1 files changed, 20 insertions, 0 deletions

diff --git a/tests/roulette.rs b/tests/roulette.rs
index 0c5e195..970ab6a 100644
--- a/tests/roulette.rs
+++ b/tests/roulette.rs
@@ -396,3 +396,23 @@ fn rejects_bad_roulette_results() {
     assert!(parse_roulette_response("ROULETTE_RESULT s 1 1 1 17 black nope").is_err());
     assert!(parse_roulette_response("").is_err());
 }
+
+#[test]
+fn chips_can_be_taken_back_one_at_a_time() {
+    let mut bets = Bets::default();
+    bets.add(BetTarget::Straight { number: 17 }, 50);
+    bets.add(BetTarget::Outside { kind: Outside::Red }, 10);
+
+    bets.reduce(&BetTarget::Straight { number: 17 }, 25);
+    assert_eq!(bets.amount_on(&BetTarget::Straight { number: 17 }), 25);
+    assert_eq!(bets.total(), 35);
+
+    // Reducing past zero drops the chip instead of going negative.
+    bets.reduce(&BetTarget::Straight { number: 17 }, 100);
+    assert_eq!(bets.amount_on(&BetTarget::Straight { number: 17 }), 0);
+    assert_eq!(bets.total(), 10);
+
+    // A target with no chip is left alone.
+    bets.reduce(&BetTarget::Dozen { index: 0 }, 25);
+    assert_eq!(bets.total(), 10);
+}