id,summary,reporter,owner,description,type,status,priority,milestone,component,version,severity,resolution,keywords,cc
10490,paragraphs inserted round shortcodes by wpautop not working properly for tag-end-tag paits,alanjohndix,,"The regex returned by get_shortcode_regex() had a back-reference '\[\/\2\]' to match balanced tag-end-tag pairs such as ""[x]text[/x]"".  The regex assumes it will be used 'bare' as a regular expression.  However, wpautop adds extra enclosing brackets to be able to refer to the entire matched tags and content.  This means that the back-reference instead matches the (optional) preceding letter which is usually blank and thus the closing tag does not match properly.

In the case of single tag-end-tag pair, this means that 

   [divtag]
   abc
   [/divtag]

ends up as

   <div class=""mydiv"">
   <p>abc</p>
   <p></div></p>

This gets more complicated when there are internal tags such as:

   [mytag] some [specialsymbol] text [/mytag]

As in some cases the existing .*? for attribute matching chomps everything while it tries to find a '/'.

A simple fix would be to add an optional parameter to get_shortcode_regex($nested=0) and use this to modify the regular expression.  This would give the intended match for the shortcode regex, but in fact makes things worse. Looking at the same source:

   [divtag]
   abc
   [/divtag]

it would generate (assuming [divtag] generates a div):

   <div class=""mydiv""></p>
   <p>abc</p>
   <p></div>

The attached patch addresses this by adding two new functions to shortcodes.php returning regular expressions for matching begin and end tags separately.  wpautop then has two separate preg_replace lines doing the <p> fixes.

At the same time I swopped the .*? for attribute matching to [^\]]*?
I guess slightly slower, but doesn't risk chomping the entire post as an attribute.

Note: Sorry, the end tags above all come out odd, but don't know the TRAC editor so don't know how to tell it to treat them as literals.  I've done a nicely formatted version of the report at:
http://www.alandix.com/blog/2009/07/26/fix-for-wordpress-shortcode-bug/


",defect (bug),closed,normal,,Shortcodes,,normal,duplicate,"shortcodes, wpautop",spathon