Ensure that iterating over each registered factory returns them uniquely

lib/factory_girl/registry.rb

@@ -16,7 +16,7 @@ module FactoryGirl
     end
 
     def each(&block)
-      @items.values.each(&block)
+      @items.values.uniq.each(&block)
     end
 
     def [](name)

spec/factory_girl/registry_spec.rb

@@ -50,6 +50,19 @@ describe FactoryGirl::Registry do
     result.should =~ [factory, other_factory]
   end
 
+  it "iterates registered factories uniquely with aliases" do
+    other_factory = FactoryGirl::Factory.new(:string, :aliases => [:awesome])
+    subject.add(factory)
+    subject.add(other_factory)
+    result = []
+
+    subject.each do |value|
+      result << value
+    end
+
+    result.should =~ [factory, other_factory]
+  end
+
   it "registers an sequence" do
     sequence = FactoryGirl::Sequence.new(:email) { |n| "somebody#{n}@example.com" }
     subject.add(sequence)