Add basic test scaffolding

contracts/l2/L2DAIWormholeBridge.sol

@@ -28,7 +28,7 @@ interface Mintable {
   function burn(address usr, uint256 wad) external;
 }
 
-contract L2DAIWormholeTokenBridge is OVM_CrossDomainEnabled {
+contract L2DAIWormholeBridge is OVM_CrossDomainEnabled {
   using WormholeLib for WormholeGUID;
 
   // --- Auth ---

test/l2/L2DAIWormholeBridge.ts

@@ -0,0 +1,50 @@
+import { simpleDeploy } from '@makerdao/hardhat-utils'
+import { SignerWithAddress } from '@nomiclabs/hardhat-ethers/dist/src/signer-with-address'
+import { expect } from 'chai'
+import { ethers } from 'hardhat'
+
+import { Dai__factory, L2DAIWormholeBridge__factory } from '../../typechain'
+import { deployMock, deployOptimismContractMock } from '../helpers'
+
+const INITIAL_TOTAL_L2_SUPPLY = 3000
+const WORMHOLE_AMOUNT = 100
+const SOURCE_DOMAIN_NAME = ethers.utils.formatBytes32String('optimism-a')
+const TARGET_DOMAIN_NAME = ethers.utils.formatBytes32String('arbitrum-a')
+
+describe('L2DAIWormholeBridge', () => {
+  describe('initiateWormhole()', () => {
+    it('should burn DAI immediately and mark it for future flush', async () => {
+      const [_, l2MessengerImpersonator, user1] = await ethers.getSigners()
+      const { l2Dai, l2DAIWormholeBridge } = await setupTest({ l2MessengerImpersonator, user1 })
+
+      await l2DAIWormholeBridge
+        .connect(user1)
+        .initiateWormhole(TARGET_DOMAIN_NAME, user1.address, WORMHOLE_AMOUNT, user1.address)
+
+      expect(await l2Dai.balanceOf(user1.address)).to.eq(INITIAL_TOTAL_L2_SUPPLY - WORMHOLE_AMOUNT)
+      expect(await l2DAIWormholeBridge.batchedDaiToFlush(TARGET_DOMAIN_NAME)).to.eq(WORMHOLE_AMOUNT)
+    })
+  })
+})
+
+async function setupTest(signers: { l2MessengerImpersonator: SignerWithAddress; user1: SignerWithAddress }) {
+  const l2CrossDomainMessengerMock = await deployOptimismContractMock(
+    'OVM_L2CrossDomainMessenger',
+    { address: await signers.l2MessengerImpersonator.getAddress() }, // This allows us to use an ethers override {from: Mock__OVM_L2CrossDomainMessenger.address} to mock calls
+  )
+  const l1Dai = await simpleDeploy<Dai__factory>('Dai', [])
+  const l2Dai = await simpleDeploy<Dai__factory>('Dai', [])
+  const l1DAIWormholeBridgeMock = await deployMock('L1DAIWormholeBridge')
+  const l2DAIWormholeBridge = await simpleDeploy<L2DAIWormholeBridge__factory>('L2DAIWormholeBridge', [
+    l2CrossDomainMessengerMock.address,
+    l2Dai.address,
+    l1Dai.address,
+    l1DAIWormholeBridgeMock.address,
+    SOURCE_DOMAIN_NAME,
+  ])
+
+  await l2Dai.rely(l2DAIWormholeBridge.address)
+  await l2Dai.mint(signers.user1.address, INITIAL_TOTAL_L2_SUPPLY)
+
+  return { l2Dai, l1DAIWormholeBridgeMock, l2CrossDomainMessengerMock, l2DAIWormholeBridge, l1Dai }
+}