Rake task to list the class and names of fabricators defined via the Fabrication gem. Use CLASS and FABRICATOR to filter. Now part of fabrication gem: https://github.com/paulelliott/fabrication/issues/187

fabricators.rake

# https://gist.github.com/sshaw/6259749
#
# As of 2.9.4, this is part of the fabrication gem (less env vars)
# https://github.com/paulelliott/fabrication/blob/master/lib/tasks/defined_fabricators.rake

desc "List fabricators, use CLASS and FABRICATOR to filter"
task :fabricators => :environment do
  Fabrication::Support.find_definitions if Fabrication.manager.empty?
 
  if Fabrication.manager.schematics.none?
    puts "No fabricators found"
    next
  end
 
  groups = Fabrication.manager.schematics.group_by { |name, fabdef| fabdef.klass.name }

  if ENV["CLASS"]
    re = Regexp.new(ENV["CLASS"])
    groups.reject! { |klass, _| klass !~ re } 
  end

  if ENV["FABRICATOR"]
    re = Regexp.new(ENV["FABRICATOR"])
    groups.each do |_, set| 
      set.reject! { |fabdef| fabdef.first.to_s !~ re }
    end

    groups.reject! { |_, set| set.empty? }
  end

  fabricators = {}
  groups.sort_by { |klass, _| klass }.each do |klass, groups|
    fabricators[klass] = groups.map(&:first).sort.join(", ")
  end
  
  class_width = fabricators.keys.max_by { |v| v.size }.size + 3 # padding
  names_width = fabricators.values.max_by { |v| v.size }.size
  say = lambda do |f1, f2|
    printf "%-#{class_width}s%-#{names_width}s\n", f1, f2
  end
    
  say["Class", "Fabricator"]
  puts "-" * (names_width + class_width)
  fabricators.each { |klass, names| say[klass,names] }
end

Output looks like this:

Class    Fabricator   
----------------------
Animal   animal, beast
Person   person