Refactored 'withdraw' function: replaced array argument with a single uint256

Author: KyrylR

contracts/contracts/Depositor.sol

@@ -4,7 +4,7 @@ pragma solidity 0.8.23;
 import {Address} from "@openzeppelin/contracts/utils/Address.sol";
 
 library PoseidonUnit4L {
-    function poseidon(bytes32[4] calldata) public pure returns (bytes32) {}
+    function poseidon(uint256[4] calldata) public pure returns (uint256) {}
 }
 
 /**
@@ -72,12 +72,7 @@ contract Depositor {
      * @param secret The secret used to withdraw the deposit.
      * @param secretHash The Poseidon hash of the secret used to create the deposit.
      */
-    event Withdrawn(
-        address indexed recipient,
-        uint256 amount,
-        bytes32[4] secret,
-        bytes32 secretHash
-    );
+    event Withdrawn(address indexed recipient, uint256 amount, uint256 secret, bytes32 secretHash);
 
     /**
      * @notice Emitted when deposited funds are restored to the sender after the lock time has expired.
@@ -160,8 +155,8 @@ contract Depositor {
      *      Uses the PoseidonUnit1L library to hash the provided secret.
      * @param secret_ The prototype of the `secretHash` used in the deposit function.
      */
-    function withdraw(bytes32[4] calldata secret_) external {
-        bytes32 secretHash_ = PoseidonUnit4L.poseidon(secret_);
+    function withdraw(uint256 secret_) external {
+        bytes32 secretHash_ = _getSecretHash(secret_);
 
         Deposit storage userDeposit = deposits[secretHash_];
 
@@ -206,4 +201,13 @@ contract Depositor {
 
         emit Restored(userDeposit.sender, depositAmount_, secretHash_);
     }
+
+    function _getSecretHash(uint256 secret_) private pure returns (bytes32) {
+        uint256 part1 = secret_ >> 192;
+        uint256 part2 = ((secret_ >> 128) & 0xFFFFFFFFFFFFFFFF);
+        uint256 part3 = ((secret_ >> 64) & 0xFFFFFFFFFFFFFFFF);
+        uint256 part4 = (secret_ & 0xFFFFFFFFFFFFFFFF);
+
+        return bytes32(PoseidonUnit4L.poseidon([part1, part2, part3, part4]));
+    }
 }

contracts/test/Depositor.test.ts

@@ -8,7 +8,7 @@ import { increase } from "@nomicfoundation/hardhat-network-helpers/dist/src/help
 
 import { Depositor } from "@ethers-v6";
 
-import { Reverter, poseidonHash, getPoseidon } from "@utils";
+import { Reverter, getPoseidon } from "@utils";
 import { impersonateAccount, setBalance, time } from "@nomicfoundation/hardhat-network-helpers";
 
 describe("Taprootized Atomic Swaps", () => {
@@ -38,16 +38,14 @@ describe("Taprootized Atomic Swaps", () => {
 
   afterEach(reverter.revert);
 
-  function generateSecret(): [string[], string] {
-    const part1 = ethers.hexlify(ethers.randomBytes(8));
-    const part2 = ethers.hexlify(ethers.randomBytes(8));
-    const part3 = ethers.hexlify(ethers.randomBytes(8));
-    const part4 = ethers.hexlify(ethers.randomBytes(8));
+  function generateSecret(): [string, string] {
+    const parts = [1, 2, 3, 4].map(() => ethers.hexlify(ethers.randomBytes(8)));
+    const wholeSecret = "0x" + parts.map((hexString: string) => hexString.replace("0x", "")).join("");
 
-    const inputs = [part1, part2, part3, part4].map((v) => BigInt(v));
+    const inputs = parts.map((v) => BigInt(v));
     const secretHash = ethers.toBeHex(Poseidon.hash(inputs), 32);
 
