glicko-elixir/test/player_test.exs

defmodule Glicko.PlayerTest do
	use ExUnit.Case

	alias Glicko.Player

	doctest Player

	@valid_v1_base %Player{version: :v1, rating: 1.0, rating_deviation: 2.0, volatility: nil}
	@valid_v2_base %Player{version: :v2, rating: 1.0, rating_deviation: 2.0, volatility: 3.0}

	test "create v1" do
		assert @valid_v1_base == Player.new_v1([rating: 1.0, rating_deviation: 2.0])
	end

	test "create v2" do
		assert @valid_v2_base == Player.new_v2([rating: 1.0, rating_deviation: 2.0, volatility: 3.0])
	end

	test "convert player v1 -> v2" do
		assert %Player{
			version: :v2,
			rating: Player.scale_rating_to(1.0, :v2),
			rating_deviation: Player.scale_rating_deviation_to(2.0, :v2),
			volatility: 3.0,
		} == Player.to_v2(@valid_v1_base, 3.0)
	end

	test "convert player v2 -> v1" do
		assert %Player{
			version: :v1,
			rating: Player.scale_rating_to(1.0, :v1),
			rating_deviation: Player.scale_rating_deviation_to(2.0, :v1),
			volatility: nil,
		} == Player.to_v1(@valid_v2_base)
	end

	test "convert player v1 -> v1" do
		assert @valid_v1_base == Player.to_v1(@valid_v1_base)
	end

	test "convert player v2 -> v2" do
		assert @valid_v2_base == Player.to_v2(@valid_v2_base)
	end

	test "scale rating v1 -> v2" do
		assert_in_delta Player.scale_rating_to(1673.7178, :v2), 1.0, 0.1
	end

	test "scale rating v2 -> v1" do
		assert_in_delta Player.scale_rating_to(1.0, :v1), 1673.7178, 0.1
	end

	test "scale rating deviation v1 -> v2" do
		assert_in_delta Player.scale_rating_deviation_to(173.7178, :v2), 1.0, 0.1
	end

	test "scale rating deviation v2 -> v1" do
		assert_in_delta Player.scale_rating_deviation_to(1.0, :v1), 173.7178, 0.1
	end

	test "rating interval" do
		assert {rating_low, rating_high} =
			[rating: 1850, rating_deviation: 50]
			|> Player.new_v2
			|> Player.rating_interval

		assert_in_delta rating_low, 1750, 0.1
		assert_in_delta rating_high, 1950, 0.1
	end
end