CppTools: Do not call GC() more than necessary

Currently GC() is invoked if
   - 5 CppEditors were closed or the last CppEditor was closed
   - a project is about to be removed
   - a session is about to be unloaded

Thus, for the following use cases, too much GC() calls (can) happen:
    - File > Close All
    - Close All Projects and Editors
    - Changing the session

Fixed by introducing a timer.

Change-Id: I9c984d9de735fc8c6ee77a518e9fb5b63dba5881
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

1 files changed, 21 insertions, 3 deletions

diff --git a/src/plugins/cpptools/cppmodelmanager.cpp b/src/plugins/cpptools/cppmodelmanager.cpp
index ed1ebd1479..cc1979d6b7 100644
--- a/src/plugins/cpptools/cppmodelmanager.cpp
+++ b/src/plugins/cpptools/cppmodelmanager.cpp
@@ -233,6 +233,10 @@ CppModelManager::CppModelManager(QObject *parent)
     ProjectExplorer::ProjectExplorerPlugin *pe = ProjectExplorer::ProjectExplorerPlugin::instance();
     QTC_ASSERT(pe, return);
 
+    m_delayedGcTimer = new QTimer(this);
+    m_delayedGcTimer->setSingleShot(true);
+    connect(m_delayedGcTimer, SIGNAL(timeout()), this, SLOT(GC()));
+
     ProjectExplorer::SessionManager *session = pe->session();
     connect(session, SIGNAL(projectAdded(ProjectExplorer::Project*)),
             this, SLOT(onProjectAdded(ProjectExplorer::Project*)));
@@ -240,6 +244,9 @@ CppModelManager::CppModelManager(QObject *parent)
     connect(session, SIGNAL(aboutToRemoveProject(ProjectExplorer::Project*)),
             this, SLOT(onAboutToRemoveProject(ProjectExplorer::Project*)));
 
+    connect(session, SIGNAL(aboutToLoadSession(QString)),
+            this, SLOT(onAboutToLoadSession()));
+
     connect(session, SIGNAL(aboutToUnloadSession(QString)),
             this, SLOT(onAboutToUnloadSession()));
 
@@ -481,7 +488,7 @@ void CppModelManager::deleteCppEditorSupport(TextEditor::BaseTextEditor *textEdi
     ++numberOfClosedEditors;
     if (numberOfOpenEditors == 0 || numberOfClosedEditors == 5) {
         numberOfClosedEditors = 0;
-        GC();
+        delayedGC();
     }
 }
 
@@ -663,6 +670,11 @@ void CppModelManager::onProjectAdded(ProjectExplorer::Project *)
     m_dirty = true;
 }
 
+void CppModelManager::delayedGC()
+{
+    m_delayedGcTimer->start(500);
+}
+
 void CppModelManager::onAboutToRemoveProject(ProjectExplorer::Project *project)
 {
     do {
@@ -671,6 +683,13 @@ void CppModelManager::onAboutToRemoveProject(ProjectExplorer::Project *project)
         m_projectToProjectsInfo.remove(project);
     } while (0);
 
+    delayedGC();
+}
+
+void CppModelManager::onAboutToLoadSession()
+{
+    if (m_delayedGcTimer->isActive())
+        m_delayedGcTimer->stop();
     GC();
 }
 
@@ -683,8 +702,6 @@ void CppModelManager::onAboutToUnloadSession()
         m_projectToProjectsInfo.clear();
         m_dirty = true;
     } while (0);
-
-    GC();
 }
 
 void CppModelManager::onCoreAboutToClose()
@@ -729,6 +746,7 @@ void CppModelManager::GC()
     // Announce removing files and replace the snapshot
     emit aboutToRemoveFiles(notReachableFiles);
     replaceSnapshot(newSnapshot);
+    emit gcFinished();
 }
 
 void CppModelManager::finishedRefreshingSourceFiles(const QStringList &files)