Vcs: Hide topic cache in new IVersionControl pimpl

Potentially more stable api long-term. Also simplifies the
user side code a bit.

Change-Id: I6913e27e2a5dc14907e72f252081cdbed34842a3
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>

src/plugins/coreplugin/iversioncontrol.cpp

@@ -14,44 +14,40 @@
 #include <QRegularExpression>
 #include <QStringList>
 
-/*!
-    \class Core::IVersionControl::TopicCache
-    \inheaderfile coreplugin/iversioncontrol.h
-    \inmodule QtCreator
-
-    \brief The TopicCache class stores a cache which maps a directory to a topic.
-
-    A VCS topic is typically the current active branch name, but it can also have other
-    values (for example the latest tag) when there is no active branch.
-
-    It is displayed:
-    \list
-    \li In the project tree, next to each root project - corresponding to the project.
-    \li In the main window title - corresponding to the current active editor.
-    \endlist
-
-    In order to enable topic display, an IVersionControl subclass needs to create
-    an instance of the TopicCache subclass with appropriate overrides for its
-    pure virtual functions, and pass this instance to IVersionControl's constructor.
-
-    The cache tracks a file in the repository, which is expected to change when the
-    topic changes. When the file is modified, the cache is refreshed.
-    For example: for Git this file is typically <repository>/.git/HEAD
- */
-
-/*!
-    \fn Utils::FilePath Core::IVersionControl::TopicCache::trackFile(const Utils::FilePath &repository)
-    Returns the path to the file that invalidates the cache for \a repository when
-    the file is modified.
-
-    \fn QString Core::IVersionControl::TopicCache::refreshTopic(const Utils::FilePath &repository)
-    Returns the current topic for \a repository.
- */
-
 using namespace Utils;
 
 namespace Core {
 
+namespace Internal {
+
+class TopicData
+{
+public:
+    QDateTime timeStamp;
+    QString topic;
+};
+
+class IVersionControlPrivate
+{
+public:
+    IVersionControl::FileTracker m_fileTracker;
+    IVersionControl::TopicRefresher m_topicRefresher;
+    QHash<FilePath, TopicData> m_topicCache;
+};
+
+} // Internal
+
+IVersionControl::IVersionControl()
+    : d(new Internal::IVersionControlPrivate)
+{
+    Core::VcsManager::addVersionControl(this);
+}
+
+IVersionControl::~IVersionControl()
+{
+    delete d;
+}
+
 QString IVersionControl::vcsOpenText() const
 {
     return Tr::tr("Open with VCS (%1)").arg(displayName());
@@ -111,24 +107,83 @@ IVersionControl::RepoUrl IVersionControl::getRepoUrl(const QString &location) co
     return RepoUrl(location);
 }
 
-void IVersionControl::setTopicCache(TopicCache *topicCache)
+FilePath IVersionControl::trackFile(const FilePath &repository)
 {
-    m_topicCache = topicCache;
+    QTC_ASSERT(d->m_fileTracker, return {});
+    return d->m_fileTracker(repository);
 }
 
+QString IVersionControl::refreshTopic(const FilePath &repository)
+{
+    QTC_ASSERT(d->m_topicRefresher, return {});
+    return d->m_topicRefresher(repository);
+}
+
+/*!
+    Returns the topic for repository under \a topLevel.
+
+    A VCS topic is typically the current active branch name, but it can also have other
+    values (for example the latest tag) when there is no active branch.
+
+    It is displayed:
+    \list
+    \li In the project tree, next to each root project - corresponding to the project.
+    \li In the main window title - corresponding to the current active editor.
+    \endlist
+
+    In order to enable topic display, an IVersionControl subclass needs to create
+    an instance of the TopicCache subclass with appropriate overrides for its
+    pure virtual functions, and pass this instance to IVersionControl's constructor.
+
+    The cache tracks a file in the repository, which is expected to change when the
+    topic changes. When the file is modified, the cache is refreshed.
+    For example: for Git this file is typically <repository>/.git/HEAD
+
+    The base implementation features a cache. If the cache for \a topLevel is valid,
+    it will be used. Otherwise it will be refreshed using the items provided by
+    \c setTopicFileTracker() and \c setTopicRefresher().
+
+    \sa setTopicFileTracker(), setTopicRefresher().
+ */
+
 QString IVersionControl::vcsTopic(const FilePath &topLevel)
 {
-    return m_topicCache ? m_topicCache->topic(topLevel) : QString();
+    QTC_ASSERT(!topLevel.isEmpty(), return QString());
+    Internal::TopicData &data = d->m_topicCache[topLevel];
+    const FilePath file = trackFile(topLevel);
+
+    if (file.isEmpty())
+        return QString();
+    const QDateTime lastModified = file.lastModified();
+    if (lastModified == data.timeStamp)
+        return data.topic;
+    data.timeStamp = lastModified;
+    return data.topic = refreshTopic(topLevel);
 }
 
