0g-chain/x/hard/keeper/interest_test.go
Denali Marsh f7a73c9245
Hard: suppliers earn interest (#749)
* update to borrow interest factor

* add supply interest factor to accrue interest

* supply interest factor keeper methods

* fix potential bug with user borrow indexing

* sync supply interest on deposit/withdraw

* separate withdraw/deposit

* relocate interest sync methods

* update comment

* simplify supply interest statement

* check truncated int not zero

* add .sub(storedAmount) back

* add store key suppliedcoins

* increment/decrement supplied coins

* update withdraw with new accounting

* update withdraw test

* catch repay edge case

* unit tests

* TestSupplyInterest scaffolding

* test notes

* temp: interest test

* example test

* changes, test checks more state

* fix: calculate supply interest directly

* fix: catch divide by zero

* add state checks back into interest test

* add snapshot test cases

* test owed supplied interest paid at correct ratio

* test user supply syncs user's borrow interest

* remove print statements and clean up

* refactor indented logic

* test supply/borrow multiple coins

* update decoder test

Co-authored-by: karzak <kjydavis3@gmail.com>
2021-01-07 11:23:05 +01:00

1344 lines
48 KiB
Go

package keeper_test
import (
"testing"
"time"
sdk "github.com/cosmos/cosmos-sdk/types"
"github.com/stretchr/testify/suite"
abci "github.com/tendermint/tendermint/abci/types"
"github.com/tendermint/tendermint/crypto"
tmtime "github.com/tendermint/tendermint/types/time"
"github.com/kava-labs/kava/app"
"github.com/kava-labs/kava/x/hard"
"github.com/kava-labs/kava/x/hard/types"
"github.com/kava-labs/kava/x/pricefeed"
)
type InterestTestSuite struct {
suite.Suite
}
func (suite *InterestTestSuite) TestCalculateUtilizationRatio() {
type args struct {
cash sdk.Dec
borrows sdk.Dec
reserves sdk.Dec
expectedValue sdk.Dec
}
type test struct {
name string
args args
}
testCases := []test{
{
"normal",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("100"),
expectedValue: sdk.MustNewDecFromStr("0.847457627118644068"),
},
},
{
"high util ratio",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("250000"),
reserves: sdk.MustNewDecFromStr("100"),
expectedValue: sdk.MustNewDecFromStr("0.996412913511359107"),
},
},
{
"very high util ratio",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("250000000000"),
reserves: sdk.MustNewDecFromStr("100"),
expectedValue: sdk.MustNewDecFromStr("0.999999996400000013"),
},
},
{
"low util ratio",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("50"),
reserves: sdk.MustNewDecFromStr("100"),
expectedValue: sdk.MustNewDecFromStr("0.052631578947368421"),
},
},
{
"very low util ratio",
args{
cash: sdk.MustNewDecFromStr("10000000"),
borrows: sdk.MustNewDecFromStr("50"),
reserves: sdk.MustNewDecFromStr("100"),
expectedValue: sdk.MustNewDecFromStr("0.000005000025000125"),
},
},
}
for _, tc := range testCases {
suite.Run(tc.name, func() {
utilRatio := hard.CalculateUtilizationRatio(tc.args.cash, tc.args.borrows, tc.args.reserves)
suite.Require().Equal(tc.args.expectedValue, utilRatio)
})
}
}
func (suite *InterestTestSuite) TestCalculateBorrowRate() {
type args struct {
cash sdk.Dec
borrows sdk.Dec
reserves sdk.Dec
model types.InterestRateModel
expectedValue sdk.Dec
}
type test struct {
name string
args args
}
// Normal model has:
// - BaseRateAPY: 0.0
// - BaseMultiplier: 0.1
// - Kink: 0.8
// - JumpMultiplier: 0.5
normalModel := types.NewInterestRateModel(sdk.MustNewDecFromStr("0"), sdk.MustNewDecFromStr("0.1"), sdk.MustNewDecFromStr("0.8"), sdk.MustNewDecFromStr("0.5"))
testCases := []test{
{
"normal no jump",
args{
cash: sdk.MustNewDecFromStr("5000"),
borrows: sdk.MustNewDecFromStr("1000"),
reserves: sdk.MustNewDecFromStr("1000"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.020000000000000000"),
},
},
{
"normal with jump",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("100"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.103728813559322034"),
},
},
{
"high cash",
args{
cash: sdk.MustNewDecFromStr("10000000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("100"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.000049975511999120"),
},
},
{
"high borrows",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000000000000"),
reserves: sdk.MustNewDecFromStr("100"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.179999999910000000"),
