sdk: bugfixes

.circleci/config.yml

@@ -5,7 +5,7 @@ orbs:
   gcp-cli: circleci/gcp-cli@3.0.1
 commands:
   gcp-oidc-authenticate:
-    description: "Authenticate with GCP using a CircleCI OIDC token."
+    description: 'Authenticate with GCP using a CircleCI OIDC token.'
     parameters:
       project_id:
         type: env_var_name
@@ -27,7 +27,7 @@ commands:
         default: /home/circleci/oidc_token.json
     steps:
       - run:
-          name: "Create OIDC credential configuration"
+          name: 'Create OIDC credential configuration'
           command: |
             # Store OIDC token in temp file
             echo $CIRCLE_OIDC_TOKEN > << parameters.oidc_token_file_path >>
@@ -38,21 +38,21 @@ commands:
                 --service-account="${<< parameters.service_account_email >>}" \
                 --credential-source-file=<< parameters.oidc_token_file_path >>
       - run:
-          name: "Authenticate with GCP using OIDC"
+          name: 'Authenticate with GCP using OIDC'
           command: |
             # Configure gcloud to leverage the generated credential configuration
             gcloud auth login --brief --cred-file "<< parameters.gcp_cred_config_file_path >>"
             # Configure ADC
             echo "export GOOGLE_APPLICATION_CREDENTIALS='<< parameters.gcp_cred_config_file_path >>'" | tee -a "$BASH_ENV"
   check-changed:
-    description: "Conditionally halts a step if certain modules change"
+    description: 'Conditionally halts a step if certain modules change'
     parameters:
       patterns:
         type: string
-        description: "Comma-separated list of dependencies"
+        description: 'Comma-separated list of dependencies'
     steps:
       - run:
-          name: "Check for changes"
+          name: 'Check for changes'
           command: |
             cd ops/check-changed
             pip3 install -r requirements.txt
@@ -77,26 +77,26 @@ jobs:
           name: Save Yarn Package Cache
           key: yarn-packages-v2-{{ checksum "yarn.lock" }}
           paths:
-            - "node_modules"
-            - "packages/actor-tests/node_modules"
-            - "packages/atst/node_modules"
-            - "packages/balance-monitor/node_modules"
-            - "packages/chain-mon/node_modules"
-            - "packages/common-ts/node_modules"
-            - "packages/contracts/node_modules"
-            - "packages/contracts-bedrock/node_modules"
-            - "packages/contracts-governance/node_modules"
-            - "packages/contracts-periphery/node_modules"
-            - "packages/core-utils/node_modules"
-            - "packages/data-transport-layer/node_modules"
-            - "packages/drippie-mon/node_modules"
-            - "packages/fault-detector/node_modules"
-            - "packages/hardhat-deploy-config/node_modules"
-            - "packages/integration-tests-bedrock/node_modules"
-            - "packages/message-relayer/node_modules"
-            - "packages/migration-data/node_modules"
-            - "packages/replica-healthcheck/node_modules"
-            - "packages/sdk/node_modules"
+            - 'node_modules'
+            - 'packages/actor-tests/node_modules'
+            - 'packages/atst/node_modules'
+            - 'packages/balance-monitor/node_modules'
+            - 'packages/chain-mon/node_modules'
+            - 'packages/common-ts/node_modules'
+            - 'packages/contracts/node_modules'
+            - 'packages/contracts-bedrock/node_modules'
+            - 'packages/contracts-governance/node_modules'
+            - 'packages/contracts-periphery/node_modules'
+            - 'packages/core-utils/node_modules'
+            - 'packages/data-transport-layer/node_modules'
+            - 'packages/drippie-mon/node_modules'
+            - 'packages/fault-detector/node_modules'
+            - 'packages/hardhat-deploy-config/node_modules'
+            - 'packages/integration-tests-bedrock/node_modules'
+            - 'packages/message-relayer/node_modules'
+            - 'packages/migration-data/node_modules'
+            - 'packages/replica-healthcheck/node_modules'
+            - 'packages/sdk/node_modules'
       - run:
           name: print forge version
           command: forge --version
@@ -104,17 +104,17 @@ jobs:
           name: Build monorepo
           command: yarn build
       - persist_to_workspace:
-          root: "."
+          root: '.'
           paths:
-            - "packages/*/dist"
-            - "packages/*/artifacts"
-            - "packages/contracts/src/contract-artifacts.ts"
-            - "packages/contracts/src/contract-deployed-artifacts.ts"
-            - "packages/contracts/chugsplash"
-            - "packages/contracts/L1"
-            - "packages/contracts/L2"
-            - "packages/contracts/libraries"
-            - "packages/contracts/standards"
+            - 'packages/*/dist'
+            - 'packages/*/artifacts'
+            - 'packages/contracts/src/contract-artifacts.ts'
+            - 'packages/contracts/src/contract-deployed-artifacts.ts'
+            - 'packages/contracts/chugsplash'
+            - 'packages/contracts/L1'
+            - 'packages/contracts/L2'
+            - 'packages/contracts/libraries'
+            - 'packages/contracts/standards'
 
   docker-build:
     environment:
@@ -135,11 +135,11 @@ jobs:
       registry:
         description: Docker registry
         type: string
-        default: "us-docker.pkg.dev"
+        default: 'us-docker.pkg.dev'
       repo:
         description: Docker repo
         type: string
-        default: "oplabs-tools-artifacts/images"
+        default: 'oplabs-tools-artifacts/images'
     machine:
       image: ubuntu-2204:2022.07.1
       resource_class: medium
@@ -170,7 +170,7 @@ jobs:
       - persist_to_workspace:
           root: /tmp/docker_images
           paths:
-            - "."
+            - '.'
 
   docker-publish:
     environment:
@@ -188,23 +188,23 @@ jobs:
       docker_context:
         description: Docker build context
         type: string
-        default: "."
+        default: '.'
       docker_target:
-        description: "target build stage"
+        description: 'target build stage'
         type: string
-        default: ""
+        default: ''
       registry:
         description: Docker registry
         type: string
-        default: "us-docker.pkg.dev"
+        default: 'us-docker.pkg.dev'
       repo:
         description: Docker repo
         type: string
-        default: "oplabs-tools-artifacts/images"
+        default: 'oplabs-tools-artifacts/images'
       platforms:
         description: Platforms to build for
         type: string
-        default: "linux/amd64"
+        default: 'linux/amd64'
     machine:
       image: ubuntu-2204:2022.07.1
       resource_class: medium
@@ -250,15 +250,15 @@ jobs:
       registry:
         description: Docker registry
         type: string
-        default: "us-docker.pkg.dev"
+        default: 'us-docker.pkg.dev'
       repo:
         description: Docker repo
         type: string
-        default: "oplabs-tools-artifacts/images"
+        default: 'oplabs-tools-artifacts/images'
       platforms:
         description: Platforms to build for
         type: string
-        default: "linux/amd64"
+        default: 'linux/amd64'
     machine:
       image: ubuntu-2204:2022.07.1
       resource_class: medium
@@ -321,7 +321,7 @@ jobs:
     resource_class: large
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -344,7 +344,7 @@ jobs:
       - image: us-docker.pkg.dev/oplabs-tools-artifacts/images/ci-builder:latest
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -405,7 +405,7 @@ jobs:
     resource_class: large
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -424,7 +424,7 @@ jobs:
       - image: us-docker.pkg.dev/oplabs-tools-artifacts/images/ci-builder:latest
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -441,7 +441,7 @@ jobs:
       - image: us-docker.pkg.dev/oplabs-tools-artifacts/images/ci-builder:latest
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - check-changed:
           patterns: contracts-bedrock,contracts
       - run:
@@ -451,7 +451,7 @@ jobs:
       - persist_to_workspace:
           root: .
           paths:
-            - "node_modules"
+            - 'node_modules'
             - packages/contracts-bedrock
 
   bedrock-echidna-run:
@@ -468,7 +468,7 @@ jobs:
     resource_class: <<parameters.size>>
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -487,7 +487,7 @@ jobs:
     resource_class: medium
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -516,7 +516,7 @@ jobs:
     resource_class: large
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -544,6 +544,10 @@ jobs:
       - attach_workspace: { at: '.' }
       - check-changed:
           patterns: sdk,contracts-bedrock,contracts
+      - restore_cache:
+          name: Restore Yarn Package Cache
+          keys:
+            - yarn-packages-v2-{{ checksum "yarn.lock" }}
       - run:
           name: anvil-l1
           background: true
@@ -552,6 +556,14 @@ jobs:
           name: anvil-l2
           background: true
           command: anvil --fork-url $ANVIL_L2_FORK_URL --port 9545
+      - run:
+          name: build
+          command: yarn build
+          working_directory: packages/atst
+      - run:
+          name: lint
+          command: yarn lint:check
+          working_directory: packages/atst
       - run:
           name: make sure anvil l1 is up
           command: cast block-number --rpc-url http://localhost:8545
@@ -565,9 +577,9 @@ jobs:
           working_directory: packages/sdk
           environment:
             # anvil[0] test private key
-            VITE_E2E_PRIVATE_KEY: 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
-            VITE_E2E_RPC_URLS_L1: http://localhost:8545
-            VITE_E2E_RPC_URLS_L2: http://localhost:9545
+            VITE_E2E_PRIVATE_KEY: '0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80'
+            VITE_E2E_RPC_URL_L1: http://localhost:8545
+            VITE_E2E_RPC_URL_L2: http://localhost:9545
 
