CppTools: Rework handling of ProjectInfo changes

(a) The code model manager figures out by itself which files were added
    or removed from the project.

    If this was done successfully, check also the timestamp of the
    common files and reindex if necessary.

(b) A full reindexing is only triggered if the project configuration
    changes (defines, includes, framework paths).

(c) If project files were removed, the garbage collector is called.

Task-number: QTCREATORBUG-9730
Change-Id: Ib855614b070880576233a3525813617c967a72f3
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>

6 files changed, 415 insertions, 32 deletions

diff --git a/src/plugins/cpptools/cppmodelmanager.cpp b/src/plugins/cpptools/cppmodelmanager.cpp
index d9f53f2f5d..b22c42fdaa 100644
--- a/src/plugins/cpptools/cppmodelmanager.cpp
+++ b/src/plugins/cpptools/cppmodelmanager.cpp
@@ -172,12 +172,11 @@ static const char pp_configuration[] =
     "#define __inline inline\n"
     "#define __forceinline inline\n";
 
-void CppModelManager::updateModifiedSourceFiles()
+QStringList CppModelManager::timeStampModifiedFiles(const QList<Document::Ptr> documentsToCheck)
 {
-    const Snapshot snapshot = this->snapshot();
     QStringList sourceFiles;
 
-    foreach (const Document::Ptr doc, snapshot) {
+    foreach (const Document::Ptr doc, documentsToCheck) {
         const QDateTime lastModified = doc->lastModified();
 
         if (!lastModified.isNull()) {
@@ -188,7 +187,18 @@ void CppModelManager::updateModifiedSourceFiles()
         }
     }
 
-    updateSourceFiles(sourceFiles);
+    return sourceFiles;
+}
+
+void CppModelManager::updateModifiedSourceFiles()
+{
+    const Snapshot snapshot = this->snapshot();
+    QList<Document::Ptr> documentsToCheck;
+    foreach (const Document::Ptr document, snapshot)
+        documentsToCheck << document;
+
+    const QStringList filesToUpdate = timeStampModifiedFiles(documentsToCheck);
+    updateSourceFiles(filesToUpdate);
 }
 
 /*!
@@ -584,39 +594,155 @@ CppModelManager::ProjectInfo CppModelManager::projectInfo(ProjectExplorer::Proje
     return m_projectToProjectsInfo.value(project, ProjectInfo(project));
 }
 
-QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &pinfo)
+/// \brief Remove all files and their includes (recursively) of given ProjectInfo from the snapshot.
+void CppModelManager::removeProjectInfoFilesAndIncludesFromSnapshot(const ProjectInfo &projectInfo)
+{
+    if (!projectInfo.isValid())
+        return;
+
+    QMutexLocker snapshotLocker(&m_snapshotMutex);
+    foreach (const ProjectPart::Ptr &projectPart, projectInfo.projectParts()) {
+        foreach (const ProjectFile &cxxFile, projectPart->files) {
+            foreach (const QString &fileName, m_snapshot.allIncludesForDocument(cxxFile.path))
+                m_snapshot.remove(fileName);
+            m_snapshot.remove(cxxFile.path);
+        }
+    }
+}
+
+/// \brief Remove all given files from the snapshot.
+void CppModelManager::removeFilesFromSnapshot(const QSet<QString> &filesToRemove)
+{
+    QMutexLocker snapshotLocker(&m_snapshotMutex);
+    QSetIterator<QString> i(filesToRemove);
+    while (i.hasNext())
+        m_snapshot.remove(i.next());
+}
+
+class ProjectInfoComparer
+{
+public:
+    ProjectInfoComparer(const CppModelManager::ProjectInfo &oldProjectInfo,
+                        const CppModelManager::ProjectInfo &newProjectInfo)
+        : m_old(oldProjectInfo)
+        , m_oldSourceFiles(oldProjectInfo.sourceFiles().toSet())
+        , m_new(newProjectInfo)
+        , m_newSourceFiles(newProjectInfo.sourceFiles().toSet())
+    {}
+
+    bool definesChanged() const
+    {
+        return m_new.defines() != m_old.defines();
+    }
+
+    bool configurationChanged() const
+    {
+        return definesChanged()
+            || m_new.includePaths() != m_old.includePaths()
+            || m_new.frameworkPaths() != m_old.frameworkPaths();
+    }
+
+    bool nothingChanged() const
+    {
+        return !configurationChanged() && m_new.sourceFiles() == m_old.sourceFiles();
+    }
+
+    QSet<QString> addedFiles() const
+    {
+        QSet<QString> addedFilesSet = m_newSourceFiles;
+        addedFilesSet.subtract(m_oldSourceFiles);
+        return addedFilesSet;
+    }
+
+    QSet<QString> removedFiles() const
+    {
+        QSet<QString> removedFilesSet = m_oldSourceFiles;
+        removedFilesSet.subtract(m_newSourceFiles);
+        return removedFilesSet;
+    }
+
+    /// Returns a list of common files that have a changed timestamp.
+    QSet<QString> timeStampModifiedFiles(const Snapshot &snapshot) const
+    {
+        QSet<QString> commonSourceFiles = m_newSourceFiles;
+        commonSourceFiles.intersect(m_oldSourceFiles);
+
+        QList<Document::Ptr> documentsToCheck;
+        QSetIterator<QString> i(commonSourceFiles);
+        while (i.hasNext()) {
+            const QString file = i.next();
+            if (Document::Ptr document = snapshot.document(file))
+                documentsToCheck << document;
+        }
+
+        return CppModelManager::timeStampModifiedFiles(documentsToCheck).toSet();
+    }
+
+private:
+    const CppModelManager::ProjectInfo &m_old;
+    const QSet<QString> m_oldSourceFiles;
+
+    const CppModelManager::ProjectInfo &m_new;
+    const QSet<QString> m_newSourceFiles;
+};
+
+QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &newProjectInfo)
 {
-    if (!pinfo.isValid())
+    if (!newProjectInfo.isValid())
         return QFuture<void>();
 
+    QStringList filesToReindex;
+    bool filesRemoved = false;
+
     { // Only hold the mutex for a limited scope, so the dumping afterwards does not deadlock.
-        QMutexLocker locker(&m_projectMutex);
+        QMutexLocker projectLocker(&m_projectMutex);
 
-        ProjectExplorer::Project *project = pinfo.project().data();
+        ProjectExplorer::Project *project = newProjectInfo.project().data();
+        const QStringList newSourceFiles = newProjectInfo.sourceFiles();
+
+        // Check if we can avoid a full reindexing
         ProjectInfo oldProjectInfo = m_projectToProjectsInfo.value(project);
         if (oldProjectInfo.isValid()) {
-            if (pinfo.defines() == oldProjectInfo.defines()
-                    && pinfo.includePaths() == oldProjectInfo.includePaths()
-                    && pinfo.frameworkPaths() == oldProjectInfo.frameworkPaths()
-                    && pinfo.sourceFiles() == oldProjectInfo.sourceFiles()) {
+            ProjectInfoComparer comparer(oldProjectInfo, newProjectInfo);
+            if (comparer.nothingChanged())
                 return QFuture<void>();
-            }
 
-            foreach (const ProjectPart::Ptr &projectPart, oldProjectInfo.projectParts()) {
-                foreach (const ProjectFile &cxxFile, projectPart->files) {
-                    foreach (const QString &fileName,
-                             m_snapshot.allIncludesForDocument(cxxFile.path)) {
-                        m_snapshot.remove(fileName);
-                    }
-                    m_snapshot.remove(cxxFile.path);
+            // If the project configuration changed, do a full reindexing
+            if (comparer.configurationChanged()) {
+                removeProjectInfoFilesAndIncludesFromSnapshot(oldProjectInfo);
+                filesToReindex << newSourceFiles;
+
+                // The "configuration file" includes all defines and therefore should be updated
+                if (comparer.definesChanged()) {
+                    QMutexLocker snapshotLocker(&m_snapshotMutex);
+                    m_snapshot.remove(configurationFileName());
                 }
+
+            // Otherwise check for added and modified files
+            } else {
+                const QSet<QString> addedFiles = comparer.addedFiles();
+                filesToReindex << addedFiles.toList();
+
+                const QSet<QString> modifiedFiles = comparer.timeStampModifiedFiles(snapshot());
+                filesToReindex << modifiedFiles.toList();
             }
+
+            // Announce and purge the removed files from the snapshot
+            const QSet<QString> removedFiles = comparer.removedFiles();
+            if (!removedFiles.isEmpty()) {
+                filesRemoved = true;
+                emit aboutToRemoveFiles(removedFiles.toList());
+                removeFilesFromSnapshot(removedFiles);
+            }
+
+        // A new project was opened/created, do a full indexing
+        } else {
+            filesToReindex << newSourceFiles;
         }
-        m_snapshot.remove(configurationFileName());
 
