1 files changed, 97 insertions, 0 deletions
diff --git a/actionpack/lib/action_view/renderer/template_renderer.rb b/actionpack/lib/action_view/renderer/template_renderer.rb
new file mode 100644
index 0000000000..a9076760c5
--- /dev/null
+++ b/actionpack/lib/action_view/renderer/template_renderer.rb
@@ -0,0 +1,97 @@
+require 'set'
+require 'active_support/core_ext/object/try'
+require 'active_support/core_ext/array/wrap'
+require 'action_view/renderer/abstract_renderer'
+
+module ActionView
+  class TemplateRenderer < AbstractRenderer #:nodoc:
+    attr_reader :rendered
+
+    def initialize(view)
+      super
+      @rendered = Set.new
+    end
+
+    def render(options)
+      wrap_formats(options[:template] || options[:file]) do
+        template = determine_template(options)
+        render_template(template, options[:layout], options[:locals])
+      end
+    end
+
+    def render_once(options)
+      paths, locals = options[:once], options[:locals] || {}
+      layout, keys, prefix = options[:layout], locals.keys, options[:prefix]
+
+      raise "render :once expects a String or an Array to be given" unless paths
+
+      render_with_layout(layout, locals) do
+        contents = []
+        Array.wrap(paths).each do |path|
+          template = find_template(path, prefix, false, keys)
+          contents << render_template(template, nil, locals) if @rendered.add?(template)
+        end
+        contents.join("\n")
+      end
+    end
+
+    # Determine the template to be rendered using the given options.
+    def determine_template(options) #:nodoc:
+      keys = options[:locals].try(:keys) || []
+
+      if options.key?(:text)
+        Template::Text.new(options[:text], formats.try(:first))
+      elsif options.key?(:file)
+        with_fallbacks { find_template(options[:file], options[:prefix], false, keys) }
+      elsif options.key?(:inline)
+        handler = Template.handler_class_for_extension(options[:type] || "erb")
+        Template::Inline.new(options[:inline], handler, :locals => keys)
+      elsif options.key?(:template)
+        options[:template].respond_to?(:render) ?
+          options[:template] : find_template(options[:template], options[:prefix], false, keys)
+      end
+    end
+
+    # Renders the given template. An string representing the layout can be
+    # supplied as well.
+    def render_template(template, layout_name = nil, locals = {}) #:nodoc:
+      lookup_context.freeze_formats(template.formats, true)
+      view, locals = @view, locals || {}
+
+      render_with_layout(layout_name, locals) do |layout|
+        instrument(:template, :identifier => template.identifier, :layout => layout.try(:virtual_path)) do
+          template.render(view, locals) { |*name| view._layout_for(*name) }
+        end
+      end
+    end
+
+    def render_with_layout(path, locals) #:nodoc:
+      layout  = path && find_layout(path, locals.keys)
+      content = yield(layout)
+
+      if layout
+        view = @view
+        view.store_content_for(:layout, content)
+        layout.render(view, locals){ |*name| view._layout_for(*name) }
+      else
+        content
+      end
+    end
+
+    # This is the method which actually finds the layout using details in the lookup
+    # context object. If no layout is found, it checks if at least a layout with
+    # the given name exists across all details before raising the error.
+    def find_layout(layout, keys)
+      begin
+        with_layout_format do
+          layout =~ /^\// ?
+            with_fallbacks { find_template(layout, nil, false, keys) } : find_template(layout, nil, false, keys)
+        end
+      rescue ActionView::MissingTemplate => e
+        update_details(:formats => nil) do
+          raise unless template_exists?(layout)
+        end
+      end
+    end
+  end
+end
+\ No newline at end of file