giveaway not being random

[kiki0124]

So if someone with admin role enters a giveaway they have higher chance to win than someone without admin role, from my testing I had about 5 giveaways, each with around 25 participants, 3 admins, 1 winner each giveaway, in 3 of those giveaway one of the people with admin roles won.

[MichailiK]

In the code, the winner of a giveaway is determined here:

GiveawayBot/src/main/java/com/jagrosh/giveawaybot/GiveawayManager.java

Line 138 in 3e12edf

List<CachedUser> winners = GiveawayUtil.selectWinners(all, giveaway.getWinners());

The selectWinners function calls randDouble:

GiveawayBot/src/main/java/com/jagrosh/giveawaybot/util/GiveawayUtil.java

Line 54 in 3e12edf

winlist.add(pullist.remove((int)(randDouble() * pullist.size())));

randDouble uses java.security.SecureRandom to generate a (cryptographically secure) random number.

GiveawayBot/src/main/java/com/jagrosh/giveawaybot/util/GiveawayUtil.java

Lines 36 to 41 in 3e12edf

	private static final SecureRandom random = new SecureRandom();
	private static synchronized double randDouble()
	{
	return random.nextDouble();
	}

Every user has 1 entry, and a random entry will be picked based on the random number generated by SecureRandom. Additionally, there doesn't seem to be any logic adding more entries to a user, or otherwise favoring people.

It seems unlikely to me that GiveawayBot is rigged in any way, may it be through favoring admins, or anything else.