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.

5 files changed, 41 insertions, 1 deletions

diff --git a/actionview/lib/action_view/helpers/rendering_helper.rb b/actionview/lib/action_view/helpers/rendering_helper.rb
index 4eae80cd93..15b88bcda6 100644
--- a/actionview/lib/action_view/helpers/rendering_helper.rb
+++ b/actionview/lib/action_view/helpers/rendering_helper.rb
@@ -14,6 +14,9 @@ module ActionView
       # * <tt>:text</tt> - Renders the text passed in out.
       # * <tt>:plain</tt> - Renders the text passed in out. Setting the content
       # type as <tt>text/plain</tt>.
+      # * <tt>:html</tt> - Renders the html safe string passed in out, otherwise
+      # performs html escape on the string first. Setting the content type as
+      # <tt>text/html</tt>.
       # * <tt>:body</tt> - Renders the text passed in, and does not set content
       # type in the response.
       #
diff --git a/actionview/lib/action_view/layouts.rb b/actionview/lib/action_view/layouts.rb
index 3f049e838a..9ee05bd816 100644
--- a/actionview/lib/action_view/layouts.rb
+++ b/actionview/lib/action_view/layouts.rb
@@ -420,7 +420,7 @@ module ActionView
     end
 
     def _include_layout?(options)
-      (options.keys & [:body, :text, :plain, :inline, :partial]).empty? || options.key?(:layout)
+      (options.keys & [:body, :text, :plain, :html, :inline, :partial]).empty? || options.key?(:layout)
     end
   end
 end
diff --git a/actionview/lib/action_view/renderer/template_renderer.rb b/actionview/lib/action_view/renderer/template_renderer.rb
index ba946b230a..be17097428 100644
--- a/actionview/lib/action_view/renderer/template_renderer.rb
+++ b/actionview/lib/action_view/renderer/template_renderer.rb
@@ -27,6 +27,8 @@ module ActionView
         Template::Text.new(options[:text], formats.first)
       elsif options.key?(:plain)
         Template::Text.new(options[:plain])
+      elsif options.key?(:html)
+        Template::HTML.new(options[:html], formats.first)
       elsif options.key?(:file)
         with_fallbacks { find_template(options[:file], nil, false, keys, @details) }
       elsif options.key?(:inline)
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index 9b0619f1aa..961a969b6e 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -90,6 +90,7 @@ module ActionView
     eager_autoload do
       autoload :Error
       autoload :Handlers
+      autoload :HTML
       autoload :Text
       autoload :Types
     end
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