From 2853b56ed599b70fa886f391ac9e4e1a8716ef50 Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Thu, 15 Aug 2013 04:52:01 -0700
Subject: [PATCH] Throw an exception when trying to get an empty Ptr's type

---
 apps/openmw/mwgui/tradeitemmodel.cpp | 41 +++++++++++++++-------------
 apps/openmw/mwworld/ptr.cpp          |  1 -
 apps/openmw/mwworld/ptr.hpp          | 19 +++++--------
 3 files changed, 29 insertions(+), 32 deletions(-)

diff --git a/apps/openmw/mwgui/tradeitemmodel.cpp b/apps/openmw/mwgui/tradeitemmodel.cpp
index b4fa4e16f..e836355d3 100644
--- a/apps/openmw/mwgui/tradeitemmodel.cpp
+++ b/apps/openmw/mwgui/tradeitemmodel.cpp
@@ -146,27 +146,30 @@ namespace MWGui
         for (size_t i=0; i<mSourceModel->getItemCount(); ++i)
         {
             ItemStack item = mSourceModel->getItem(i);
-            MWWorld::Ptr base = item.mBase;
-            if (!mMerchant.isEmpty() && Misc::StringUtils::ciEqual(base.getCellRef().mRefID, "gold_001"))
-                continue;
-            if (!mMerchant.isEmpty() && !MWWorld::Class::get(base).canSell(base, services))
-                continue;
-
-            // don't show equipped items
-            if (mMerchant.getTypeName() == typeid(ESM::NPC).name())
+            if(!mMerchant.isEmpty())
             {
-                bool isEquipped = false;
-                MWWorld::InventoryStore& store = MWWorld::Class::get(mMerchant).getInventoryStore(mMerchant);
-                for (int slot=0; slot<MWWorld::InventoryStore::Slots; ++slot)
-                {
-                    MWWorld::ContainerStoreIterator equipped = store.getSlot(slot);
-                    if (equipped == store.end())
-                        continue;
-                    if (*equipped == base)
-                        isEquipped = true;
-                }
-                if (isEquipped)
+                MWWorld::Ptr base = item.mBase;
+                if(Misc::StringUtils::ciEqual(base.getCellRef().mRefID, "gold_001"))
                     continue;
+                if(!MWWorld::Class::get(base).canSell(base, services))
+                    continue;
+
+                // don't show equipped items
+                if(mMerchant.getTypeName() == typeid(ESM::NPC).name())
+                {
+                    bool isEquipped = false;
+                    MWWorld::InventoryStore& store = MWWorld::Class::get(mMerchant).getInventoryStore(mMerchant);
+                    for (int slot=0; slot<MWWorld::InventoryStore::Slots; ++slot)
+                    {
+                        MWWorld::ContainerStoreIterator equipped = store.getSlot(slot);
+                        if (equipped == store.end())
+                            continue;
+                        if (*equipped == base)
+                            isEquipped = true;
+                    }
+                    if (isEquipped)
+                        continue;
+                }
             }
 
             // don't show items that we borrowed to someone else
diff --git a/apps/openmw/mwworld/ptr.cpp b/apps/openmw/mwworld/ptr.cpp
index 88bb10122..34fe7fa08 100644
--- a/apps/openmw/mwworld/ptr.cpp
+++ b/apps/openmw/mwworld/ptr.cpp
@@ -5,7 +5,6 @@
 
 #include "containerstore.hpp"
 
-const std::string MWWorld::Ptr::sEmptyString;
 
 ESM::CellRef& MWWorld::Ptr::getCellRef() const
 {
diff --git a/apps/openmw/mwworld/ptr.hpp b/apps/openmw/mwworld/ptr.hpp
index 240dd83f2..51c1530d7 100644
--- a/apps/openmw/mwworld/ptr.hpp
+++ b/apps/openmw/mwworld/ptr.hpp
@@ -12,8 +12,6 @@ namespace MWWorld
 
     class Ptr
     {
-            static const std::string sEmptyString;
-
         public:
 
             typedef MWWorld::CellStore CellStore;
@@ -24,8 +22,10 @@ namespace MWWorld
             ContainerStore *mContainerStore;
 
         public:
-
-            Ptr() : mRef(0), mCell(0), mContainerStore(0) { }
+            Ptr(MWWorld::LiveCellRefBase *liveCellRef=0, CellStore *cell=0)
+              : mRef(liveCellRef), mCell(cell), mContainerStore(0)
+            {
+            }
 
             bool isEmpty() const
             {
@@ -34,14 +34,9 @@ namespace MWWorld
 
             const std::string& getTypeName() const
             {
-                return mRef ? mRef->mTypeName : sEmptyString;
-            }
-
-            Ptr (MWWorld::LiveCellRefBase *liveCellRef, CellStore *cell)
-            : mContainerStore (0)
-            {
-                mRef = liveCellRef;
-                mCell = cell;
+                if(mRef != 0)
+                    return mRef->mTypeName;
+                throw std::runtime_error("Can't get type name from an empty object.");
             }
 
             template<typename T>