feat(billboard): skip if auction is already cleared

.gas-snapshot

@@ -12,15 +12,15 @@ ACLManagerTest:testTransferRole() (gas: 21528)
 BillboardTest:testAddToWhitelist() (gas: 37205)
 BillboardTest:testApproveAndTransfer() (gas: 162735)
 BillboardTest:testCalculateTax() (gas: 29439)
-BillboardTest:testCannnotWithdrawTaxIfSmallAmount(uint8) (runs: 256, μ: 419677, ~: 433681)
-BillboardTest:testCannnotWithdrawTaxIfZero() (gas: 385862)
+BillboardTest:testCannnotWithdrawTaxIfSmallAmount(uint8) (runs: 256, μ: 419891, ~: 433722)
+BillboardTest:testCannnotWithdrawTaxIfZero() (gas: 385903)
 BillboardTest:testCannotAddToWhitelistByAttacker() (gas: 11137)
 BillboardTest:testCannotApproveByAttacker() (gas: 130388)
-BillboardTest:testCannotClearAuctionIfAuctionNotEnded() (gas: 604134)
+BillboardTest:testCannotClearAuctionIfAuctionNotEnded() (gas: 585072)
 BillboardTest:testCannotClearAuctionOnNewBoard() (gas: 136029)
 BillboardTest:testCannotMintBoardByAttacker() (gas: 13332)
 BillboardTest:testCannotPlaceBidByAttacker() (gas: 141747)
-BillboardTest:testCannotPlaceBidTwice(uint96) (runs: 256, μ: 650687, ~: 656918)
+BillboardTest:testCannotPlaceBidTwice(uint96) (runs: 256, μ: 631625, ~: 637856)
 BillboardTest:testCannotRemoveToWhitelistByAttacker() (gas: 11204)
 BillboardTest:testCannotSafeTransferByAttacker() (gas: 127555)
 BillboardTest:testCannotSetBoardProprtiesByAttacker() (gas: 156298)
@@ -29,35 +29,35 @@ BillboardTest:testCannotSetTaxRateByAttacker() (gas: 11106)
 BillboardTest:testCannotTransferByOperator() (gas: 132888)
 BillboardTest:testCannotTransferToZeroAddress() (gas: 128375)
 BillboardTest:testCannotUpgradeRegistryByAttacker() (gas: 11228)
-BillboardTest:testCannotWithBidTwice(uint96) (runs: 256, μ: 934036, ~: 934036)
-BillboardTest:testCannotWithdrawBidIfAuctionNotCleared(uint96) (runs: 256, μ: 770628, ~: 770628)
-BillboardTest:testCannotWithdrawBidIfAuctionNotEnded(uint96) (runs: 256, μ: 645425, ~: 645425)
-BillboardTest:testCannotWithdrawBidIfNotFound() (gas: 419086)
-BillboardTest:testCannotWithdrawBidIfWon(uint96) (runs: 256, μ: 740484, ~: 740484)
+BillboardTest:testCannotWithBidTwice(uint96) (runs: 256, μ: 915015, ~: 915015)
+BillboardTest:testCannotWithdrawBidIfAuctionNotCleared(uint96) (runs: 256, μ: 751566, ~: 751566)
+BillboardTest:testCannotWithdrawBidIfAuctionNotEnded(uint96) (runs: 256, μ: 626363, ~: 626363)
+BillboardTest:testCannotWithdrawBidIfNotFound() (gas: 419127)
+BillboardTest:testCannotWithdrawBidIfWon(uint96) (runs: 256, μ: 721463, ~: 721463)
 BillboardTest:testCannotWithdrawTaxByAttacker() (gas: 21053)
-BillboardTest:testClearAuctionIfAuctionEnded() (gas: 649619)
-BillboardTest:testClearAuctionsIfAuctionEnded() (gas: 1206340)
-BillboardTest:testGetBids(uint8,uint8,uint8) (runs: 256, μ: 2871675, ~: 1453869)
+BillboardTest:testClearAuctionIfAuctionEnded() (gas: 630598)
+BillboardTest:testClearAuctionsIfAuctionEnded() (gas: 1168298)
+BillboardTest:testGetBids(uint8,uint8,uint8) (runs: 256, μ: 2724918, ~: 1356638)