   bedrock-markdown:
     machine:
@@ -577,7 +589,7 @@ jobs:
       - check-changed:
           patterns: specs/(.*)\.md$
       - run:
-          name: yarn dev deps  # todo: what's the best way to pull in the dependencies for linting? yarn install above is using production env without dev dependencies
+          name: yarn dev deps # todo: what's the best way to pull in the dependencies for linting? yarn install above is using production env without dev dependencies
           command: yarn install --production=false
       - run:
           name: specs toc
@@ -607,7 +619,7 @@ jobs:
       - image: us-docker.pkg.dev/oplabs-tools-artifacts/images/ci-builder:latest
     steps:
       - checkout
-      - attach_workspace: { at: "." }
+      - attach_workspace: { at: '.' }
       - restore_cache:
           name: Restore Yarn Package Cache
           keys:
@@ -753,7 +765,7 @@ jobs:
           working_directory: <<parameters.working_directory>>
       - when:
           condition:
-            equal: [ true, <<parameters.build>> ]
+            equal: [true, <<parameters.build>>]
           steps:
             - run:
                 name: Build
@@ -809,7 +821,7 @@ jobs:
       - when:
           condition:
             and:
-              - equal: [ true, <<parameters.deploy>> ]
+              - equal: [true, <<parameters.deploy>>]
           steps:
             - run:
                 name: Bring up the stack
@@ -859,7 +871,7 @@ jobs:
       - when:
           condition:
             and:
-              - equal: [ false, <<parameters.deploy>> ]
+              - equal: [false, <<parameters.deploy>>]
           steps:
             - run:
                 name: Bring up the stack
@@ -962,22 +974,22 @@ jobs:
       - checkout
       - unless:
           condition:
-            equal: [ "develop", << pipeline.git.branch >> ]
+            equal: ['develop', << pipeline.git.branch >>]
           steps:
             - run:
                 # Scan changed files in PRs, block on new issues only (existing issues ignored)
                 # Do a full scan when scanning develop, otherwise do an incremental scan.
-                name: "Conditionally set BASELINE env var"
+                name: 'Conditionally set BASELINE env var'
                 command: |
                   echo 'export SEMGREP_BASELINE_REF=${TEMPORARY_BASELINE_REF}' >> $BASH_ENV
       - run:
-          name: "Set environment variables" # for PR comments and in-app hyperlinks to findings
+          name: 'Set environment variables' # for PR comments and in-app hyperlinks to findings
           command: |
             echo 'export SEMGREP_PR_ID=${CIRCLE_PULL_REQUEST##*/}' >> $BASH_ENV
             echo 'export SEMGREP_JOB_URL=$CIRCLE_BUILD_URL' >> $BASH_ENV
             echo 'export SEMGREP_REPO_NAME=$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME' >> $BASH_ENV
       - run:
-          name: "Semgrep scan"
+          name: 'Semgrep scan'
           command: semgrep ci
 
   go-mod-tidy:
@@ -986,7 +998,7 @@ jobs:
     steps:
       - checkout
       - run:
-          name: "Go mod tidy"
+          name: 'Go mod tidy'
           command: make mod-tidy && git diff --exit-code
 
   hive-test:
@@ -1014,7 +1026,7 @@ jobs:
       - go/load-cache
       - go/mod-download
       - go/save-cache
-      - run: { command: "go build ." }
+      - run: { command: 'go build .' }
       - run:
           command: |
             ./hive \
@@ -1024,7 +1036,7 @@ jobs:
       - run:
           command: |
             tar -cvf /tmp/workspace.tgz -C /home/circleci/project /home/circleci/project/workspace
-          name: "Archive workspace"
+          name: 'Archive workspace'
       - store_artifacts:
           path: /tmp/workspace.tgz
           destination: hive-workspace.tgz
@@ -1083,49 +1095,49 @@ workflows:
           name: actor-tests-tests
           coverage_flag: actor-tests-tests
           package_name: actor-tests
-          dependencies: "(core-utils|sdk)"
+          dependencies: '(core-utils|sdk)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: contracts-periphery-tests
           coverage_flag: contracts-periphery-tests
           package_name: contracts-periphery
-          dependencies: "(contracts|contracts-bedrock|core-utils|hardhat-deploy-config)"
+          dependencies: '(contracts|contracts-bedrock|core-utils|hardhat-deploy-config)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: dtl-tests
           coverage_flag: dtl-tests
           package_name: data-transport-layer
-          dependencies: "(common-ts|contracts|core-utils)"
+          dependencies: '(common-ts|contracts|core-utils)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: chain-mon-tests
           coverage_flag: chain-mon-tests
           package_name: chain-mon
-          dependencies: "(common-ts|contracts-periphery|core-utils|sdk)"
+          dependencies: '(common-ts|contracts-periphery|core-utils|sdk)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: fault-detector-tests
           coverage_flag: fault-detector-tests
           package_name: fault-detector
-          dependencies: "(common-ts|contracts|core-utils|sdk)"
+          dependencies: '(common-ts|contracts|core-utils|sdk)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: message-relayer-tests
           coverage_flag: message-relayer-tests
           package_name: message-relayer
-          dependencies: "(common-ts|core-utils|sdk)"
+          dependencies: '(common-ts|core-utils|sdk)'
           requires:
             - yarn-monorepo
       - js-lint-test:
           name: replica-healthcheck-tests
           coverage_flag: replica-healthcheck-tests
           package_name: replica-healthcheck
-          dependencies: "(common-ts|core-utils)"
+          dependencies: '(common-ts|core-utils)'
           requires:
             - yarn-monorepo
       - sdk-next-tests:
@@ -1136,7 +1148,7 @@ workflows:
           name: sdk-tests
           coverage_flag: sdk-tests
           package_name: sdk
-          dependencies: "(contracts|core-utils)"
+          dependencies: '(contracts|core-utils)'
           requires:
             - yarn-monorepo
       - js-lint-test:
@@ -1239,11 +1251,11 @@ workflows:
       - go-e2e-test:
           name: op-e2e-WS-tests
           module: op-e2e
-          use_http: "false"
+          use_http: 'false'
       - go-e2e-test:
           name: op-e2e-HTTP-tests
           module: op-e2e
-          use_http: "true"
+          use_http: 'true'
       - bedrock-go-tests:
           requires:
             - op-batcher-lint
@@ -1276,7 +1288,7 @@ workflows:
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           context:
             - oplabs-gcr
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
       - docker-build:
           name: op-batcher-docker-build
           docker_file: op-batcher/Dockerfile
@@ -1290,7 +1302,7 @@ workflows:
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           context:
             - oplabs-gcr
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
       - docker-build:
           name: op-proposer-docker-build
           docker_file: op-proposer/Dockerfile
@@ -1304,7 +1316,7 @@ workflows:
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           context:
             - oplabs-gcr
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
       - docker-build:
           name: op-heartbeat-docker-build
           docker_file: op-heartbeat/Dockerfile
@@ -1383,7 +1395,7 @@ workflows:
           docker_name: op-node
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           docker_context: .
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
           context:
             - oplabs-gcr-release
           requires:
@@ -1399,7 +1411,7 @@ workflows:
           docker_name: op-batcher
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           docker_context: .
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
           context:
             - oplabs-gcr-release
           requires:
@@ -1415,7 +1427,7 @@ workflows:
           docker_name: op-proposer
           docker_tags: <<pipeline.git.revision>>,<<pipeline.git.branch>>
           docker_context: .
-          platforms: "linux/amd64,linux/arm64"
+          platforms: 'linux/amd64,linux/arm64'
           context:
             - oplabs-gcr-release
           requires:

packages/sdk/src/cross-chain-messenger.ts

@@ -68,6 +68,7 @@ import {
   migratedWithdrawalGasLimit,
   DEPOSIT_CONFIRMATION_BLOCKS,
   CHAIN_BLOCK_TIMES,
+  hashMessageHash,
 } from './utils'
 
 export class CrossChainMessenger {
@@ -351,14 +352,12 @@ export class CrossChainMessenger {
       }
     }
 
-    const minGasLimit = migratedWithdrawalGasLimit(resolved.message)
-
     return {
       ...resolved,
       value,
-      minGasLimit,
+      minGasLimit: BigNumber.from(0),
       messageNonce: encodeVersionedNonce(
-        BigNumber.from(1),
+        BigNumber.from(0),
         resolved.messageNonce
       ),
     }
@@ -388,13 +387,23 @@ export class CrossChainMessenger {
       updated = resolved
     }
 