},
},
{
"high reserves",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("1000000000000"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.180000000000000000"),
},
},
{
"random numbers",
args{
cash: sdk.MustNewDecFromStr("125"),
borrows: sdk.MustNewDecFromStr("11"),
reserves: sdk.MustNewDecFromStr("82"),
model: normalModel,
expectedValue: sdk.MustNewDecFromStr("0.020370370370370370"),
},
},
{
"increased base multiplier",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("100"),
model: types.NewInterestRateModel(sdk.MustNewDecFromStr("0"), sdk.MustNewDecFromStr("0.5"), sdk.MustNewDecFromStr("0.8"), sdk.MustNewDecFromStr("1.0")),
expectedValue: sdk.MustNewDecFromStr("0.447457627118644068"),
},
},
{
"decreased kink",
args{
cash: sdk.MustNewDecFromStr("1000"),
borrows: sdk.MustNewDecFromStr("5000"),
reserves: sdk.MustNewDecFromStr("100"),
model: types.NewInterestRateModel(sdk.MustNewDecFromStr("0"), sdk.MustNewDecFromStr("0.5"), sdk.MustNewDecFromStr("0.1"), sdk.MustNewDecFromStr("1.0")),
expectedValue: sdk.MustNewDecFromStr("0.797457627118644068"),
},
},
}
for _, tc := range testCases {
suite.Run(tc.name, func() {
borrowRate, err := hard.CalculateBorrowRate(tc.args.model, tc.args.cash, tc.args.borrows, tc.args.reserves)
suite.Require().NoError(err)
suite.Require().Equal(tc.args.expectedValue, borrowRate)
})
}
}
func (suite *InterestTestSuite) TestCalculateBorrowInterestFactor() {
type args struct {
perSecondInterestRate sdk.Dec
timeElapsed sdk.Int
expectedValue sdk.Dec
}
type test struct {
name string
args args
}
oneYearInSeconds := int64(31536000)
testCases := []test{
{
"1 year",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000005555"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("1.191463614477847370"),
},
},
{
"10 year",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000005555"),
timeElapsed: sdk.NewInt(oneYearInSeconds * 10),
expectedValue: sdk.MustNewDecFromStr("5.765113233897391189"),
},
},
{
"1 month",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000005555"),
timeElapsed: sdk.NewInt(oneYearInSeconds / 12),
expectedValue: sdk.MustNewDecFromStr("1.014705619075717373"),
},
},
{
"1 day",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000005555"),
timeElapsed: sdk.NewInt(oneYearInSeconds / 365),
expectedValue: sdk.MustNewDecFromStr("1.000480067194057924"),
},
},
{
"1 year: low interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000000555"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("1.017656545925063632"),
},
},
{
"1 year, lower interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000000055"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("1.001735985079841390"),
},
},
{
"1 year, lowest interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000000005"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("1.000157692432076670"),
},
},
{
"1 year: high interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000055555"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("5.766022095987868825"),
},
},
{
"1 year: higher interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000000555555"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("40628388.864535408465693310"),
},
},
// If we raise the per second interest rate too much we'll cause an integer overflow.
// For example, perSecondInterestRate: '1.000005555555' will cause a panic.
{
"1 year: highest interest rate",
args{
perSecondInterestRate: sdk.MustNewDecFromStr("1.000001555555"),
timeElapsed: sdk.NewInt(oneYearInSeconds),
expectedValue: sdk.MustNewDecFromStr("2017093013158200407564.613502861572552603"),
},
},
}
for _, tc := range testCases {
interestFactor := hard.CalculateBorrowInterestFactor(tc.args.perSecondInterestRate, tc.args.timeElapsed)
suite.Require().Equal(tc.args.expectedValue, interestFactor)
}
}
func (suite *InterestTestSuite) TestCalculateSupplyInterestFactor() {
type args struct {
newInterest sdk.Dec
cash sdk.Dec
borrows sdk.Dec
reserves sdk.Dec
reserveFactor sdk.Dec
expectedValue sdk.Dec
}
type test struct {
name string
args args
}
testCases := []test{
{
"low new interest",
args{
newInterest: sdk.MustNewDecFromStr("1"),
cash: sdk.MustNewDecFromStr("100.0"),
borrows: sdk.MustNewDecFromStr("1000.0"),
reserves: sdk.MustNewDecFromStr("10.0"),
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedValue: sdk.MustNewDecFromStr("1.000917431192660550"),
