Introduce `render :html` for render HTML string

This is an option for to HTML content with a content type of
`text/html`. This rendering option calls `ERB::Util.html_escape`
internally to escape unsafe HTML string, so you will have to mark your
string as html safe if you have any HTML tag in it.

Please see #12374 for more detail.

1 files changed, 34 insertions, 0 deletions

diff --git a/actionview/lib/action_view/template/html.rb b/actionview/lib/action_view/template/html.rb
new file mode 100644
index 0000000000..282da1a8a2
--- /dev/null
+++ b/actionview/lib/action_view/template/html.rb
@@ -0,0 +1,34 @@
+module ActionView #:nodoc:
+  # = Action View HTML Template
+  class Template
+    class HTML #:nodoc:
+      attr_accessor :type
+
+      def initialize(string, type = nil)
+        @string = string.to_s
+        @type   = Types[type] || type if type
+        @type ||= Types[:html]
+      end
+
+      def identifier
+        'html template'
+      end
+
+      def inspect
+        'html template'
+      end
+
+      def to_str
+        ERB::Util.h(@string)
+      end
+
+      def render(*args)
+        to_str
+      end
+
+      def formats
+        [@type.to_sym]
+      end
+    end
+  end
+end