+    // Encode the updated message, we need this for legacy messages.
+    const encoded = encodeCrossDomainMessageV1(
+      updated.messageNonce,
+      updated.sender,
+      updated.target,
+      updated.value,
+      updated.minGasLimit,
+      updated.message
+    )
+
     // We need to figure out the final withdrawal data that was used to compute the withdrawal hash
     // inside the L2ToL1Message passer contract. Exact mechanism here depends on whether or not
     // this is a legacy message or a new Bedrock message.
     let gasLimit: BigNumber
     let messageNonce: BigNumber
     if (version.eq(0)) {
-      gasLimit = BigNumber.from(0)
+      gasLimit = migratedWithdrawalGasLimit(encoded)
       messageNonce = resolved.messageNonce
     } else {
       const receipt = await this.l2Provider.getTransactionReceipt(
@@ -433,14 +442,7 @@ export class CrossChainMessenger {
       target: this.contracts.l1.L1CrossDomainMessenger.address,
       value: updated.value,
       minGasLimit: gasLimit,
-      message: encodeCrossDomainMessageV1(
-        updated.messageNonce,
-        updated.sender,
-        updated.target,
-        updated.value,
-        updated.minGasLimit,
-        updated.message
-      ),
+      message: encoded,
     }
   }
 
@@ -1360,12 +1362,8 @@ export class CrossChainMessenger {
     }
 
     const withdrawal = await this.toLowLevelMessage(resolved)
-    const messageSlot = ethers.utils.keccak256(
-      ethers.utils.defaultAbiCoder.encode(
-        ['bytes32', 'uint256'],
-        [hashLowLevelMessage(withdrawal), ethers.constants.HashZero]
-      )
-    )
+    const hash = hashLowLevelMessage(withdrawal)
+    const messageSlot = hashMessageHash(hash)
 
     const stateTrieProof = await makeStateTrieProof(
       this.l2Provider as ethers.providers.JsonRpcProvider,
@@ -1465,9 +1463,8 @@ export class CrossChainMessenger {
       overrides?: Overrides
     }
   ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.proveMessage(message, opts)
-    )
+    const tx = await this.populateTransaction.proveMessage(message, opts)
+    return (opts?.signer || this.l1Signer).sendTransaction(tx)
   }
 
   /**
@@ -1771,7 +1768,8 @@ export class CrossChainMessenger {
 
       const withdrawal = await this.toLowLevelMessage(resolved)
       const proof = await this.getBedrockMessageProof(resolved)
-      return this.contracts.l1.OptimismPortal.populateTransaction.proveWithdrawalTransaction(
+
+      const args = [
         [
           withdrawal.messageNonce,
           withdrawal.sender,
@@ -1788,7 +1786,11 @@ export class CrossChainMessenger {
           proof.outputRootProof.latestBlockhash,
         ],
         proof.withdrawalProof,
-        opts?.overrides || {}
+        opts?.overrides || {},
+      ] as const
+
+      return this.contracts.l1.OptimismPortal.populateTransaction.proveWithdrawalTransaction(
+        ...args
       )
     },
 

