_setListing(proposedListing, msg.sender, _collateral, _pricePerToken, block.timestamp);

// Sets collateral amount to pending balances for withdrawal
pendingBalances[_vault][proposedListing.proposer] += proposedListing.collateral;
--- a/test/seaport/OptimisticListingSeaport.t.sol
+++ b/test/seaport/OptimisticListingSeaport.t.sol
@@ -379,8 +379,11 @@ contract OptimisticListingSeaportTest is SeaportTestUtil {
     /// ===== LIST =====
     /// ================
     function testList(uint256 _collateral, uint256 _price) public {
         // setup
         testPropose(_collateral, _price);
+        assertEq(optimistic.pendingBalances(vault, bob), 0);
         _increaseTime(PROPOSAL_PERIOD);
         _collateral = _boundCollateral(_collateral, bobTokenBalance);
         _price = _boundPrice(_price);
