Item1420: DirectedGraphPlugin make search fail on System.InstalledPlugins

The DirectedGraphPlugin makes a search fail on the InstalledPlugins page when the plugin is enabled. This is the start of error message that is generated:

Could not perform search. Error was: Use of uninitialized value $_[1] in string ne at /var/www/fw/core/lib/Foswiki/Plugins/DirectedGraphPlugin.pm line 226. at /usr/share/perl/5.10/CGI/Carp.pm line 356 CGI::Carp::realdie('Use of uninitialized value $_[1] in string ne at /var/www/fw/...') called at /usr/share/perl/5.10/CGI/Carp.pm line 437 CGI::Carp::die('Use of uninitialized value $_[1] in string ne at /var/www/fw/...') called at /var/www/fw/core/lib/Foswiki.pm line 270 Foswiki::__ANON__('Use of uninitialized value $_[1] in string ne at /var/www/fw/...') called at /var/www/fw/core/lib/Foswiki/Plugins/DirectedGraphPlugin.pm line 226

Foswiki::Plugins::DirectedGraphPlugin::commonTagsHandler('Search
    %SEARCHSTRING%

    \x{a}', undef, 'System', 0, 'Foswiki::Meta=HASH(0xa09cb00)') called at /var/www/fw/core/lib/Foswiki/Plugin.pm line 282

The problem is that the "topic" parameter ( $_[1] ) is undef.

-- MichaelTempest - 05 Apr 2009

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Fixed it in the core, which is where the real bug was.

-- CrawfordCurrie - 05 Apr 2009

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Reverted change to the plugin since the root cause was fixed.

-- MichaelTempest - 05 Apr 2009