
@@ -248,7 +248,7 @@ void CMakeToolItemModel::apply()
     foreach (const Core::Id &id, m_removedItems)
         CMakeToolManager::deregisterCMakeTool(id);
 
-    foreach (auto item, treeLevelItems<CMakeToolTreeItem *>(2)) {
+    foreach (auto item, itemsAtLevel<CMakeToolTreeItem *>(2)) {
         item->m_changed = false;
 
         bool isNew = false;
@@ -300,7 +300,7 @@ void CMakeToolItemModel::setDefaultItemId(const Core::Id &id)
 QString CMakeToolItemModel::uniqueDisplayName(const QString &base) const
 {
     QStringList names;
-    foreach (CMakeToolTreeItem *item, treeLevelItems<CMakeToolTreeItem *>(2))
+    foreach (CMakeToolTreeItem *item, itemsAtLevel<CMakeToolTreeItem *>(2))
         names << item->m_name;
 
     return ProjectExplorer::Project::makeUnique(base, names);

src/plugins/debugger/breakhandler.cpp

@@ -401,7 +401,7 @@ void BreakHandler::deletionHelper(BreakpointModelId id)
 {
     Breakpoint b = breakpointById(id);
     QTC_ASSERT(b, return);
-    removeItem(b.b);
+    takeItem(b.b);
     delete b.b;
 }
 
@@ -1132,7 +1132,7 @@ void BreakHandler::saveSessionData()
 
 void BreakHandler::loadSessionData()
 {
-    removeItems();
+    clear();
     loadBreakpoints();
 }
 
@@ -1216,7 +1216,7 @@ void BreakHandler::changeLineNumberFromMarkerHelper(BreakpointModelId id)
     Breakpoint b = breakpointById(id);
     QTC_ASSERT(b, return);
     BreakpointParameters params = b.parameters();
-    removeItem(b.b);
+    takeItem(b.b);
     delete b.b;
     appendBreakpoint(params);
 }

src/plugins/debugger/cdb/cdbengine.cpp

@@ -1875,7 +1875,7 @@ void CdbEngine::handleLocals(const CdbResponse &response, bool newFrame)
 
         QSet<QByteArray> toDelete;
         if (newFrame) {
-            foreach (WatchItem *item, handler->model()->treeLevelItems<WatchItem *>(2))
+            foreach (WatchItem *item, handler->model()->itemsAtLevel<WatchItem *>(2))
                 toDelete.insert(item->iname);
         }
 

src/plugins/debugger/debuggerengine.cpp

@@ -1944,7 +1944,7 @@ void DebuggerEngine::updateLocalsView(const GdbMi &all)
 
     QSet<QByteArray> toDelete;
     if (!partial) {
-        foreach (WatchItem *item, handler->model()->treeLevelItems<WatchItem *>(2))
+        foreach (WatchItem *item, handler->model()->itemsAtLevel<WatchItem *>(2))
             toDelete.insert(item->iname);
     }
 

src/plugins/debugger/debuggeroptionspage.cpp

@@ -165,7 +165,7 @@ void DebuggerItemModel::removeCurrentDebugger()
     QVariant id = m_currentTreeItem->m_item.id();
     DebuggerTreeItem *treeItem = m_currentTreeItem;
     m_currentTreeItem = 0;
-    removeItem(treeItem);
+    takeItem(treeItem);
     delete treeItem;
     m_removedItems.append(id);
 }
@@ -175,7 +175,7 @@ void DebuggerItemModel::apply()
     foreach (const QVariant &id, m_removedItems)
         DebuggerItemManager::deregisterDebugger(id);
 
-    foreach (auto item, treeLevelItems<DebuggerTreeItem *>(2)) {
+    foreach (auto item, itemsAtLevel<DebuggerTreeItem *>(2)) {
         item->m_changed = false;
         DebuggerItemManager::updateOrAddDebugger(item->m_item);
     }

src/plugins/debugger/debuggertooltipmanager.cpp

@@ -199,7 +199,7 @@ public:
     ToolTipWatchItem(WatchItem *item);
 
     bool hasChildren() const { return expandable; }
-    bool canFetchMore() const { return children().isEmpty() && expandable && model(); }
+    bool canFetchMore() const { return childCount() == 0 && expandable && model(); }
     void fetchMore() {}
     QVariant data(int column, int role) const;
 

src/plugins/debugger/moduleshandler.cpp

@@ -197,7 +197,7 @@ QAbstractItemModel *ModulesHandler::model() const
 
 void ModulesHandler::removeAll()
 {
-    m_model->removeItems();
+    m_model->clear();
 }
 