-        m_projectToProjectsInfo.insert(project, pinfo);
+        // Update Project/ProjectInfo and File/ProjectPart table
         m_dirty = true;
-
+        m_projectToProjectsInfo.insert(project, newProjectInfo);
         m_fileToProjectParts.clear();
         foreach (const ProjectInfo &projectInfo, m_projectToProjectsInfo) {
             foreach (const ProjectPart::Ptr &projectPart, projectInfo.projectParts()) {
@@ -625,14 +751,21 @@ QFuture<void> CppModelManager::updateProjectInfo(const ProjectInfo &pinfo)
                 }
             }
         }
-    }
 
+    } // Mutex scope
+
+    // If requested, dump everything we got
     if (!qgetenv("QTCREATOR_DUMP_PROJECT_INFO").isEmpty())
         dumpModelManagerConfiguration();
 
-    emit projectPartsUpdated(pinfo.project().data());
+    // Remove files from snapshot that are not reachable any more
+    if (filesRemoved)
+        GC();
+
+    emit projectPartsUpdated(newProjectInfo.project().data());
 
-    return updateSourceFiles(pinfo.sourceFiles(), ForcedProgressNotification);
+    // Trigger reindexing
+    return updateSourceFiles(filesToReindex, ForcedProgressNotification);
 }
 
 QList<ProjectPart::Ptr> CppModelManager::projectPart(const QString &fileName) const
diff --git a/src/plugins/cpptools/cppmodelmanager.h b/src/plugins/cpptools/cppmodelmanager.h
index 5c65a9781a..249cfb65ac 100644
--- a/src/plugins/cpptools/cppmodelmanager.h
+++ b/src/plugins/cpptools/cppmodelmanager.h
@@ -72,7 +72,7 @@ public:
 
     virtual QList<ProjectInfo> projectInfos() const;
     virtual ProjectInfo projectInfo(ProjectExplorer::Project *project) const;
-    virtual QFuture<void> updateProjectInfo(const ProjectInfo &pinfo);
+    virtual QFuture<void> updateProjectInfo(const ProjectInfo &newProjectInfo);
     virtual QList<CppTools::ProjectPart::Ptr> projectPart(const QString &fileName) const;
 
     virtual CPlusPlus::Snapshot snapshot() const;
@@ -141,6 +141,8 @@ public:
         return m_definedMacros;
     }
 
+    static QStringList timeStampModifiedFiles(const QList<Document::Ptr> documentsToCheck);
+
 signals:
     void aboutToRemoveFiles(const QStringList &files);
     void gcFinished(); // Needed for tests.
@@ -160,6 +162,9 @@ private slots:
 private:
     void delayedGC();
     void replaceSnapshot(const CPlusPlus::Snapshot &newSnapshot);
+    void removeFilesFromSnapshot(const QSet<QString> &removedFiles);
+    void removeProjectInfoFilesAndIncludesFromSnapshot(const ProjectInfo &projectInfo);
+
     WorkingCopy buildWorkingCopyList();
 
     void ensureUpdated();
diff --git a/src/plugins/cpptools/cppmodelmanager_test.cpp b/src/plugins/cpptools/cppmodelmanager_test.cpp
index 1fb02ba5ed..34c05f0ac7 100644
--- a/src/plugins/cpptools/cppmodelmanager_test.cpp
+++ b/src/plugins/cpptools/cppmodelmanager_test.cpp
@@ -48,6 +48,8 @@ typedef CppTools::ProjectPart ProjectPart;
 typedef CppTools::ProjectFile ProjectFile;
 typedef ProjectExplorer::Project Project;
 
