# File lib/rake.rb, line 690
690:     def investigation
691:       result = "------------------------------\n"
692:       result << "Investigating #{name}\n"
693:       result << "class: #{self.class}\n"
694:       result <<  "task needed: #{needed?}\n"
695:       result <<  "timestamp: #{timestamp}\n"
696:       result << "pre-requisites: \n"
697:       prereqs = @prerequisites.collect {|name| application[name]}
698:       prereqs.sort! {|a,b| a.timestamp <=> b.timestamp}
699:       prereqs.each do |p|
700:         result << "--#{p.name} (#{p.timestamp})\n"
701:       end
702:       latest_prereq = @prerequisites.collect{|n| application[n].timestamp}.max
703:       result <<  "latest-prerequisite time: #{latest_prereq}\n"
704:       result << "................................\n\n"
705:       return result
706:     end