Commit 84b475c

@@ -1,3 +1,5 @@
+require_relative "../utility/block_visitor"
+
 class BinaryTree
   def push(item)
     if @root
@@ -17,6 +19,10 @@ class BinaryTree
     @root.accept(visitor, traversal) if @root
   end
 
+  def each(&block)
+    accept(BlockVisitor.new(&block))
+  end
+
   class BinaryTreeNode
     attr_reader :left, :right, :data
 

@@ -0,0 +1,9 @@
+class BlockVisitor
+  def initialize(&block)
+    @block = block
+  end
+
+  def visit(item)
+    @block.call(item)
+  end
+end

@@ -13,11 +13,20 @@ describe BinaryTree do
   end
 
   context "when many items are pushed on to the tree" do
-    it "should increase the size" do
+    before :each do
       10.times do |n|
         sut.push(n)
       end
+    end
+
+    it "should increase the size" do
       sut.size.should == 10
     end
+
+    it "can iterate through each item" do
+      sut.each do |item|
+        item.should_not be_nil
+      end
+    end
   end
 end