},
},
{
"medium new interest",
args{
newInterest: sdk.MustNewDecFromStr("5"),
cash: sdk.MustNewDecFromStr("100.0"),
borrows: sdk.MustNewDecFromStr("1000.0"),
reserves: sdk.MustNewDecFromStr("10.0"),
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedValue: sdk.MustNewDecFromStr("1.004587155963302752"),
},
},
{
"high new interest",
args{
newInterest: sdk.MustNewDecFromStr("10"),
cash: sdk.MustNewDecFromStr("100.0"),
borrows: sdk.MustNewDecFromStr("1000.0"),
reserves: sdk.MustNewDecFromStr("10.0"),
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedValue: sdk.MustNewDecFromStr("1.009174311926605505"),
},
},
}
for _, tc := range testCases {
interestFactor := hard.CalculateSupplyInterestFactor(tc.args.newInterest,
tc.args.cash, tc.args.borrows, tc.args.reserves)
suite.Require().Equal(tc.args.expectedValue, interestFactor)
}
}
func (suite *InterestTestSuite) TestAPYToSPY() {
type args struct {
apy sdk.Dec
expectedValue sdk.Dec
}
type test struct {
name string
args args
expectError bool
}
testCases := []test{
{
"lowest apy",
args{
apy: sdk.MustNewDecFromStr("0.005"),
expectedValue: sdk.MustNewDecFromStr("0.999999831991472557"),
},
false,
},
{
"lower apy",
args{
apy: sdk.MustNewDecFromStr("0.05"),
expectedValue: sdk.MustNewDecFromStr("0.999999905005957279"),
},
false,
},
{
"medium-low apy",
args{
apy: sdk.MustNewDecFromStr("0.5"),
expectedValue: sdk.MustNewDecFromStr("0.999999978020447332"),
},
false,
},
{
"medium-high apy",
args{
apy: sdk.MustNewDecFromStr("5"),
expectedValue: sdk.MustNewDecFromStr("1.000000051034942717"),
},
false,
},
{
"high apy",
args{
apy: sdk.MustNewDecFromStr("50"),
expectedValue: sdk.MustNewDecFromStr("1.000000124049443433"),
},
false,
},
{
"highest apy",
args{
apy: sdk.MustNewDecFromStr("177"),
expectedValue: sdk.MustNewDecFromStr("1.000002441641340532"),
},
false,
},
{
"out of bounds error after 178",
args{
apy: sdk.MustNewDecFromStr("178"),
expectedValue: sdk.ZeroDec(),
},
true,
},
}
for _, tc := range testCases {
suite.Run(tc.name, func() {
spy, err := hard.APYToSPY(tc.args.apy)
if tc.expectError {
suite.Require().Error(err)
} else {
suite.Require().NoError(err)
suite.Require().Equal(tc.args.expectedValue, spy)
}
})
}
}
type ExpectedBorrowInterest struct {
elapsedTime int64
shouldBorrow bool
borrowCoin sdk.Coin
}
func (suite *KeeperTestSuite) TestBorrowInterest() {
type args struct {
user sdk.AccAddress
initialBorrowerCoins sdk.Coins
initialModuleCoins sdk.Coins
borrowCoinDenom string
borrowCoins sdk.Coins
interestRateModel types.InterestRateModel
reserveFactor sdk.Dec
expectedInterestSnaphots []ExpectedBorrowInterest
}
type errArgs struct {
expectPass bool
contains string
}
type interestTest struct {
name string
args args
errArgs errArgs
}
normalModel := types.NewInterestRateModel(sdk.MustNewDecFromStr("0"), sdk.MustNewDecFromStr("0.1"), sdk.MustNewDecFromStr("0.8"), sdk.MustNewDecFromStr("0.5"))
oneDayInSeconds := int64(86400)
oneWeekInSeconds := int64(604800)
oneMonthInSeconds := int64(2592000)
oneYearInSeconds := int64(31536000)
testCases := []interestTest{
{
"one day",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneDayInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one week",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneWeekInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one month",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneMonthInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one year",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneYearInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"0 reserve factor",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneYearInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"borrow during snapshot",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneYearInSeconds,
shouldBorrow: true,
borrowCoin: sdk.NewCoin("ukava", sdk.NewInt(1*KAVA_CF)),
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"multiple snapshots",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneMonthInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
{
elapsedTime: oneMonthInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"varied snapshots",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
borrowCoinDenom: "ukava",
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedBorrowInterest{
{
elapsedTime: oneDayInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
{