 Modules ModulesHandler::modules() const
@@ -212,7 +212,7 @@ Modules ModulesHandler::modules() const
 void ModulesHandler::removeModule(const QString &modulePath)
 {
     if (ModuleItem *item = moduleFromPath(m_model->rootItem(), modulePath))
-        m_model->removeItem(item);
+        m_model->takeItem(item);
 }
 
 void ModulesHandler::updateModule(const Module &module)
@@ -254,7 +254,7 @@ void ModulesHandler::endUpdateAll()
     for (int i = root->rowCount(); --i >= 0; ) {
         auto item = static_cast<ModuleItem *>(root->child(i));
         if (!item->updated)
-            m_model->removeItem(item);
+            m_model->takeItem(item);
     }
 }
 

src/plugins/debugger/pdb/pdbengine.cpp

@@ -572,7 +572,7 @@ void PdbEngine::refreshLocals(const GdbMi &vars)
     handler->resetValueCache();
 
     QSet<QByteArray> toDelete;
-    foreach (WatchItem *item, handler->model()->treeLevelItems<WatchItem *>(2))
+    foreach (WatchItem *item, handler->model()->itemsAtLevel<WatchItem *>(2))
         toDelete.insert(item->iname);
 
     foreach (const GdbMi &child, vars.children()) {

src/plugins/debugger/watchhandler.cpp

@@ -1241,7 +1241,7 @@ void WatchModel::insertItem(WatchItem *item)
 {
     WatchItem *existing = findItem(item->iname);
     if (existing)
-        removeItem(existing);
+        takeItem(existing);
 
     //item->walkTree([item](TreeItem *sub) { sub->sortChildren(&watchItemSorter); });
     item->sortChildren(&watchItemSorter);
@@ -1308,7 +1308,7 @@ void WatchHandler::purgeOutdatedItems(const QSet<QByteArray> &inames)
 {
     foreach (const QByteArray &iname, inames) {
         WatchItem *item = findItem(iname);
-        m_model->removeItem(item);
+        m_model->takeItem(item);
     }
 
     m_model->layoutChanged();
@@ -1326,7 +1326,7 @@ void WatchHandler::removeItemByIName(const QByteArray &iname)
         theWatcherNames.remove(item->exp);
         saveWatchers();
     }
-    m_model->removeItem(item);
+    m_model->takeItem(item);
     delete item;
     updateWatchersWindow();
 }
@@ -1492,7 +1492,7 @@ void WatchHandler::updateWatchersWindow()
 
     // Force show/hide of watchers and return view.
     int showWatch = !theWatcherNames.isEmpty();
-    int showReturn = !m_model->m_returnRoot->children().isEmpty();
+    int showReturn = m_model->m_returnRoot->childCount() != 0;
     Internal::updateWatchersWindow(showWatch, showReturn);
 }
 

src/plugins/projectexplorer/kitmodel.cpp

@@ -192,8 +192,8 @@ void KitModel::isAutoDetectedChanged()
 
     if (oldParent && oldParent != newParent) {
         beginMoveRows(indexForItem(oldParent), idx, idx, indexForItem(newParent), newParent->children().size());
-        TreeItem *n = oldParent->children().at(idx);
-        removeItem(n);
+        TreeItem *n = oldParent->childAt(idx);
+        takeItem(n);
         newParent->appendChild(n);
         endMoveRows();
     }
@@ -202,7 +202,7 @@ void KitModel::isAutoDetectedChanged()
 void KitModel::validateKitNames()
 {
     QHash<QString, int> nameHash;
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         const QString displayName = n->widget->displayName();
         if (nameHash.contains(displayName))
             ++nameHash[displayName];
@@ -210,7 +210,7 @@ void KitModel::validateKitNames()
             nameHash.insert(displayName, 1);
     }
 
