fix: fix bug in PositionAssets when position liquidity is zero

x/amm/keeper/position.go

@@ -190,6 +190,11 @@ func (k Keeper) PositionAssets(ctx sdk.Context, positionId uint64) (coin0, coin1
 		return coin0, coin1, sdkerrors.Wrap(sdkerrors.ErrNotFound, "position not found")
 	}
 	pool := k.MustGetPool(ctx, position.PoolId)
+	if position.Liquidity.IsZero() {
+		coin0 = sdk.NewInt64Coin(pool.Denom0, 0)
+		coin1 = sdk.NewInt64Coin(pool.Denom1, 0)
+		return
+	}
 	ctx, _ = ctx.CacheContext()
 	_, amt0, amt1 := k.modifyPosition(
 		ctx, pool, position.MustGetOwnerAddress(), position.LowerTick, position.UpperTick, position.Liquidity.Neg())

x/amm/keeper/position_test.go

@@ -97,7 +97,7 @@ func (s *KeeperTestSuite) TestRewardsPool() {
 		lpAddr, pool2.Id, utils.ParseDec("9"), utils.ParseDec("12"), utils.ParseCoins("100_000000uatom,1000_000000uusd"))
 
 	ordererAddr := s.FundedAccount(2, enoughCoins)
-	s.PlaceLimitOrder(market1.Id, ordererAddr, true, utils.ParseDec("6"), sdk.NewDec(1_000000),0 )
+	s.PlaceLimitOrder(market1.Id, ordererAddr, true, utils.ParseDec("6"), sdk.NewDec(1_000000), 0)
 	s.PlaceLimitOrder(market2.Id, ordererAddr, false, utils.ParseDec("9"), sdk.NewDec(1_000000), 0)
 
 	s.AssertEqual(utils.ParseCoins("1499ucre,2620uusd"), s.GetAllBalances(pool1.MustGetRewardsPoolAddress()))
@@ -139,3 +139,26 @@ func (s *KeeperTestSuite) TestLastRemoveLiquidity() {
 	// No balances left in the pool.
 	s.AssertEqual(sdk.Coins{}, s.GetAllBalances(pool.MustGetReserveAddress()))
 }
+
+func (s *KeeperTestSuite) TestPositionAssets_ZeroLiquidity() {
+	_, pool := s.CreateMarketAndPool("ucre", "uusd", utils.ParseDec("5"))
+
+	lpAddr1 := s.FundedAccount(1, enoughCoins)
+
+	position, _, _ := s.AddLiquidity(
+		lpAddr1, pool.Id, utils.ParseDec("4"), utils.ParseDec("6"),
+		utils.ParseCoins("100_000000ucre,500_000000uusd"))
+
+	coin0, coin1, err := s.keeper.PositionAssets(s.Ctx, position.Id)
+	s.Require().NoError(err)
+	s.AssertEqual(utils.ParseCoin("82529840ucre"), coin0)
+	s.AssertEqual(utils.ParseCoin("499999999uusd"), coin1)
+
+	// Remove all liquidity from the position.
+	s.RemoveLiquidity(lpAddr1, position.Id, position.Liquidity)
+
+	coin0, coin1, err = s.keeper.PositionAssets(s.Ctx, position.Id)
+	s.Require().NoError(err)
+	s.AssertEqual(utils.ParseCoin("0ucre"), coin0)
+	s.AssertEqual(utils.ParseCoin("0uusd"), coin1)
+}

x/liquidstaking/keeper/keeper_test.go

@@ -366,6 +366,15 @@ func (s *KeeperTestSuite) addLiquidity(
 	return
 }
 
+func (s *KeeperTestSuite) removeLiquidity(
+	ownerAddr sdk.AccAddress, positionId uint64, liquidity sdk.Int) (position ammtypes.Position, amt sdk.Coins) {
+	s.T().Helper()
+	var err error
+	position, amt, err = s.app.AMMKeeper.RemoveLiquidity(s.ctx, ownerAddr, ownerAddr, positionId, liquidity)
+	s.Require().NoError(err)
+	return
+}
+
 func (s *KeeperTestSuite) createPublicPosition(
 	poolId uint64, lowerPrice, upperPrice sdk.Dec, minBidAmt sdk.Int, feeRate sdk.Dec) liquidammtypes.PublicPosition {
 	s.T().Helper()

x/liquidstaking/keeper/tally_test.go

@@ -569,7 +569,7 @@ func (s *KeeperTestSuite) TestCalcLiquidStakingVotingPower() {
 	s.Require().Equal(sdk.NewInt(200_000000), s.keeper.CalcLiquidStakingVotingPower(s.ctx, delB))
 
 	_, pool := s.createMarketAndPool(params.LiquidBondDenom, sdk.DefaultBondDenom, utils.ParseDec("1"))
-	s.addLiquidity(
+	position1, _, _ := s.addLiquidity(
 		delA, pool.Id, utils.ParseDec("1"), utils.ParseDec("1.2"),
 		sdk.NewCoins(
 			sdk.NewInt64Coin(params.LiquidBondDenom, 10_000000),
@@ -609,4 +609,10 @@ func (s *KeeperTestSuite) TestCalcLiquidStakingVotingPower() {
 	// There might be a small amount of error again.
 	s.Require().Equal(sdk.NewInt(99_999998), s.keeper.CalcLiquidStakingVotingPower(s.ctx, delA))
 	s.Require().Equal(sdk.NewInt(199_999998), s.keeper.CalcLiquidStakingVotingPower(s.ctx, delB))
+
+	// Remove all liquidity
+	s.removeLiquidity(delA, position1.Id, position1.Liquidity)
+
+	s.Require().Equal(sdk.NewInt(99_999998), s.keeper.CalcLiquidStakingVotingPower(s.ctx, delA))
+	s.Require().Equal(sdk.NewInt(199_999998), s.keeper.CalcLiquidStakingVotingPower(s.ctx, delB))
 }