elapsedTime: oneWeekInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
{
elapsedTime: oneMonthInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
{
elapsedTime: oneYearInSeconds,
shouldBorrow: false,
borrowCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
}
for _, tc := range testCases {
suite.Run(tc.name, func() {
// Initialize test app and set context
tApp := app.NewTestApp()
ctx := tApp.NewContext(true, abci.Header{Height: 1, Time: tmtime.Now()})
// Auth module genesis state
authGS := app.NewAuthGenState(
[]sdk.AccAddress{tc.args.user},
[]sdk.Coins{tc.args.initialBorrowerCoins},
)
// Hard module genesis state
hardGS := types.NewGenesisState(types.NewParams(
true,
types.DistributionSchedules{
types.NewDistributionSchedule(true, "ukava", time.Date(2020, 10, 8, 14, 0, 0, 0, time.UTC), time.Date(2020, 11, 22, 14, 0, 0, 0, time.UTC), sdk.NewCoin("hard", sdk.NewInt(5000)), time.Date(2021, 11, 22, 14, 0, 0, 0, time.UTC), types.Multipliers{types.NewMultiplier(types.Small, 0, sdk.MustNewDecFromStr("0.33")), types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.5")), types.NewMultiplier(types.Medium, 24, sdk.OneDec())}),
},
types.DelegatorDistributionSchedules{types.NewDelegatorDistributionSchedule(
types.NewDistributionSchedule(true, "usdx", time.Date(2020, 10, 8, 14, 0, 0, 0, time.UTC), time.Date(2025, 10, 8, 14, 0, 0, 0, time.UTC), sdk.NewCoin("hard", sdk.NewInt(500)), time.Date(2026, 10, 8, 14, 0, 0, 0, time.UTC), types.Multipliers{types.NewMultiplier(types.Small, 0, sdk.MustNewDecFromStr("0.33")), types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.5")), types.NewMultiplier(types.Medium, 24, sdk.OneDec())}),
time.Hour*24,
),
},
types.MoneyMarkets{
types.NewMoneyMarket("ukava",
types.NewBorrowLimit(false, sdk.NewDec(100000000*KAVA_CF), sdk.MustNewDecFromStr("0.8")), // Borrow Limit
"kava:usd", // Market ID
sdk.NewInt(KAVA_CF), // Conversion Factor
sdk.NewInt(USDX_CF*1000), // Auction Size
tc.args.interestRateModel, // Interest Rate Model
tc.args.reserveFactor, // Reserve Factor
sdk.ZeroDec()), // Keeper Reward Percentage
},
0, // LTV counter
), types.DefaultPreviousBlockTime, types.DefaultDistributionTimes)
// Pricefeed module genesis state
pricefeedGS := pricefeed.GenesisState{
Params: pricefeed.Params{
Markets: []pricefeed.Market{
{MarketID: "kava:usd", BaseAsset: "kava", QuoteAsset: "usd", Oracles: []sdk.AccAddress{}, Active: true},
},
},
PostedPrices: []pricefeed.PostedPrice{
{
MarketID: "kava:usd",
OracleAddress: sdk.AccAddress{},
Price: sdk.MustNewDecFromStr("2.00"),
Expiry: time.Now().Add(100 * time.Hour),
},
},
}
// Initialize test application
tApp.InitializeFromGenesisStates(authGS,
app.GenesisState{pricefeed.ModuleName: pricefeed.ModuleCdc.MustMarshalJSON(pricefeedGS)},
app.GenesisState{types.ModuleName: types.ModuleCdc.MustMarshalJSON(hardGS)})
// Mint coins to Hard module account
supplyKeeper := tApp.GetSupplyKeeper()
supplyKeeper.MintCoins(ctx, types.ModuleAccountName, tc.args.initialModuleCoins)
keeper := tApp.GetHardKeeper()
suite.app = tApp
suite.ctx = ctx
suite.keeper = keeper
var err error
// Run begin blocker and store initial block time
hard.BeginBlocker(suite.ctx, suite.keeper)
// Deposit 2x as many coins for each coin we intend to borrow
depositCoins := sdk.NewCoins()
for _, borrowCoin := range tc.args.borrowCoins {
depositCoins = depositCoins.Add(sdk.NewCoin(borrowCoin.Denom, borrowCoin.Amount.Mul(sdk.NewInt(2))))
}
err = suite.keeper.Deposit(suite.ctx, tc.args.user, depositCoins)
suite.Require().NoError(err)
// Borrow coins
err = suite.keeper.Borrow(suite.ctx, tc.args.user, tc.args.borrowCoins)
suite.Require().NoError(err)
// Check that the initial module-level borrow balance is correct and store it
initialBorrowedCoins, _ := suite.keeper.GetBorrowedCoins(suite.ctx)
suite.Require().Equal(tc.args.borrowCoins, initialBorrowedCoins)
// Check interest levels for each snapshot
prevCtx := suite.ctx
for _, snapshot := range tc.args.expectedInterestSnaphots {
// ---------------------------- Calculate expected interest ----------------------------
// 1. Get cash, borrows, reserves, and borrow index
cashPrior := suite.getModuleAccountAtCtx(types.ModuleName, prevCtx).GetCoins().AmountOf(tc.args.borrowCoinDenom)
borrowCoinsPrior, borrowCoinsPriorFound := suite.keeper.GetBorrowedCoins(prevCtx)
suite.Require().True(borrowCoinsPriorFound)
