test: migrate Cover integration tests to ethers v6 (#1465)

Author: MilGard91

contracts/mocks/tokens/ERC20Mock.sol

@@ -17,25 +17,21 @@ contract ERC20Mock is ERC20 {
   }
 
   function setMetadata(
-    string memory name,
-    string memory symbol,
-    uint8 __decimals
+    string memory tokenName,
+    string memory tokenSymbol,
+    uint8 tokenDecimals
   ) public {
-    _name = name;
-    _symbol = symbol;
-    _decimals = __decimals;
+    _name = tokenName;
+    _symbol = tokenSymbol;
+    _decimals = tokenDecimals;
   }
 
-  function setName(string memory name) public {
-    _name = name;
+  function name() public view override returns (string memory) {
+    return _name;
   }
 
-  function setSymbol(string memory symbol) public {
-    _symbol = symbol;
-  }
-
-  function setDecimals(uint8 __decimals) public {
-    _decimals = __decimals;
+  function symbol() public view override returns (string memory) {
+    return _symbol;
   }
 
   function decimals() public view override returns (uint8) {

contracts/modules/cover/Cover.sol

@@ -246,7 +246,9 @@ contract Cover is ICover, EIP712, RegistryAware, ReentrancyGuard, Multicall {
     {
       uint nxmPriceInCoverAsset = pool.getInternalTokenPriceInAssetAndUpdateTwap(params.coverAsset);
       uint amountDueInNXM = _createCover(params, poolAllocationRequests, coverId, nxmPriceInCoverAsset);
-      premiumInPaymentAsset = nxmPriceInCoverAsset * amountDueInNXM / ONE_NXM;
+      premiumInPaymentAsset = params.coverAsset == params.paymentAsset
+        ? nxmPriceInCoverAsset * amountDueInNXM / ONE_NXM
+        : amountDueInNXM;
     }
 
     _retrievePayment(

lib/constants.js

@@ -137,13 +137,14 @@ const Assets = {
 
 const PoolAsset = {
   ETH: 0,
-  DAI: 1,
+  DAI: 1, // deprecated
   stETH: 2,
   NXMTY: 3, // NXM Treasury Yield (Enzyme)
   rETH: 4,
   SafeTracker: 5,
   USDC: 6,
   cbBTC: 7,
+  NXM: 255, // used as payment asset but technically not added to Pool assets
 };
 
 const ContractTypes = {

lib/helpers.js

@@ -44,8 +44,23 @@ const waitForInput = query => {
 };
 
 const BigIntMath = {
-  min: (a, b) => (a < b ? a : b),
-  max: (a, b) => (a > b ? a : b),
+  min: (a, b) => {
+    const aBigInt = BigInt(a);
+    const bBigInt = BigInt(b);
+    return aBigInt < bBigInt ? aBigInt : bBigInt;
+  },
+  max: (a, b) => {
+    const aBigInt = BigInt(a);
+    const bBigInt = BigInt(b);
+    return aBigInt > bBigInt ? aBigInt : bBigInt;
+  },
+  divCeil: (a, b) => (BigInt(a) + BigInt(b) - 1n) / BigInt(b),
+  sum: arr => arr.reduce((x, y) => BigInt(x) + BigInt(y), 0n),
+  /**
+   * Round up to the nearest multiple of a given unit
+   * Example: roundUpToMultiple(7n, 3n) = 9n
+   */
+  roundUpToMultiple: (value, unit) => BigIntMath.divCeil(value, unit) * BigInt(unit),
 };
 
 module.exports = {

lib/protocol.js

@@ -1,5 +1,7 @@
 const { ethers } = require('ethers');
 const { parseEther, ZeroAddress } = ethers;
+const { BigIntMath } = require('./helpers');
+const { PoolAsset } = require('./constants');
 
 const COVER_PRICE_DENOMINATOR = 10000n;
 
@@ -33,15 +35,15 @@ function calculateInternalPrice(currentState, observations, capital, supply, cur
 
   const averagePriceB = (currentObservation.priceCumulativeBelow - firstObservation.priceCumulativeBelow) / elapsed;
 
