Support for deep copies via assignment operator. This will pave the way for elimination of Ptr_t and ConstPtr_t.

Src/Util/NewConfig.cpp

@@ -203,29 +203,13 @@ namespace Util
       parent.m_children[node->m_key] = node;
     }
 
-    Node::Node()
+    void Node::DeepCopy(const Node &that)
-    {
-      //std::cout << "Created " << "<null>" << " (" << this << ")" << std::endl;
-    }
-
-    Node::Node(const std::string &key)
-      : m_key(key)
-    {
-      //std::cout << "Created " << key << " (" << this << ")" << std::endl;
-    }
-
-    Node::Node(const std::string &key, const std::string &value)
-      : m_key(key),
-        m_value(value)
-    {
-      //std::cout << "Created " << key << '=' << value << " (" << this << ")" << std::endl;
-    }
-
-    // Deep copy
-    Node::Node(const Node &that)
-      : m_key(that.m_key),
-        m_value(that.m_value)
     {
+      if (this == &that)
+        return;
+      Destroy();
+      *const_cast<std::string *>(&m_key) = that.m_key;
+      m_value = that.m_value;
       for (Ptr_t child = that.m_first_child; child; child = child->m_next_sibling)
       {
         Ptr_t copied_child = std::make_shared<Node>(*child);
@@ -233,9 +217,40 @@ namespace Util
       }
     }
 
+    Node &Node::operator=(const Node &rhs)
+    {
+      DeepCopy(rhs);
+      return *this;
+    }
+
+    Node::Node()
+    {
+      //std::cout << "<<< Created " << "<null>" << " (" << this << ")" << std::endl;
+    }
+
+    Node::Node(const std::string &key)
+      : m_key(key)
+    {
+      //std::cout << "<<< Created " << key << " (" << this << ")" << std::endl;
+    }
+
+    Node::Node(const std::string &key, const std::string &value)
+      : m_key(key),
+        m_value(value)
+    {
+      //std::cout << "<<< Created " << key << '=' << value << " (" << this << ")" << std::endl;
+    }
+
+    Node::Node(const Node &that)
+      : m_key(that.m_key),
+        m_value(that.m_value)
+    {
+      DeepCopy(that);
+    }
+
     Node::~Node()
     {
-      //std::cout << "Destroyed " << m_key << " (" << this << ")" << std::endl;
+      //std::cout << ">>> Destroyed " << m_key << " (" << this << ")" << std::endl;
     }
 
     Node::Ptr_t CreateEmpty()

Src/Util/NewConfig.h

@@ -25,7 +25,17 @@ namespace Util
       std::string m_value;
       static Node s_empty_node; // key, value, and children must always be empty
 
+      void Destroy()
+      {
+        m_next_sibling.reset();
+        m_first_child.reset();
+        m_last_child.reset();
+        m_children.clear();
+        m_value.clear();
+      }
+
       void AddChild(Node &parent, Ptr_t &node);
+      void DeepCopy(const Node &that);
       Node();                   // prohibit accidental/unintentional creation of blank nodes
       friend Ptr_t CreateEmpty();
 
@@ -199,6 +209,7 @@ namespace Util
       std::string ToString(size_t indent_level = 0) const;
       Node &Add(const std::string &key, const std::string &value = "");
       void Set(const std::string &key, const std::string &value);
+      Node &operator=(const Node &rhs);
       Node(const std::string &key);
       Node(const std::string &key, const std::string &value);
       Node(const Node &that);

Src/Util/Test_Config.cpp

@@ -63,12 +63,25 @@ int main()
   std::cout << "game/roms/crom/name=" << global["game/roms/crom/name"].Value() << " (expected: bar.bin)" << std::endl << std::endl;
   test_results.push_back({ "Lookup", global["game/roms/crom/name"].Value() == "bar.bin" });
     
-  // Make a copy
+  // Make a copy using copy constructor
-  std::cout << "Copy:" << std::endl << std::endl;
+  std::cout << "Copy constructed:" << std::endl << std::endl;
   Util::Config::Node::Ptr_t copy = std::make_shared<Util::Config::Node>(*root);
   copy->Print();
   std::cout << std::endl;
-  test_results.push_back({ "Copy", copy->ToString() == root->ToString() });
+  test_results.push_back({ "Copy constructed", copy->ToString() == root->ToString() });
+  
+  // Make a copy using assignment operator
+  std::cout << "Copy by assignment:" << std::endl << std::endl;
+  Util::Config::Node copy2("foo", "bar");
+  copy2.Add("x/y/z", "test");
+  copy2.Add("dummy", "value");
+  std::cout << "Initially set to:" << std::endl;
+  copy2.Print();
+  copy2 = *root;
+  std::cout << "Copy of \"global\":" << std::endl;
+  copy2.Print();
+  std::cout << std::endl;
+  test_results.push_back({ "Copy by assignment", copy2.ToString() == root->ToString() });
 
   // Parse from XML
   const char *xml =