cleanup and refactoring

contracts/mixins/SelfdestructEthSender.sol

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.25;
+
+
+abstract contract SelfdestructEthSender {
+    constructor() {
+        // tload is done to verify that the EVM is cancun-compatible
+        assembly ("memory-safe") {
+            pop(tload(0))
+        }
+    }
+
+    function stopAndTransferBalance(address payable receiver) external {
+        selfdestruct(receiver);
+    }
+}

contracts/mocks/CheapEthSenderMock.sol → contracts/mocks/SelfdestructEthSenderMock.sol

@@ -2,16 +2,14 @@
 
 pragma solidity ^0.8.25;
 
-import "../CheapEthSender.sol";
+import "../mixins/SelfdestructEthSender.sol";
 
-contract CheapEthSenderMock is CheapEthSender {
+contract SelfdestructEthSenderMock is SelfdestructEthSender {
     error ETHTransferFailed();
 
-    function alive() external pure returns(uint256) {
-        return 1;
-    }
+    receive() external payable {}
 
-    function sendEthers(address payable receiver) external payable {
+    function transferBalance(address payable receiver) external payable {
         // solhint-disable-next-line avoid-low-level-calls
         (bool success, ) = receiver.call{value: address(this).balance}("");
         if (!success) revert ETHTransferFailed();

test/contracts/CheapEthSender.test.ts → test/contracts/SelfdestructEthSender.test.ts

@@ -4,7 +4,7 @@ import { SignerWithAddress } from '@nomicfoundation/hardhat-ethers/signers';
 import { loadFixture } from '@nomicfoundation/hardhat-network-helpers';
 import { ethers } from 'hardhat';
 
-describe('CheapEthSender', function () {
+describe('SelfdestructEthSender', function () {
     let signer0: SignerWithAddress;
     let signer1: SignerWithAddress;
 
@@ -13,26 +13,26 @@ describe('CheapEthSender', function () {
     });
 
     async function deployMocks() {
-        const CheapEthSender = await ethers.getContractFactory('CheapEthSenderMock');
-        const cheapEthSender = await CheapEthSender.deploy();
+        const EthSender = await ethers.getContractFactory('SelfdestructEthSenderMock');
+        const ethSender = await EthSender.deploy();
 
-        return { cheapEthSender };
+        return { ethSender };
     }
 
     it('should send Ethers with selfdestruct', async function () {
-        const { cheapEthSender } = await loadFixture(deployMocks);
-        const cheapEthSenderAddress = await cheapEthSender.getAddress();
+        const { ethSender } = await loadFixture(deployMocks);
+        const ethSenderAddress = await ethSender.getAddress();
 
-        await signer0.sendTransaction({ to: cheapEthSenderAddress, value: ether('1') });
-        const receipt0 = await (await cheapEthSender.sendEthers(signer1.address)).wait();
+        await signer0.sendTransaction({ to: ethSenderAddress, value: ether('1') });
+        const receipt0 = await (await ethSender.transferBalance(signer1.address)).wait();
         console.log('send ethers without selfdestruct', receipt0!.gasUsed.toString());
 
-        await signer0.sendTransaction({ to: cheapEthSenderAddress, value: ether('1') });
+        await signer0.sendTransaction({ to: ethSenderAddress, value: ether('1') });
         const balanceOfAddr1 = await ethers.provider.getBalance(signer1.address);
-        const receipt1 = await (await cheapEthSender.sendAllEthers(signer1.address)).wait();
+        const receipt1 = await (await ethSender.stopAndTransferBalance(signer1.address)).wait();
         console.log('send all ethers', receipt1!.gasUsed.toString());
         expect(await ethers.provider.getBalance(signer1.address)).to.be.eq(balanceOfAddr1 + ether('1'));
-        expect(await ethers.provider.getBalance(cheapEthSenderAddress)).to.be.eq(ether('0'));
-        expect(await cheapEthSender.alive()).to.be.eq(1n);
+        expect(await ethers.provider.getBalance(ethSenderAddress)).to.be.eq(ether('0'));
+        expect(await ethers.provider.getCode(ethSenderAddress)).to.be.not.eq('0x');
     });
 });