feat(flash-swap): support liquidating vaults with underlying as collateral

.github/workflows/deploy-hifi-flash-uniswap-v2.yaml → .github/workflows/deploy-collateral-flash-uniswap-v2.yaml

@@ -1,4 +1,4 @@
-name: "Deploy: HifiFlashUniswapV2"
+name: "Deploy: CollateralFlashUniswapV2"
 
 env:
   ETHERSCAN_API_KEY: ${{ secrets.ETHERSCAN_API_KEY }}
@@ -56,7 +56,7 @@ jobs:
       - name: "Build the TypeChain bindings"
         run: "yarn build:types"
 
-      - name: "Deploy HifiFlashUniswapV2"
+      - name: "Deploy CollateralFlashUniswapV2"
         id: deploy
         run: >-
           yarn workspace @hifi/tasks hardhat
@@ -67,7 +67,7 @@ jobs:
           --confirmations "${{ github.event.inputs.confirmations }}"
           --set-output true
 
-      - name: "Verify HifiFlashUniswapV2"
+      - name: "Verify CollateralFlashUniswapV2"
         run: >-
           yarn workspace @hifi/flash-swap hardhat
           verify "${{ steps.deploy.outputs.hifi-flash-uniswap-v2 }}" --network "${{ github.event.inputs.chain }}"

.github/workflows/deploy-underlying-flash-uniswap-v2.yaml

@@ -0,0 +1,76 @@
+name: "Deploy: UnderlyingFlashUniswapV2"
+
+env:
+  ETHERSCAN_API_KEY: ${{ secrets.ETHERSCAN_API_KEY }}
+  INFURA_API_KEY: ${{ secrets.INFURA_API_KEY }}
+  MNEMONIC: ${{ secrets.MNEMONIC }}
+
+on:
+  workflow_dispatch:
+    inputs:
+      balance-sheet:
+        description: "Address of the BalanceSheet contract"
+        required: true
+      chain:
+        description: "Chain name in lowercase"
+        required: true
+      confirmations:
+        default: "2"
+        description: "Number of block confirmations to wait before attempting verification"
+        required: false
+      ref:
+        default: "main"
+        description: "Git ref to checkout"
+        required: false
+      uni-v2-factory:
+        description: "Address of the UniswapV2Factory contract"
+        required: true
+      uni-v2-pair-init-code-hash:
+        description: "Init code hash of the UniswapV2Pair contract"
+        required: true
+
+jobs:
+  deploy-and-verify:
+    runs-on: "ubuntu-latest"
+    steps:
+      - name: "Check out the repo"
+        uses: "actions/checkout@v2"
+        with:
+          ref: ${{ github.event.inputs.ref }}
+
+      - name: "Setup Node.js"
+        uses: "actions/setup-node@v2"
+        with:
+          cache: "yarn"
+          node-version: "16"
+
+      - name: "Install the dependencies"
+        run: "yarn install --immutable"
+
+      - name: "Build the TypeScript packages"
+        run: "yarn build"
+
+      - name: "Compile the contracts and generate TypeChain bindings"
+        run: "yarn compile:sol"
+
+      - name: "Build the TypeChain bindings"
+        run: "yarn build:types"
+
+      - name: "Deploy UnderlyingFlashUniswapV2"
+        id: deploy
+        run: >-
+          yarn workspace @hifi/tasks hardhat
+          deploy:contract:hifi-flash-uniswap-v2 --network "${{ github.event.inputs.chain }}"
+          --balance-sheet "${{ github.event.inputs.balance-sheet }}"
+          --uni-v2-factory "${{ github.event.inputs.uni-v2-factory }}"
+          --uni-v2-pair-init-code-hash "${{ github.event.inputs.uni-v2-pair-init-code-hash }}"
+          --confirmations "${{ github.event.inputs.confirmations }}"
+          --set-output true
+
+      - name: "Verify UnderlyingFlashUniswapV2"
+        run: >-
+          yarn workspace @hifi/flash-swap hardhat
+          verify "${{ steps.deploy.outputs.hifi-flash-uniswap-v2 }}" --network "${{ github.event.inputs.chain }}"
+          "${{ github.event.inputs.balance-sheet }}"
+          "${{ github.event.inputs.uni-v2-factory }}"
+          "${{ github.event.inputs.uni-v2-pair-init-code-hash }}"

packages/errors/src/flashSwap.ts

@@ -1,12 +1,12 @@
-export enum HifiFlashUniswapV2Errors {
-  CallNotAuthorized = "HifiFlashUniswapV2__CallNotAuthorized",
-  FlashBorrowCollateral = "HifiFlashUniswapV2__FlashBorrowCollateral",
-  InsufficientProfit = "HifiFlashUniswapV2__InsufficientProfit",
-  UnderlyingNotInPool = "HifiFlashUniswapV2__UnderlyingNotInPool",
+export enum CollateralFlashUniswapV2Errors {
+  CallNotAuthorized = "CollateralFlashUniswapV2__CallNotAuthorized",
+  FlashBorrowCollateral = "CollateralFlashUniswapV2__FlashBorrowCollateral",
+  InsufficientProfit = "CollateralFlashUniswapV2__InsufficientProfit",
+  UnderlyingNotInPool = "CollateralFlashUniswapV2__UnderlyingNotInPool",
 }
 
