DRYer specs

something.rb

module Something
  def self.foo a, *args
    a.zip(*args).flatten.select{|e|e}
  end
end

something_spec.rb

require 'minitest/autorun'
require 'something'

describe Something do
  {
    "with 1 array" => [ [1,2,3] ],
    "with 2 arrays" => [ [1,2,3], [4,5,6] ],
    "with more than 2 arrays" => [ [1,2,3], [4,5,6], [7], [8,9] ],
  }.each do |title,data|
  describe title  do
    it "returns all elements" do
      Something.foo(*data).count.must_equal data.reduce(0){|sum,a|sum+a.count}
    do
  end
end