Move proxy strategy checking to proxy

lib/factory_girl/factory.rb

@@ -168,18 +168,12 @@ module FactoryGirl
       options.assert_valid_keys(:class, :parent, :default_strategy, :aliases, :traits)
 
       if options[:default_strategy]
-        assert_valid_strategy(options[:default_strategy])
+        Proxy.ensure_strategy_exists!(options[:default_strategy])
         $stderr.puts "DEPRECATION WARNING: default_strategy is deprecated."
         $stderr.puts "Override to_create if you need to prevent a call to #save!."
       end
     end
 
-    def assert_valid_strategy(strategy)
-      unless Proxy.const_defined? strategy.to_s.camelize
-        raise ArgumentError, "Unknown strategy: #{strategy}"
-      end
-    end
-
     def trait_for(name)
       @defined_traits.detect {|trait| trait.name == name }
     end

lib/factory_girl/proxy.rb

@@ -75,5 +75,11 @@ module FactoryGirl
     def result(to_create)
       raise NotImplementedError, "Strategies must return a result"
     end
+
+    def self.ensure_strategy_exists!(strategy)
+      unless Proxy.const_defined? strategy.to_s.camelize
+        raise ArgumentError, "Unknown strategy: #{strategy}"
+      end
+    end
   end
 end

spec/factory_girl/factory_spec.rb

@@ -197,8 +197,8 @@ describe FactoryGirl::Factory do
     FactoryGirl.register_factory(factory_with_stub_strategy)
   end
 
-  it "raises an ArgumentError when trying to use a non-existent strategy" do
-    expect { factory_with_non_existent_strategy }.to raise_error(ArgumentError)
+  it "raises when trying to use a non-existent strategy" do
+    expect { factory_with_non_existent_strategy }.to raise_error
   end
 
   it "creates a new factory with a specified default strategy" do

spec/factory_girl/proxy_spec.rb

@@ -42,3 +42,13 @@ describe FactoryGirl::Proxy, "when running callbacks" do
     callback_result.should == [:after_build_one]
   end
 end
+
+describe FactoryGirl::Proxy, ".ensure_strategy_exists!" do
+  it "raises when passed a nonexistent strategy" do
+    expect { FactoryGirl::Proxy.ensure_strategy_exists!(:nonexistent) }.to raise_error(ArgumentError, "Unknown strategy: nonexistent")
+  end
+
+  it "doesn't raise when passed a valid strategy" do
+    expect { FactoryGirl::Proxy.ensure_strategy_exists!(:create) }.to_not raise_error
+  end
+end