-export enum HifiFlashUniswapV2UnderlyingErrors {
-  CallNotAuthorized = "HifiFlashUniswapV2Underlying__CallNotAuthorized",
-  FlashBorrowWrongToken = "HifiFlashUniswapV2Underlying__FlashBorrowWrongToken",
-  UnderlyingNotInPool = "HifiFlashUniswapV2Underlying__UnderlyingNotInPool",
+export enum UnderlyingFlashUniswapV2Errors {
+  CallNotAuthorized = "UnderlyingFlashUniswapV2__CallNotAuthorized",
+  FlashBorrowWrongToken = "UnderlyingFlashUniswapV2__FlashBorrowWrongToken",
+  UnderlyingNotInPool = "UnderlyingFlashUniswapV2__UnderlyingNotInPool",
 }

packages/errors/src/index.ts

@@ -5,7 +5,7 @@ export { HifiPoolErrors, HifiPoolRegistryErrors, YieldSpaceErrors } from "./amm"
 export { OwnableErrors } from "./external";
 
 // flashSwap.ts
-export { HifiFlashUniswapV2Errors, HifiFlashUniswapV2UnderlyingErrors } from "./flashSwap";
+export { CollateralFlashUniswapV2Errors, UnderlyingFlashUniswapV2Errors } from "./flashSwap";
 
 // protocol.ts
 export {

packages/flash-swap/.gitignore

@@ -1,16 +1,20 @@
 # types
 src/types/*
 !src/types/Erc20.d.ts
-!src/types/HifiFlashUniswapV2.d.ts
+!src/types/CollateralFlashUniswapV2.d.ts
+!src/types/ICollateralFlashUniswapV2.d.ts
 !src/types/IErc20.d.ts
-!src/types/IHifiFlashUniswapV2.d.ts
+!src/types/IUnderlyingFlashUniswapV2.d.ts
 !src/types/IUniswapV2Callee.d.ts
 !src/types/IUniswapV2Pair.d.ts
+!src/types/UnderlyingFlashUniswapV2.d.ts
 !src/types/UniswapV2Pair.d.ts
 !src/types/factories/Erc20__factory.ts
-!src/types/factories/HifiFlashUniswapV2__factory.ts
+!src/types/factories/CollateralFlashUniswapV2__factory.ts
 !src/types/factories/IErc20__factory.ts
-!src/types/factories/IHifiFlashUniswapV2__factory.ts
+!src/types/factories/ICollateralFlashUniswapV2__factory.ts
+!src/types/factories/IUnderlyingFlashUniswapV2__factory.ts
 !src/types/factories/IUniswapV2Callee__factory.ts
 !src/types/factories/IUniswapV2Pair__factory.ts
+!src/types/factories/UnderlyingFlashUniswapV2__factory.ts
 !src/types/factories/UniswapV2Pair__factory.ts

packages/flash-swap/README.md

@@ -28,8 +28,9 @@ themselves; the latter, the smart contract ABIs and the TypeChain bindings.
 
 You are not supposed to import the smart contracts. Instead, you should interact with the Uniswap pool
 directly. For example, with the [UniswapV2Pair](https://github.com/Uniswap/v2-core/blob/v1.0.1/contracts/UniswapV2Pair.sol)
-contract you would call the `swap` function. Then Uniswap will forward the call to `HifiFlashUniswapV2`. You can read more about flash
-swaps work in Uniswap on [docs.uniswap.org](https://docs.uniswap.org/protocol/V2/concepts/core-concepts/flash-swaps).
+contract you would call the `swap` function. Then, Uniswap will forward the call to the `CollateralFlashUniswapV2`
+contract. You can read more about flash swaps work in Uniswap on
+[docs.uniswap.org](https://docs.uniswap.org/protocol/V2/concepts/core-concepts/flash-swaps).
 
