feat: add sdk utils and corresponding tests

.changeset/clever-bananas-look.md

+---
+'@eth-optimism/contracts': patch
+---
+
+Adds a new TestLib_CrossDomainUtils so we can properly test cross chain encoding functions

ops/docker/Dockerfile.monorepo

@@ -24,6 +24,7 @@ FROM node as builder
 WORKDIR /optimism
 COPY .git ./.git
 COPY *.json yarn.lock ./
+COPY packages/sdk/package.json ./packages/sdk/package.json
 COPY packages/core-utils/package.json ./packages/core-utils/package.json
 COPY packages/common-ts/package.json ./packages/common-ts/package.json
 COPY packages/contracts/package.json ./packages/contracts/package.json

packages/contracts/contracts/test-libraries/bridge/TestLib_CrossDomainUtils.sol

+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.9;
+
+/* Library Imports */
+import { Lib_CrossDomainUtils } from "../../libraries/bridge/Lib_CrossDomainUtils.sol";
+
+/**
+ * @title TestLib_CrossDomainUtils
+ */
+library TestLib_CrossDomainUtils {
+    function encodeXDomainCalldata(
+        address _target,
+        address _sender,
+        bytes memory _message,
+        uint256 _messageNonce
+    ) public pure returns (bytes memory) {
+        return
+            Lib_CrossDomainUtils.encodeXDomainCalldata(_target, _sender, _message, _messageNonce);
+    }
+}

packages/sdk/hardhat.config.ts

+import { HardhatUserConfig } from 'hardhat/types'
+
+import '@nomiclabs/hardhat-ethers'
+import '@nomiclabs/hardhat-waffle'
+
+const config: HardhatUserConfig = {
+  solidity: {
+    version: '0.8.9',
+  },
+  paths: {
+    sources: './test/contracts',
+  },
+}
+
+export default config

packages/sdk/package.json

@@ -14,7 +14,9 @@
     "lint": "yarn lint:fix && yarn lint:check",
     "lint:check": "eslint .",
     "lint:fix": "yarn lint:check --fix",
-    "pre-commit": "lint-staged"
+    "pre-commit": "lint-staged",
+    "test": "hardhat test",
+    "test:coverage": "nyc hardhat test && nyc merge .nyc_output coverage.json"
   },
   "keywords": [
     "optimism",

packages/sdk/src/index.ts

 export * from './interfaces'
+export * from './utils'

packages/sdk/src/interfaces/types.ts

@@ -106,6 +106,14 @@ export interface CrossChainMessage {
   messageNonce: number
 }
 
+/**
+ * Convenience type for when you don't care which direction the message is going in.
+ */
+export type DirectionlessCrossChainMessage = Omit<
+  CrossChainMessage,
+  'direction'
+>
+
 /**
  * Describes a token withdrawal or deposit, along with the underlying raw cross chain message
  * behind the deposit or withdrawal.
@@ -188,7 +196,7 @@ export type MessageLike =
 /**
  * Stuff that can be coerced into a provider.
  */
-export type ProviderLike = string | Provider
+export type ProviderLike = string | Provider | any
 
 /**
  * Stuff that can be coerced into a signer.

