Autotest: Introduce ItemDataCache

Change-Id: Icbd703a8ddd3c5dea4a90d2c32c1866764bc0267
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

4 files changed, 57 insertions, 49 deletions

diff --git a/src/plugins/autotest/testnavigationwidget.cpp b/src/plugins/autotest/testnavigationwidget.cpp
index f3195c873b..31b0c6749b 100644
--- a/src/plugins/autotest/testnavigationwidget.cpp
+++ b/src/plugins/autotest/testnavigationwidget.cpp
@@ -111,7 +111,6 @@ TestNavigationWidget::TestNavigationWidget(QWidget *parent) :
     connect(sm, &ProjectExplorer::SessionManager::startupProjectChanged,
             this, [this](ProjectExplorer::Project * /*project*/) {
         m_expandedStateCache.clear();
-        m_itemUseCache.clear();
     });
     connect(m_model, &TestTreeModel::testTreeModelChanged,
             this, &TestNavigationWidget::reapplyCachedExpandedState);
@@ -237,22 +236,12 @@ QList<QToolButton *> TestNavigationWidget::createToolButtons()
 
 void TestNavigationWidget::updateExpandedStateCache()
 {
-    // raise generation for cached items and drop anything reaching 10th generation
-    const QList<QString> cachedNames = m_itemUseCache.keys();
-    for (const QString &cachedName : cachedNames) {
-        auto it = m_itemUseCache.find(cachedName);
-        if (it.value()++ >= 10) {
-            m_itemUseCache.erase(it);
-            m_expandedStateCache.remove(cachedName);
-        }
-    }
+    m_expandedStateCache.evolve();
 
     for (Utils::TreeItem *rootNode : *m_model->rootItem()) {
         rootNode->forAllChildren([this](Utils::TreeItem *child) {
-            auto childItem = static_cast<TestTreeItem *>(child);
-            const QString cacheName = childItem->cacheName();
-            m_expandedStateCache.insert(cacheName, m_view->isExpanded(childItem->index()));
-            m_itemUseCache[cacheName] = 0; // explicitly mark as 0-generation
+            m_expandedStateCache.insert(static_cast<TestTreeItem *>(child),
+                                        m_view->isExpanded(child->index()));
         });
     }
 }
@@ -328,16 +317,15 @@ void TestNavigationWidget::onRunThisTestTriggered(TestRunMode runMode)
 
 void TestNavigationWidget::reapplyCachedExpandedState()
 {
-    for (Utils::TreeItem *rootNode : *m_model->rootItem()) {
-        rootNode->forAllChildren([this](Utils::TreeItem *child) {
-            auto childItem = static_cast<TestTreeItem *>(child);
-            const QString cacheName = childItem->cacheName();
-            const auto it = m_expandedStateCache.find(cacheName);
-            if (it == m_expandedStateCache.end())
-                return;
-            QModelIndex index = child->index();
-            if (m_view->isExpanded(index) != it.value())
-                m_view->setExpanded(index, it.value());
+    using namespace Utils;
+    for (TreeItem *rootNode : *m_model->rootItem()) {
+        rootNode->forAllChildren([this](TreeItem *child) {
+            optional<bool> cached = m_expandedStateCache.get(static_cast<TestTreeItem *>(child));
+            if (cached.has_value()) {
+                QModelIndex index = child->index();
+                if (m_view->isExpanded(index) != cached.value())
+                    m_view->setExpanded(index, cached.value());
+            }
         });
     }
 }
diff --git a/src/plugins/autotest/testnavigationwidget.h b/src/plugins/autotest/testnavigationwidget.h
index 23a12d4254..454f893c6b 100644
--- a/src/plugins/autotest/testnavigationwidget.h
+++ b/src/plugins/autotest/testnavigationwidget.h
@@ -27,6 +27,8 @@
 
 #include "testrunner.h"
 
+#include "testtreemodel.h"
+
 #include <coreplugin/inavigationwidgetfactory.h>
 
 #include <utils/navigationtreeview.h>
@@ -47,12 +49,8 @@ class ProgressIndicator;
 }
 
 namespace Autotest {
-
-class TestTreeModel;
-
 namespace Internal {
 
-class TestTreeSortFilterModel;
 class TestTreeView;
 
 class TestNavigationWidget : public QWidget
@@ -86,8 +84,7 @@ private:
     Utils::ProgressIndicator *m_progressIndicator;
     QTimer *m_progressTimer;
     QFrame *m_missingFrameworksWidget;
-    QHash<QString, bool> m_expandedStateCache;
-    QHash<QString, int> m_itemUseCache;
+    ItemDataCache<bool> m_expandedStateCache;
 };
 
 class TestNavigationWidgetFactory : public Core::INavigationWidgetFactory
diff --git a/src/plugins/autotest/testtreemodel.cpp b/src/plugins/autotest/testtreemodel.cpp
index 13d62216f2..95330d5fc9 100644
--- a/src/plugins/autotest/testtreemodel.cpp
+++ b/src/plugins/autotest/testtreemodel.cpp
@@ -92,7 +92,6 @@ void TestTreeModel::setupParsingConnections()
         synchronizeTestFrameworks(); // we might have project settings
         m_parser->onStartupProjectChanged(project);
         m_checkStateCache.clear(); // TODO persist to project settings?
-        m_itemUseCache.clear();
     });
 
