maint(ct): clean up L2xDM tests (#2475)

Cleans up the L2CrossDomainMessenger tests in the same manner as
previous cleanup PRs.
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

packages/contracts/test/contracts/L2/messaging/L2CrossDomainMessenger.spec.ts

-/* External Imports */
-import hre, { ethers } from 'hardhat'
-import { Signer, ContractFactory, Contract } from 'ethers'
+import { ethers } from 'hardhat'
+import { Contract } from 'ethers'
 import { applyL1ToL2Alias } from '@eth-optimism/core-utils'
-import {
-  smock,
-  MockContractFactory,
-  FakeContract,
-} from '@defi-wonderland/smock'
+import { smock, FakeContract, MockContract } from '@defi-wonderland/smock'
+import { SignerWithAddress } from '@nomiclabs/hardhat-ethers/signers'
 
-/* Internal Imports */
 import { expect } from '../../../setup'
+import { predeploys } from '../../../../src'
 import {
+  impersonate,
+  deploy,
   NON_NULL_BYTES32,
   NON_ZERO_ADDRESS,
   encodeXDomainCalldata,
 } from '../../../helpers'
-import { predeploys } from '../../../../src'
 
 describe('L2CrossDomainMessenger', () => {
-  let signer: Signer
+  let signer: SignerWithAddress
   before(async () => {
     ;[signer] = await ethers.getSigners()
   })
@@ -37,49 +34,27 @@ describe('L2CrossDomainMessenger', () => {
     )
   })
 
-  let impersonatedL1CrossDomainMessengerSender: Signer
-  before(async () => {
-    const impersonatedAddress = applyL1ToL2Alias(
-      Fake__L1CrossDomainMessenger.address
-    )
-    await hre.network.provider.request({
-      method: 'hardhat_impersonateAccount',
-      params: [impersonatedAddress],
-    })
-    await hre.network.provider.request({
-      method: 'hardhat_setBalance',
-      params: [impersonatedAddress, '0xFFFFFFFFFFFFFFFFF'],
-    })
-    impersonatedL1CrossDomainMessengerSender = await ethers.getSigner(
-      impersonatedAddress
-    )
-  })
-
-  let Factory__L2CrossDomainMessenger: ContractFactory
+  let impersonatedL1CrossDomainMessengerSender: SignerWithAddress
   before(async () => {
-    Factory__L2CrossDomainMessenger = await ethers.getContractFactory(
-      'L2CrossDomainMessenger'
+    impersonatedL1CrossDomainMessengerSender = await impersonate(
+      applyL1ToL2Alias(Fake__L1CrossDomainMessenger.address),
+      '0xFFFFFFFFFFFFFFFFF'
     )
   })
 
   let L2CrossDomainMessenger: Contract
   beforeEach(async () => {
-    L2CrossDomainMessenger = await Factory__L2CrossDomainMessenger.deploy(
-      Fake__L1CrossDomainMessenger.address
-    )
+    L2CrossDomainMessenger = await deploy('L2CrossDomainMessenger', {
+      args: [Fake__L1CrossDomainMessenger.address],
+    })
   })
 
   describe('xDomainMessageSender', () => {
-    let Mock__Factory__L2CrossDomainMessenger: MockContractFactory<ContractFactory>
-    let Mock__L2CrossDomainMessenger
+    let Mock__L2CrossDomainMessenger: MockContract<Contract>
     before(async () => {
-      Mock__Factory__L2CrossDomainMessenger = await smock.mock(
-        'L2CrossDomainMessenger'
-      )
-      Mock__L2CrossDomainMessenger =
-        await Mock__Factory__L2CrossDomainMessenger.deploy(
-          Fake__L1CrossDomainMessenger.address
-        )
+      Mock__L2CrossDomainMessenger = await (
+        await smock.mock('L2CrossDomainMessenger')
+      ).deploy(Fake__L1CrossDomainMessenger.address)
     })
 