+Q_DECLARE_METATYPE(ProjectFile)
+
 namespace {
 
 class TestDataDirectory
@@ -176,6 +178,52 @@ private:
     QString m_fileToRemove;
 };
 
+/// Changes a file on the disk and restores its original contents on destruction
+class FileChangerAndRestorer
+{
+public:
+    FileChangerAndRestorer(const QString &filePath)
+        : m_filePath(filePath)
+    {
+    }
+
+    ~FileChangerAndRestorer()
+    {
+        restoreContents();
+    }
+
+    /// Saves the contents also internally so it can be restored on destruction
+    bool readContents(QByteArray *contents)
+    {
+        Utils::FileReader fileReader;
+        const bool isFetchOk = fileReader.fetch(m_filePath);
+        if (isFetchOk) {
+            m_originalFileContents = fileReader.data();
+            if (contents)
+                *contents = m_originalFileContents;
+        }
+        return isFetchOk;
+    }
+
+    void writeContents(const QByteArray &contents) const
+    {
+        Utils::FileSaver fileSaver(m_filePath);
+        fileSaver.write(contents);
+        fileSaver.finalize();
+    }
+
+private:
+    void restoreContents() const
+    {
+        Utils::FileSaver fileSaver(m_filePath);
+        fileSaver.write(m_originalFileContents);
+        fileSaver.finalize();
+    }
+
+    QByteArray m_originalFileContents;
+    const QString &m_filePath;
+};
+
 } // anonymous namespace
 
 /// Check: The preprocessor cleans include and framework paths.
@@ -232,8 +280,7 @@ void CppToolsPlugin::test_modelmanager_framework_headers()
     part->files << ProjectFile(source, ProjectFile::CXXSource);
     pi.appendProjectPart(part);
 
-    mm->updateProjectInfo(pi);
-    mm->updateSourceFiles(QStringList(source)).waitForFinished();
+    mm->updateProjectInfo(pi).waitForFinished();
     QCoreApplication::processEvents();
 
     QVERIFY(mm->snapshot().contains(source));
@@ -280,7 +327,6 @@ void CppToolsPlugin::test_modelmanager_refresh_also_includes_of_project_files()
     part->includePaths = QStringList() << testDataDir.includeDir(false);
     part->files.append(ProjectFile(testCpp, ProjectFile::CXXSource));
     pi.appendProjectPart(part);
-
     mm->updateProjectInfo(pi);
 
     QStringList refreshedFiles = helper.waitForRefreshedSourceFiles();
@@ -301,6 +347,7 @@ void CppToolsPlugin::test_modelmanager_refresh_also_includes_of_project_files()
     pi.clearProjectParts();
     pi.appendProjectPart(part);
     mm->updateProjectInfo(pi);
+
     refreshedFiles = helper.waitForRefreshedSourceFiles();
 
     QCOMPARE(refreshedFiles.size(), 1);
@@ -342,7 +389,6 @@ void CppToolsPlugin::test_modelmanager_refresh_several_times()
     part->files.append(ProjectFile(testHeader2, ProjectFile::CXXHeader));
     part->files.append(ProjectFile(testCpp, ProjectFile::CXXSource));
     pi.appendProjectPart(part);
-
     mm->updateProjectInfo(pi);
 
     CPlusPlus::Snapshot snapshot;
@@ -364,6 +410,7 @@ void CppToolsPlugin::test_modelmanager_refresh_several_times()
         pi.appendProjectPart(part);
 
         mm->updateProjectInfo(pi);
+
         refreshedFiles = helper.waitForRefreshedSourceFiles();
 
         QCOMPARE(refreshedFiles.size(), 3);
@@ -420,6 +467,165 @@ void CppToolsPlugin::test_modelmanager_refresh_test_for_changes()
     QVERIFY(subsequentFuture.isCanceled() && subsequentFuture.isFinished());
 }
 