borrowCoinPriorAmount := borrowCoinsPrior.AmountOf(tc.args.borrowCoinDenom)
reservesPrior, foundReservesPrior := suite.keeper.GetTotalReserves(prevCtx, tc.args.borrowCoinDenom)
if !foundReservesPrior {
reservesPrior = sdk.NewCoin(tc.args.borrowCoinDenom, sdk.ZeroInt())
}
interestFactorPrior, foundInterestFactorPrior := suite.keeper.GetBorrowInterestFactor(prevCtx, tc.args.borrowCoinDenom)
suite.Require().True(foundInterestFactorPrior)
// 2. Calculate expected interest owed
borrowRateApy, err := hard.CalculateBorrowRate(tc.args.interestRateModel, sdk.NewDecFromInt(cashPrior), sdk.NewDecFromInt(borrowCoinPriorAmount), sdk.NewDecFromInt(reservesPrior.Amount))
suite.Require().NoError(err)
// Convert from APY to SPY, expressed as (1 + borrow rate)
borrowRateSpy, err := hard.APYToSPY(sdk.OneDec().Add(borrowRateApy))
suite.Require().NoError(err)
interestFactor := hard.CalculateBorrowInterestFactor(borrowRateSpy, sdk.NewInt(snapshot.elapsedTime))
expectedInterest := (interestFactor.Mul(sdk.NewDecFromInt(borrowCoinPriorAmount)).TruncateInt()).Sub(borrowCoinPriorAmount)
expectedReserves := reservesPrior.Add(sdk.NewCoin(tc.args.borrowCoinDenom, sdk.NewDecFromInt(expectedInterest).Mul(tc.args.reserveFactor).TruncateInt()))
expectedInterestFactor := interestFactorPrior.Mul(interestFactor)
// -------------------------------------------------------------------------------------
// Set up snapshot chain context and run begin blocker
runAtTime := time.Unix(prevCtx.BlockTime().Unix()+(snapshot.elapsedTime), 0)
snapshotCtx := prevCtx.WithBlockTime(runAtTime)
hard.BeginBlocker(snapshotCtx, suite.keeper)
// Check that the total amount of borrowed coins has increased by expected interest amount
expectedBorrowedCoins := borrowCoinsPrior.AmountOf(tc.args.borrowCoinDenom).Add(expectedInterest)
currBorrowedCoins, _ := suite.keeper.GetBorrowedCoins(snapshotCtx)
suite.Require().Equal(expectedBorrowedCoins, currBorrowedCoins.AmountOf(tc.args.borrowCoinDenom))
// Check that the total reserves have changed as expected
currTotalReserves, _ := suite.keeper.GetTotalReserves(snapshotCtx, tc.args.borrowCoinDenom)
suite.Require().Equal(expectedReserves, currTotalReserves)
// Check that the borrow index has increased as expected
currIndexPrior, _ := suite.keeper.GetBorrowInterestFactor(snapshotCtx, tc.args.borrowCoinDenom)
suite.Require().Equal(expectedInterestFactor, currIndexPrior)
// After borrowing again user's borrow balance should have any outstanding interest applied
if snapshot.shouldBorrow {
borrowCoinsBefore, _ := suite.keeper.GetBorrow(snapshotCtx, tc.args.user)
expectedInterestCoins := sdk.NewCoin(tc.args.borrowCoinDenom, expectedInterest)
expectedBorrowCoinsAfter := borrowCoinsBefore.Amount.Add(snapshot.borrowCoin).Add(expectedInterestCoins)
err = suite.keeper.Borrow(snapshotCtx, tc.args.user, sdk.NewCoins(snapshot.borrowCoin))
suite.Require().NoError(err)
borrowCoinsAfter, _ := suite.keeper.GetBorrow(snapshotCtx, tc.args.user)
suite.Require().Equal(expectedBorrowCoinsAfter, borrowCoinsAfter.Amount)
}
// Update previous context to this snapshot's context, segmenting time periods between snapshots
prevCtx = snapshotCtx
}
})
}
}
type ExpectedSupplyInterest struct {
elapsedTime int64
shouldSupply bool
supplyCoin sdk.Coin
}
func (suite *KeeperTestSuite) TestSupplyInterest() {
type args struct {
user sdk.AccAddress
initialSupplierCoins sdk.Coins
initialBorrowerCoins sdk.Coins
initialModuleCoins sdk.Coins
depositCoins sdk.Coins
coinDenoms []string
borrowCoins sdk.Coins
interestRateModel types.InterestRateModel
reserveFactor sdk.Dec
expectedInterestSnaphots []ExpectedSupplyInterest
}
type errArgs struct {
expectPass bool
contains string
}
type interestTest struct {
name string
args args
errArgs errArgs
}
normalModel := types.NewInterestRateModel(sdk.MustNewDecFromStr("0"), sdk.MustNewDecFromStr("0.1"), sdk.MustNewDecFromStr("0.8"), sdk.MustNewDecFromStr("0.5"))
oneDayInSeconds := int64(86400)
oneWeekInSeconds := int64(604800)
oneMonthInSeconds := int64(2592000)
oneYearInSeconds := int64(31536000)
testCases := []interestTest{
{
