Fixed bc5896e, and added test case for the caching bug it originally introduced.

actionpack/lib/action_view/base.rb

@@ -332,6 +332,9 @@ module ActionView #:nodoc:
       end
     end
 
+    extend ActiveSupport::Memoizable
+    memoize :pick_template
+
     private
       # Renders the template present at <tt>template_path</tt>. The hash in <tt>local_assigns</tt>
       # is made available as local variables.

actionpack/lib/action_view/partials.rb

@@ -102,6 +102,8 @@ module ActionView
   #
   # As you can see, the <tt>:locals</tt> hash is shared between both the partial and its layout.
   module Partials
+    extend ActiveSupport::Memoizable
+
     private
       def render_partial(partial_path, object_assigns = nil, local_assigns = {}) #:nodoc:
         local_assigns ||= {}
@@ -129,14 +131,12 @@ module ActionView
 
         local_assigns = local_assigns ? local_assigns.clone : {}
         spacer = partial_spacer_template ? render(:partial => partial_spacer_template) : ''
-        _paths = {}
-        _templates = {}
 
         index = 0
         collection.map do |object|
           _partial_path ||= partial_path || ActionController::RecordIdentifier.partial_path(object, controller.class.controller_path)
-          path = _paths[_partial_path] ||= find_partial_path(_partial_path)
-          template = _templates[path] ||= pick_template(path)
+          path = find_partial_path(_partial_path)
+          template = pick_template(path)
           local_assigns[template.counter_name] = index
           result = template.render_partial(self, object, local_assigns, as)
           index += 1
@@ -153,5 +153,6 @@ module ActionView
           "_#{partial_path}"
         end
       end
+      memoize :find_partial_path
   end
 end

actionpack/lib/action_view/renderable.rb

@@ -84,7 +84,7 @@ module ActionView
       # The template will be compiled if the file has not been compiled yet, or
       # if local_assigns has a new key, which isn't supported by the compiled code yet.
       def recompile?(symbol)
-        !(frozen? && Base::CompiledTemplates.method_defined?(symbol))
+        !(ActionView::PathSet::Path.eager_load_templates? && Base::CompiledTemplates.method_defined?(symbol))
       end
   end
 end

actionpack/test/template/compiled_templates_test.rb

@@ -30,9 +30,12 @@ uses_mocha 'TestTemplateRecompilation' do
       assert_equal "Hello world!", render("test/hello_world.erb")
     end
 
-    def test_compiled_template_will_be_recompiled_when_rendered_if_template_is_outside_cache
+    def test_compiled_template_will_always_be_recompiled_when_eager_loaded_templates_is_off
+      ActionView::PathSet::Path.expects(:eager_load_templates?).times(4).returns(false)
       assert_equal 0, @compiled_templates.instance_methods.size
       assert_equal "Hello world!", render("#{FIXTURE_LOAD_PATH}/test/hello_world.erb")
+      ActionView::Template.any_instance.expects(:compile!).times(3)
+      3.times { assert_equal "Hello world!", render("#{FIXTURE_LOAD_PATH}/test/hello_world.erb") }
       assert_equal 1, @compiled_templates.instance_methods.size
     end