+/// Check: (1) Added project files are recognized and parsed.
+/// Check: (2) Removed project files are recognized and purged from the snapshot.
+void CppToolsPlugin::test_modelmanager_refresh_added_and_purge_removed()
+{
+    ModelManagerTestHelper helper;
+    CppModelManager *mm = CppModelManager::instance();
+
+    const TestDataDirectory testDataDir(QLatin1String("testdata_refresh"));
+
+    const QString testHeader1(testDataDir.file(QLatin1String("header.h")));
+    const QString testHeader2(testDataDir.file(QLatin1String("defines.h")));
+    const QString testCpp(testDataDir.file(QLatin1String("source.cpp")));
+
+    Project *project = helper.createProject(QLatin1String("test_modelmanager_refresh_3"));
+    ProjectInfo pi = mm->projectInfo(project);
+    QCOMPARE(pi.project().data(), project);
+
+    ProjectPart::Ptr part(new ProjectPart);
+    part->cxxVersion = ProjectPart::CXX98;
+    part->qtVersion = ProjectPart::Qt5;
+    part->files.append(ProjectFile(testCpp, ProjectFile::CXXSource));
+    part->files.append(ProjectFile(testHeader1, ProjectFile::CXXHeader));
+    pi.appendProjectPart(part);
+
+    CPlusPlus::Snapshot snapshot;
+    QStringList refreshedFiles;
+
+    mm->updateProjectInfo(pi);
+    refreshedFiles = helper.waitForRefreshedSourceFiles();
+
+    QCOMPARE(refreshedFiles.size(), 2);
+    QVERIFY(refreshedFiles.contains(testHeader1));
+    QVERIFY(refreshedFiles.contains(testCpp));
+
+    snapshot = mm->snapshot();
+    QVERIFY(snapshot.contains(testHeader1));
+    QVERIFY(snapshot.contains(testCpp));
+
+    // Now add testHeader2 and remove testHeader1
+    pi.clearProjectParts();
+    ProjectPart::Ptr newPart(new ProjectPart);
+    newPart->cxxVersion = ProjectPart::CXX98;
+    newPart->qtVersion = ProjectPart::Qt5;
+    newPart->files.append(ProjectFile(testCpp, ProjectFile::CXXSource));
+    newPart->files.append(ProjectFile(testHeader2, ProjectFile::CXXHeader));
+    pi.appendProjectPart(newPart);
+
+    mm->updateProjectInfo(pi);
+    refreshedFiles = helper.waitForRefreshedSourceFiles();
+
+    // Only the added project file was reparsed
+    QCOMPARE(refreshedFiles.size(), 1);
+    QVERIFY(refreshedFiles.contains(testHeader2));
+
+    snapshot = mm->snapshot();
+    QVERIFY(snapshot.contains(testHeader2));
+    QVERIFY(snapshot.contains(testCpp));
+    // The removed project file is not anymore in the snapshot
+    QVERIFY(!snapshot.contains(testHeader1));
+}
+
+/// Check: Timestamp modified files are reparsed if project files are added or removed
+///        while the project configuration stays the same
+void CppToolsPlugin::test_modelmanager_refresh_timeStampModified_if_sourcefiles_change()
+{
+    QFETCH(QString, fileToChange);
+    QFETCH(QList<ProjectFile>, initialProjectFiles);
+    QFETCH(QList<ProjectFile>, finalProjectFiles);
+
+    ModelManagerTestHelper helper;
+    CppModelManager *mm = CppModelManager::instance();
+
+    Project *project = helper.createProject(
+        QLatin1String("test_modelmanager_refresh_timeStampModified"));
+    ProjectInfo pi = mm->projectInfo(project);
+    QCOMPARE(pi.project().data(), project);
+
+    ProjectPart::Ptr part(new ProjectPart);
+    part->cxxVersion = ProjectPart::CXX98;
+    part->qtVersion = ProjectPart::Qt5;
+    foreach (const ProjectFile &file, initialProjectFiles)
+        part->files.append(file);
+    pi.appendProjectPart(part);
+
+    Document::Ptr document;
+    CPlusPlus::Snapshot snapshot;
+    QStringList refreshedFiles;
+
+    mm->updateProjectInfo(pi);
+    refreshedFiles = helper.waitForRefreshedSourceFiles();
+
+    QCOMPARE(refreshedFiles.size(), initialProjectFiles.size());
+    snapshot = mm->snapshot();
+    foreach (const ProjectFile &file, initialProjectFiles) {
+        QVERIFY(refreshedFiles.contains(file.path));
+        QVERIFY(snapshot.contains(file.path));
+    }
+
+    document = snapshot.document(fileToChange);
+    const QDateTime lastModifiedBefore = document->lastModified();
+    QCOMPARE(document->globalSymbolCount(), 1U);
+    QCOMPARE(document->globalSymbolAt(0)->name()->identifier()->chars(), "someGlobal");
+
+    // Modify the file
+    QTest::qSleep(1000); // Make sure the timestamp is different
+    FileChangerAndRestorer fileChangerAndRestorer(fileToChange);
+    QByteArray originalContents;
+    QVERIFY(fileChangerAndRestorer.readContents(&originalContents));
+    const QByteArray newFileContentes = originalContents + "\nint addedOtherGlobal;";
+    fileChangerAndRestorer.writeContents(newFileContentes);
+
+    // Add or remove source file. The configuration stays the same.
+    part->files.clear();
+    foreach (const ProjectFile &file, finalProjectFiles)
+        part->files.append(file);
+    pi.clearProjectParts();
+    pi.appendProjectPart(part);
+
+    mm->updateProjectInfo(pi);
+    refreshedFiles = helper.waitForRefreshedSourceFiles();
+
+    QCOMPARE(refreshedFiles.size(), finalProjectFiles.size());
+    snapshot = mm->snapshot();
+    foreach (const ProjectFile &file, finalProjectFiles) {
+        QVERIFY(refreshedFiles.contains(file.path));
+        QVERIFY(snapshot.contains(file.path));
+    }
+    document = snapshot.document(fileToChange);
+    const QDateTime lastModifiedAfter = document->lastModified();
+    QVERIFY(lastModifiedAfter > lastModifiedBefore);
+    QCOMPARE(document->globalSymbolCount(), 2U);
+    QCOMPARE(document->globalSymbolAt(0)->name()->identifier()->chars(), "someGlobal");
+    QCOMPARE(document->globalSymbolAt(1)->name()->identifier()->chars(), "addedOtherGlobal");
+}
+
+void CppToolsPlugin::test_modelmanager_refresh_timeStampModified_if_sourcefiles_change_data()
+{
+    QTest::addColumn<QString>("fileToChange");
+    QTest::addColumn<QList<ProjectFile> >("initialProjectFiles");
+    QTest::addColumn<QList<ProjectFile> >("finalProjectFiles");
+
+    const TestDataDirectory testDataDir(QLatin1String("testdata_refresh2"));
+    const QString testCpp(testDataDir.file(QLatin1String("source.cpp")));
+    const QString testCpp2(testDataDir.file(QLatin1String("source2.cpp")));
+
+    const QString fileToChange = testCpp;
+    QList<ProjectFile> projectFiles1 = QList<ProjectFile>()
+        << ProjectFile(testCpp, ProjectFile::CXXSource);
+    QList<ProjectFile> projectFiles2 = QList<ProjectFile>()
+        << ProjectFile(testCpp, ProjectFile::CXXSource)
+        << ProjectFile(testCpp2, ProjectFile::CXXSource);
+
+    // Add a file
+    QTest::newRow("case: add project file") << fileToChange << projectFiles1 << projectFiles2;
+
+    // Remove a file
+    QTest::newRow("case: remove project file") << fileToChange << projectFiles2 << projectFiles1;
+}
+
 /// Check: If a second project is opened, the code model is still aware of
 ///        files of the first project.
 void CppToolsPlugin::test_modelmanager_snapshot_after_two_projects()
diff --git a/src/plugins/cpptools/cppmodelmanagerinterface.cpp b/src/plugins/cpptools/cppmodelmanagerinterface.cpp
index 1338c214a1..cb5ba96e6d 100644
--- a/src/plugins/cpptools/cppmodelmanagerinterface.cpp
+++ b/src/plugins/cpptools/cppmodelmanagerinterface.cpp
@@ -68,6 +68,37 @@ using namespace ProjectExplorer;
            Parser may enable tricks for Qt v5.x
 */
 