-  const priceA = averagePriceA > spotPriceA ? spotPriceA : averagePriceA;
-  const priceB = averagePriceB > spotPriceB ? averagePriceB : spotPriceB;
+  const priceA = BigIntMath.min(averagePriceA, spotPriceA);
+  const priceB = BigIntMath.max(averagePriceB, spotPriceB);
+  const bookValue = (parseEther('1') * capital) / supply;
 
-  const internalPrice = ((priceA + priceB - parseEther('1')) * capital) / supply;
+  const internalPrice = priceA + priceB - bookValue;
   const maxPrice = (parseEther('1') * 3n * capital) / supply; // 300% BV
   const minPrice = (parseEther('1') * 35n * capital) / (supply * 100n); // 35% BV
 
-  const maxInternalPrice = internalPrice > maxPrice ? internalPrice : maxPrice;
-  return maxInternalPrice > minPrice ? minPrice : maxInternalPrice;
+  return BigIntMath.max(BigIntMath.min(internalPrice, maxPrice), minPrice);
 }
 
 // TODO: eject from lib - we'll clearly not use it outside of tests
@@ -71,6 +73,7 @@ async function getInternalPrice(ramm, pool, tokenController, timestamp) {
       timestamp: observation.timestamp,
     };
   }
+
   const state = {
     nxmA: previousState.nxmA,
     nxmB: previousState.nxmB,
@@ -81,22 +84,23 @@ async function getInternalPrice(ramm, pool, tokenController, timestamp) {
   };
 
   const [currentState] = await ramm._getReserves(state, context, timestamp);
-
   const observations = await ramm._updateTwap(state, previousObservations, context, timestamp);
+
   return calculateInternalPrice(currentState, observations, capital, supply, timestamp, { GRANULARITY, PERIOD_SIZE });
 }
 
 // ======================= COVER ==============================================
 
-function calculatePremium(amount, rate, period, price, allocationUnit) {
+function calculatePremium(amount, rate, period, price, allocationUnit, paymentAsset) {
   const nxmAmount = (amount * parseEther('1')) / rate;
 
   const coverNXMAmount =
     nxmAmount % allocationUnit === 0n ? nxmAmount : (nxmAmount / allocationUnit + 1n) * allocationUnit;
 
-  const premiumInNxm = (((coverNXMAmount * price) / COVER_PRICE_DENOMINATOR) * period) / (365n * 24n * 60n * 60n);
+  const annualizedPremiumNxm = (coverNXMAmount * price) / COVER_PRICE_DENOMINATOR;
+  const premiumInNxm = (annualizedPremiumNxm * BigInt(period)) / (365n * 24n * 60n * 60n);
 
-  const premiumInAsset = (premiumInNxm * rate) / parseEther('1');
+  const premiumInAsset = paymentAsset === PoolAsset.NXM ? premiumInNxm : (premiumInNxm * rate) / parseEther('1');
 
   return { premiumInNxm, premiumInAsset, coverNXMAmount };
 }

release/3.0/config/deployments.json

@@ -104,8 +104,8 @@
     "salt": 2295602
   },
   "Cover": {
-    "expectedAddress": "0xcafea6DcD8Ef5836E300b4E62E9a90975b0477EA",
-    "salt": 15283923,
+    "expectedAddress": "0xcafea49C5a4aBae7731092B95a0B3590e3753891",
+    "salt": 22678373,
     "constructorArgs": [
       "0xcafea2c575550512582090AA06d0a069E7236b9e",
       "0xcafeade1872f14adc0a03Ec7b0088b61D76ec729",

release/3.0/release-3.0.md

@@ -114,8 +114,8 @@ ENABLE_OPTIMIZER=1 npx hardhat verify --network mainnet \
   * _stakingPoolImplementation = `0xcafeade1872f14adc0a03Ec7b0088b61D76ec729`
   * _verifyingAddress = `0xcafeac0fF5dA0A2777d915531bfA6B29d282Ee62`
 * Address brute force command
-  * Address: `0xcafea6DcD8Ef5836E300b4E62E9a90975b0477EA`
-  * Salt: 15283923
+  * Address: `0xcafea4A986A8d88dc63095034cE36bC8387A8534`
+  * Salt: 2295602
 ```bash
 ENABLE_OPTIMIZER=1 node scripts/create2/find-salt.js \
   -t cafea \