Fix the coupon-closure review findings; keep zero-supply bonds closable

contracts/docs/contracts-reference.md

@@ -124,8 +124,6 @@ Key functions:
   then runs DvP settlement for each allocation.
 - `cancelAuction(isin)`:
   cancels an active auction and reduces the reserved offering accordingly.
-- `withdrawFailedIssuance(isin)`:
-  recovers unsold or failed-to-settle bonds still held by the manager contract.
 - `payCoupon(isin, holders)`:
   pays the next coupon to the provided holder list and advances coupon state.
   On the final period it also repays principal, burns every unit (unsold units

contracts/docs/natspec/src/src/common/Errors.sol/library.Errors.md

@@ -273,12 +273,6 @@ error BondDoesNotExist(string isin);
 error IncorrectBondState(string isin, bool expected);
 ```
 
-### NoFailedIssuance
-
-```solidity
-error NoFailedIssuance();
-```
-
 ### GovReserveAddressZero
 
 ```solidity
@@ -321,6 +315,12 @@ error AllCouponsPaid(string isin);
 error CouponPaymentBalanceMismatch(string isin, uint256 processedBalance, uint256 totalSupply);
 ```
 
+### DuplicateHolder
+
+```solidity
+error DuplicateHolder(string isin, address holder);
+```
+
 ### BondAlreadyDisabled
 
 ```solidity

contracts/docs/natspec/src/src/norges-bank/BondManager.sol/contract.BondManager.md

@@ -402,21 +402,6 @@ function getSealedBids(string calldata _isin) external view returns (IBondAuctio
 |`<none>`|`IBondAuction.Bid[]`|bids Array of sealed bids.|
 
 
-### withdrawFailedIssuance
-
-Allows the issuer to recover bonds that failed to settle during DVP.
-
-
-```solidity
-function withdrawFailedIssuance(string calldata _isin) external onlyRole(Roles.BOND_MANAGER_ROLE);
-```
-**Parameters**
-
-|Name|Type|Description|
-|----|----|-----------|
-|`_isin`|`string`|Target ISIN with failed issuance.|
-
-
 ### payCoupon
 
 Pay the next coupon to every holder; the final coupon also repays principal and closes the bond.

contracts/docs/natspec/src/src/norges-bank/interfaces/IBondManager.sol/interface.IBondManager.md

@@ -81,6 +81,24 @@ event BondBuybackComplete(bytes32 indexed id, string isin, uint256 total);
 event CouponPaid(string indexed isin, address indexed holder, uint256 paymentAmount, uint256 paymentNumber);
 ```
 
+### CouponPeriodPaid
+
+Emitted once per coupon period after the payment count advances, whether or not any
+holder received cash (units held by the manager earn nothing).
+
+```solidity
+event CouponPeriodPaid(string indexed isin, uint256 paymentNumber, uint256 holdersPaid, uint256 couponPaid);
+```
+
+**Parameters**
+
+|Name|Type|Description|
+|----|----|-----------|
+|`isin`|`string`|ISIN of the bond.|
+|`paymentNumber`|`uint256`|1-based period that was just paid.|
+|`holdersPaid`|`uint256`|Number of holders that received a coupon this period.|
+|`couponPaid`|`uint256`|Total coupon paid this period in WNOK.|
+
 ### BondRedeemed
 
 ```solidity

contracts/script/private-bank/08_TbdSetup.s.sol

@@ -62,6 +62,12 @@ contract TbdSetupScript is RegistryScript {
 
         /// @notice Add CSD to DNB allowlist
         _csdSetup(tbdDnb, dnb.key, vm.addr(vm.envUint("PK_CSD")));
+
+        /// @notice Allow both dealer accounts to hold TBD Nordea (Banking page demos)
+        vm.startBroadcast(nordea.key);
+        tbdNordea.add(nordea.addr);
+        tbdNordea.add(dnb.addr);
+        vm.stopBroadcast();
     }
 
     // internal function to set up investors

contracts/src/common/Errors.sol

@@ -62,14 +62,14 @@ library Errors {
     error BondUnitNominalZero();
     error BondDoesNotExist(string isin);
     error IncorrectBondState(string isin, bool expected);
-    error NoFailedIssuance();
     error GovReserveAddressZero();
     error RedemptionIncomplete(string _isin, uint256 remaining);
     error BuybackExceedsSupply(string isin, uint256 buybackSize, uint256 currentSupply);
     error BuybackOfferingZero(string isin);
     error CouponNotReady(string isin, uint256 nextPaymentTime, uint256 currentTime);
     error AllCouponsPaid(string isin);
     error CouponPaymentBalanceMismatch(string isin, uint256 processedBalance, uint256 totalSupply);
+    error DuplicateHolder(string isin, address holder);
     error BondAlreadyDisabled(string isin);
     error BondNotEmpty(string isin, uint256 supply);
     error BondHasFinalisedAuction(string isin, bytes32 auctionId);

contracts/src/norges-bank/BondManager.sol

@@ -19,6 +19,27 @@ import {Roles} from "@common/Roles.sol";
 contract BondManager is IBondManager, AccessControl {
     uint256 private constant PERCENTAGE_PRECISION = 10000; // bps precision (e.g., 425 = 4.25%)
 