-IVersionControl::IVersionControl()
+/*!
+    Provides the \a fileTracker function object for use in \c vscTopic() cache handling.
+
+    The parameter object takes a repository as input and returns the file
+    that should trigger topic refresh (e.g. .git/HEAD for Git).
+
+    Modification of this file will invalidate the internal topic cache for the repository.
+*/
+
+void IVersionControl::setTopicFileTracker(const FileTracker &fileTracker)
 {
-    Core::VcsManager::addVersionControl(this);
+    d->m_fileTracker = fileTracker;
 }
 
-IVersionControl::~IVersionControl()
+/*!
+    Provides the \a topicRefresher function object for use in \c vscTopic() cache handling.
+
+    The parameter object takes a repository as input and returns its current topic.
+ */
+
+void IVersionControl::setTopicRefresher(const TopicRefresher &topicRefresher)
 {
-    delete m_topicCache;
+    d->m_topicRefresher = topicRefresher;
 }
 
 FilePaths IVersionControl::unmanagedFiles(const FilePaths &filePaths) const
@@ -143,29 +198,6 @@ IVersionControl::OpenSupportMode IVersionControl::openSupportMode(const FilePath
     Q_UNUSED(filePath)
     return NoOpen;
 }
-
-IVersionControl::TopicCache::~TopicCache() = default;
-
-/*!
-   Returns the topic for repository under \a topLevel.
-
-   If the cache for \a topLevel is valid, it will be used. Otherwise it will be refreshed.
- */
-QString IVersionControl::TopicCache::topic(const FilePath &topLevel)
-{
-    QTC_ASSERT(!topLevel.isEmpty(), return QString());
-    TopicData &data = m_cache[topLevel];
-    const FilePath file = trackFile(topLevel);
-
-    if (file.isEmpty())
-        return QString();
-    const QDateTime lastModified = file.lastModified();
-    if (lastModified == data.timeStamp)
-        return data.topic;
-    data.timeStamp = lastModified;
-    return data.topic = refreshTopic(topLevel);
-}
-
 void IVersionControl::fillLinkContextMenu(QMenu *, const FilePath &, const QString &)
 {
 }

src/plugins/coreplugin/iversioncontrol.h

@@ -8,16 +8,15 @@
 #include <utils/id.h>
 #include <utils/filepath.h>
 
-#include <QDateTime>
 #include <QFlags>
-#include <QHash>
 #include <QObject>
-#include <QString>
 
 QT_FORWARD_DECLARE_CLASS(QMenu);
 
 namespace Core {
 
+namespace Internal { class IVersionControlPrivate; }
+
 class CORE_EXPORT IVersionControl : public QObject
 {
     Q_OBJECT
@@ -43,28 +42,6 @@ public:
         OpenMandatory  /*!< Files must always be opened by the VCS */
     };
 
-    class CORE_EXPORT TopicCache
-    {
-    public:
-        virtual ~TopicCache();
-        QString topic(const Utils::FilePath &topLevel);
-
-    protected:
-        virtual Utils::FilePath trackFile(const Utils::FilePath &repository) = 0;
-        virtual QString refreshTopic(const Utils::FilePath &repository) = 0;
-
-    private:
-        class TopicData
-        {
-        public:
-            QDateTime timeStamp;
-            QString topic;
-        };
-
-        QHash<Utils::FilePath, TopicData> m_cache;
-
-    };
-
     IVersionControl();
     ~IVersionControl() override;
 
@@ -218,7 +195,14 @@ public:
     };
     virtual RepoUrl getRepoUrl(const QString &location) const;
 
-    void setTopicCache(TopicCache *topicCache);
+    // Topic cache
+    using FileTracker = std::function<Utils::FilePath(const Utils::FilePath &)>;
+    Utils::FilePath trackFile(const Utils::FilePath &repository);
+    void setTopicFileTracker(const FileTracker &fileTracker);
+
+    using TopicRefresher = std::function<QString(const Utils::FilePath &)>;
+    QString refreshTopic(const Utils::FilePath &repository);
+    void setTopicRefresher(const TopicRefresher &topicRefresher);
 
 signals:
     void repositoryChanged(const Utils::FilePath &repository);
@@ -226,7 +210,7 @@ signals:
     void configurationChanged();
 
 private:
-    TopicCache *m_topicCache = nullptr;
+    Internal::IVersionControlPrivate *d;
 };
 
 } // namespace Core

src/plugins/fossil/fossilplugin.cpp

@@ -61,23 +61,6 @@ using namespace std::placeholders;
 
 namespace Fossil::Internal {
 
-class FossilTopicCache final : public IVersionControl::TopicCache
-{
-public:
-    FossilTopicCache() = default;
-
-protected:
-    FilePath trackFile(const FilePath &repository) final
-    {
-        return repository.pathAppended(Constants::FOSSILREPO);
-    }
-
-    QString refreshTopic(const FilePath &repository) final
-    {
-        return fossilClient().synchronousTopic(repository);
-    }
-};
-
 class FossilPluginPrivate final : public VersionControlBase
 {
 public:
@@ -222,7 +205,13 @@ FossilPluginPrivate::FossilPluginPrivate()
 {
     Context context(Constants::FOSSIL_CONTEXT);
 