+/*!
+    \fn virtual QFuture<void> updateProjectInfo(const ProjectInfo &pinfo) = 0;
+    \param pinfo Updated ProjectInfo.
+    \return A future that reports progress and allows to cancel the reparsing operation.
+
+    This function is expected to be called by the project managers to update the
+    code model with new project information.
+
+    In particular, the function should be called in case:
+        1. A new project is opened/created
+        2. The project configuration changed. This includes
+             2.1 Changes of defines, includes, framework paths
+             2.2 Addition/Removal of project files
+
+    \sa CppTools::CppModelManagerInterface::updateSourceFiles()
+*/
+
+/*!
+    \fn virtual QFuture<void> updateSourceFiles(const QStringList &sourceFiles, ProgressNotificationMode mode = ReservedProgressNotification) = 0;
+    \param sourceFiles List of source file to update. The items are absolute paths.
+    \param mode The progress modification mode.
+    \return A future that reports progress and allows to cancel the reparsing operation.
+
+    Trigger an asynchronous reparsing of the given source files.
+
+    This function is not meant to be called by the project managers.
+
+    \sa CppTools::CppModelManagerInterface::ProgressNotificationMode
+    \sa CppTools::CppModelManagerInterface::updateProjectInfo()
+*/
+
 ProjectPart::ProjectPart()
     : cVersion(C89)
     , cxxVersion(CXX11)
diff --git a/src/plugins/cpptools/cppmodelmanagerinterface.h b/src/plugins/cpptools/cppmodelmanagerinterface.h
index e4885ea578..d61020337e 100644
--- a/src/plugins/cpptools/cppmodelmanagerinterface.h
+++ b/src/plugins/cpptools/cppmodelmanagerinterface.h
@@ -249,6 +249,9 @@ public:
     virtual CppTools::CppIndexingSupport *indexingSupport() = 0;
 
