# File lib/rake.rb, line 415
415:     def investigation
416:       result = "------------------------------\n"
417:       result << "Investigating #{name}\n" 
418:       result << "class: #{self.class}\n"
419:       result <<  "task needed: #{needed?}\n"
420:       result <<  "timestamp: #{timestamp}\n"
421:       result << "pre-requisites: \n"
422:       prereqs = @prerequisites.collect {|name| Rake::Task[name]}
423:       prereqs.sort! {|a,b| a.timestamp <=> b.timestamp}
424:       prereqs.each do |p|
425:         result << "--#{p.name} (#{p.timestamp})\n"
426:       end
427:       latest_prereq = @prerequisites.collect{|n| Rake::Task[n].timestamp}.max
428:       result <<  "latest-prerequisite time: #{latest_prereq}\n"
429:       result << "................................\n\n"
430:       return result
431:     end