 ### JavaScript
 
@@ -41,13 +42,13 @@ import { getDefaultProvider } from "@ethersproject/providers";
 import { parseUnits } from "@ethersproject/units";
 import type { UniswapV2Pair__factory } from "@hifi/flash-swap/dist/types/factories/UniswapV2Pair__factory";
 
-async function flashSwap() {
+async function collateralFlashSwap() {
   const defaultProvider = getDefaultProvider();
   const pair = UniswapV2Pair__factory("0x...", defaultProvider);
 
   const token0Amount = parseUnits("100", 18);
   const token1Amount = parseUnits("0", 18);
-  const to = "0x..."; // Address of HifiFlashUniswapV2, get it from https://docs.hifi.finance
+  const to = "0x..."; // Address of CollateralFlashUniswapV2, get it from https://docs.hifi.finance
 
   const borrower = "0x...";
   const hToken = "0x...";

packages/flash-swap/contracts/uniswap-v2/HifiFlashUniswapV2.sol → packages/flash-swap/contracts/uniswap-v2/CollateralFlashUniswapV2.sol

@@ -7,40 +7,45 @@ import "@hifi/protocol/contracts/core/balanceSheet/IBalanceSheetV1.sol";
 import "@hifi/protocol/contracts/core/balanceSheet/SBalanceSheetV1.sol";
 import "@hifi/protocol/contracts/core/hToken/IHToken.sol";
 
-import "./HifiFlashUniswapV2Utils.sol";
-import "./IHifiFlashUniswapV2.sol";
+import "./FlashUtils.sol";
+import "./ICollateralFlashUniswapV2.sol";
 import "./IUniswapV2Pair.sol";
 
 /// @notice Emitted when the caller is not the Uniswap V2 pair contract.
-error HifiFlashUniswapV2__CallNotAuthorized(address caller);
+error CollateralFlashUniswapV2__CallNotAuthorized(address caller);
 
 /// @notice Emitted when the flash borrowed asset is the collateral instead of the underlying.
-error HifiFlashUniswapV2__FlashBorrowCollateral(uint256 collateralAmount);
+error CollateralFlashUniswapV2__FlashBorrowCollateral(uint256 collateralAmount);
 
 /// @notice Emitted when the liquidation does not yield a sufficient profit.
-error HifiFlashUniswapV2__InsufficientProfit(
+error CollateralFlashUniswapV2__InsufficientProfit(
     uint256 seizedCollateralAmount,
     uint256 repayCollateralAmount,
     uint256 minProfit
 );
 
 /// @notice Emitted when neither the token0 nor the token1 is the underlying.
-error HifiFlashUniswapV2__UnderlyingNotInPool(IUniswapV2Pair pair, address token0, address token1, IErc20 underlying);
+error CollateralFlashUniswapV2__UnderlyingNotInPool(
+    IUniswapV2Pair pair,
+    address token0,
+    address token1,
+    IErc20 underlying
+);
 
-/// @title HifiFlashUniswapV2
+/// @title CollateralFlashUniswapV2
 /// @author Hifi
-contract HifiFlashUniswapV2 is IHifiFlashUniswapV2 {
+contract CollateralFlashUniswapV2 is ICollateralFlashUniswapV2 {
     using SafeErc20 for IErc20;
 
     /// PUBLIC STORAGE ///
 
-    /// @inheritdoc IHifiFlashUniswapV2
+    /// @inheritdoc ICollateralFlashUniswapV2
     IBalanceSheetV1 public override balanceSheet;
 
-    /// @inheritdoc IHifiFlashUniswapV2
+    /// @inheritdoc ICollateralFlashUniswapV2
     address public override uniV2Factory;
 
-    /// @inheritdoc IHifiFlashUniswapV2
+    /// @inheritdoc ICollateralFlashUniswapV2
     bytes32 public override uniV2PairInitCodeHash;
 
     /// CONSTRUCTOR ///
@@ -56,7 +61,7 @@ contract HifiFlashUniswapV2 is IHifiFlashUniswapV2 {
 
     /// PUBLIC CONSTANT FUNCTIONS ////
 
-    /// @inheritdoc IHifiFlashUniswapV2
+    /// @inheritdoc ICollateralFlashUniswapV2
     function getCollateralAndUnderlyingAmount(
         IUniswapV2Pair pair,
         uint256 amount0,
@@ -67,22 +72,22 @@ contract HifiFlashUniswapV2 is IHifiFlashUniswapV2 {
         address token1 = pair.token1();
         if (token0 == address(underlying)) {
             if (amount1 > 0) {
-                revert HifiFlashUniswapV2__FlashBorrowCollateral(amount1);
+                revert CollateralFlashUniswapV2__FlashBorrowCollateral(amount1);
             }
             collateral = IErc20(token1);
             underlyingAmount = amount0;
         } else if (token1 == address(underlying)) {
             if (amount0 > 0) {
-                revert HifiFlashUniswapV2__FlashBorrowCollateral(amount0);
+                revert CollateralFlashUniswapV2__FlashBorrowCollateral(amount0);
             }
             collateral = IErc20(token0);
             underlyingAmount = amount1;
         } else {
-            revert HifiFlashUniswapV2__UnderlyingNotInPool(pair, token0, token1, underlying);
+            revert CollateralFlashUniswapV2__UnderlyingNotInPool(pair, token0, token1, underlying);
         }
     }
 