     it('should return the xDomainMsgSender address', async () => {
@@ -87,6 +62,7 @@ describe('L2CrossDomainMessenger', () => {
         'xDomainMsgSender',
         '0x0000000000000000000000000000000000000000'
       )
+
       expect(
         await Mock__L2CrossDomainMessenger.xDomainMessageSender()
       ).to.equal('0x0000000000000000000000000000000000000000')
@@ -94,49 +70,53 @@ describe('L2CrossDomainMessenger', () => {
   })
 
   describe('sendMessage', () => {
-    const target = NON_ZERO_ADDRESS
-    const message = NON_NULL_BYTES32
-    const gasLimit = 100_000
-
     it('should be able to send a single message', async () => {
       await expect(
-        L2CrossDomainMessenger.sendMessage(target, message, gasLimit)
+        L2CrossDomainMessenger.sendMessage(
+          NON_ZERO_ADDRESS,
+          NON_NULL_BYTES32,
+          100_000
+        )
       ).to.not.be.reverted
 
       expect(
         Fake__OVM_L2ToL1MessagePasser.passMessageToL1.getCall(0).args[0]
       ).to.deep.equal(
-        encodeXDomainCalldata(target, await signer.getAddress(), message, 0)
+        encodeXDomainCalldata(
+          NON_ZERO_ADDRESS,
+          await signer.getAddress(),
+          NON_NULL_BYTES32,
+          0
+        )
       )
     })
 
     it('should be able to send the same message twice', async () => {
-      await L2CrossDomainMessenger.sendMessage(target, message, gasLimit)
+      await L2CrossDomainMessenger.sendMessage(
+        NON_ZERO_ADDRESS,
+        NON_NULL_BYTES32,
+        100_000
+      )
 
       await expect(
-        L2CrossDomainMessenger.sendMessage(target, message, gasLimit)
+        L2CrossDomainMessenger.sendMessage(
+          NON_ZERO_ADDRESS,
+          NON_NULL_BYTES32,
+          100_000
+        )
       ).to.not.be.reverted
     })
   })
 
   describe('relayMessage', () => {
-    let target: string
-    let message: string
-    let sender: string
-    before(async () => {
-      target = Fake__TargetContract.address
-      message = Fake__TargetContract.interface.encodeFunctionData('setTarget', [
-        NON_ZERO_ADDRESS,
-      ])
-      sender = await signer.getAddress()
-    })
-
     it('should revert if the L1 message sender is not the L1CrossDomainMessenger', async () => {
       await expect(
         L2CrossDomainMessenger.connect(signer).relayMessage(
-          target,
-          sender,
-          message,
+          Fake__TargetContract.address,
+          signer.address,
+          Fake__TargetContract.interface.encodeFunctionData('setTarget', [
+            NON_ZERO_ADDRESS,
+          ]),
           0
         )
       ).to.be.revertedWith('Provided message could not be verified.')
@@ -145,7 +125,14 @@ describe('L2CrossDomainMessenger', () => {
     it('should send a call to the target contract', async () => {
       await L2CrossDomainMessenger.connect(
         impersonatedL1CrossDomainMessengerSender
-      ).relayMessage(target, sender, message, 0)
+      ).relayMessage(
+        Fake__TargetContract.address,
+        signer.address,
+        Fake__TargetContract.interface.encodeFunctionData('setTarget', [
+          NON_ZERO_ADDRESS,
+        ]),
+        0
+      )
 
       expect(Fake__TargetContract.setTarget.getCall(0).args[0]).to.deep.equal(
         NON_ZERO_ADDRESS
@@ -159,7 +146,14 @@ describe('L2CrossDomainMessenger', () => {
 
       await L2CrossDomainMessenger.connect(
         impersonatedL1CrossDomainMessengerSender
-      ).relayMessage(target, sender, message, 0)
+      ).relayMessage(
+        Fake__TargetContract.address,
+        signer.address,
+        Fake__TargetContract.interface.encodeFunctionData('setTarget', [
+          NON_ZERO_ADDRESS,
+        ]),
+        0
+      )
 