+    /**
+     * @dev Running totals of one coupon period, in units (processed, unsold) and WNOK (coupon, principal).
+     */
+    struct PayoutTotals {
+        uint256 processed;
+        uint256 unsold;
+        uint256 holdersPaid;
+        uint256 coupon;
+        uint256 principal;
+    }
+
+    /**
+     * @dev Parameters of the coupon period being paid.
+     */
+    struct Period {
+        bytes32 partition;
+        uint256 paymentPerBond;
+        uint256 paymentNumber;
+        bool finalPeriod;
+    }
+
     string public name;
 
     /**
@@ -467,22 +488,6 @@ contract BondManager is IBondManager, AccessControl {
         return BOND_AUCTION.getSealedBids(auctionId);
     }
 
-    /**
-     * @notice Allows the issuer to recover bonds that failed to settle during DVP.
-     * @param _isin Target ISIN with failed issuance.
-     */
-    function withdrawFailedIssuance(string calldata _isin) external onlyRole(Roles.BOND_MANAGER_ROLE) {
-        bytes32 partition = BOND_TOKEN.isinToPartition(_isin);
-        uint256 failedIssuance = BOND_TOKEN.balanceOfByPartition(partition, address(this));
-
-        if (failedIssuance == 0) revert Errors.NoFailedIssuance();
-
-        bytes32 returnedPartition = BOND_TOKEN.transferByPartition(partition, msg.sender, failedIssuance, "");
-        if (returnedPartition != partition) {
-            revert Errors.SettlementFailure(uint8(IBondDvP.FailureReason.Security), "partition mismatch");
-        }
-    }
-
     /**
      * @notice Pay the next coupon to every holder; the final coupon also repays principal and closes the bond.
      * @param _isin ISIN string
@@ -543,6 +548,7 @@ contract BondManager is IBondManager, AccessControl {
         }
 
         BOND_TOKEN.updateCouponPayment(_isin, block.timestamp, paymentNumber);
+        emit CouponPeriodPaid(_isin, paymentNumber, totals.holdersPaid, totals.coupon);
 
         if (finalPeriod) {
             if (totals.unsold > 0) {
@@ -556,26 +562,6 @@ contract BondManager is IBondManager, AccessControl {
         }
     }
 
-    /**
-     * @dev Running totals of one coupon period, in units (processed, unsold) and WNOK (coupon, principal).
-     */
-    struct PayoutTotals {
-        uint256 processed;
-        uint256 unsold;
-        uint256 coupon;
-        uint256 principal;
-    }
-
-    /**
-     * @dev Parameters of the coupon period being paid.
-     */
-    struct Period {
-        bytes32 partition;
-        uint256 paymentPerBond;
-        uint256 paymentNumber;
-        bool finalPeriod;
-    }
-
     /**
      * @dev Pays every listed holder for one period. Units held by this contract were never sold:
      *      they are counted as unsold and receive nothing.
@@ -585,6 +571,13 @@ contract BondManager is IBondManager, AccessControl {
         returns (PayoutTotals memory totals)
     {
         for (uint256 i = 0; i < _holders.length; i++) {
+            // A repeated address would be paid twice while the coverage check still passes
+            // if another holder were omitted, so reject duplicates outright.
+            for (uint256 j = 0; j < i; j++) {
+                if (_holders[j] == _holders[i]) {
+                    revert Errors.DuplicateHolder(_isin, _holders[i]);
+                }
+            }
             uint256 balance = BOND_TOKEN.balanceOfByPartition(_p.partition, _holders[i]);
             if (balance == 0) {
                 continue;
@@ -595,6 +588,7 @@ contract BondManager is IBondManager, AccessControl {
             }
             (uint256 couponAmount, uint256 principal) = _payHolder(_isin, _holders[i], balance, _p);
             totals.processed += balance;
+            totals.holdersPaid += 1;
             totals.coupon += couponAmount;
             totals.principal += principal;
         }

contracts/src/norges-bank/interfaces/IBondManager.sol

@@ -26,6 +26,16 @@ interface IBondManager {
     // Coupon payment event (one per holder per period)
     event CouponPaid(string indexed isin, address indexed holder, uint256 paymentAmount, uint256 paymentNumber);
 
+    /**
+     * @notice Emitted once per coupon period after the payment count advances, whether or not any
+     *         holder received cash (units held by the manager earn nothing).
+     * @param isin ISIN of the bond.
+     * @param paymentNumber 1-based period that was just paid.
+     * @param holdersPaid Number of holders that received a coupon this period.
+     * @param couponPaid Total coupon paid this period in WNOK.
+     */
+    event CouponPeriodPaid(string indexed isin, uint256 paymentNumber, uint256 holdersPaid, uint256 couponPaid);
+
     // Principal repayment event (one per holder, final period only)
     event BondRedeemed(string indexed isin, address indexed holder, uint256 value, uint256 wnokAmount);