Word count in Elixir

word_count.exs

defmodule WordCount do
  def count(phrase) do
    String.split(phrase)
        |> Enum.reduce(%{}, fn(word, map) ->
             Map.update(map, word, 1, &(&1 + 1))
           end)
        |> Enum.to_list()
  end
end

ExUnit.start

defmodule WordCountTest do

  use ExUnit.Case, async: true

  test "no words no count" do
    result = WordCount.count("")
    assert [] == result
  end

  test "three words 3 count" do
    [{_,count}|_] = WordCount.count("hello hello hello")
    assert count == 3
  end

  test "multiple counts" do
    result = WordCount.count("this is fun this is fun this is fun")
    assert length(result) == 3
    [{_, count}| _] = result
    assert count == 3
  end
end