       await expect(
         L2CrossDomainMessenger.xDomainMessageSender()
@@ -169,45 +163,72 @@ describe('L2CrossDomainMessenger', () => {
     it('should revert if trying to send the same message twice', async () => {
       await L2CrossDomainMessenger.connect(
         impersonatedL1CrossDomainMessengerSender
-      ).relayMessage(target, sender, message, 0)
+      ).relayMessage(
+        Fake__TargetContract.address,
+        signer.address,
+        Fake__TargetContract.interface.encodeFunctionData('setTarget', [
+          NON_ZERO_ADDRESS,
+        ]),
+        0
+      )
 
       await expect(
         L2CrossDomainMessenger.connect(
           impersonatedL1CrossDomainMessengerSender
-        ).relayMessage(target, sender, message, 0)
+        ).relayMessage(
+          Fake__TargetContract.address,
+          signer.address,
+          Fake__TargetContract.interface.encodeFunctionData('setTarget', [
+            NON_ZERO_ADDRESS,
+          ]),
+          0
+        )
       ).to.be.revertedWith('Provided message has already been received.')
     })
 
     it('should not make a call if the target is the L2 MessagePasser', async () => {
-      target = predeploys.OVM_L2ToL1MessagePasser
-      message = Fake__OVM_L2ToL1MessagePasser.interface.encodeFunctionData(
-        'passMessageToL1(bytes)',
-        [NON_NULL_BYTES32]
-      )
-
       const resProm = L2CrossDomainMessenger.connect(
         impersonatedL1CrossDomainMessengerSender
-      ).relayMessage(target, sender, message, 0)
+      ).relayMessage(
+        predeploys.OVM_L2ToL1MessagePasser,
+        signer.address,
+        Fake__OVM_L2ToL1MessagePasser.interface.encodeFunctionData(
+          'passMessageToL1(bytes)',
+          [NON_NULL_BYTES32]
+        ),
+        0
+      )
 
       // The call to relayMessage() should succeed.
       await expect(resProm).to.not.be.reverted
 
       // There should be no 'relayedMessage' event logged in the receipt.
-      const logs = (
-        await Fake__OVM_L2ToL1MessagePasser.provider.getTransactionReceipt(
-          (
-            await resProm
-          ).hash
-        )
-      ).logs
-      expect(logs).to.deep.equal([])
+      expect(
+        (
+          await Fake__OVM_L2ToL1MessagePasser.provider.getTransactionReceipt(
+            (
+              await resProm
+            ).hash
+          )
+        ).logs
+      ).to.deep.equal([])
 
       // The message should be registered as successful.
       expect(
         await L2CrossDomainMessenger.successfulMessages(
           ethers.utils.solidityKeccak256(
             ['bytes'],
-            [encodeXDomainCalldata(target, sender, message, 0)]
+            [
+              encodeXDomainCalldata(
+                predeploys.OVM_L2ToL1MessagePasser,
+                signer.address,
+                Fake__OVM_L2ToL1MessagePasser.interface.encodeFunctionData(
+                  'passMessageToL1(bytes)',
+                  [NON_NULL_BYTES32]
+                ),
+                0
+              ),
+            ]
           )
         )
       ).to.be.true

packages/contracts/test/helpers/utils/impersonation.ts

+import { toRpcHexString } from '@eth-optimism/core-utils'
+import { SignerWithAddress } from '@nomiclabs/hardhat-ethers/signers'
+import { BigNumber } from 'ethers'
+import hre from 'hardhat'
+
+export const impersonate = async (
+  address: string,
+  balance?: string | number | BigNumber
+): Promise<SignerWithAddress> => {
+  await hre.network.provider.request({
+    method: 'hardhat_impersonateAccount',
+    params: [address],
+  })
+
+  if (balance !== undefined) {
+    await hre.network.provider.request({
+      method: 'hardhat_setBalance',
+      params: [address, toRpcHexString(BigNumber.from(balance))],
+    })
+  }
+
+  return hre.ethers.getSigner(address)
+}

packages/contracts/test/helpers/utils/index.ts

 export * from './eth-time'
 export * from './deploy'
+export * from './impersonation'