1 files changed, 75 insertions, 0 deletions
diff --git a/actionview/lib/action_view/helpers/javascript_helper.rb b/actionview/lib/action_view/helpers/javascript_helper.rb
new file mode 100644
index 0000000000..e475d5b018
--- /dev/null
+++ b/actionview/lib/action_view/helpers/javascript_helper.rb
@@ -0,0 +1,75 @@
+require 'action_view/helpers/tag_helper'
+
+module ActionView
+  module Helpers
+    module JavaScriptHelper
+      JS_ESCAPE_MAP = {
+        '\\'    => '\\\\',
+        '</'    => '<\/',
+        "\r\n"  => '\n',
+        "\n"    => '\n',
+        "\r"    => '\n',
+        '"'     => '\\"',
+        "'"     => "\\'"
+      }
+
+      JS_ESCAPE_MAP["\342\200\250".force_encoding(Encoding::UTF_8).encode!] = '&#x2028;'
+      JS_ESCAPE_MAP["\342\200\251".force_encoding(Encoding::UTF_8).encode!] = '&#x2029;'
+
+      # Escapes carriage returns and single and double quotes for JavaScript segments.
+      #
+      # Also available through the alias j(). This is particularly helpful in JavaScript
+      # responses, like:
+      #
+      #   $('some_element').replaceWith('<%=j render 'some/element_template' %>');
+      def escape_javascript(javascript)
+        if javascript
+          result = javascript.gsub(/(\\|<\/|\r\n|\342\200\250|\342\200\251|[\n\r"'])/u) {|match| JS_ESCAPE_MAP[match] }
+          javascript.html_safe? ? result.html_safe : result
+        else
+          ''
+        end
+      end
+
+      alias_method :j, :escape_javascript
+
+      # Returns a JavaScript tag with the +content+ inside. Example:
+      #   javascript_tag "alert('All is good')"
+      #
+      # Returns:
+      #   <script>
+      #   //<![CDATA[
+      #   alert('All is good')
+      #   //]]>
+      #   </script>
+      #
+      # +html_options+ may be a hash of attributes for the <tt>\<script></tt>
+      # tag.
+      #
+      #   javascript_tag "alert('All is good')", defer: 'defer'
+      #   # => <script defer="defer">alert('All is good')</script>
+      #
+      # Instead of passing the content as an argument, you can also use a block
+      # in which case, you pass your +html_options+ as the first parameter.
+      #
+      #   <%= javascript_tag defer: 'defer' do -%>
+      #     alert('All is good')
+      #   <% end -%>
+      def javascript_tag(content_or_options_with_block = nil, html_options = {}, &block)
+        content =
+          if block_given?
+            html_options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
+            capture(&block)
+          else
+            content_or_options_with_block
+          end
+
+        content_tag(:script, javascript_cdata_section(content), html_options)
+      end
+
+      def javascript_cdata_section(content) #:nodoc:
+        "\n//#{cdata_section("\n#{content}\n//")}\n".html_safe
+      end
+    end
+  end
+end