packages/sdk/src/utils.ts

+import assert from 'assert'
+import {
+  Provider,
+  TransactionReceipt,
+  TransactionResponse,
+} from '@ethersproject/abstract-provider'
+import { getContractInterface } from '@eth-optimism/contracts'
+import { ethers } from 'ethers'
+import {
+  ProviderLike,
+  TransactionLike,
+  DirectionlessCrossChainMessage,
+} from './interfaces'
+
+/**
+ * Returns the canonical encoding of a cross chain message. This encoding is used in various
+ * locations within the Optimistic Ethereum smart contracts.
+ *
+ * @param message Cross chain message to encode.
+ * @returns Canonical encoding of the message.
+ */
+export const encodeCrossChainMessage = (
+  message: DirectionlessCrossChainMessage
+): string => {
+  return getContractInterface('L2CrossDomainMessenger').encodeFunctionData(
+    'relayMessage',
+    [message.target, message.sender, message.message, message.messageNonce]
+  )
+}
+
+/**
+ * Returns the canonical hash of a cross chain message. This hash is used in various locations
+ * within the Optimistic Ethereum smart contracts and is the keccak256 hash of the result of
+ * encodeCrossChainMessage.
+ *
+ * @param message Cross chain message to hash.
+ * @returns Canonical hash of the message.
+ */
+export const hashCrossChainMessage = (
+  message: DirectionlessCrossChainMessage
+): string => {
+  return ethers.utils.solidityKeccak256(
+    ['bytes'],
+    [encodeCrossChainMessage(message)]
+  )
+}
+
+/**
+ * Converts a ProviderLike into a provider. Assumes that if the ProviderLike is a string then
+ * it is a JSON-RPC url.
+ *
+ * @param provider ProviderLike to turn into a provider.
+ * @returns ProviderLike as a provider.
+ */
+export const toProvider = (provider: ProviderLike): Provider => {
+  if (typeof provider === 'string') {
+    return new ethers.providers.JsonRpcProvider(provider)
+  } else if (Provider.isProvider(provider)) {
+    return provider
+  } else {
+    throw new Error('Invalid provider')
+  }
+}
+
+/**
+ * Pulls a transaction hash out of a TransactionLike object.
+ *
+ * @param transaction TransactionLike to convert into a transaction hash.
+ * @returns Transaction hash corresponding to the TransactionLike input.
+ */
+export const toTransactionHash = (transaction: TransactionLike): string => {
+  if (typeof transaction === 'string') {
+    assert(
+      ethers.utils.isHexString(transaction, 32),
+      'Invalid transaction hash'
+    )
+
+    return transaction
+  } else if ((transaction as TransactionReceipt).transactionHash) {
+    return (transaction as TransactionReceipt).transactionHash
+  } else if ((transaction as TransactionResponse).hash) {
+    return (transaction as TransactionResponse).hash
+  } else {
+    throw new Error('Invalid transaction')
+  }
+}

packages/sdk/test/contracts/AbsolutelyNothing.sol

+pragma solidity ^0.8.9;
+
+contract AbsolutelyNothing {
+    function doAbsolutelyNothing() public {
+        return;
+    }
+}

packages/sdk/test/contracts/MessageEncodingHelper.sol

+pragma solidity ^0.8.9;
+
+contract MessageEncodingHelper {
+    // This function is copy/pasted from the Lib_CrossDomainUtils library. We have to do this
+    // because the Lib_CrossDomainUtils library does not provide a function for hashing. Instead,
+    // I'm duplicating the functionality of the library here and exposing an additional method that
+    // does the required hashing. This is fragile and will break if we ever update the way that our
+    // contracts hash the encoded data, but at least it works for now.
+    // TODO: Next time we're planning to upgrade the contracts, make sure that the library also
+    // contains a function for hashing.
+    function encodeXDomainCalldata(
+        address _target,
+        address _sender,
+        bytes memory _message,
+        uint256 _messageNonce
+    ) public pure returns (bytes memory) {
+        return
+            abi.encodeWithSignature(
+                "relayMessage(address,address,bytes,uint256)",
+                _target,
+                _sender,
+                _message,
+                _messageNonce
+            );
+    }
+
+    function hashXDomainCalldata(
+        address _target,
+        address _sender,
+        bytes memory _message,
+        uint256 _messageNonce
+    ) public pure returns (bytes32) {
+        return keccak256(
+            encodeXDomainCalldata(
+                _target,
+                _sender,
+                _message,
+                _messageNonce
+            )
+        );
+    }
+}

