Fix a possible crash on shutdown while executing VcsCommand

Add a global synchronizer to the VcsPlugin.

Fixes: QTCREATORBUG-25744
Change-Id: I97578f4a5b5275071aa0253a22fc9ab2f90d9b75
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/vcsbase/vcscommand.cpp

@@ -26,6 +26,7 @@
 #include "vcscommand.h"
 #include "vcsbaseplugin.h"
 #include "vcsoutputwindow.h"
+#include "vcsplugin.h"
 
 #include <coreplugin/documentmanager.h>
 #include <coreplugin/vcsmanager.h>
@@ -78,6 +79,12 @@ void VcsCommand::runCommand(SynchronousProcess &proc,
     emitRepositoryChanged(workingDirectory);
 }
 
+void VcsCommand::addTask(QFuture<void> &future)
+{
+    Core::ShellCommand::addTask(future);
+    Internal::VcsPlugin::addFuture(future);
+}
+
 void VcsCommand::emitRepositoryChanged(const QString &workingDirectory)
 {
     if (m_preventRepositoryChanged || !(flags() & VcsCommand::ExpectRepoChanges))

src/plugins/vcsbase/vcscommand.h

@@ -51,6 +51,9 @@ public:
                     const Utils::CommandLine &command,
                     const QString &workDirectory = {}) override;
 
+protected:
+    void addTask(QFuture<void> &future) override;
+
 private:
     void emitRepositoryChanged(const QString &workingDirectory);
 

src/plugins/vcsbase/vcsplugin.cpp

@@ -45,6 +45,7 @@
 #include <projectexplorer/project.h>
 #include <projectexplorer/projecttree.h>
 
+#include <utils/futuresynchronizer.h>
 #include <utils/macroexpander.h>
 
 #include <QDebug>
@@ -60,6 +61,7 @@ class VcsPluginPrivate
 public:
     CommonOptionsPage m_settingsPage;
     QStandardItemModel *m_nickNameModel = nullptr;
+    Utils::FutureSynchronizer m_synchronizer;
 };
 
 static VcsPlugin *m_instance = nullptr;
@@ -71,6 +73,7 @@ VcsPlugin::VcsPlugin()
 
 VcsPlugin::~VcsPlugin()
 {
+    d->m_synchronizer.waitForFinished();
     VcsOutputWindow::destroy();
     m_instance = nullptr;
     delete d;
@@ -82,6 +85,7 @@ bool VcsPlugin::initialize(const QStringList &arguments, QString *errorMessage)
     Q_UNUSED(errorMessage)
 
     d = new VcsPluginPrivate;
+    d->m_synchronizer.setCancelOnWait(true);
 
     EditorManager::addCloseEditorListener([this](IEditor *editor) -> bool {
         bool result = true;
@@ -140,6 +144,11 @@ VcsPlugin *VcsPlugin::instance()
     return m_instance;
 }
 
+void VcsPlugin::addFuture(const QFuture<void> &future)
+{
+    m_instance->d->m_synchronizer.addFuture(future);
+}
+
 CommonVcsSettings &VcsPlugin::settings() const
 {
     return d->m_settingsPage.settings();

src/plugins/vcsbase/vcsplugin.h

@@ -27,6 +27,8 @@
 
 #include <extensionsystem/iplugin.h>
 
+#include <QFuture>
+
 QT_BEGIN_NAMESPACE
 class QStandardItemModel;
 QT_END_NAMESPACE
@@ -51,6 +53,7 @@ public:
     bool initialize(const QStringList &arguments, QString *errorMessage) override;
 
     static VcsPlugin *instance();
+    static void addFuture(const QFuture<void> &future);
 
     CommonVcsSettings &settings() const;