Crystal: Should `XML::Builder#cdata` escape nested `]]>`

[Blacksmoke16]

Currently XML::Builder#cdata happily encodes ]]> within the provided string.

https://play.crystal-lang.org/#/r/90ev

require "xml"

string = XML.build(indent: "  ") do |xml|
  xml.element("data") { xml.cdata "FOO]]>BAR" }
end

string # => <data><![CDATA[FOO]]>BAR]]></data>

This ultimately causes it to generate invalid XML.

The question is, should it internally handle escaping the end sequence, or leave that up to the user to handle?

[jhass]

I'd say it clearly should.