packages/sdk/test/utils.spec.ts

+import { expect } from './setup'
+import { Provider } from '@ethersproject/abstract-provider'
+import { Contract, Signer } from 'ethers'
+import { ethers } from 'hardhat'
+import { getContractFactory } from '@eth-optimism/contracts'
+import {
+  toProvider,
+  toTransactionHash,
+  CrossChainMessage,
+  MessageDirection,
+  encodeCrossChainMessage,
+  hashCrossChainMessage,
+} from '../src'
+
+describe('utils', () => {
+  let signers: Signer[]
+  before(async () => {
+    signers = (await ethers.getSigners()) as any
+  })
+
+  describe('encodeCrossChainMessage', () => {
+    let Lib_CrossDomainUtils: Contract
+    before(async () => {
+      Lib_CrossDomainUtils = (await getContractFactory(
+        'TestLib_CrossDomainUtils',
+        signers[0]
+      ).deploy()) as any
+    })
+
+    it('should properly encode a message', async () => {
+      const message: CrossChainMessage = {
+        direction: MessageDirection.L1_TO_L2,
+        target: '0x' + '11'.repeat(20),
+        sender: '0x' + '22'.repeat(20),
+        message: '0x' + '1234'.repeat(32),
+        messageNonce: 1234,
+      }
+
+      const actual = encodeCrossChainMessage(message)
+      const expected = await Lib_CrossDomainUtils.encodeXDomainCalldata(
+        message.target,
+        message.sender,
+        message.message,
+        message.messageNonce
+      )
+      expect(actual).to.equal(expected)
+    })
+  })
+
+  describe('hashCrossChainMessage', () => {
+    let MessageEncodingHelper: Contract
+    before(async () => {
+      MessageEncodingHelper = (await (
+        await ethers.getContractFactory('MessageEncodingHelper')
+      ).deploy()) as any
+    })
+
+    it('should properly hash a message', async () => {
+      const message: CrossChainMessage = {
+        direction: MessageDirection.L1_TO_L2,
+        target: '0x' + '11'.repeat(20),
+        sender: '0x' + '22'.repeat(20),
+        message: '0x' + '1234'.repeat(32),
+        messageNonce: 1234,
+      }
+
+      const actual = hashCrossChainMessage(message)
+      const expected = await MessageEncodingHelper.hashXDomainCalldata(
+        message.target,
+        message.sender,
+        message.message,
+        message.messageNonce
+      )
+      expect(actual).to.equal(expected)
+    })
+  })
+
+  describe('toProvider', () => {
+    it('should convert a string to a JsonRpcProvider', () => {
+      const provider = toProvider('http://localhost:8545')
+      expect(Provider.isProvider(provider)).to.be.true
+    })
+
+    it('should not do anything with a provider', () => {
+      const provider = toProvider(ethers.provider)
+      expect(provider).to.deep.equal(ethers.provider)
+    })
+  })
+
+  describe('toTransactionHash', () => {
+    describe('string inputs', () => {
+      it('should return the input if the input is a valid transaction hash', () => {
+        const input = '0x' + '11'.repeat(32)
+        expect(toTransactionHash(input)).to.equal(input)
+      })
+
+      it('should throw an error if the input is a hex string but not a transaction hash', () => {
+        const input = '0x' + '11'.repeat(31)
+        expect(() => toTransactionHash(input)).to.throw(
+          'Invalid transaction hash'
+        )
+      })
+
+      it('should throw an error if the input is not a hex string', () => {
+        const input = 'hi mom look at me go'
+        expect(() => toTransactionHash(input)).to.throw(
+          'Invalid transaction hash'
+        )
+      })
+    })
+
+    describe('transaction inputs', () => {
+      let AbsolutelyNothing: Contract
+      before(async () => {
+        AbsolutelyNothing = (await (
+          await ethers.getContractFactory('AbsolutelyNothing')
+        ).deploy()) as any
+      })
+
+      it('should return the transaction hash if the input is a transaction response', async () => {
+        const tx = await AbsolutelyNothing.doAbsolutelyNothing()
+        expect(toTransactionHash(tx)).to.equal(tx.hash)
+      })
+
+      it('should return the transaction hash if the input is a transaction receipt', async () => {
+        const tx = await AbsolutelyNothing.doAbsolutelyNothing()
+        const receipt = await tx.wait()
+        expect(toTransactionHash(receipt)).to.equal(receipt.transactionHash)
+      })
+    })
+
+    describe('other types', () => {
+      it('should throw if given a number as an input', () => {
+        expect(() => toTransactionHash(1234 as any)).to.throw(
+          'Invalid transaction'
+        )
+      })
+
+      it('should throw if given a function as an input', () => {
+        expect(() =>
+          toTransactionHash((() => {
+            return 1234
+          }) as any)
+        ).to.throw('Invalid transaction')
+      })
+    })
+  })
+})