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         const QString displayName = n->widget->displayName();
         n->widget->setHasUniqueName(nameHash.value(displayName) == 1);
     }
@@ -223,7 +223,7 @@ void KitModel::apply()
         n->widget->removeKit();
 
     // Update kits:
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         if (n->widget->isDirty()) {
             n->widget->apply();
             n->update();
@@ -249,7 +249,7 @@ void KitModel::markForRemoval(Kit *k)
     if (node == m_defaultNode)
         setDefaultNode(findItemAtLevel<KitNode *>(2, [node](KitNode *kn) { return kn != node; }));
 
-    removeItem(node);
+    takeItem(node);
     if (node->widget->configures(0))
         delete node;
     else
@@ -279,7 +279,7 @@ Kit *KitModel::markForAddition(Kit *baseKit)
 
 KitNode *KitModel::findWorkingCopy(Kit *k) const
 {
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         if (n->widget->workingCopy() == k)
             return n;
     }
@@ -349,7 +349,7 @@ void KitModel::removeKit(Kit *k)
     }
 
     KitNode *node = 0;
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         if (n->widget->configures(k)) {
             node = n;
             break;
@@ -359,7 +359,7 @@ void KitModel::removeKit(Kit *k)
     if (node == m_defaultNode)
         setDefaultNode(findItemAtLevel<KitNode *>(2, [node](KitNode *kn) { return kn != node; }));
 
-    removeItem(node);
+    takeItem(node);
     delete node;
 
     validateKitNames();
@@ -369,7 +369,7 @@ void KitModel::removeKit(Kit *k)
 void KitModel::changeDefaultKit()
 {
     Kit *defaultKit = KitManager::defaultKit();
-    foreach (KitNode *n, treeLevelItems<KitNode *>(2)) {
+    foreach (KitNode *n, itemsAtLevel<KitNode *>(2)) {
         if (n->widget->configures(defaultKit)) {
             setDefaultNode(n);
             return;

src/plugins/projectexplorer/toolchainoptionspage.cpp

@@ -219,7 +219,7 @@ public:
 
 void ToolChainOptionsWidget::markForRemoval(ToolChainTreeItem *item)
 {
-    m_model.removeItem(item);
+    m_model.takeItem(item);
     if (m_toAddList.contains(item)) {
         delete item->toolChain;
         item->toolChain = 0;
@@ -257,9 +257,9 @@ void ToolChainOptionsWidget::removeToolChain(ToolChain *tc)
     }
 
     TreeItem *parent = m_model.rootItem()->child(tc->isAutoDetected() ? 0 : 1);
-    foreach (ToolChainTreeItem *item, m_model.treeLevelItems<ToolChainTreeItem *>(1, parent)) {
+    foreach (ToolChainTreeItem *item, m_model.itemsAtLevel<ToolChainTreeItem *>(1, parent)) {
         if (item->toolChain == tc) {
-            m_model.removeItem(item);
+            m_model.takeItem(item);
             delete item;
             break;
         }
@@ -292,7 +292,7 @@ void ToolChainOptionsWidget::apply()
     Q_ASSERT(m_toRemoveList.isEmpty());
 
     // Update tool chains:
-    foreach (ToolChainTreeItem *item, m_model.treeLevelItems<ToolChainTreeItem *>(1, m_manualRoot)) {
+    foreach (ToolChainTreeItem *item, m_model.itemsAtLevel<ToolChainTreeItem *>(1, m_manualRoot)) {
         if (item->changed) {
             Q_ASSERT(item->toolChain);
             if (item->widget)

tests/auto/utils/treemodel/tst_treemodel.cpp

@@ -47,7 +47,7 @@ private slots:
 static int countLevelItems(TreeItem *base, int level)
 {
     int n = 0;
-    foreach (TreeItem *item, base->model()->untypedLevelItems(level, base)) {
+    foreach (TreeItem *item, base->model()->untypedItemsAtLevel(level, base)) {
         Q_UNUSED(item);
         ++n;
     }