Merge pull request rails#33418 from azbshiri/document-renderer

 [ci skip] Document render options

Author: schneems

actionpack/lib/action_controller/renderer.rb

@@ -71,6 +71,21 @@ def initialize(controller, env, defaults)
     end
 
     # Render templates with any options from ActionController::Base#render_to_string.
+    #
+    # The primary options are:
+    # * <tt>:partial</tt> - See <tt>ActionView::PartialRenderer</tt> for details.
+    # * <tt>:file</tt> - Renders an explicit template file. Add <tt>:locals</tt> to pass in, if so desired.
+    #   It shouldn’t be used directly with unsanitized user input due to lack of validation.
+    # * <tt>:inline</tt> - Renders a ERB template string.
+    # * <tt>:plain</tt> - Renders provided text and sets the content type as <tt>text/plain</tt>.
+    # * <tt>:html</tt> - Renders the provided HTML safe string, otherwise
+    #   performs HTML escape on the string first. Sets the content type as <tt>text/html</tt>.
+    # * <tt>:json</tt> - Renders the provided hash or object in JSON. You don't
+    #   need to call <tt>.to_json<tt> on the object you want to render.
+    # * <tt>:body</tt> - Renders provided text and sets content type of <tt>text/plain</tt>.
+    #
+    # If no <tt>options</tt> hash is passed or if <tt>:update</tt> is specified, the default is
+    # to render a partial and use the second parameter as the locals hash.
     def render(*args)
       raise "missing controller" unless controller