diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 44cf0d3b81..151aeb2b60 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -629,10 +629,9 @@ private
   end
 
   def set_instance_variable(type)
-    unless instance_variable_defined? "@#{type}"
-      class_value = self.class.send(type)
-      instance_variable_set("@#{type}", class_value) if class_value
-    end
+    return if instance_variable_defined? "@#{type}"
+    class_value = self.class.send(type)
+    instance_variable_set("@#{type}", class_value) if class_value
   end
 
   def method_added method