244675 - multi level HTML comment tag wrong behaviour , documents not readable

Status: VERIFIED INVALID

(Core :: DOM: HTML Parser, defect)

Description

[Patrick Nomblot]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; fr; rv:1.6) Gecko/20040206 Firefox/0.8
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; fr; rv:1.6) Gecko/20040206 Firefox/0.8

Two or more consecutive opening HTML comment tags (<!-- ) needs one or two
closing HTML comment tags.

HTML coment tags are not re-entrant HTML feature. More than one tag <!--
should only need one closing tag  --> 

If not, rest of HTML doc is not visible on Mozilla

2 opening tags need 2 closing tags
3 opening tags need 1 closing tag
4 opening tags need 2 closing tags
5 opening tags need 1 closing tag
6 opening tags need 2 closing tags
etc...


Reproducible: Always
Steps to Reproduce:
1. create an HTML doc with repeated <!-- tags
2. visualize doc for each given case
3. 

Actual Results:  
2 opening tags need 2 closing tags
3 opening tags need 1 closing tag
4 opening tags need 2 closing tags
5 opening tags need 1 closing tag
6 opening tags need 2 closing tags
etc...


Expected Results:  
1 opening tags need 1 closing tag
2 opening tags need 1 closing tag
3 opening tags need 1 closing tag
4 opening tags need 1 closing tag
5 opening tags need 1 closing tag
6 opening tags need 1 closing tag
etc...

Comment 1

[Patrick Nomblot]

Attachment: This is an HTML test to show the bug, HTML source in green area, result in red area

Comment 2

[Patrick Nomblot]

Comment on attachment 149297 [details]
This is an HTML test to show the bug, HTML source in green area, result in red area

This tag has no levels.

Comment 3

[Boris Zbarsky [:bzbarsky]]

SGML comments are started and stopped by "--".  The '<!' and '>' just signal the
start and end of SGML markup.  Thus:

  <!-- comment -- not comment, but SGML markup -- comment> Still comment

is an unterminated comment.  Please read what the HTML spec has to say about
'--' and comments carefully. 

Note that in quirks mode we will do the sort of broken comment parsing that you
seem to expect.  But your document is claiming to be XHTML, so we parse it per
the standard.