 BillboardTest:testGetTokenURI() (gas: 155303)
 BillboardTest:testMintBoard() (gas: 225987)
 BillboardTest:testMintBoardByWhitelist() (gas: 157167)
 BillboardTest:testMintBoardIfOpened() (gas: 130861)
-BillboardTest:testPlaceBidByWhitelist() (gas: 470026)
-BillboardTest:testPlaceBidIfAuctionEnded() (gas: 937087)
-BillboardTest:testPlaceBidOnNewBoard(uint96) (runs: 256, μ: 519419, ~: 529745)
-BillboardTest:testPlaceBidWithHigherPrice(uint96) (runs: 256, μ: 766815, ~: 774045)
-BillboardTest:testPlaceBidWithSamePrices(uint96) (runs: 256, μ: 764942, ~: 776618)
-BillboardTest:testPlaceBidZeroPrice() (gas: 357801)
+BillboardTest:testPlaceBidByWhitelist() (gas: 470067)
+BillboardTest:testPlaceBidIfAuctionEnded() (gas: 918066)
+BillboardTest:testPlaceBidOnNewBoard(uint96) (runs: 256, μ: 519460, ~: 529786)
+BillboardTest:testPlaceBidWithHigherPrice(uint96) (runs: 256, μ: 747753, ~: 754983)
+BillboardTest:testPlaceBidWithSamePrices(uint96) (runs: 256, μ: 745880, ~: 757556)
+BillboardTest:testPlaceBidZeroPrice() (gas: 357842)
 BillboardTest:testRemoveToWhitelist() (gas: 24957)
 BillboardTest:testSafeTransferByOperator() (gas: 141354)
 BillboardTest:testSetBoardProperties() (gas: 305524)
 BillboardTest:testSetBoardPropertiesAfterTransfer() (gas: 334252)
 BillboardTest:testSetIsOpened() (gas: 15978)
 BillboardTest:testSetTaxRate() (gas: 27263)
-BillboardTest:testSomethin() (gas: 1698254)
-BillboardTest:testUpgradeRegistry() (gas: 2725063)
-BillboardTest:testWithdrawBid(uint96) (runs: 256, μ: 935332, ~: 935332)
-BillboardTest:testWithdrawTax(uint96) (runs: 256, μ: 509539, ~: 509539)
+BillboardTest:testSomethin() (gas: 1641191)
+BillboardTest:testUpgradeRegistry() (gas: 2729870)
+BillboardTest:testWithdrawBid(uint96) (runs: 256, μ: 916311, ~: 916311)
+BillboardTest:testWithdrawTax(uint96) (runs: 256, μ: 509580, ~: 509580)
 CurationTest:testCannotCurateERC20CurateZeroAmount() (gas: 12194)
 CurationTest:testCannotCurateERC20EmptyURI() (gas: 15797)
 CurationTest:testCannotCurateERC20IfNotApproval() (gas: 21624)

src/Billboard/Billboard.sol

@@ -167,13 +167,20 @@ contract Billboard is IBillboard {
 
     function _clearAuction(uint256 tokenId_, address boardCreator_, uint256 nextAuctionId_) private {
         IBillboardRegistry.Auction memory _nextAuction = registry.getAuction(tokenId_, nextAuctionId_);
+
+        // skip if auction is already cleared
+        if (_nextAuction.leaseEndAt != 0) {
+            return;
+        }
+
+        address _prevOwner = registry.ownerOf(tokenId_);
+
         IBillboardRegistry.Bid memory _highestBid = registry.getBid(
             tokenId_,
             nextAuctionId_,
             _nextAuction.highestBidder
         );
 
-        address _prevOwner = registry.ownerOf(tokenId_);
         if (_highestBid.price > 0) {
             // transfer bid price to board owner (previous tenant or creator)
             registry.transferAmount(_prevOwner, _highestBid.price);