Allow a node to be renamed

lib/tree.rb

@@ -93,7 +93,7 @@ class TreeNode
 
     # @!group Core Attributes
 
-    # @!attribute [r] name
+    # @!attribute [rw] name
     #
     # Name of this node.  Expected to be unique within the tree.
     #
@@ -105,8 +105,12 @@ class TreeNode
     # retain unique names within the tree structure, and use the
     # +content+ attribute for any non-unique node requirements.
     #
+    # If you want to change the name, you probably want to call +rename+
+    # instead.
+    #
     # @see content
-    attr_reader   :name
+    # @see rename
+    attr_accessor   :name
 
     # @!attribute [rw] content
     # Content of this node.  Can be +nil+.  Note that there is no
@@ -381,6 +385,35 @@ def insertion_range
 
     private :insertion_range
 
+    # Renames the node and updates the parent's reference to it
+    #
+    # @param [Object] name Name of the node.  Conventional usage is to pass a String
+    #   (Integer names may cause *surprises*)
+    #
+    # @return [Object] The old name
+    def rename(new_name)
+      old_name = @name
+
+      if is_root?
+        @name = new_name
+      else
+        @parent.rename_child @name, new_name
+      end
+
+      old_name
+    end
+
+    # Renames the specified child node 
+    #
+    # @param [Object] name old Name of the node. Conventional usage is to pass
+    #   a String (Integer names may cause *surprises*)
+    #
+    # @param [Object] name new Name of the node. Conventional usage is to pass
+    #   a String (Integer names may cause *surprises*)
+    def rename_child(old_name, new_name)
+      @children_hash[new_name] = @children_hash.delete(old_name)
+      @children_hash[new_name].name= new_name
+    end
 
     # Replaces the specified child node with another child node on this node.
     #

test/test_tree.rb

@@ -1586,6 +1586,27 @@ def test_merge_bang
       assert_raise(TypeError) { @root.merge!('ROOT') }
     end
 
+    def test_name_accessor
+      setup_test_tree
+
+      assert_equal 'ROOT', @root.name, "Name should be 'ROOT'"
+
+      @root.name = 'ROOT2'
+
+      assert_equal 'ROOT2', @root.name, "Name should be 'ROOT2'"
+    end
+
+    def test_renam
+      setup_test_tree
+
+      @root.rename 'ALT_ROOT'
+      assert_equal('ALT_ROOT', @root.name, "Name should be 'ALT_ROOT'")
+
+      @child1.rename 'ALT_Child1'
+      assert_equal('ALT_Child1', @child1.name)
+      assert_equal('ALT_Child1', @child1.name, "Name should be 'ALT_Child1'")
+      assert_equal(@child1, @root['ALT_Child1'], 'Should be able to access from parent using new name')
+    end
   end
 end