From 93f7f17cc04e22d88d92afec8f241a70494e0fce Mon Sep 17 00:00:00 2001
From: Prathamesh Musale <prathamesh.musale0@gmail.com>
Date: Fri, 20 Sep 2024 11:54:36 +0530
Subject: [PATCH] Use stable sort for sorting bids

---
 x/auction/keeper/keeper.go | 42 +++++++++++++++-----------------------
 1 file changed, 16 insertions(+), 26 deletions(-)

diff --git a/x/auction/keeper/keeper.go b/x/auction/keeper/keeper.go
index 9a8ec3e5..2cb4cde4 100644
--- a/x/auction/keeper/keeper.go
+++ b/x/auction/keeper/keeper.go
@@ -825,7 +825,7 @@ func (k Keeper) pickProviderAuctionWinners(ctx sdk.Context, auction *auctiontype
 	}
 
 	// Sort the valid bids
-	slices.SortFunc(revealedBids, func(a, b *auctiontypes.Bid) int {
+	slices.SortStableFunc(revealedBids, func(a, b *auctiontypes.Bid) int {
 		if a.BidAmount.Amount.LT(b.BidAmount.Amount) {
 			return -1
 		} else if a.BidAmount.Amount.GT(b.BidAmount.Amount) {
@@ -887,7 +887,6 @@ func (k Keeper) pickProviderAuctionWinners(ctx sdk.Context, auction *auctiontype
 	}
 
 	// Process winner accounts (if nobody bids, there won't be a winner).
-	totalLockedAmount := auction.MaxPrice.Amount.Mul(math.NewInt(int64(auction.NumProviders)))
 	if len(winnerBids) > 0 {
 		for _, bid := range winnerBids {
 			winnerAddress, err := sdk.AccAddressFromBech32(bid.BidderAddress)
@@ -903,32 +902,23 @@ func (k Keeper) pickProviderAuctionWinners(ctx sdk.Context, auction *auctiontype
 				panic(sdkErr)
 			}
 		}
+	}
 
-		// Send back extra amount to auction creator
-		totalAmountPaid := auction.WinningPrice.Amount.Mul(math.NewInt(int64(len(winnerBids))))
-		extraAmount := sdk.NewCoin(auction.MaxPrice.Denom, totalLockedAmount.Sub(totalAmountPaid))
+	// Send back any leftover locked amount to auction creator
+	// All of it in case of no winners
+	totalLockedAmount := auction.MaxPrice.Amount.Mul(math.NewInt(int64(auction.NumProviders)))
+	totalAmountPaid := auction.WinningPrice.Amount.Mul(math.NewInt(int64(len(auction.WinnerAddresses))))
+	creatorLeftOverAmount := sdk.NewCoin(auction.MaxPrice.Denom, totalLockedAmount.Sub(totalAmountPaid))
 
-		sdkErr := k.bankKeeper.SendCoinsFromModuleToAccount(
-			ctx,
-			auctiontypes.ModuleName,
-			sdk.AccAddress(auction.OwnerAddress),
-			sdk.NewCoins(extraAmount),
-		)
-		if sdkErr != nil {
-			k.Logger(ctx).Error(fmt.Sprintf("Auction error returning extra locked amount: %v", sdkErr))
-			panic(sdkErr)
-		}
-	} else {
-		// Return all locked amount in case of no winners
-		sdkErr := k.bankKeeper.SendCoinsFromModuleToAccount(
-			ctx,
-			auctiontypes.ModuleName,
-			sdk.AccAddress(auction.OwnerAddress),
-			sdk.NewCoins(sdk.NewCoin(auction.MaxPrice.Denom, totalLockedAmount)))
-		if sdkErr != nil {
-			k.Logger(ctx).Error(fmt.Sprintf("Auction error returning bid amount: %v", sdkErr))
-			panic(sdkErr)
-		}
+	sdkErr := k.bankKeeper.SendCoinsFromModuleToAccount(
+		ctx,
+		auctiontypes.ModuleName,
+		sdk.AccAddress(auction.OwnerAddress),
+		sdk.NewCoins(creatorLeftOverAmount),
+	)
+	if sdkErr != nil {
+		k.Logger(ctx).Error(fmt.Sprintf("Auction error returning leftover locked amount: %v", sdkErr))
+		panic(sdkErr)
 	}
 
 	// Notify other modules (hook).