@Test
public void testGetPartnerOf() {
Players players = new Players();
Player player1Team1 = new Player(null);
players.playerJoined(player1Team1);
Player player2Team1 = new Player(null);
players.playerJoined(player2Team1);
Player player1Team2 = new Player(null);
players.playerJoined(player1Team2);
Player player2Team2 = new Player(null);
players.playerJoined(player2Team2);
assertEquals(player2Team1, players.getPartnerOf(player1Team1));
assertEquals(player1Team1, players.getPartnerOf(player2Team1));
assertEquals(player2Team2, players.getPartnerOf(player1Team2));
assertEquals(player1Team2, players.getPartnerOf(player2Team2));
}
