Fix memory leak: do not add trait duplications to @defined_traits

Closes #588

lib/factory_girl/definition.rb

@@ -6,7 +6,7 @@ module FactoryGirl
     def initialize(name = nil, base_traits = [])
       @declarations      = DeclarationList.new(name)
       @callbacks         = []
-      @defined_traits    = []
+      @defined_traits    = Set.new
       @to_create         = nil
       @base_traits       = base_traits
       @additional_traits = []
@@ -77,7 +77,7 @@ module FactoryGirl
     end
 
     def define_trait(trait)
-      @defined_traits << trait
+      @defined_traits.add(trait)
     end
 
     def define_constructor(&block)

spec/factory_girl/definition_spec.rb

@@ -32,7 +32,13 @@ describe FactoryGirl::Definition, "defining traits" do
   it "maintains a list of traits" do
     subject.define_trait(trait_1)
     subject.define_trait(trait_2)
-    expect(subject.defined_traits).to eq [trait_1, trait_2]
+    expect(subject.defined_traits).to include(trait_1, trait_2)
+  end
+
+  it "adds only unique traits" do
+    subject.define_trait(trait_1)
+    subject.define_trait(trait_1)
+    expect(subject.defined_traits.size).to eq 1
   end
 end
 

spec/support/matchers/trait.rb

@@ -1,6 +1,8 @@
 RSpec::Matchers.define :have_trait do |trait_name|
   match do |instance|
-    instance.defined_traits.include?(FactoryGirl::Trait.new(trait_name, &@block))
+    instance.defined_traits.any? do |trait|
+      trait.name == trait_name && trait.send(:block) == @block
+    end
   end
 
   chain :with_block do |block|