Bug 1961002

ping - you can't break long years running expected behavior with a random update in the middle of a stable release

stripped down reproducer (php cli-script, the passthru shows the installed libxml package update in a different terminal)
look at the disappearing <br> after the "</a" was corrected to "</a>" with the new version
not funny after 6 years in the middle of a stable fedora release

[harry@srv-rhsoft:/downloads]$ cat test.php
#!/usr/bin/php
<?php
$data = "<a href=\"http://localhost/show_content.php?sid=1_3#anchor4\"></a<br>\nTest\n";
echo "------------------------------------------------------------------------------------\n";
passthru("rpm -q libxml2");
echo "\nINPUT:\n";
echo $data;
libxml_use_internal_errors(TRUE);
$doc = new DOMDocument;
$doc->resolveExternals = FALSE;
$doc->preserveWhiteSpace = TRUE;
$doc->strictErrorChecking = FALSE;
$doc->formatOutput = TRUE;
$doc->recover = TRUE;
$doc->validateOnParse = TRUE;
$doc->substituteEntities = FALSE;
$loaded = $doc->loadHTML("<?xml encoding=\"UTF-8\">{$data}", LIBXML_HTML_NODEFDTD);
$body = $doc->getElementsByTagName('body')->item(0);
$data = '';
$fragment = $doc->createDocumentFragment();
while($body->childNodes->length > 0)
{
 $childNode = $body->childNodes->item(0);
 $fragment->appendChild($childNode);
 $data = "{$data}{$doc->saveHTML($childNode)}";
}
echo "\nOUTPUT:\n";
echo $data;
echo "------------------------------------------------------------------------------------\n";
?>



[harry@srv-rhsoft:/downloads]$ php test.php
------------------------------------------------------------------------------------
libxml2-2.9.10-8.fc33.x86_64

INPUT:
<a href="http://localhost/show_content.php?sid=1_3#anchor4"></a<br>
Test

OUTPUT:
<a href="http://localhost/show_content.php?sid=1_3#anchor4"></a><br>
Test
------------------------------------------------------------------------------------



[harry@srv-rhsoft:/downloads]$ php test.php
------------------------------------------------------------------------------------
libxml2-2.9.12-4.fc33.x86_64

INPUT:
<a href="http://localhost/show_content.php?sid=1_3#anchor4"></a<br>
Test

OUTPUT:
<a href="http://localhost/show_content.php?sid=1_3#anchor4"></a>
Test
------------------------------------------------------------------------------------

and it also breaks php.net upstream autotests

FAILED TEST SUMMARY
---------------------------------------------------------------------
Test DOMDocument::loadXML() detects not-well formed XML [ext/dom/tests/DOMDocument_loadXML_error1.phpt]
Test DOMDocument::load() detects not-well formed XML [ext/dom/tests/DOMDocument_load_error1.phpt]

wine applications or games that use libxml2-2.9.12-4.fc33.x86_64 are also affected.

Typical wine output before application crashes (in this case Colonization IV)

regexp error : failed to compile: Improper quantifier
regexp error : failed to compile: xmlFAParseRegExp: extra characters
0104:err:msxml:Schema_parse error code 1756: Element '{http://www.w3.org/2001/XMLSchema}pattern': The value '([0-9]{,14})([.][0-9]{,4})?' of the facet 'pattern' is not a valid regular expression.
regexp error : failed to compile: Improper quantifier
regexp error : failed to compile: xmlFAParseAtom: expecting ')'
regexp error : failed to compile: xmlFAParseRegExp: extra characters
0104:err:msxml:Schema_parse error code 1756: Element '{http://www.w3.org/2001/XMLSchema}pattern': The value '([0-9A-Fa-f]{4})([-]{,1}[0-9A-Fa-f]{4})*' of the facet 'pattern' is not a valid regular expression.
0104:fixme:msxml:cache_entry_from_xdr_doc failed to parse doc
0104:fixme:msxml:domdoc_putref_schemas (0x1294c30)->(0x11def00 {VT_DISPATCH: 0x12913a4}): semi-stub

By downgrading to libxml2-2.9.10-8.fc33.x86_64 wine does not complain anymore and all works fine.

Latest rawhide version of libxml2 is also broken (libxml2-2.9.12-5.fc35.x86_64), shows same problem as libxml2-2.9.12-4.fc33.x86_64.

sadly nobody gives a shit - so i adopted my autotests and decided to live with the fallout in the hope nobody will fix it now to prevent a endless back and forth

in a professional world people would write the slightest autotests for their shit, won't happen - i gave up after 20 years in that business full of shit and just deal with the outfull! why? because i am too old wo wait months for every little piece of shit

This message is a reminder that Fedora 33 is nearing its end of life.
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version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

This message is a reminder that Fedora 33 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora 33 on 2021-11-30.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
Fedora 'version' of '33'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 33 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

This message is a reminder that Fedora 33 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora 33 on 2021-11-30.
It is Fedora's policy to close all bug reports from releases that are no longer
maintained. At that time this bug will be closed as EOL if it remains open with a
Fedora 'version' of '33'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 33 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Fedora 33 changed to end-of-life (EOL) status on 2021-11-30. Fedora 33 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

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