packages/sdk/src/cross-chain-messenger.with-logs.ts

-/* eslint-disable @typescript-eslint/no-unused-vars */
-import {
-  Provider,
-  BlockTag,
-  TransactionReceipt,
-  TransactionResponse,
-  TransactionRequest,
-} from '@ethersproject/abstract-provider'
-import { Signer } from '@ethersproject/abstract-signer'
-import {
-  ethers,
-  BigNumber,
-  Overrides,
-  CallOverrides,
-  PayableOverrides,
-} from 'ethers'
-import {
-  sleep,
-  remove0x,
-  toHexString,
-  toRpcHexString,
-  hashCrossDomainMessage,
-  encodeCrossDomainMessageV0,
-  encodeCrossDomainMessageV1,
-  BedrockOutputData,
-  BedrockCrossChainMessageProof,
-  decodeVersionedNonce,
-  encodeVersionedNonce,
-} from '@eth-optimism/core-utils'
-import { getContractInterface, predeploys } from '@eth-optimism/contracts'
-import * as rlp from 'rlp'
-
-import {
-  OEContracts,
-  OEContractsLike,
-  MessageLike,
-  MessageRequestLike,
-  TransactionLike,
-  AddressLike,
-  NumberLike,
-  SignerOrProviderLike,
-  CrossChainMessage,
-  CrossChainMessageRequest,
-  CrossChainMessageProof,
-  MessageDirection,
-  MessageStatus,
-  TokenBridgeMessage,
-  MessageReceipt,
-  MessageReceiptStatus,
-  BridgeAdapterData,
-  BridgeAdapters,
-  StateRoot,
-  StateRootBatch,
-  IBridgeAdapter,
-  ProvenWithdrawal,
-  LowLevelMessage,
-} from './interfaces'
-import {
-  toSignerOrProvider,
-  toNumber,
-  toTransactionHash,
-  DeepPartial,
-  getAllOEContracts,
-  getBridgeAdapters,
-  makeMerkleTreeProof,
-  makeStateTrieProof,
-  hashLowLevelMessage,
-  migratedWithdrawalGasLimit,
-  DEPOSIT_CONFIRMATION_BLOCKS,
-  CHAIN_BLOCK_TIMES,
-} from './utils'
-
-export class CrossChainMessenger {
-  /**
-   * Provider connected to the L1 chain.
-   */
-  public l1SignerOrProvider: Signer | Provider
-
-  /**
-   * Provider connected to the L2 chain.
-   */
-  public l2SignerOrProvider: Signer | Provider
-
-  /**
-   * Chain ID for the L1 network.
-   */
-  public l1ChainId: number
-
-  /**
-   * Chain ID for the L2 network.
-   */
-  public l2ChainId: number
-
-  /**
-   * Contract objects attached to their respective providers and addresses.
-   */
-  public contracts: OEContracts
-
-  /**
-   * List of custom bridges for the given network.
-   */
-  public bridges: BridgeAdapters
-
-  /**
-   * Number of blocks before a deposit is considered confirmed.
-   */
-  public depositConfirmationBlocks: number
-
-  /**
-   * Estimated average L1 block time in seconds.
-   */
-  public l1BlockTimeSeconds: number
-
-  /**
-   * Whether or not Bedrock compatibility is enabled.
-   */
-  public bedrock: boolean
-
-  /**
-   * Creates a new CrossChainProvider instance.
-   *
-   * @param opts Options for the provider.
-   * @param opts.l1SignerOrProvider Signer or Provider for the L1 chain, or a JSON-RPC url.
-   * @param opts.l2SignerOrProvider Signer or Provider for the L2 chain, or a JSON-RPC url.
-   * @param opts.l1ChainId Chain ID for the L1 chain.
-   * @param opts.l2ChainId Chain ID for the L2 chain.
-   * @param opts.depositConfirmationBlocks Optional number of blocks before a deposit is confirmed.
-   * @param opts.l1BlockTimeSeconds Optional estimated block time in seconds for the L1 chain.
-   * @param opts.contracts Optional contract address overrides.
-   * @param opts.bridges Optional bridge address list.
-   * @param opts.bedrock Whether or not to enable Bedrock compatibility.
-   */
-  constructor(opts: {
-    l1SignerOrProvider: SignerOrProviderLike
-    l2SignerOrProvider: SignerOrProviderLike
-    l1ChainId: NumberLike
-    l2ChainId: NumberLike
-    depositConfirmationBlocks?: NumberLike
-    l1BlockTimeSeconds?: NumberLike
-    contracts?: DeepPartial<OEContractsLike>
-    bridges?: BridgeAdapterData
-    bedrock?: boolean
-  }) {
-    this.bedrock = opts.bedrock ?? false
-    this.l1SignerOrProvider = toSignerOrProvider(opts.l1SignerOrProvider)
-    this.l2SignerOrProvider = toSignerOrProvider(opts.l2SignerOrProvider)
-
-    try {
-      this.l1ChainId = toNumber(opts.l1ChainId)
-    } catch (err) {
-      throw new Error(`L1 chain ID is missing or invalid: ${opts.l1ChainId}`)
-    }
-
-    try {
-      this.l2ChainId = toNumber(opts.l2ChainId)
-    } catch (err) {
-      throw new Error(`L2 chain ID is missing or invalid: ${opts.l2ChainId}`)
-    }
-
-    this.depositConfirmationBlocks =
-      opts?.depositConfirmationBlocks !== undefined
-        ? toNumber(opts.depositConfirmationBlocks)
-        : DEPOSIT_CONFIRMATION_BLOCKS[this.l2ChainId] || 0
-
-    this.l1BlockTimeSeconds =
-      opts?.l1BlockTimeSeconds !== undefined
-        ? toNumber(opts.l1BlockTimeSeconds)
-        : CHAIN_BLOCK_TIMES[this.l1ChainId] || 1
-
-    this.contracts = getAllOEContracts(this.l2ChainId, {
-      l1SignerOrProvider: this.l1SignerOrProvider,
-      l2SignerOrProvider: this.l2SignerOrProvider,
-      overrides: opts.contracts,
-    })
-
-    this.bridges = getBridgeAdapters(this.l2ChainId, this, {
-      overrides: opts.bridges,
-      contracts: opts.contracts,
-    })
-  }
-
-  /**
-   * Provider connected to the L1 chain.
-   */
-  get l1Provider(): Provider {
-    if (Provider.isProvider(this.l1SignerOrProvider)) {
-      return this.l1SignerOrProvider
-    } else {
-      return this.l1SignerOrProvider.provider
-    }
-  }
-
-  /**
-   * Provider connected to the L2 chain.
-   */
-  get l2Provider(): Provider {
-    if (Provider.isProvider(this.l2SignerOrProvider)) {
-      return this.l2SignerOrProvider
-    } else {
-      return this.l2SignerOrProvider.provider
-    }
-  }
-
-  /**
-   * Signer connected to the L1 chain.
-   */
-  get l1Signer(): Signer {
-    if (Provider.isProvider(this.l1SignerOrProvider)) {
-      throw new Error(`messenger has no L1 signer`)
-    } else {
-      return this.l1SignerOrProvider
-    }
-  }
-
-  /**
-   * Signer connected to the L2 chain.
-   */
-  get l2Signer(): Signer {
-    if (Provider.isProvider(this.l2SignerOrProvider)) {
-      throw new Error(`messenger has no L2 signer`)
-    } else {
-      return this.l2SignerOrProvider
-    }
-  }
-
-  /**
-   * Retrieves all cross chain messages sent within a given transaction.
-   *
-   * @param transaction Transaction hash or receipt to find messages from.
-   * @param opts Options object.
-   * @param opts.direction Direction to search for messages in. If not provided, will attempt to
-   * automatically search both directions under the assumption that a transaction hash will only
-   * exist on one chain. If the hash exists on both chains, will throw an error.
-   * @returns All cross chain messages sent within the transaction.
-   */
-  public async getMessagesByTransaction(
-    transaction: TransactionLike,
-    opts: {
-      direction?: MessageDirection
-    } = {}
-  ): Promise<CrossChainMessage[]> {
-    // Wait for the transaction receipt if the input is waitable.
-    await (transaction as TransactionResponse).wait?.()
-
-    // Convert the input to a transaction hash.
-    const txHash = toTransactionHash(transaction)
-
-    let receipt: TransactionReceipt
-    if (opts.direction !== undefined) {
-      // Get the receipt for the requested direction.
-      if (opts.direction === MessageDirection.L1_TO_L2) {
-        receipt = await this.l1Provider.getTransactionReceipt(txHash)
-      } else {
-        receipt = await this.l2Provider.getTransactionReceipt(txHash)
-      }
-    } else {
-      // Try both directions, starting with L1 => L2.
-      receipt = await this.l1Provider.getTransactionReceipt(txHash)
-      if (receipt) {
-        opts.direction = MessageDirection.L1_TO_L2
-      } else {
-        receipt = await this.l2Provider.getTransactionReceipt(txHash)
-        opts.direction = MessageDirection.L2_TO_L1
-      }
-    }
-
-    if (!receipt) {
-      throw new Error(`unable to find transaction receipt for ${txHash}`)
-    }
-
-    // By this point opts.direction will always be defined.
-    const messenger =
-      opts.direction === MessageDirection.L1_TO_L2
-        ? this.contracts.l1.L1CrossDomainMessenger
-        : this.contracts.l2.L2CrossDomainMessenger
-
-    return receipt.logs
-      .filter((log) => {
-        // Only look at logs emitted by the messenger address
-        return log.address === messenger.address
-      })
-      .filter((log) => {
-        // Only look at SentMessage logs specifically
-        const parsed = messenger.interface.parseLog(log)
-        return parsed.name === 'SentMessage'
-      })
-      .map((log) => {
-        // Try to pull out the value field, but only if the very next log is a SentMessageExtension1
-        // event which was introduced in the Bedrock upgrade.
-        let value = ethers.BigNumber.from(0)
-        const next = receipt.logs.find((l) => {
-          return (
-            l.logIndex === log.logIndex + 1 && l.address === messenger.address
-          )
-        })
-        if (next) {
-          const nextParsed = messenger.interface.parseLog(next)
-          if (nextParsed.name === 'SentMessageExtension1') {
-            value = nextParsed.args.value
-          }
-        }
-
-        // Convert each SentMessage log into a message object
-        const parsed = messenger.interface.parseLog(log)
-        return {
-          direction: opts.direction,
-          target: parsed.args.target,
-          sender: parsed.args.sender,
-          message: parsed.args.message,
-          messageNonce: parsed.args.messageNonce,
-          value,
-          minGasLimit: parsed.args.gasLimit,
-          logIndex: log.logIndex,
-          blockNumber: log.blockNumber,
-          transactionHash: log.transactionHash,
-        }
-      })
-  }
-
-  /**
-   * Transforms a legacy message into its corresponding Bedrock representation.
-   *
-   * @param message Legacy message to transform.
-   * @returns Bedrock representation of the message.
-   */
-  public async toBedrockCrossChainMessage(
-    message: MessageLike
-  ): Promise<CrossChainMessage> {
-    console.log('converting toBedrockCrossChainMessage', { message })
-    const resolved = await this.toCrossChainMessage(message)