-    return [inputs.map((v) => ethers.toBeHex(v, 32)), secretHash];
+    return [wholeSecret, secretHash];
   }
 
   it("should deposit ETH with correct details", async () => {
@@ -80,7 +78,7 @@ describe("Taprootized Atomic Swaps", () => {
   });
 
   it("should revert if trying to deposit with same secret hash", async () => {
-    const [secret, secretHash] = generateSecret();
+    const [, secretHash] = generateSecret();
 
     await depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
@@ -90,15 +88,15 @@ describe("Taprootized Atomic Swaps", () => {
   });
 
   it("should reject deposit to zero address", async () => {
-    const [secret, secretHash] = generateSecret();
+    const [, secretHash] = generateSecret();
 
     await expect(
       depositor.deposit(ethers.ZeroAddress, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT })
     ).to.be.revertedWithCustomError(depositor, "ZeroAddressNotAllowed");
   });
 
   it("should reject deposit with insufficient amount", async () => {
-    const [secret, secretHash] = generateSecret();
+    const [, secretHash] = generateSecret();
 
     await expect(depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: 0 })).to.be.revertedWithCustomError(
       depositor,
@@ -112,7 +110,7 @@ describe("Taprootized Atomic Swaps", () => {
 
     await depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
-    await expect(depositor.withdraw([incorrectSecret[0], incorrectSecret[1], incorrectSecret[2], incorrectSecret[3]]))
+    await expect(depositor.withdraw(incorrectSecret))
       .to.be.revertedWithCustomError(depositor, "DepositDoesNotExist")
       .withArgs(incorrectSecretHash);
   });
@@ -122,7 +120,7 @@ describe("Taprootized Atomic Swaps", () => {
 
     await depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
-    await expect(depositor.withdraw([secret[0], secret[1], secret[2], secret[3]]))
+    await expect(depositor.withdraw(secret))
       .to.emit(depositor, "Withdrawn")
       .withArgs(USER2.address, DEPOSIT_AMOUNT, secret, secretHash);
   });
@@ -132,9 +130,9 @@ describe("Taprootized Atomic Swaps", () => {
 
     await depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
-    await depositor.withdraw([secret[0], secret[1], secret[2], secret[3]]);
+    await depositor.withdraw(secret);
 
-    await expect(depositor.withdraw([secret[0], secret[1], secret[2], secret[3]]))
+    await expect(depositor.withdraw(secret))
       .to.be.revertedWithCustomError(depositor, "DepositAlreadyWithdrawn")
       .withArgs(secretHash);
   });
@@ -144,14 +142,11 @@ describe("Taprootized Atomic Swaps", () => {
 
     await depositor.deposit(await depositor.getAddress(), secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
-    await expect(depositor.withdraw([secret[0], secret[1], secret[2], secret[3]])).to.be.revertedWithCustomError(
-      depositor,
-      "FailedInnerCall"
-    );
+    await expect(depositor.withdraw(secret)).to.be.revertedWithCustomError(depositor, "FailedInnerCall");
   });
 
   it("should reject restoring before lock time expires", async () => {
-    const [secret, secretHash] = generateSecret();
+    const [, secretHash] = generateSecret();
 
     const nextBlockTimestamp = (await time.latest()) + 1;
     await time.setNextBlockTimestamp(nextBlockTimestamp);
@@ -172,7 +167,7 @@ describe("Taprootized Atomic Swaps", () => {
   });
 
   it("should reject restoring if the ETH transfer fails", async () => {
-    const [secret, secretHash] = generateSecret();
+    const [, secretHash] = generateSecret();
 
     await impersonateAccount(await depositor.getAddress());
     const depositorAsSigner = await ethers.getSigner(await depositor.getAddress());
@@ -190,7 +185,7 @@ describe("Taprootized Atomic Swaps", () => {
 
     await depositor.deposit(USER2.address, secretHash, LOCK_TIME, { value: DEPOSIT_AMOUNT });
 
-    await depositor.withdraw([secret[0], secret[1], secret[2], secret[3]]);
+    await depositor.withdraw(secret);
 
     await increase(LOCK_TIME);