-    setTopicCache(new FossilTopicCache);
+    setTopicFileTracker([](const FilePath &repository) {
+        return repository.pathAppended(Constants::FOSSILREPO);
+    });
+    setTopicRefresher([](const FilePath &repository) {
+        return fossilClient().synchronousTopic(repository);
+    });
+
     connect(&fossilClient(), &VcsBaseClient::changed, this, &FossilPluginPrivate::changed);
 
     m_commandLocator = new CommandLocator("Fossil", "fossil", "fossil", this);

src/plugins/git/gitplugin.cpp

@@ -382,25 +382,6 @@ public:
 
 static GitPluginPrivate *dd = nullptr;
 
-class GitTopicCache : public IVersionControl::TopicCache
-{
-public:
-    GitTopicCache() {}
-
-protected:
-    FilePath trackFile(const FilePath &repository) override
-    {
-        const FilePath gitDir = gitClient().findGitDirForRepository(repository);
-        return gitDir.isEmpty() ? FilePath() : gitDir / "HEAD";
-    }
-
-    QString refreshTopic(const FilePath &repository) override
-    {
-        emit dd->repositoryChanged(repository);
-        return gitClient().synchronousTopic(repository);
-    }
-};
-
 GitPluginPrivate::~GitPluginPrivate()
 {
     cleanCommitMessageFile();
@@ -560,7 +541,14 @@ GitPluginPrivate::GitPluginPrivate()
 {
     dd = this;
 
-    setTopicCache(new GitTopicCache);
+    setTopicFileTracker([](const FilePath &repository) {
+        const FilePath gitDir = gitClient().findGitDirForRepository(repository);
+        return gitDir.isEmpty() ? FilePath() : gitDir / "HEAD";
+    });
+    setTopicRefresher([this](const FilePath &repository) {
+        emit repositoryChanged(repository);
+        return gitClient().synchronousTopic(repository);
+    });
 
     m_fileActions.reserve(10);
     m_projectActions.reserve(10);

src/plugins/mercurial/mercurialplugin.cpp

@@ -51,23 +51,6 @@ using namespace std::placeholders;
 
 namespace Mercurial::Internal {
 
-class MercurialTopicCache : public Core::IVersionControl::TopicCache
-{
-public:
-    MercurialTopicCache() = default;
-
-protected:
-    FilePath trackFile(const FilePath &repository) override
-    {
-        return repository.pathAppended(".hg/branch");
-    }
-
-    QString refreshTopic(const FilePath &repository) override
-    {
-        return mercurialClient().branchQuerySync(repository.toString());
-    }
-};
-
 class MercurialPluginPrivate final : public VcsBase::VersionControlBase
 {
 public:
@@ -203,7 +186,12 @@ MercurialPluginPrivate::MercurialPluginPrivate()
         [] { return new CommitEditor; }
     });
 
-    setTopicCache(new MercurialTopicCache);
+    setTopicFileTracker([](const FilePath &repository) {
+        return repository.pathAppended(".hg/branch");
+    });
+    setTopicRefresher([](const FilePath &repository) {
+        return mercurialClient().branchQuerySync(repository.toString());
+    });
 
     Core::Context context(Constants::MERCURIAL_CONTEXT);
 

src/plugins/subversion/subversionplugin.cpp

@@ -126,24 +126,6 @@ static inline QStringList svnDirectories()
     return rc;
 }
 
-class SubversionPluginPrivate;
-
-class SubversionTopicCache : public Core::IVersionControl::TopicCache
-{
-public:
-    SubversionTopicCache(SubversionPluginPrivate *plugin) :
-        m_plugin(plugin)
-    { }
-
-protected:
-    FilePath trackFile(const FilePath &repository) override;
-
-    QString refreshTopic(const FilePath &repository) override;
-
-private:
-    SubversionPluginPrivate *m_plugin;
-};
-
 class SubversionPluginPrivate final : public VcsBase::VersionControlBase
 {
 public:
@@ -312,7 +294,12 @@ SubversionPluginPrivate::SubversionPluginPrivate()
 {
     dd = this;
 
-    setTopicCache(new SubversionTopicCache(this));
+    setTopicFileTracker([this](const FilePath &repository) {
+        return FilePath::fromString(monitorFile(repository));
+    });
+    setTopicRefresher([this](const FilePath &repository) {
+        return synchronousTopic(repository);
+    });
 
     using namespace Constants;
     using namespace Core::Constants;
@@ -1153,16 +1140,6 @@ VcsCommand *SubversionPluginPrivate::createInitialCheckoutCommand(const QString
     return command;
 }
 
-FilePath SubversionTopicCache::trackFile(const FilePath &repository)
-{
-    return FilePath::fromString(m_plugin->monitorFile(repository));
-}
-
-QString SubversionTopicCache::refreshTopic(const FilePath &repository)
-{
-    return m_plugin->synchronousTopic(repository);
-}
-
 
 #ifdef WITH_TESTS