-
-    // Bedrock messages are already in the correct format.
-    const { version } = decodeVersionedNonce(resolved.messageNonce)
-    if (version.eq(1)) {
-      console.log('bedrock message resolving', resolved)
-      return resolved
-    }
-
-    let value = BigNumber.from(0)
-    if (
-      resolved.direction === MessageDirection.L2_TO_L1 &&
-      resolved.sender === this.contracts.l2.L2StandardBridge.address &&
-      resolved.target === this.contracts.l1.L1StandardBridge.address
-    ) {
-      try {
-        console.log(
-          'calling contracts.l1.L1StandardBridge.interface.decodeFunctionData',
-          {
-            data: resolved.message,
-          }
-        )
-        const decodedData =
-          this.contracts.l1.L1StandardBridge.interface.decodeFunctionData(
-            'finalizeETHWithdrawal',
-            resolved.message
-          )
-        ;[, , value] = decodedData
-      } catch (err) {
-        // No problem, not a message with value.
-      }
-    }
-
-    console.log('calling migratedWithdrawalGasLimit()', resolved.message)
-    const minGasLimit = migratedWithdrawalGasLimit(resolved.message)
-
-    return {
-      ...resolved,
-      value,
-      minGasLimit,
-      messageNonce: encodeVersionedNonce(
-        BigNumber.from(1),
-        resolved.messageNonce
-      ),
-    }
-  }
-
-  /**
-   * Transforms a CrossChainMessenger message into its low-level representation inside the
-   * L2ToL1MessagePasser contract on L2.
-   *
-   * @param message Message to transform.
-   * @return Transformed message.
-   */
-  public async toLowLevelMessage(
-    message: MessageLike
-  ): Promise<LowLevelMessage> {
-    // calling toLowLevelMessgage again? why?   Likely can delete.
-    const resolved = await this.toCrossChainMessage(message)
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      throw new Error(`can only convert L2 to L1 messages to low level`)
-    }
-
-    // We may have to update the message if it's a legacy message.c
-    console.log('calling deccodeVersionNonce()', resolved.messageNonce)
-    const { version } = decodeVersionedNonce(resolved.messageNonce)
-    console.log('version', version)
-    let updated: CrossChainMessage
-    if (version.eq(0)) {
-      console.log('converting toBedrockCrossChainMessage')
-      updated = await this.toBedrockCrossChainMessage(resolved)
-    } else {
-      console.log('already a bedrock message? (bug if this line gets hit)')
-      updated = resolved
-    }
-
-    // We need to figure out the final withdrawal data that was used to compute the withdrawal hash
-    // inside the L2ToL1Message passer contract. Exact mechanism here depends on whether or not
-    // this is a legacy message or a new Bedrock message.
-    let gasLimit: BigNumber
-    let messageNonce: BigNumber
-    if (version.eq(0)) {
-      gasLimit = BigNumber.from(0)
-      messageNonce = resolved.messageNonce
-    } else {
-      console.log('in a loop getting withdrawals')
-      const receipt = await this.l2Provider.getTransactionReceipt(
-        resolved.transactionHash
-      )
-
-      const withdrawals: any[] = []
-      for (const log of receipt.logs) {
-        if (log.address === this.contracts.l2.BedrockMessagePasser.address) {
-          const decoded =
-            this.contracts.l2.L2ToL1MessagePasser.interface.parseLog(log)
-          if (decoded.name === 'MessagePassed') {
-            withdrawals.push(decoded.args)
-          }
-        }
-      }
-      console.log('withdrawals', withdrawals)
-
-      // Should not happen.
-      if (withdrawals.length === 0) {
-        throw new Error(`no withdrawals found in receipt`)
-      }
-
-      // TODO: Add support for multiple withdrawals.
-      if (withdrawals.length > 1) {
-        throw new Error(`multiple withdrawals found in receipt`)
-      }
-
-      const withdrawal = withdrawals[0]
-      messageNonce = withdrawal.nonce
-      gasLimit = withdrawal.gasLimit
-    }
-
-    return {
-      messageNonce,
-      sender: this.contracts.l2.L2CrossDomainMessenger.address,
-      target: this.contracts.l1.L1CrossDomainMessenger.address,
-      value: updated.value,
-      minGasLimit: gasLimit,
-      message: encodeCrossDomainMessageV1(
-        updated.messageNonce,
-        updated.sender,
-        updated.target,
-        updated.value,
-        updated.minGasLimit,
-        updated.message
-      ),
-    }
-  }
-
-  // public async getMessagesByAddress(
-  //   address: AddressLike,
-  //   opts?: {
-  //     direction?: MessageDirection
-  //     fromBlock?: NumberLike
-  //     toBlock?: NumberLike
-  //   }
-  // ): Promise<CrossChainMessage[]> {
-  //   throw new Error(`
-  //     The function getMessagesByAddress is currently not enabled because the sender parameter of
-  //     the SentMessage event is not indexed within the CrossChainMessenger contracts.
-  //     getMessagesByAddress will be enabled by plugging in an Optimism Indexer (coming soon).
-  //     See the following issue on GitHub for additional context:
-  //     https://github.com/ethereum-optimism/optimism/issues/2129
-  //   `)
-  // }
-
-  /**
-   * Finds the appropriate bridge adapter for a given L1<>L2 token pair. Will throw if no bridges
-   * support the token pair or if more than one bridge supports the token pair.
-   *
-   * @param l1Token L1 token address.
-   * @param l2Token L2 token address.
-   * @returns The appropriate bridge adapter for the given token pair.
-   */
-  public async getBridgeForTokenPair(
-    l1Token: AddressLike,
-    l2Token: AddressLike
-  ): Promise<IBridgeAdapter> {
-    const bridges: IBridgeAdapter[] = []
-    for (const bridge of Object.values(this.bridges)) {
-      if (await bridge.supportsTokenPair(l1Token, l2Token)) {
-        bridges.push(bridge)
-      }
-    }
-
-    if (bridges.length === 0) {
-      throw new Error(`no supported bridge for token pair`)
-    }
-
-    if (bridges.length > 1) {
-      throw new Error(`found more than one bridge for token pair`)
-    }
-
-    return bridges[0]
-  }
-
-  /**
-   * Gets all deposits for a given address.
-   *
-   * @param address Address to search for messages from.
-   * @param opts Options object.
-   * @param opts.fromBlock Block to start searching for messages from. If not provided, will start
-   * from the first block (block #0).
-   * @param opts.toBlock Block to stop searching for messages at. If not provided, will stop at the
-   * latest known block ("latest").
-   * @returns All deposit token bridge messages sent by the given address.
-   */
-  public async getDepositsByAddress(
-    address: AddressLike,
-    opts: {
-      fromBlock?: BlockTag
-      toBlock?: BlockTag
-    } = {}
-  ): Promise<TokenBridgeMessage[]> {
-    return (
-      await Promise.all(
-        Object.values(this.bridges).map(async (bridge) => {
-          return bridge.getDepositsByAddress(address, opts)
-        })
-      )
-    )
-      .reduce((acc, val) => {
-        return acc.concat(val)
-      }, [])
-      .sort((a, b) => {
-        // Sort descending by block number
-        return b.blockNumber - a.blockNumber
-      })
-  }
-
-  /**
-   * Gets all withdrawals for a given address.
-   *
-   * @param address Address to search for messages from.
-   * @param opts Options object.
-   * @param opts.fromBlock Block to start searching for messages from. If not provided, will start
-   * from the first block (block #0).
-   * @param opts.toBlock Block to stop searching for messages at. If not provided, will stop at the
-   * latest known block ("latest").
-   * @returns All withdrawal token bridge messages sent by the given address.
-   */
-  public async getWithdrawalsByAddress(
-    address: AddressLike,
-    opts: {
-      fromBlock?: BlockTag
-      toBlock?: BlockTag
-    } = {}
-  ): Promise<TokenBridgeMessage[]> {
-    return (
-      await Promise.all(
-        Object.values(this.bridges).map(async (bridge) => {
-          return bridge.getWithdrawalsByAddress(address, opts)
-        })
-      )
-    )
-      .reduce((acc, val) => {
-        return acc.concat(val)
-      }, [])
-      .sort((a, b) => {
-        // Sort descending by block number
-        return b.blockNumber - a.blockNumber
-      })
-  }
-
-  /**
-   * Resolves a MessageLike into a CrossChainMessage object.
-   * Unlike other coercion functions, this function is stateful and requires making additional
-   * requests. For now I'm going to keep this function here, but we could consider putting a
-   * similar function inside of utils/coercion.ts if people want to use this without having to
-   * create an entire CrossChainProvider object.
-   *
-   * @param message MessageLike to resolve into a CrossChainMessage.
-   * @returns Message coerced into a CrossChainMessage.
-   */
-  public async toCrossChainMessage(
-    message: MessageLike
-  ): Promise<CrossChainMessage> {
-    // TODO: Convert these checks into proper type checks.
-    if ((message as CrossChainMessage).message) {
-      return message as CrossChainMessage
-    } else if (
-      (message as TokenBridgeMessage).l1Token &&
-      (message as TokenBridgeMessage).l2Token &&
-      (message as TokenBridgeMessage).transactionHash
-    ) {
-      console.log(
-        'CrossChainMessenger.getMessgesByTransaction()',
-        (message as TokenBridgeMessage).transactionHash
-      )
-      const messages = await this.getMessagesByTransaction(
-        (message as TokenBridgeMessage).transactionHash
-      )
-      console.log(
-        'CrossChainMessenger.getMessgesByTransaction() returned',
-        messages
-      )
-
-      // The `messages` object corresponds to a list of SentMessage events that were triggered by
-      // the same transaction. We want to find the specific SentMessage event that corresponds to
-      // the TokenBridgeMessage (either a ETHDepositInitiated, ERC20DepositInitiated, or
-      // WithdrawalInitiated event). We expect the behavior of bridge contracts to be that these