"one day",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneDayInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one week",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneWeekInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one month",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"one year",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneYearInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"supply/borrow multiple coins",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF)), sdk.NewCoin("bnb", sdk.NewInt(100*BNB_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF)), sdk.NewCoin("bnb", sdk.NewInt(100*BNB_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF)), sdk.NewCoin("bnb", sdk.NewInt(20*BNB_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"supply during snapshot",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneMonthInSeconds,
shouldSupply: true,
supplyCoin: sdk.NewCoin("ukava", sdk.NewInt(20*KAVA_CF)),
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"multiple snapshots",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(80*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
{
"varied snapshots",
args{
user: sdk.AccAddress(crypto.AddressHash([]byte("test"))),
initialBorrowerCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
initialModuleCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(1000*KAVA_CF))),
depositCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(100*KAVA_CF))),
coinDenoms: []string{"ukava"},
borrowCoins: sdk.NewCoins(sdk.NewCoin("ukava", sdk.NewInt(50*KAVA_CF))),
interestRateModel: normalModel,
reserveFactor: sdk.MustNewDecFromStr("0.05"),
expectedInterestSnaphots: []ExpectedSupplyInterest{
{
elapsedTime: oneMonthInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
{
elapsedTime: oneDayInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
{
elapsedTime: oneYearInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
{
elapsedTime: oneWeekInSeconds,
shouldSupply: false,
supplyCoin: sdk.Coin{},
},
},
},
errArgs{
expectPass: true,
contains: "",
},
},
}
for _, tc := range testCases {
suite.Run(tc.name, func() {
// Initialize test app and set context
tApp := app.NewTestApp()
ctx := tApp.NewContext(true, abci.Header{Height: 1, Time: tmtime.Now()})
// Auth module genesis state
authGS := app.NewAuthGenState(
[]sdk.AccAddress{tc.args.user},
[]sdk.Coins{tc.args.initialBorrowerCoins},
)
// Hard module genesis state
hardGS := types.NewGenesisState(types.NewParams(
true,
types.DistributionSchedules{
types.NewDistributionSchedule(true, "ukava", time.Date(2020, 10, 8, 14, 0, 0, 0, time.UTC), time.Date(2020, 11, 22, 14, 0, 0, 0, time.UTC), sdk.NewCoin("hard", sdk.NewInt(5000)), time.Date(2021, 11, 22, 14, 0, 0, 0, time.UTC), types.Multipliers{types.NewMultiplier(types.Small, 0, sdk.MustNewDecFromStr("0.33")), types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.5")), types.NewMultiplier(types.Medium, 24, sdk.OneDec())}),
types.NewDistributionSchedule(true, "bnb", time.Date(2020, 10, 8, 14, 0, 0, 0, time.UTC), time.Date(2020, 11, 22, 14, 0, 0, 0, time.UTC), sdk.NewCoin("hard", sdk.NewInt(5000)), time.Date(2021, 11, 22, 14, 0, 0, 0, time.UTC), types.Multipliers{types.NewMultiplier(types.Small, 0, sdk.MustNewDecFromStr("0.33")), types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.5")), types.NewMultiplier(types.Medium, 24, sdk.OneDec())}),
},
types.DelegatorDistributionSchedules{types.NewDelegatorDistributionSchedule(
types.NewDistributionSchedule(true, "usdx", time.Date(2020, 10, 8, 14, 0, 0, 0, time.UTC), time.Date(2025, 10, 8, 14, 0, 0, 0, time.UTC), sdk.NewCoin("hard", sdk.NewInt(500)), time.Date(2026, 10, 8, 14, 0, 0, 0, time.UTC), types.Multipliers{types.NewMultiplier(types.Small, 0, sdk.MustNewDecFromStr("0.33")), types.NewMultiplier(types.Medium, 6, sdk.MustNewDecFromStr("0.5")), types.NewMultiplier(types.Medium, 24, sdk.OneDec())}),
time.Hour*24,
),
},
types.MoneyMarkets{
types.NewMoneyMarket("ukava",
types.NewBorrowLimit(false, sdk.NewDec(100000000*KAVA_CF), sdk.MustNewDecFromStr("0.8")), // Borrow Limit
"kava:usd", // Market ID
sdk.NewInt(KAVA_CF), // Conversion Factor
sdk.NewInt(USDX_CF*1000), // Auction Size
tc.args.interestRateModel, // Interest Rate Model
tc.args.reserveFactor, // Reserve Factor
sdk.ZeroDec()), // Keeper Reward Percentage
types.NewMoneyMarket("bnb",
types.NewBorrowLimit(false, sdk.NewDec(100000000*BNB_CF), sdk.MustNewDecFromStr("0.8")), // Borrow Limit
"bnb:usd", // Market ID
sdk.NewInt(BNB_CF), // Conversion Factor
sdk.NewInt(USDX_CF*1000), // Auction Size
tc.args.interestRateModel, // Interest Rate Model
tc.args.reserveFactor, // Reserve Factor
sdk.ZeroDec()), // Keeper Reward Percentage
},
0, // LTV counter
