[education/rkward] rkward: Clear object model when restarting backend

[Thomas Friedrichsmeier]

Git commit be89b0ac05e08afd9bcb4245c8bfe123c97608a2 by Thomas Friedrichsmeier.
Committed on 04/06/2022 at 16:48.
Pushed by tfry into branch 'master'.

Clear object model when restarting backend

M  +25   -15   rkward/core/robjectlist.cpp
M  +2    -3    rkward/core/robjectlist.h
M  +4    -6    rkward/misc/rkobjectlistview.cpp
M  +5    -2    rkward/rkward.cpp

https://invent.kde.org/education/rkward/commit/be89b0ac05e08afd9bcb4245c8bfe123c97608a2

diff --git a/rkward/core/robjectlist.cpp b/rkward/core/robjectlist.cpp
index 0e879e70..11c16d0c 100644
--- a/rkward/core/robjectlist.cpp
+++ b/rkward/core/robjectlist.cpp
@@ -1,6 +1,6 @@
 /*
 robjectlist - This file is part of RKWard (https://rkward.kde.org). Created: Wed Aug 18 2004
-SPDX-FileCopyrightText: 2004-2019 by Thomas Friedrichsmeier <thomas.friedrichsmeier at kdemail.net>
+SPDX-FileCopyrightText: 2004-2022 by Thomas Friedrichsmeier <thomas.friedrichsmeier at kdemail.net>
 SPDX-FileContributor: The RKWard Team <rkward-devel at kde.org>
 SPDX-License-Identifier: GPL-2.0-or-later
 */
@@ -26,25 +26,23 @@ SPDX-License-Identifier: GPL-2.0-or-later
 #include "../debug.h"
 
 // static
-RObjectList *RObjectList::object_list = 0;
+RObjectList *RObjectList::object_list = nullptr;
 
 RObjectList::RObjectList () : RContainerObject (0, QString ()) {
 	RK_TRACE (OBJECTS);
+	RK_ASSERT(!object_list);
 	object_list = this;
 
 	update_timer = new QTimer (this);
 	update_timer->setSingleShot (true);
-	connect (update_timer, &QTimer::timeout, this, &RObjectList::timeout);
-	
-	//update_timer->start (AUTO_UPDATE_INTERVAL, true);
-	
+	connect(update_timer, &QTimer::timeout, this, [this]() { updateFromR(0); });
+	update_chain = 0;
+
 	type = RObject::Workspace;
 	name = "search()";
-	
-	update_chain = 0;
 
 	globalenv = new REnvironmentObject (0, ".GlobalEnv");
-	globalenv->updateFromR (update_chain);
+	globalenv->updateFromR(nullptr);
 
    // TODO: Do we really need tracker notification at this stage?
 	RKOrphanNamespacesObject *obj = new RKOrphanNamespacesObject (this);
@@ -59,6 +57,24 @@ RObjectList::~RObjectList () {
 	delete globalenv;
 }
 
+// static
+void RObjectList::init() {
+	RK_TRACE(OBJECTS);
+	if (!object_list) {
+		 new RObjectList();
+	} else {
+		auto *globalenv = object_list->globalenv; // easier typing
+		for (int i = globalenv->numChildren() - 1; i >= 0; --i) {
+			globalenv->removeChild(globalenv->findChildByIndex(i), true);
+		}
+		object_list->updateEnvironments(QStringList() << ".GlobalEnv", false);
+		object_list->updateNamespaces(QStringList());
+		// TODO: For unkonwn reasons, a ghost object remains inside globalenv in the QSortFilterProxyModel (qt 5.12.8). Get rid of it with a model reset
+		RKModificationTracker::instance()->beginResetModel();
+		RKModificationTracker::instance()->endResetModel();
+	}
+}
+
 QString RObjectList::getObjectDescription () const {
 	return i18n ("This section contains environments that are not part of <i>.GlobalEnv</i> / your \"workspace\". Most importantly, this includes loaded packages, but also objects added to R's <i>search()<i>-path using <i>attach()</i>.");
 }
@@ -299,12 +315,6 @@ bool RObjectList::updateStructure (RData *) {
 	return true;
 }
 