-      // TokenBridgeMessage events are triggered and then a SentMessage event is triggered. Our
-      // goal here is therefore to find the first SentMessage event that comes after the input
-      // event.
-      const found = messages
-        .sort((a, b) => {
-          // Sort all messages in ascending order by log index.
-          return a.logIndex - b.logIndex
-        })
-        .find((m) => {
-          return m.logIndex > (message as TokenBridgeMessage).logIndex
-        })
-
-      if (!found) {
-        throw new Error(`could not find SentMessage event for message`)
-      }
-
-      return found
-    } else {
-      console.log('CrossChainMessenger.getMessgesByTransaction()', { message })
-      // TODO: Explicit TransactionLike check and throw if not TransactionLike
-      const messages = await this.getMessagesByTransaction(
-        message as TransactionLike
-      )
-
-      // We only want to treat TransactionLike objects as MessageLike if they only emit a single
-      // message (very common). It's unintuitive to treat a TransactionLike as a MessageLike if
-      // they emit more than one message (which message do you pick?), so we throw an error.
-      if (messages.length !== 1) {
-        throw new Error(`expected 1 message, got ${messages.length}`)
-      }
-
-      return messages[0]
-    }
-  }
-
-  /**
-   * Retrieves the status of a particular message as an enum.
-   *
-   * @param message Cross chain message to check the status of.
-   * @returns Status of the message.
-   */
-  public async getMessageStatus(message: MessageLike): Promise<MessageStatus> {
-    const resolved = await this.toCrossChainMessage(message)
-    const receipt = await this.getMessageReceipt(resolved)
-
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      if (receipt === null) {
-        return MessageStatus.UNCONFIRMED_L1_TO_L2_MESSAGE
-      } else {
-        if (receipt.receiptStatus === MessageReceiptStatus.RELAYED_SUCCEEDED) {
-          return MessageStatus.RELAYED
-        } else {
-          return MessageStatus.FAILED_L1_TO_L2_MESSAGE
-        }
-      }
-    } else {
-      if (receipt === null) {
-        let timestamp: number
-        if (this.bedrock) {
-          const output = await this.getMessageBedrockOutput(resolved)
-          if (output === null) {
-            return MessageStatus.STATE_ROOT_NOT_PUBLISHED
-          }
-
-          // Convert the message to the low level message that was proven.
-          const withdrawal = await this.toLowLevelMessage(resolved)
-
-          // Attempt to fetch the proven withdrawal.
-          const provenWithdrawal =
-            await this.contracts.l1.OptimismPortal.provenWithdrawals(
-              hashLowLevelMessage(withdrawal)
-            )
-
-          // If the withdrawal hash has not been proven on L1,
-          // return `READY_TO_PROVE`
-          if (provenWithdrawal.timestamp.eq(BigNumber.from(0))) {
-            return MessageStatus.READY_TO_PROVE
-          }
-
-          // Set the timestamp to the provenWithdrawal's timestamp
-          timestamp = provenWithdrawal.timestamp.toNumber()
-        } else {
-          const stateRoot = await this.getMessageStateRoot(resolved)
-          if (stateRoot === null) {
-            return MessageStatus.STATE_ROOT_NOT_PUBLISHED
-          }
-
-          const bn = stateRoot.batch.blockNumber
-          const block = await this.l1Provider.getBlock(bn)
-          timestamp = block.timestamp
-        }
-
-        const challengePeriod = await this.getChallengePeriodSeconds()
-        const latestBlock = await this.l1Provider.getBlock('latest')
-
-        if (timestamp + challengePeriod > latestBlock.timestamp) {
-          return MessageStatus.IN_CHALLENGE_PERIOD
-        } else {
-          return MessageStatus.READY_FOR_RELAY
-        }
-      } else {
-        if (receipt.receiptStatus === MessageReceiptStatus.RELAYED_SUCCEEDED) {
-          return MessageStatus.RELAYED
-        } else {
-          return MessageStatus.READY_FOR_RELAY
-        }
-      }
-    }
-  }
-
-  /**
-   * Finds the receipt of the transaction that executed a particular cross chain message.
-   *
-   * @param message Message to find the receipt of.
-   * @returns CrossChainMessage receipt including receipt of the transaction that relayed the
-   * given message.
-   */
-  public async getMessageReceipt(
-    message: MessageLike
-  ): Promise<MessageReceipt> {
-    const resolved = await this.toCrossChainMessage(message)
-    const messageHash = hashCrossDomainMessage(
-      resolved.messageNonce,
-      resolved.sender,
-      resolved.target,
-      resolved.value,
-      resolved.minGasLimit,
-      resolved.message
-    )
-
-    // Here we want the messenger that will receive the message, not the one that sent it.
-    const messenger =
-      resolved.direction === MessageDirection.L1_TO_L2
-        ? this.contracts.l2.L2CrossDomainMessenger
-        : this.contracts.l1.L1CrossDomainMessenger
-
-    const relayedMessageEvents = await messenger.queryFilter(
-      messenger.filters.RelayedMessage(messageHash)
-    )
-
-    // Great, we found the message. Convert it into a transaction receipt.
-    if (relayedMessageEvents.length === 1) {
-      return {
-        receiptStatus: MessageReceiptStatus.RELAYED_SUCCEEDED,
-        transactionReceipt:
-          await relayedMessageEvents[0].getTransactionReceipt(),
-      }
-    } else if (relayedMessageEvents.length > 1) {
-      // Should never happen!
-      throw new Error(`multiple successful relays for message`)
-    }
-
-    // We didn't find a transaction that relayed the message. We now attempt to find
-    // FailedRelayedMessage events instead.
-    const failedRelayedMessageEvents = await messenger.queryFilter(
-      messenger.filters.FailedRelayedMessage(messageHash)
-    )
-
-    // A transaction can fail to be relayed multiple times. We'll always return the last
-    // transaction that attempted to relay the message.
-    // TODO: Is this the best way to handle this?
-    if (failedRelayedMessageEvents.length > 0) {
-      return {
-        receiptStatus: MessageReceiptStatus.RELAYED_FAILED,
-        transactionReceipt: await failedRelayedMessageEvents[
-          failedRelayedMessageEvents.length - 1
-        ].getTransactionReceipt(),
-      }
-    }
-
-    // TODO: If the user doesn't provide enough gas then there's a chance that FailedRelayedMessage
-    // will never be triggered. We should probably fix this at the contract level by requiring a
-    // minimum amount of input gas and designing the contracts such that the gas will always be
-    // enough to trigger the event. However, for now we need a temporary way to find L1 => L2
-    // transactions that fail but don't alert us because they didn't provide enough gas.
-    // TODO: Talk with the systems and protocol team about coordinating a hard fork that fixes this
-    // on both L1 and L2.
-
-    // Just return null if we didn't find a receipt. Slightly nicer than throwing an error.
-    return null
-  }
-
-  /**
-   * Waits for a message to be executed and returns the receipt of the transaction that executed
-   * the given message.
-   *
-   * @param message Message to wait for.
-   * @param opts Options to pass to the waiting function.
-   * @param opts.confirmations Number of transaction confirmations to wait for before returning.
-   * @param opts.pollIntervalMs Number of milliseconds to wait between polling for the receipt.
-   * @param opts.timeoutMs Milliseconds to wait before timing out.
-   * @returns CrossChainMessage receipt including receipt of the transaction that relayed the
-   * given message.
-   */
-  public async waitForMessageReceipt(
-    message: MessageLike,
-    opts: {
-      confirmations?: number
-      pollIntervalMs?: number
-      timeoutMs?: number
-    } = {}
-  ): Promise<MessageReceipt> {
-    // Resolving once up-front is slightly more efficient.
-    const resolved = await this.toCrossChainMessage(message)
-
-    let totalTimeMs = 0
-    while (totalTimeMs < (opts.timeoutMs || Infinity)) {
-      const tick = Date.now()
-      const receipt = await this.getMessageReceipt(resolved)
-      if (receipt !== null) {
-        return receipt
-      } else {
-        await sleep(opts.pollIntervalMs || 4000)
-        totalTimeMs += Date.now() - tick
-      }
-    }
-
-    throw new Error(`timed out waiting for message receipt`)
-  }
-
-  /**
-   * Waits until the status of a given message changes to the expected status. Note that if the
-   * status of the given message changes to a status that implies the expected status, this will
-   * still return. If the status of the message changes to a status that exclues the expected
-   * status, this will throw an error.
-   *
-   * @param message Message to wait for.
-   * @param status Expected status of the message.
-   * @param opts Options to pass to the waiting function.
-   * @param opts.pollIntervalMs Number of milliseconds to wait when polling.
-   * @param opts.timeoutMs Milliseconds to wait before timing out.
-   */
-  public async waitForMessageStatus(
-    message: MessageLike,
-    status: MessageStatus,
-    opts: {
-      pollIntervalMs?: number
-      timeoutMs?: number
-    } = {}
-  ): Promise<void> {
-    // Resolving once up-front is slightly more efficient.
-    const resolved = await this.toCrossChainMessage(message)
-
-    let totalTimeMs = 0
-    while (totalTimeMs < (opts.timeoutMs || Infinity)) {
-      const tick = Date.now()
-      const currentStatus = await this.getMessageStatus(resolved)
-
-      // Handle special cases for L1 to L2 messages.
-      if (resolved.direction === MessageDirection.L1_TO_L2) {
-        // If we're at the expected status, we're done.
-        if (currentStatus === status) {
-          return
-        }
-
-        if (
-          status === MessageStatus.UNCONFIRMED_L1_TO_L2_MESSAGE &&
-          currentStatus > status
-        ) {
-          // Anything other than UNCONFIRMED_L1_TO_L2_MESSAGE implies that the message was at one