), types.DefaultPreviousBlockTime, types.DefaultDistributionTimes)
// Pricefeed module genesis state
pricefeedGS := pricefeed.GenesisState{
Params: pricefeed.Params{
Markets: []pricefeed.Market{
{MarketID: "kava:usd", BaseAsset: "kava", QuoteAsset: "usd", Oracles: []sdk.AccAddress{}, Active: true},
{MarketID: "bnb:usd", BaseAsset: "bnb", QuoteAsset: "usd", Oracles: []sdk.AccAddress{}, Active: true},
},
},
PostedPrices: []pricefeed.PostedPrice{
{
MarketID: "kava:usd",
OracleAddress: sdk.AccAddress{},
Price: sdk.MustNewDecFromStr("2.00"),
Expiry: time.Now().Add(100 * time.Hour),
},
{
MarketID: "bnb:usd",
OracleAddress: sdk.AccAddress{},
Price: sdk.MustNewDecFromStr("20.00"),
Expiry: time.Now().Add(100 * time.Hour),
},
},
}
// Initialize test application
tApp.InitializeFromGenesisStates(authGS,
app.GenesisState{pricefeed.ModuleName: pricefeed.ModuleCdc.MustMarshalJSON(pricefeedGS)},
app.GenesisState{types.ModuleName: types.ModuleCdc.MustMarshalJSON(hardGS)})
// Mint coins to Hard module account
supplyKeeper := tApp.GetSupplyKeeper()
supplyKeeper.MintCoins(ctx, types.ModuleAccountName, tc.args.initialModuleCoins)
keeper := tApp.GetHardKeeper()
suite.app = tApp
suite.ctx = ctx
suite.keeper = keeper
suite.keeper.SetSuppliedCoins(ctx, tc.args.initialModuleCoins)
var err error
// Run begin blocker
hard.BeginBlocker(suite.ctx, suite.keeper)
// // Deposit coins
err = suite.keeper.Deposit(suite.ctx, tc.args.user, tc.args.depositCoins)
suite.Require().NoError(err)
// Borrow coins
err = suite.keeper.Borrow(suite.ctx, tc.args.user, tc.args.borrowCoins)
suite.Require().NoError(err)
// Check interest levels for each snapshot
prevCtx := suite.ctx
for _, snapshot := range tc.args.expectedInterestSnaphots {
for _, coinDenom := range tc.args.coinDenoms {
// ---------------------------- Calculate expected supply interest ----------------------------
// 1. Get cash, borrows, reserves, and borrow index
cashPrior := suite.getModuleAccountAtCtx(types.ModuleName, prevCtx).GetCoins().AmountOf(coinDenom)
var borrowCoinPriorAmount sdk.Int
borrowCoinsPrior, borrowCoinsPriorFound := suite.keeper.GetBorrowedCoins(prevCtx)
suite.Require().True(borrowCoinsPriorFound)
borrowCoinPriorAmount = borrowCoinsPrior.AmountOf(coinDenom)
var supplyCoinPriorAmount sdk.Int
supplyCoinsPrior, supplyCoinsPriorFound := suite.keeper.GetSuppliedCoins(prevCtx)
suite.Require().True(supplyCoinsPriorFound)
supplyCoinPriorAmount = supplyCoinsPrior.AmountOf(coinDenom)
reservesPrior, foundReservesPrior := suite.keeper.GetTotalReserves(prevCtx, coinDenom)
if !foundReservesPrior {
reservesPrior = sdk.NewCoin(coinDenom, sdk.ZeroInt())
}
borrowInterestFactorPrior, foundBorrowInterestFactorPrior := suite.keeper.GetBorrowInterestFactor(prevCtx, coinDenom)
suite.Require().True(foundBorrowInterestFactorPrior)
supplyInterestFactorPrior, foundSupplyInterestFactorPrior := suite.keeper.GetSupplyInterestFactor(prevCtx, coinDenom)
suite.Require().True(foundSupplyInterestFactorPrior)
// 2. Calculate expected borrow interest owed
borrowRateApy, err := hard.CalculateBorrowRate(tc.args.interestRateModel, sdk.NewDecFromInt(cashPrior), sdk.NewDecFromInt(borrowCoinPriorAmount), sdk.NewDecFromInt(reservesPrior.Amount))
suite.Require().NoError(err)
// Convert from APY to SPY, expressed as (1 + borrow rate)
borrowRateSpy, err := hard.APYToSPY(sdk.OneDec().Add(borrowRateApy))
suite.Require().NoError(err)
newBorrowInterestFactor := hard.CalculateBorrowInterestFactor(borrowRateSpy, sdk.NewInt(snapshot.elapsedTime))
expectedBorrowInterest := (newBorrowInterestFactor.Mul(sdk.NewDecFromInt(borrowCoinPriorAmount)).TruncateInt()).Sub(borrowCoinPriorAmount)
expectedReserves := reservesPrior.Add(sdk.NewCoin(coinDenom, sdk.NewDecFromInt(expectedBorrowInterest).Mul(tc.args.reserveFactor).TruncateInt())).Sub(reservesPrior)
expectedTotalReserves := expectedReserves.Add(reservesPrior)
expectedBorrowInterestFactor := borrowInterestFactorPrior.Mul(newBorrowInterestFactor)
expectedSupplyInterest := expectedBorrowInterest.Sub(expectedReserves.Amount)
newSupplyInterestFactor := hard.CalculateSupplyInterestFactor(expectedSupplyInterest.ToDec(), sdk.NewDecFromInt(cashPrior), sdk.NewDecFromInt(borrowCoinPriorAmount), sdk.NewDecFromInt(reservesPrior.Amount))
expectedSupplyInterestFactor := supplyInterestFactorPrior.Mul(newSupplyInterestFactor)
// -------------------------------------------------------------------------------------
