module ActionView::Helpers::RenderingHelper

as the locals hash.
If no options hash is passed or :update specified, the default is to render a partial and use the second parameter

object.
type of text/plain from ActionDispatch::Response
* :body - Renders the text passed in, and inherits the content
text/html.
performs HTML escape on the string first. Setting the content type as
* :html - Renders the HTML safe string passed in out, otherwise
type as text/plain.
* :plain - Renders the text passed in out. Setting the content
* :text - Renders the text passed in out.
* :inline - Renders an inline template similar to how it's done in the controller.
* :file - Renders an explicit template file (this used to be the old default), add :locals to pass in those.
* :partial - See ActionView::PartialRenderer.

Returns the result of a render that's dictated by the options hash. The primary options are:

def render(options = {}, locals = {}, &block)
  case options
  when Hash
    if block_given?
      view_renderer.render_partial(self, options.merge(:partial => options[:layout]), &block)
    else
      view_renderer.render(self, options)
    end
  else
    view_renderer.render_partial(self, :partial => options, :locals => locals, &block)
  end
end