-          // point "unconfirmed", so we can stop waiting.
-          return
-        }
-
-        if (
-          status === MessageStatus.FAILED_L1_TO_L2_MESSAGE &&
-          currentStatus === MessageStatus.RELAYED
-        ) {
-          throw new Error(
-            `incompatible message status, expected FAILED_L1_TO_L2_MESSAGE got RELAYED`
-          )
-        }
-
-        if (
-          status === MessageStatus.RELAYED &&
-          currentStatus === MessageStatus.FAILED_L1_TO_L2_MESSAGE
-        ) {
-          throw new Error(
-            `incompatible message status, expected RELAYED got FAILED_L1_TO_L2_MESSAGE`
-          )
-        }
-      }
-
-      // Handle special cases for L2 to L1 messages.
-      if (resolved.direction === MessageDirection.L2_TO_L1) {
-        if (currentStatus >= status) {
-          // For L2 to L1 messages, anything after the expected status implies the previous status,
-          // so we can safely return if the current status enum is larger than the expected one.
-          return
-        }
-      }
-
-      await sleep(opts.pollIntervalMs || 4000)
-      totalTimeMs += Date.now() - tick
-    }
-
-    throw new Error(`timed out waiting for message status change`)
-  }
-
-  /**
-   * Estimates the amount of gas required to fully execute a given message on L2. Only applies to
-   * L1 => L2 messages. You would supply this gas limit when sending the message to L2.
-   *
-   * @param message Message get a gas estimate for.
-   * @param opts Options object.
-   * @param opts.bufferPercent Percentage of gas to add to the estimate. Defaults to 20.
-   * @param opts.from Address to use as the sender.
-   * @returns Estimates L2 gas limit.
-   */
-  public async estimateL2MessageGasLimit(
-    message: MessageRequestLike,
-    opts?: {
-      bufferPercent?: number
-      from?: string
-    }
-  ): Promise<BigNumber> {
-    let resolved: CrossChainMessage | CrossChainMessageRequest
-    let from: string
-    if ((message as CrossChainMessage).messageNonce === undefined) {
-      resolved = message as CrossChainMessageRequest
-      from = opts?.from
-    } else {
-      resolved = await this.toCrossChainMessage(message as MessageLike)
-      from = opts?.from || (resolved as CrossChainMessage).sender
-    }
-
-    // L2 message gas estimation is only used for L1 => L2 messages.
-    if (resolved.direction === MessageDirection.L2_TO_L1) {
-      throw new Error(`cannot estimate gas limit for L2 => L1 message`)
-    }
-
-    const estimate = await this.l2Provider.estimateGas({
-      from,
-      to: resolved.target,
-      data: resolved.message,
-    })
-
-    // Return the estimate plus a buffer of 20% just in case.
-    const bufferPercent = opts?.bufferPercent || 20
-    return estimate.mul(100 + bufferPercent).div(100)
-  }
-
-  /**
-   * Returns the estimated amount of time before the message can be executed. When this is a
-   * message being sent to L1, this will return the estimated time until the message will complete
-   * its challenge period. When this is a message being sent to L2, this will return the estimated
-   * amount of time until the message will be picked up and executed on L2.
-   *
-   * @param message Message to estimate the time remaining for.
-   * @returns Estimated amount of time remaining (in seconds) before the message can be executed.
-   */
-  public async estimateMessageWaitTimeSeconds(
-    message: MessageLike
-  ): Promise<number> {
-    const resolved = await this.toCrossChainMessage(message)
-    const status = await this.getMessageStatus(resolved)
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      if (
-        status === MessageStatus.RELAYED ||
-        status === MessageStatus.FAILED_L1_TO_L2_MESSAGE
-      ) {
-        // Transactions that are relayed or failed are considered completed, so the wait time is 0.
-        return 0
-      } else {
-        // Otherwise we need to estimate the number of blocks left until the transaction will be
-        // considered confirmed by the Layer 2 system. Then we multiply this by the estimated
-        // average L1 block time.
-        const receipt = await this.l1Provider.getTransactionReceipt(
-          resolved.transactionHash
-        )
-        const blocksLeft = Math.max(
-          this.depositConfirmationBlocks - receipt.confirmations,
-          0
-        )
-        return blocksLeft * this.l1BlockTimeSeconds
-      }
-    } else {
-      if (
-        status === MessageStatus.RELAYED ||
-        status === MessageStatus.READY_FOR_RELAY
-      ) {
-        // Transactions that are relayed or ready for relay are considered complete.
-        return 0
-      } else if (status === MessageStatus.STATE_ROOT_NOT_PUBLISHED) {
-        // If the state root hasn't been published yet, just assume it'll be published relatively
-        // quickly and return the challenge period for now. In the future we could use more
-        // advanced techniques to figure out average time between transaction execution and
-        // state root publication.
-        return this.getChallengePeriodSeconds()
-      } else if (status === MessageStatus.IN_CHALLENGE_PERIOD) {
-        // If the message is still within the challenge period, then we need to estimate exactly
-        // the amount of time left until the challenge period expires. The challenge period starts
-        // when the state root is published.
-        const stateRoot = await this.getMessageStateRoot(resolved)
-        const challengePeriod = await this.getChallengePeriodSeconds()
-        const targetBlock = await this.l1Provider.getBlock(
-          stateRoot.batch.blockNumber
-        )
-        const latestBlock = await this.l1Provider.getBlock('latest')
-        return Math.max(
-          challengePeriod - (latestBlock.timestamp - targetBlock.timestamp),
-          0
-        )
-      } else {
-        // Should not happen
-        throw new Error(`unexpected message status`)
-      }
-    }
-  }
-
-  /**
-   * Queries the current challenge period in seconds from the StateCommitmentChain.
-   *
-   * @returns Current challenge period in seconds.
-   */
-  public async getChallengePeriodSeconds(): Promise<number> {
-    if (!this.bedrock) {
-      return (
-        await this.contracts.l1.StateCommitmentChain.FRAUD_PROOF_WINDOW()
-      ).toNumber()
-    }
-
-    const oracleVersion = await this.contracts.l1.L2OutputOracle.version()
-    const challengePeriod =
-      oracleVersion === '1.0.0'
-        ? // The ABI in the SDK does not contain FINALIZATION_PERIOD_SECONDS
-          // in OptimismPortal, so making an explicit call instead.
-          BigNumber.from(
-            await this.contracts.l1.OptimismPortal.provider.call({
-              to: this.contracts.l1.OptimismPortal.address,
-              data: '0xf4daa291', // FINALIZATION_PERIOD_SECONDS
-            })
-          )
-        : await this.contracts.l1.L2OutputOracle.FINALIZATION_PERIOD_SECONDS()
-    return challengePeriod.toNumber()
-  }
-
-  /**
-   * Queries the OptimismPortal contract's `provenWithdrawals` mapping
-   * for a ProvenWithdrawal that matches the passed withdrawalHash
-   *
-   * @bedrock
-   * Note: This function is bedrock-specific.
-   *
-   * @returns A ProvenWithdrawal object
-   */
-  public async getProvenWithdrawal(
-    withdrawalHash: string
-  ): Promise<ProvenWithdrawal> {
-    if (!this.bedrock) {
-      throw new Error('message proving only applies after the bedrock upgrade')
-    }
-
-    return this.contracts.l1.OptimismPortal.provenWithdrawals(withdrawalHash)
-  }
-
-  /**
-   * Returns the Bedrock output root that corresponds to the given message.
-   *
-   * @param message Message to get the Bedrock output root for.
-   * @returns Bedrock output root.
-   */
-  public async getMessageBedrockOutput(
-    message: MessageLike
-  ): Promise<BedrockOutputData | null> {
-    const resolved = await this.toCrossChainMessage(message)
-
-    // Outputs are only a thing for L2 to L1 messages.
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      throw new Error(`cannot get a state root for an L1 to L2 message`)
-    }
-
-    // Try to find the output index that corresponds to the block number attached to the message.
-    // We'll explicitly handle "cannot get output" errors as a null return value, but anything else
-    // needs to get thrown. Might need to revisit this in the future to be a little more robust
-    // when connected to RPCs that don't return nice error messages.
-    let l2OutputIndex: BigNumber
-    try {
-      l2OutputIndex =
-        await this.contracts.l1.L2OutputOracle.getL2OutputIndexAfter(
-          resolved.blockNumber
-        )
-    } catch (err) {
-      if (err.message.includes('L2OutputOracle: cannot get output')) {
-        return null
-      } else {
-        throw err
-      }
-    }
-
-    // Now pull the proposal out given the output index. Should always work as long as the above
-    // codepath completed successfully.
-    const proposal = await this.contracts.l1.L2OutputOracle.getL2Output(
-      l2OutputIndex
-    )
-
-    // Format everything and return it nicely.
-    return {
-      outputRoot: proposal.outputRoot,
-      l1Timestamp: proposal.timestamp.toNumber(),
-      l2BlockNumber: proposal.l2BlockNumber.toNumber(),
-      l2OutputIndex: l2OutputIndex.toNumber(),
-    }
-  }
-
-  /**
-   * Returns the state root that corresponds to a given message. This is the state root for the
-   * block in which the transaction was included, as published to the StateCommitmentChain. If the
-   * state root for the given message has not been published yet, this function returns null.
-   *
-   * @param message Message to find a state root for.
-   * @returns State root for the block in which the message was created.
-   */
-  public async getMessageStateRoot(
-    message: MessageLike
-  ): Promise<StateRoot | null> {
-    const resolved = await this.toCrossChainMessage(message)
-
-    // State roots are only a thing for L2 to L1 messages.