// Set up snapshot chain context and run begin blocker
runAtTime := time.Unix(prevCtx.BlockTime().Unix()+(snapshot.elapsedTime), 0)
snapshotCtx := prevCtx.WithBlockTime(runAtTime)
hard.BeginBlocker(snapshotCtx, suite.keeper)
borrowInterestFactor, _ := suite.keeper.GetBorrowInterestFactor(ctx, coinDenom)
suite.Require().Equal(expectedBorrowInterestFactor, borrowInterestFactor)
suite.Require().Equal(expectedBorrowInterest, expectedSupplyInterest.Add(expectedReserves.Amount))
// Check that the total amount of borrowed coins has increased by expected borrow interest amount
borrowCoinsPost, _ := suite.keeper.GetBorrowedCoins(snapshotCtx)
borrowCoinPostAmount := borrowCoinsPost.AmountOf(coinDenom)
suite.Require().Equal(borrowCoinPostAmount, borrowCoinPriorAmount.Add(expectedBorrowInterest))
// Check that the total amount of supplied coins has increased by expected supply interest amount
supplyCoinsPost, _ := suite.keeper.GetSuppliedCoins(prevCtx)
supplyCoinPostAmount := supplyCoinsPost.AmountOf(coinDenom)
suite.Require().Equal(supplyCoinPostAmount, supplyCoinPriorAmount.Add(expectedSupplyInterest))
// Check current total reserves
totalReserves, _ := suite.keeper.GetTotalReserves(snapshotCtx, coinDenom)
suite.Require().Equal(expectedTotalReserves, totalReserves)
// Check that the supply index has increased as expected
currSupplyIndexPrior, _ := suite.keeper.GetSupplyInterestFactor(snapshotCtx, coinDenom)
suite.Require().Equal(expectedSupplyInterestFactor, currSupplyIndexPrior)
// // Check that the borrow index has increased as expected
currBorrowIndexPrior, _ := suite.keeper.GetBorrowInterestFactor(snapshotCtx, coinDenom)
suite.Require().Equal(expectedBorrowInterestFactor, currBorrowIndexPrior)
// After supplying again user's supplied balance should have owed supply interest applied
if snapshot.shouldSupply {
// Calculate percentage of supply interest profits owed to user
userSupplyBefore, _ := suite.keeper.GetDeposit(snapshotCtx, tc.args.user)
userSupplyCoinAmount := userSupplyBefore.Amount.AmountOf(coinDenom)
userPercentOfTotalSupplied := userSupplyCoinAmount.ToDec().Quo(supplyCoinPriorAmount.ToDec())
userExpectedSupplyInterestCoin := sdk.NewCoin(coinDenom, userPercentOfTotalSupplied.MulInt(expectedSupplyInterest).TruncateInt())
// Calculate percentage of borrow interest profits owed to user
userBorrowBefore, _ := suite.keeper.GetBorrow(snapshotCtx, tc.args.user)
userBorrowCoinAmount := userBorrowBefore.Amount.AmountOf(coinDenom)
userPercentOfTotalBorrowed := userBorrowCoinAmount.ToDec().Quo(borrowCoinPriorAmount.ToDec())
userExpectedBorrowInterestCoin := sdk.NewCoin(coinDenom, userPercentOfTotalBorrowed.MulInt(expectedBorrowInterest).TruncateInt())
expectedBorrowCoinsAfter := userBorrowBefore.Amount.Add(userExpectedBorrowInterestCoin)
// Supplying syncs user's owed supply and borrow interest
err = suite.keeper.Deposit(snapshotCtx, tc.args.user, sdk.NewCoins(snapshot.supplyCoin))
suite.Require().NoError(err)
// Fetch user's new borrow and supply balance post-interaction
userSupplyAfter, _ := suite.keeper.GetDeposit(snapshotCtx, tc.args.user)
userBorrowAfter, _ := suite.keeper.GetBorrow(snapshotCtx, tc.args.user)
// Confirm that user's supply index for the denom has increased as expected
var userSupplyAfterIndexFactor sdk.Dec
for _, indexFactor := range userSupplyAfter.Index {
if indexFactor.Denom == coinDenom {
userSupplyAfterIndexFactor = indexFactor.Value
}
}
suite.Require().Equal(userSupplyAfterIndexFactor, currSupplyIndexPrior)
// Check user's supplied amount increased by supply interest owed + the newly supplied coins
expectedSupplyCoinsAfter := userSupplyBefore.Amount.Add(snapshot.supplyCoin).Add(userExpectedSupplyInterestCoin)
suite.Require().Equal(expectedSupplyCoinsAfter, userSupplyAfter.Amount)
// Confirm that user's borrow index for the denom has increased as expected
var userBorrowAfterIndexFactor sdk.Dec
for _, indexFactor := range userBorrowAfter.Index {
if indexFactor.Denom == coinDenom {
userBorrowAfterIndexFactor = indexFactor.Value
}
}
suite.Require().Equal(userBorrowAfterIndexFactor, currBorrowIndexPrior)
// Check user's borrowed amount increased by borrow interest owed
suite.Require().Equal(expectedBorrowCoinsAfter, userBorrowAfter.Amount)
}
prevCtx = snapshotCtx
}
}
})
}
}
func TestInterestTestSuite(t *testing.T) {
suite.Run(t, new(InterestTestSuite))
}