     CppTools::CppModelManager *cppMM = CppTools::CppModelManager::instance();
@@ -295,22 +294,12 @@ void TestTreeModel::rebuild(const QList<Utils::Id> &frameworkIds)
 
 void TestTreeModel::updateCheckStateCache()
 {
-    // raise generation for cached items and drop anything reaching 10th generation
-    const QList<QString> cachedNames = m_itemUseCache.keys();
-    for (const QString &cachedName : cachedNames) {
-        auto it = m_itemUseCache.find(cachedName);
-        if (it.value()++ >= 10) {
-            m_itemUseCache.erase(it);
-            m_checkStateCache.remove(cachedName);
-        }
-    }
+    m_checkStateCache.evolve();
 
     for (Utils::TreeItem *rootNode : *rootItem()) {
         rootNode->forAllChildren([this](Utils::TreeItem *child) {
             auto childItem = static_cast<TestTreeItem *>(child);
-            const QString cacheName = childItem->cacheName();
-            m_checkStateCache.insert(cacheName, childItem->checked());
-            m_itemUseCache[cacheName] = 0; // explicitly mark as 0-generation
+            m_checkStateCache.insert(childItem, childItem->checked());
         });
     }
 }
@@ -436,8 +425,8 @@ void TestTreeModel::insertItemInParent(TestTreeItem *item, TestTreeItem *root, b
         delete item;
     } else {
         // restore former check state if available
-        auto cached = m_checkStateCache.find(item->cacheName());
-        if (cached != m_checkStateCache.end())
+        Utils::optional<Qt::CheckState> cached = m_checkStateCache.get(item);
+        if (cached.has_value())
             item->setData(0, cached.value(), Qt::CheckStateRole);
         else
             applyParentCheckState(parentNode, item);
@@ -526,8 +515,8 @@ void TestTreeModel::handleParseResult(const TestParseResult *result, TestTreeIte
     // restore former check state if available
     newItem->forAllChildren([this](Utils::TreeItem *child) {
         auto childItem = static_cast<TestTreeItem *>(child);
-        auto cached = m_checkStateCache.find(childItem->cacheName());
-        if (cached != m_checkStateCache.end())
+        Utils::optional<Qt::CheckState> cached = m_checkStateCache.get(childItem);
+        if (cached.has_value())
             childItem->setData(0, cached.value(), Qt::CheckStateRole);
     });
     // it might be necessary to "split" created item
diff --git a/src/plugins/autotest/testtreemodel.h b/src/plugins/autotest/testtreemodel.h
index af3501c484..4ca3cb27b4 100644
--- a/src/plugins/autotest/testtreemodel.h
+++ b/src/plugins/autotest/testtreemodel.h
@@ -30,6 +30,7 @@
 #include "testconfiguration.h"
 #include "testtreeitem.h"
 
+#include <utils/algorithm.h>
 #include <utils/treemodel.h>
 
 #include <QSortFilterProxyModel>
@@ -38,6 +39,40 @@ namespace Autotest {
 namespace Internal {
 class AutotestPluginPrivate;
 class TestCodeParser;
+
+template<class T>
+class ItemDataCache
+{
+public:
+    void insert(TestTreeItem *item, const T &value) { m_cache[item->cacheName()] = {0, value}; }
+    void evolve()
+    {
+        auto it = m_cache.begin(), end = m_cache.end();
+        while (it != end)
+            it = it->generation++ >= maxGen ? m_cache.erase(it) : ++it;
+    }
+
+    Utils::optional<T> get(TestTreeItem *item)
+    {
+        auto entry = m_cache.find(item->cacheName());
+        if (entry == m_cache.end())
+            return Utils::nullopt;
+        entry->generation = 0;
+        return Utils::make_optional(entry->value);
+    };
+
+    void clear() { m_cache.clear(); }
+
+private:
+    static constexpr int maxGen = 10;
+    struct Entry
+    {
+        int generation = 0;
+        T value;
+    };
+    QHash<QString, Entry> m_cache;
+};
+
 } // namespace Internal
 
 class TestParseResult;
@@ -104,8 +139,7 @@ private:
     QList<TestTreeItem *> testItemsByName(TestTreeItem *root, const QString &testName);
 
     Internal::TestCodeParser *m_parser = nullptr;
-    QHash<QString, Qt::CheckState> m_checkStateCache;
-    QHash<QString, int> m_itemUseCache;
+    Internal::ItemDataCache<Qt::CheckState> m_checkStateCache;
 };
 
 namespace Internal {