NOISSUE Add NullInstance for instances that can't be loaded

logic/NullInstance.h

@@ -0,0 +1,61 @@
+#include "BaseInstance.h"
+
+class NullInstance: public BaseInstance
+{
+public:
+	NullInstance(SettingsObjectPtr globalSettings, SettingsObjectPtr settings, const QString& rootDir)
+	:BaseInstance(globalSettings, settings, rootDir)
+	{
+		setFlag(BaseInstance::VersionBrokenFlag);
+	}
+	virtual ~NullInstance() {};
+	virtual bool setIntendedVersionId(QString) override
+	{
+		return false;
+	}
+	virtual void cleanupAfterRun() override
+	{
+	}
+	virtual QString currentVersionId() const
+	{
+		return "Null";
+	};
+	virtual QString intendedVersionId() const
+	{
+		return "Null";
+	};
+	virtual void init() override
+	{
+	};
+	virtual QString getStatusbarDescription() override
+	{
+		return tr("Unknown instance type");
+	};
+	virtual bool shouldUpdate() const override
+	{
+		return false;
+	};
+	virtual QSet< QString > traits()
+	{
+		return {};
+	};
+	virtual QString instanceConfigFolder() const
+	{
+		return instanceRoot();
+	};
+	virtual BaseProcess* prepareForLaunch(AuthSessionPtr)
+	{
+		return nullptr;
+	}
+	virtual std::shared_ptr< Task > doUpdate()
+	{
+		return nullptr;
+	}
+	virtual void setShouldUpdate(bool)
+	{
+	};
+	virtual std::shared_ptr< BaseVersionList > versionList() const
+	{
+		return nullptr;
+	};
+};