fixup! fix: Use last zombie trove first in a redemption sequence

liquity · Sep 17, 2024 · 4358aaa · 4358aaa
1 parent 25f8d02
commit 4358aaa
Show file tree

Hide file tree

Showing 2 changed files with 30 additions and 1 deletion.
diff --git a/contracts/src/TroveManager.sol b/contracts/src/TroveManager.sol
@@ -679,9 +679,12 @@ contract TroveManager is LiquityBase, ITroveManager, ITroveEvents {
                 if (newDebt > 0) {
                     lastZombieTroveId = _singleRedemption.troveId;
                 }
+            } else if (newDebt == 0) {
+                // Reset last zombie trove pointer if the previous one was fully redeemed now
+                lastZombieTroveId = 0;
             }
         } else {
-            // Reset last zombie trove pointer if the previous one was fully redeemed now
+            // Reset last zombie trove pointer if the previous one ended up above min debt
             lastZombieTroveId = 0;
         }
     }

diff --git a/contracts/src/test/redemptions.t.sol b/contracts/src/test/redemptions.t.sol
@@ -22,12 +22,14 @@ contract Redemptions is DevTestSetup {
 
         uint256 debt_A = troveManager.getTroveEntireDebt(troveIDs.A);
         uint256 debt_B = troveManager.getTroveEntireDebt(troveIDs.B);
+        /*
         console.log(troveIDs.A, "A id");
         console.log(troveIDs.B, "B id");
         console.log(sortedTroves.contains(troveIDs.B), "B is in list t0");
         console.log(troveManager.getTroveEntireDebt(troveIDs.B), "A debt t0");
         console.log(troveManager.getTroveEntireDebt(troveIDs.B), "B debt t0");
         console.log(sortedTroves.getLast(), "first to redeem t0");
+        */
         uint256 debt_C = troveManager.getTroveEntireDebt(troveIDs.C);
         uint256 debt_D = troveManager.getTroveEntireDebt(troveIDs.D);
 
@@ -369,6 +371,30 @@ contract Redemptions is DevTestSetup {
         assertEq(troveManager.lastZombieTroveId(), 0, "Wrong last zombie trove pointer");
     }
 
+    function testZombieTrovePointerGetsResetIfLastOneIsFullyRedemeed() public {
+        (,, ABCDEF memory troveIDs) = _setupForRedemptionAscendingInterest();
+
+        _redeemAndCreateZombieTrovesAAndB(troveIDs);
+
+        // Check last Zombie trove pointer
+        assertEq(troveManager.lastZombieTroveId(), troveIDs.B, "Wrong last zombie trove pointer before");
+
+        // Get B debt before 2nd redeem
+        uint256 debt_B = troveManager.getTroveEntireDebt(troveIDs.B);
+        assertGt(debt_B, 0, "B debt should be non zero");
+
+        uint256 redeemAmount = debt_B;
+        console2.log("redeem again");
+        console2.log(redeemAmount, "redeemAmount");
+        redeem(E, redeemAmount);
+
+        // Check B is empty now
+        assertEq(troveManager.getTroveEntireDebt(troveIDs.B), 0, "B debt should be zero");
+
+        // Check last Zombie trove pointer
+        assertEq(troveManager.lastZombieTroveId(), 0, "Wrong last zombie trove pointer after");
+    }
+
     function testZombieTrovesCanReceiveRedistGains() public {
         uint256 interestRate_E = 5e16; // 5%
         uint256 troveDebtRequest_E = 2450e18;