Re: Starting a script block with

On Fri, 26 Mar 2010 08:14:05 +0100, Ian Hickson <[email protected]> wrote:

On Fri, 26 Mar 2010, Herman Venter wrote:

Thanks, that clarifies things a lot.

Looking closely at the state engine, however, I can only see that </script> will not end the script block provided that it has been preceded by both an

unterminated <!-- and a opening <script> tag.

I don't quite see how this meets the requirements in http://wiki.whatwg.org/wiki/CDATA_Escapes

For example,
  <script><!--
   document.write('<scr'+'ipt></script>');
  //--></script>

Looks to me like it will transition from Script Data Double Escape Start
to Script Data Escaped as soon as the ' following <scr is encountered.

That will prevent entry into Script Data Double Escaped and cause the
scanning to exit the script state once the first </script> tag is seen.

Am I misreading this?

No, I think your understanding is correct. I believe this was the
intention (the wiki page is a bit out of date relative to what ended up
being specced after discussion).

Yeah, it's known that it breaks in the above case (the wiki page lists that case and also another case). However, from the research it only affected on the order of 10 pages out of 425k, while at the same time fixing the rest of the about 1000 pages that were broken with the previous parsing rules.

See http://lists.w3.org/Archives/Public/public-html/2009Oct/0146.html

--
Simon Pieters
Opera Software