public void Winners_Rating_Should_Increase(Rating winner, Rating loser)
{
// Arrange
var trueSkillEngine = new TwoPlayerTrueSkillEngine();
var winnerInitialValue = new Rating(winner.Mean, winner.StandardDeviation);
// Act
trueSkillEngine.UpdateRatings(winner, loser);
// Assert
winner.Mean.Should().BeGreaterThan(winnerInitialValue.Mean, "The winner's mean should have increased due to winning a match");
winner.StandardDeviation.Should().BeLessThan(winnerInitialValue.StandardDeviation, "The winner's standard deviation should have decreased due to having played more matches");
}
public void Losers_Rating_Should_Decrease(Rating winner, Rating loser)
{
// Arrange
var trueSkillEngine = new TwoPlayerTrueSkillEngine();
var loserInitialValue = new Rating(loser.Mean, loser.StandardDeviation);
// Act
trueSkillEngine.UpdateRatings(winner, loser);
// Assert
loser.Mean.Should().BeLessThan(loserInitialValue.Mean, "The loser's mean should have decreased due to losing a match.");
loser.StandardDeviation.Should().BeLessThan(loserInitialValue.StandardDeviation, "The loser's standard deviation should have decreased due to having played more matches.");
}
public void Should_Update_Both_Ratings(Rating winner, Rating loser)
{
// Arrange
var trueSkillEngine = new TwoPlayerTrueSkillEngine();
var winnerInitialValue = new Rating(winner.Mean, winner.StandardDeviation);
var loserInitialValue = new Rating(loser.Mean, loser.StandardDeviation);
// Act
trueSkillEngine.UpdateRatings(winner, loser);
// Assert
winner.Should().NotBeEquivalentTo(winnerInitialValue, "Update ratings should update both the winner's mean and standard deviation");
loser.Should().NotBeEquivalentTo(loserInitialValue, "Update ratings should update both the loser's mean and standard deviation");
}