fix(cancel_refund): zero entry.net and decrement market totals on refund

prediction_market/src/lib.rs

@@ -642,7 +642,7 @@ impl PredictionMarketContract {
     pub fn cancel_refund(env: Env, user: Address, market_id: u64) -> Result<i128, MarketError> {
         user.require_auth();
 
-        let market = Self::load_market(&env, market_id)?;
+        let mut market = Self::load_market(&env, market_id)?;
         if !market.cancelled {
             return Err(MarketError::MarketNotCancelled);
         }
@@ -660,8 +660,24 @@ impl PredictionMarketContract {
         }
 
         let gross = entry.gross;
-        entry.gross = 0; // idempotency guard
+        let net = entry.net;
+        // Issue #58: zero both gross (idempotency guard) and net so that
+        // get_bet no longer reports a staked amount after the refund.
+        entry.gross = 0;
+        entry.net = 0;
         env.storage().persistent().set(&bet_key, &entry);
+
+        // Issue #58: decrement market totals so total_yes/total_no reflect
+        // that this bet has been refunded. BetEntry already carries is_yes
+        // and net, so no storage-model change is required.
+        let mkt_key = DataKey::Market(market_id);
+        if entry.is_yes {
+            market.total_yes = market.total_yes.saturating_sub(net);
+        } else {
+            market.total_no = market.total_no.saturating_sub(net);
+        }
+        env.storage().persistent().set(&mkt_key, &market);
+
         // Read-time TTL refresh (issue #9): a refund must not be able to observe
         // an expired bet/market record — keep both alive so a user who returns
         // late to a cancelled market can still pull their refund.
@@ -670,7 +686,7 @@ impl PredictionMarketContract {
             .extend_ttl(&bet_key, TTL_BUMP, TTL_HIGH);
         env.storage()
             .persistent()
-            .extend_ttl(&DataKey::Market(market_id), TTL_BUMP, TTL_HIGH);
+            .extend_ttl(&mkt_key, TTL_BUMP, TTL_HIGH);
 
         let cfg: Config = env.storage().instance().get(&DataKey::Cfg).unwrap();
         token::Client::new(&env, &cfg.xlm_sac).transfer(

prediction_market/src/tests.rs

@@ -464,6 +464,52 @@ fn test_cancel_refund_double_claim_rejected() {
     t.client.cancel_refund(&user, &id); // should fail: NoBetFound (gross zeroed)
 }
 
+// ── Issue #58: cancel_refund zeroes net and decrements market totals ─────────
+
+#[test]
+fn test_cancel_refund_clears_net_and_market_totals() {
+    let t = setup();
+    let id = create_test_market(&t);
+    let alice = Address::generate(&t.env);
+    let bob = Address::generate(&t.env);
+    fund_user(&t, &alice, 200_0000000);
+    fund_user(&t, &bob, 200_0000000);
+
+    // Alice bets YES 100 XLM → net = 100 * 9800/10000 = 98 XLM
+    // Bob   bets NO  50 XLM  → net = 50  * 9800/10000 = 49 XLM
+    t.client.place_bet(&alice, &id, &true, &100_0000000_i128);
+    t.client.place_bet(&bob, &id, &false, &50_0000000_i128);
+
+    let market_before = t.client.get_market(&id);
+    assert_eq!(market_before.total_yes, 98_0000000);
+    assert_eq!(market_before.total_no, 49_0000000);
+
+    // Confirm get_bet reports staked net before cancel
+    let alice_bet_before = t.client.get_bet(&id, &alice);
+    assert_eq!(alice_bet_before.amount, 98_0000000);
+
+    // Cancel the market then refund both bettors
+    t.client.cancel_market(&t.admin, &id);
+    t.client.cancel_refund(&alice, &id);
+    t.client.cancel_refund(&bob, &id);
+
+    // Issue #58 fix: get_bet must return amount == 0 after refund
+    let alice_bet_after = t.client.get_bet(&id, &alice);
+    assert_eq!(alice_bet_after.amount, 0, "net should be zeroed after cancel_refund");
+
+    let bob_bet_after = t.client.get_bet(&id, &bob);
+    assert_eq!(bob_bet_after.amount, 0, "net should be zeroed after cancel_refund");
+
+    // Issue #58 fix: market totals must be decremented to 0 after all refunds
+    let market_after = t.client.get_market(&id);
+    assert_eq!(market_after.total_yes, 0, "total_yes should be 0 after alice's refund");
+    assert_eq!(market_after.total_no, 0, "total_no should be 0 after bob's refund");
+
+    // Gross is still zeroed (idempotency guard unchanged)
+    assert_eq!(t.client.get_bet_gross(&id, &alice), 0);
+    assert_eq!(t.client.get_bet_gross(&id, &bob), 0);
+}
+
 // ── 19. cancel_refund on non-cancelled market rejected ────────────────────────
 
 #[test]