-void RObjectList::timeout () {
-	RK_TRACE (OBJECTS);
-
-	updateFromR (0);
-}
-
 QString RObjectList::renameChildCommand (RObject *object, const QString &new_name) const {
 	RK_TRACE (OBJECTS);
 
diff --git a/rkward/core/robjectlist.h b/rkward/core/robjectlist.h
index 6e7ddc0a..24253af0 100644
--- a/rkward/core/robjectlist.h
+++ b/rkward/core/robjectlist.h
@@ -1,6 +1,6 @@
 /*
 robjectlist - This file is part of the RKWard project. Created: Wed Aug 18 2004
-SPDX-FileCopyrightText: 2004-2019 by Thomas Friedrichsmeier <thomas.friedrichsmeier at kdemail.net>
+SPDX-FileCopyrightText: 2004-2022 by Thomas Friedrichsmeier <thomas.friedrichsmeier at kdemail.net>
 SPDX-FileContributor: The RKWard Team <rkward-devel at kde.org>
 SPDX-License-Identifier: GPL-2.0-or-later
 */
@@ -50,6 +50,7 @@ public:
 
 	static RObjectList *getObjectList () { return object_list; };
 	static REnvironmentObject *getGlobalEnv () { return object_list->globalenv; };
+	static void init();
 
 	/** detach the given list of packages (if the packages are loaded, and safe to remove)
 	@returns a list of error messages (usually empty) */
@@ -57,8 +58,6 @@ public:
 	/** A pseudo object containing as children all loaded namespaces which do not belong to a package on the search path */
 	RKOrphanNamespacesObject* orphanNamespacesObject () const { return orphan_namespaces; };
 	QString getObjectDescription () const override;
-public slots:
-	void timeout ();
 signals:
 /// emitted when the list of objects is about to be updated	// TODO: remove me
 	void updateStarted ();
diff --git a/rkward/misc/rkobjectlistview.cpp b/rkward/misc/rkobjectlistview.cpp
index 32719db6..1d623abc 100644
--- a/rkward/misc/rkobjectlistview.cpp
+++ b/rkward/misc/rkobjectlistview.cpp
@@ -193,12 +193,10 @@ void RKObjectListView::settingsChanged () {
 	RK_TRACE (APP);
 
 	setRootObject (root_object);
-	if (!root_object) {
-		setFirstColumnSpanned (0, QModelIndex (), true);
-		setItemDelegateForRow (0, rkdelegate);
-		setFirstColumnSpanned (1, QModelIndex (), true);
-		setItemDelegateForRow (1, rkdelegate);
-	}
+	setFirstColumnSpanned (0, QModelIndex (), true);
+	setItemDelegateForRow (0, rkdelegate);
+	setFirstColumnSpanned (1, QModelIndex (), true);
+	setItemDelegateForRow (1, rkdelegate);
 	resizeColumnToContents (0);
 }
 
diff --git a/rkward/rkward.cpp b/rkward/rkward.cpp
index 4d6ef19d..d2a7b870 100644
--- a/rkward/rkward.cpp
+++ b/rkward/rkward.cpp
@@ -386,7 +386,7 @@ void RKWardMainWindow::startR () {
 
 	RInterface::create();
 	connect(RInterface::instance(), &RInterface::backendStatusChanged, this, &RKWardMainWindow::setRStatus);
-	new RObjectList ();
+	RObjectList::init();
 
 	RObjectBrowser::mainBrowser ()->unlock ();
 }
@@ -615,7 +615,10 @@ void RKWardMainWindow::initActions() {
 	auto restart_r = actionCollection()->addAction("restart_r");
 	restart_r->setText(i18n("Restart R Backend"));
 	connect(restart_r, &QAction::triggered, this, [this]() {
-		if (RInterface::instance()->backendIsDead()) startR();
+		if (RInterface::instance()->backendIsDead()) {
+			delete RInterface::instance();
+			startR();
+		}
 	});
 }