-    /// @inheritdoc IHifiFlashUniswapV2
+    /// @inheritdoc ICollateralFlashUniswapV2
     function getRepayCollateralAmount(
         IUniswapV2Pair pair,
         IErc20 underlying,
@@ -146,19 +151,14 @@ contract HifiFlashUniswapV2 is IHifiFlashUniswapV2 {
         // Check that the caller is a genuine UniswapV2Pair contract.
         if (
             msg.sender !=
-            HifiFlashUniswapV2Utils.pairFor(
-                uniV2Factory,
-                uniV2PairInitCodeHash,
-                address(vars.underlying),
-                address(vars.collateral)
-            )
+            FlashUtils.pairFor(uniV2Factory, uniV2PairInitCodeHash, address(vars.underlying), address(vars.collateral))
         ) {
-            revert HifiFlashUniswapV2__CallNotAuthorized(msg.sender);
+            revert CollateralFlashUniswapV2__CallNotAuthorized(msg.sender);
         }
 
         // Mint hTokens and liquidate the borrower.
-        vars.mintedHTokenAmount = HifiFlashUniswapV2Utils.mintHTokensInternal(vars.bond, vars.underlyingAmount);
-        vars.seizedCollateralAmount = HifiFlashUniswapV2Utils.liquidateBorrowInternal(
+        vars.mintedHTokenAmount = FlashUtils.mintHTokensInternal(vars.bond, vars.underlyingAmount);
+        vars.seizedCollateralAmount = FlashUtils.liquidateBorrowInternal(
             balanceSheet,
             vars.borrower,
             vars.bond,
@@ -173,7 +173,7 @@ contract HifiFlashUniswapV2 is IHifiFlashUniswapV2 {
             vars.underlyingAmount
         );
         if (vars.seizedCollateralAmount <= vars.repayCollateralAmount + vars.minProfit) {
-            revert HifiFlashUniswapV2__InsufficientProfit(
+            revert CollateralFlashUniswapV2__InsufficientProfit(
                 vars.seizedCollateralAmount,
                 vars.repayCollateralAmount,
                 vars.minProfit

packages/flash-swap/contracts/uniswap-v2/HifiFlashUniswapV2Utils.sol → packages/flash-swap/contracts/uniswap-v2/FlashUtils.sol

@@ -4,13 +4,9 @@ pragma solidity >=0.8.4;
 import "@paulrberg/contracts/token/erc20/IErc20.sol";
 import "@hifi/protocol/contracts/core/balanceSheet/IBalanceSheetV1.sol";
 
-/// @title HifiFlashUniswapV2
+/// @title FlashUtils
 /// @author Hifi
-library HifiFlashUniswapV2Utils {
-    /// @dev The init code hash of the UniswapV2Pair contract. The same for all Uniswap v2 deployments.
-    bytes32 public constant UNI_V2_PAIR_INIT_CODE_HASH =
-        0x96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f;
-
+library FlashUtils {
     /// @dev Calculates the CREATE2 address for a pair without making any external calls.
     function pairFor(
         address uniV2Factory,

packages/flash-swap/contracts/uniswap-v2/IHifiFlashUniswapV2.sol → packages/flash-swap/contracts/uniswap-v2/ICollateralFlashUniswapV2.sol

@@ -6,10 +6,11 @@ import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Callee.sol";
 
 import "./IUniswapV2Pair.sol";
 
-/// @title IHifiFlashUniswapV2
+/// @title ICollateralFlashUniswapV2
 /// @author Hifi
 /// @notice Integration of Uniswap V2 flash swaps for liquidating underwater accounts in Hifi.
-interface IHifiFlashUniswapV2 is IUniswapV2Callee {
+/// that are collateralized with non-underlying tokens.
+interface ICollateralFlashUniswapV2 is IUniswapV2Callee {
     /// EVENTS ///
 
     event FlashLiquidateBorrow(

packages/flash-swap/contracts/uniswap-v2/IHifiFlashUniswapV2Underlying.sol → packages/flash-swap/contracts/uniswap-v2/IUnderlyingFlashUniswapV2.sol

@@ -6,11 +6,11 @@ import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Callee.sol";
 
 import "./IUniswapV2Pair.sol";
 
-/// @title IHifiFlashUniswapV2Underlying
+/// @title IUnderlyingFlashUniswapV2
 /// @author Hifi
 /// @notice Integration of Uniswap V2 flash swaps for liquidating underwater accounts in Hifi
 /// that are collateralized with underlying tokens.
-interface IHifiFlashUniswapV2Underlying is IUniswapV2Callee {
+interface IUnderlyingFlashUniswapV2 is IUniswapV2Callee {
     /// EVENTS ///
 
     event FlashLiquidateBorrow(