v2.2.0: add blackjack with reserved bets and hit/stand/double

1 files changed, 139 insertions, 0 deletions

diff --git a/tests/blackjack.rs b/tests/blackjack.rs
new file mode 100644
index 0000000..79721d3
--- /dev/null
+++ b/tests/blackjack.rs
@@ -0,0 +1,139 @@
+use zagan_bet::blackjack::{
+    card_label, card_value, fresh_shoe, hand_total, is_blackjack, BlackjackState,
+};
+use zagan_bet::server::games::blackjack::BlackjackGame;
+
+fn hand(deck: &[&str], bet: u64) -> zagan_bet::server::games::blackjack::BlackjackHand {
+    let deck = deck.iter().map(|card| card.to_string()).collect();
+    BlackjackGame::with_deck(deck).deal(bet)
+}
+
+#[test]
+fn card_values_and_soft_totals_are_correct() {
+    assert_eq!(card_value("AS"), 11);
+    assert_eq!(card_value("10H"), 10);
+    assert_eq!(card_value("KD"), 10);
+    assert_eq!(card_label("AS"), "A♠");
+    assert_eq!(card_label("10H"), "10♥");
+
+    let cards = |values: &[&str]| values.iter().map(|card| card.to_string()).collect::<Vec<_>>();
+    assert_eq!(hand_total(&cards(&["AS", "10H"])), 21);
+    assert_eq!(hand_total(&cards(&["AS", "9H"])), 20);
+    assert_eq!(hand_total(&cards(&["AS", "AS", "9H"])), 21);
+    assert!(is_blackjack(&cards(&["AS", "KH"])));
+    assert!(!is_blackjack(&cards(&["AS", "9H"])));
+}
+
+#[test]
+fn a_six_deck_shoe_has_312_cards() {
+    let shoe = fresh_shoe();
+    assert_eq!(shoe.len(), 312);
+    assert_eq!(shoe.iter().filter(|card| card.as_str() == "AS").count(), 6);
+}
+
+#[test]
+fn a_natural_blackjack_settles_immediately() {
+    let hand = hand(&["AS", "9D", "KH", "8C"], 10);
+
+    assert!(hand.is_done());
+    assert_eq!(hand.result, "blackjack");
+    assert_eq!(hand.winnings, 25); // 10 + 15
+    assert_eq!(hand.player_total(), 21);
+}
+
+#[test]
+fn a_player_hand_can_hit_to_21() {
+    let mut hand = hand(&["10S", "9D", "6H", "8C", "5D"], 10);
+    assert_eq!(hand.player_total(), 16);
+    assert_eq!(hand.dealer_total(), 17);
+
+    hand.hit().unwrap();
+
+    assert!(hand.is_done());
+    assert_eq!(hand.player_total(), 21);
+    assert_eq!(hand.result, "win");
+    assert_eq!(hand.winnings, 20);
+}
+
+#[test]
+fn hitting_over_21_busts() {
+    let mut hand = hand(&["10S", "9D", "6H", "8C", "KD"], 10);
+    hand.hit().unwrap();
+
+    assert!(hand.is_done());
+    assert_eq!(hand.result, "bust");
+    assert_eq!(hand.winnings, 0);
+}
+
+#[test]
+fn doubling_adds_the_base_bet_and_draws_one_card() {
+    let mut hand = hand(&["5S", "9D", "5H", "8C", "10D"], 10);
+    assert_eq!(hand.player_total(), 10);
+
+    hand.double().unwrap();
+
+    assert_eq!(hand.player.len(), 3);
+    assert_eq!(hand.bet, 20);
+    assert_eq!(hand.player_total(), 20);
+    assert_eq!(hand.result, "win");
+    assert_eq!(hand.winnings, 40);
+}
+
+#[test]
+fn the_dealer_busts_and_the_player_wins() {
+    let mut hand = hand(&["10S", "7H", "8H", "9C", "10H"], 10);
+    assert_eq!(hand.player_total(), 18);
+    assert_eq!(hand.dealer_total(), 16);
+
+    hand.stand();
+
+    assert_eq!(hand.dealer_total(), 26);
+    assert_eq!(hand.result, "win");
+    assert_eq!(hand.winnings, 20);
+}
+
+#[test]
+fn the_dealer_stands_on_soft_17() {
+    let mut hand = hand(&["10S", "AD", "8H", "6C"], 10);
+    assert_eq!(hand.dealer_total(), 17);
+
+    hand.stand();
+
+    assert_eq!(hand.dealer.len(), 2, "dealer must stand on soft 17");
+    assert_eq!(hand.result, "win");
+    assert_eq!(hand.winnings, 20);
+}
+
+#[test]
+fn equal_totals_push() {
+    let mut hand = hand(&["10S", "10D", "8H", "8C"], 10);
+    hand.stand();
+
+    assert_eq!(hand.result, "push");
+    assert_eq!(hand.winnings, 10);
+}
+
+#[test]
+fn dealer_blackjack_wins_unless_player_also_has_it() {
+    let dealer_blackjack = hand(&["10S", "AS", "8H", "KD"], 10);
+    assert_eq!(dealer_blackjack.result, "lose");
+    assert_eq!(dealer_blackjack.winnings, 0);
+
+    let both = hand(&["AS", "AD", "KH", "KC"], 10);
+    assert_eq!(both.result, "push");
+    assert_eq!(both.winnings, 10);
+}
+
+#[test]
+fn the_player_state_hides_the_hole_card() {
+    let hand = hand(&["10S", "9D", "6H", "8C"], 10);
+    let state: BlackjackState = hand.state("session-1", 990);
+
+    assert_eq!(state.phase, "player");
+    assert_eq!(state.dealer, vec!["9D".to_string(), "?".to_string()]);
+    assert_eq!(state.dealer_total, 9);
+    assert_eq!(state.player_total, 16);
+    assert_eq!(state.actions, vec!["hit", "stand", "double"]);
+    assert_eq!(state.bet, 10);
+    assert_eq!(state.balance, 990);
+}