The problem: given a list of strings, produce a list where sequential non-empty strings are concatenate

glom.rb

require "test/unit"


class GlomTest < Test::Unit::TestCase

  def glom(l)
    l.inject([""]) do |r,x|
      r << "" if x.empty?
      r.last << x 
      r
    end.reject{|a| a.empty?}
  end
  def test_concatinate_elements_when_list_elements_have_no_empty_between
    l = ["a", "b", "c"]
    assert_equal ["abc"], glom(l)
  end
  def test_donot_concatinate_elements_when_they_have_empty_between
    l = ["a", "b", "", "c"]
    assert_equal(["ab", "c"], glom(l))

    i = ["a", "", "", "c"]
    assert_equal(["a", "c"], glom(i))
  end
end