 signals:
+    /// Project data might be locked while this is emitted.
+    void aboutToRemoveFiles(const QStringList &files);
+
     void documentUpdated(CPlusPlus::Document::Ptr doc);
     void sourceFilesRefreshed(const QStringList &files);
 
@@ -258,9 +261,11 @@ signals:
     void projectPartsUpdated(ProjectExplorer::Project *project);
 
 public slots:
-    virtual void updateModifiedSourceFiles() = 0;
+    // Documented in source file.
     virtual QFuture<void> updateSourceFiles(const QStringList &sourceFiles,
         ProgressNotificationMode mode = ReservedProgressNotification) = 0;
+
+    virtual void updateModifiedSourceFiles() = 0;
     virtual void GC() = 0;
 };
 
diff --git a/src/plugins/cpptools/cpptoolsplugin.h b/src/plugins/cpptools/cpptoolsplugin.h
index de48a8fe21..70d9dfb685 100644
--- a/src/plugins/cpptools/cpptoolsplugin.h
+++ b/src/plugins/cpptools/cpptoolsplugin.h
@@ -192,6 +192,9 @@ private slots:
     void test_modelmanager_refresh_also_includes_of_project_files();
     void test_modelmanager_refresh_several_times();
     void test_modelmanager_refresh_test_for_changes();
+    void test_modelmanager_refresh_added_and_purge_removed();
+    void test_modelmanager_refresh_timeStampModified_if_sourcefiles_change();
+    void test_modelmanager_refresh_timeStampModified_if_sourcefiles_change_data();
     void test_modelmanager_snapshot_after_two_projects();
     void test_modelmanager_extraeditorsupport_uiFiles();
     void test_modelmanager_gc_if_last_cppeditor_closed();