defmodule MinmaxlistTest do
  use ExUnit.Case
  doctest Minmaxlist


  test "min list by" do
    assert Minmaxlist.min_list_by(["a", "b", "aa", "bb", "bbb", "aaa"], fn(x) -> String.length(x) end) == ["a", "b"]
    assert Minmaxlist.min_list_by([], fn(x) -> String.length(x) end) == []
  end

  test "max list by" do
    assert Minmaxlist.max_list_by(["a", "b", "aa", "bb", "bbb", "aaa"], fn(x) -> String.length(x) end) == ["bbb", "aaa"]
    assert Minmaxlist.max_list_by([], fn(x) -> String.length(x) end) == []
  end

  test "min max list by" do
    assert Minmaxlist.min_max_list_by(["a", "b", "aa", "bb", "bbb", "aaa"], fn(x) -> String.length(x) end) == {["a", "b"], ["bbb", "aaa"]}
    assert Minmaxlist.min_max_list_by([], fn(x) -> String.length(x) end) == {[], []}
  end

  test "README examples" do
    import Minmaxlist
    dataset = [
      %{name: "A", age: 24, income: 4000},
      %{name: "B", age: 22, income: 3300},
      %{name: "C", age: 22, income: 2800},
      %{name: "D", age: 25, income: 5000},
      %{name: "E", age: 22, income: 3300},
      %{name: "F", age: 25, income: 5500},
      %{name: "G", age: 24, income: 4500},
    ]

    result = dataset |> min_list_by(&(&1.age)) |> max_list_by(&(&1.income))
    assert result == [%{name: "B", age: 22, income: 3300}, %{name: "E", age: 22, income: 3300}]

    result = dataset |> min_max_list_by(&(&1.age))
    assert result == {
      [%{name: "B", age: 22, income: 3300}, %{name: "C", age: 22, income: 2800}, %{name: "E", age: 22, income: 3300}],
      [%{name: "D", age: 25, income: 5000}, %{name: "F", age: 25, income: 5500}]
    }
  end
end