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      throw new Error(`cannot get a state root for an L1 to L2 message`)
-    }
-
-    // We need the block number of the transaction that triggered the message so we can look up the
-    // state root batch that corresponds to that block number.
-    const messageTxReceipt = await this.l2Provider.getTransactionReceipt(
-      resolved.transactionHash
-    )
-
-    // Every block has exactly one transaction in it. Since there's a genesis block, the
-    // transaction index will always be one less than the block number.
-    const messageTxIndex = messageTxReceipt.blockNumber - 1
-
-    // Pull down the state root batch, we'll try to pick out the specific state root that
-    // corresponds to our message.
-    const stateRootBatch = await this.getStateRootBatchByTransactionIndex(
-      messageTxIndex
-    )
-
-    // No state root batch, no state root.
-    if (stateRootBatch === null) {
-      return null
-    }
-
-    // We have a state root batch, now we need to find the specific state root for our transaction.
-    // First we need to figure out the index of the state root within the batch we found. This is
-    // going to be the original transaction index offset by the total number of previous state
-    // roots.
-    const indexInBatch =
-      messageTxIndex - stateRootBatch.header.prevTotalElements.toNumber()
-
-    // Just a sanity check.
-    if (stateRootBatch.stateRoots.length <= indexInBatch) {
-      // Should never happen!
-      throw new Error(`state root does not exist in batch`)
-    }
-
-    return {
-      stateRoot: stateRootBatch.stateRoots[indexInBatch],
-      stateRootIndexInBatch: indexInBatch,
-      batch: stateRootBatch,
-    }
-  }
-
-  /**
-   * Returns the StateBatchAppended event that was emitted when the batch with a given index was
-   * created. Returns null if no such event exists (the batch has not been submitted).
-   *
-   * @param batchIndex Index of the batch to find an event for.
-   * @returns StateBatchAppended event for the batch, or null if no such batch exists.
-   */
-  public async getStateBatchAppendedEventByBatchIndex(
-    batchIndex: number
-  ): Promise<ethers.Event | null> {
-    const events = await this.contracts.l1.StateCommitmentChain.queryFilter(
-      this.contracts.l1.StateCommitmentChain.filters.StateBatchAppended(
-        batchIndex
-      )
-    )
-
-    if (events.length === 0) {
-      return null
-    } else if (events.length > 1) {
-      // Should never happen!
-      throw new Error(`found more than one StateBatchAppended event`)
-    } else {
-      return events[0]
-    }
-  }
-
-  /**
-   * Returns the StateBatchAppended event for the batch that includes the transaction with the
-   * given index. Returns null if no such event exists.
-   *
-   * @param transactionIndex Index of the L2 transaction to find an event for.
-   * @returns StateBatchAppended event for the batch that includes the given transaction by index.
-   */
-  public async getStateBatchAppendedEventByTransactionIndex(
-    transactionIndex: number
-  ): Promise<ethers.Event | null> {
-    const isEventHi = (event: ethers.Event, index: number) => {
-      const prevTotalElements = event.args._prevTotalElements.toNumber()
-      return index < prevTotalElements
-    }
-
-    const isEventLo = (event: ethers.Event, index: number) => {
-      const prevTotalElements = event.args._prevTotalElements.toNumber()
-      const batchSize = event.args._batchSize.toNumber()
-      return index >= prevTotalElements + batchSize
-    }
-
-    const totalBatches: ethers.BigNumber =
-      await this.contracts.l1.StateCommitmentChain.getTotalBatches()
-    if (totalBatches.eq(0)) {
-      return null
-    }
-
-    let lowerBound = 0
-    let upperBound = totalBatches.toNumber() - 1
-    let batchEvent: ethers.Event | null =
-      await this.getStateBatchAppendedEventByBatchIndex(upperBound)
-
-    // Only happens when no batches have been submitted yet.
-    if (batchEvent === null) {
-      return null
-    }
-
-    if (isEventLo(batchEvent, transactionIndex)) {
-      // Upper bound is too low, means this transaction doesn't have a corresponding state batch yet.
-      return null
-    } else if (!isEventHi(batchEvent, transactionIndex)) {
-      // Upper bound is not too low and also not too high. This means the upper bound event is the
-      // one we're looking for! Return it.
-      return batchEvent
-    }
-
-    // Binary search to find the right event. The above checks will guarantee that the event does
-    // exist and that we'll find it during this search.
-    while (lowerBound < upperBound) {
-      const middleOfBounds = Math.floor((lowerBound + upperBound) / 2)
-      batchEvent = await this.getStateBatchAppendedEventByBatchIndex(
-        middleOfBounds
-      )
-
-      if (isEventHi(batchEvent, transactionIndex)) {
-        upperBound = middleOfBounds
-      } else if (isEventLo(batchEvent, transactionIndex)) {
-        lowerBound = middleOfBounds
-      } else {
-        break
-      }
-    }
-
-    return batchEvent
-  }
-
-  /**
-   * Returns information about the state root batch that included the state root for the given
-   * transaction by index. Returns null if no such state root has been published yet.
-   *
-   * @param transactionIndex Index of the L2 transaction to find a state root batch for.
-   * @returns State root batch for the given transaction index, or null if none exists yet.
-   */
-  public async getStateRootBatchByTransactionIndex(
-    transactionIndex: number
-  ): Promise<StateRootBatch | null> {
-    const stateBatchAppendedEvent =
-      await this.getStateBatchAppendedEventByTransactionIndex(transactionIndex)
-    if (stateBatchAppendedEvent === null) {
-      return null
-    }
-
-    const stateBatchTransaction = await stateBatchAppendedEvent.getTransaction()
-    const [stateRoots] =
-      this.contracts.l1.StateCommitmentChain.interface.decodeFunctionData(
-        'appendStateBatch',
-        stateBatchTransaction.data
-      )
-
-    return {
-      blockNumber: stateBatchAppendedEvent.blockNumber,
-      stateRoots,
-      header: {
-        batchIndex: stateBatchAppendedEvent.args._batchIndex,
-        batchRoot: stateBatchAppendedEvent.args._batchRoot,
-        batchSize: stateBatchAppendedEvent.args._batchSize,
-        prevTotalElements: stateBatchAppendedEvent.args._prevTotalElements,
-        extraData: stateBatchAppendedEvent.args._extraData,
-      },
-    }
-  }
-
-  /**
-   * Generates the proof required to finalize an L2 to L1 message.
-   *
-   * @param message Message to generate a proof for.
-   * @returns Proof that can be used to finalize the message.
-   */
-  public async getMessageProof(
-    message: MessageLike
-  ): Promise<CrossChainMessageProof> {
-    const resolved = await this.toCrossChainMessage(message)
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      throw new Error(`can only generate proofs for L2 to L1 messages`)
-    }
-
-    const stateRoot = await this.getMessageStateRoot(resolved)
-    if (stateRoot === null) {
-      throw new Error(`state root for message not yet published`)
-    }
-
-    // We need to calculate the specific storage slot that demonstrates that this message was
-    // actually included in the L2 chain. The following calculation is based on the fact that
-    // messages are stored in the following mapping on L2:
-    // https://github.com/ethereum-optimism/optimism/blob/c84d3450225306abbb39b4e7d6d82424341df2be/packages/contracts/contracts/L2/predeploys/OVM_L2ToL1MessagePasser.sol#L23
-    // You can read more about how Solidity storage slots are computed for mappings here:
-    // https://docs.soliditylang.org/en/v0.8.4/internals/layout_in_storage.html#mappings-and-dynamic-arrays
-    const messageSlot = ethers.utils.keccak256(
-      ethers.utils.keccak256(
-        encodeCrossDomainMessageV0(
-          resolved.target,
-          resolved.sender,
-          resolved.message,
-          resolved.messageNonce
-        ) + remove0x(this.contracts.l2.L2CrossDomainMessenger.address)
-      ) + '00'.repeat(32)
-    )
-
-    const stateTrieProof = await makeStateTrieProof(
-      this.l2Provider as ethers.providers.JsonRpcProvider,
-      resolved.blockNumber,
-      this.contracts.l2.OVM_L2ToL1MessagePasser.address,
-      messageSlot
-    )
-
-    return {
-      stateRoot: stateRoot.stateRoot,
-      stateRootBatchHeader: stateRoot.batch.header,
-      stateRootProof: {
-        index: stateRoot.stateRootIndexInBatch,
-        siblings: makeMerkleTreeProof(
-          stateRoot.batch.stateRoots,
-          stateRoot.stateRootIndexInBatch
-        ),
-      },
-      stateTrieWitness: toHexString(rlp.encode(stateTrieProof.accountProof)),
-      storageTrieWitness: toHexString(rlp.encode(stateTrieProof.storageProof)),
-    }
-  }
-
-  /**
-   * Generates the bedrock proof required to finalize an L2 to L1 message.
-   *
-   * @param message Message to generate a proof for.
-   * @returns Proof that can be used to finalize the message.
-   */
-  public async getBedrockMessageProof(
-    message: MessageLike
-  ): Promise<BedrockCrossChainMessageProof> {
-    const resolved = await this.toCrossChainMessage(message)
-    if (resolved.direction === MessageDirection.L1_TO_L2) {
-      throw new Error(`can only generate proofs for L2 to L1 messages`)
-    }
-
-    const output = await this.getMessageBedrockOutput(resolved)
-    if (output === null) {
-      throw new Error(`state root for message not yet published`)
-    }
-
-    const withdrawal = await this.toLowLevelMessage(resolved)
-    const messageSlot = ethers.utils.keccak256(
-      ethers.utils.defaultAbiCoder.encode(
-        ['bytes32', 'uint256'],
-        [hashLowLevelMessage(withdrawal), ethers.constants.HashZero]
-      )
-    )
-
-    const stateTrieProof = await makeStateTrieProof(
-      this.l2Provider as ethers.providers.JsonRpcProvider,
-      output.l2BlockNumber,
-      this.contracts.l2.BedrockMessagePasser.address,
-      messageSlot
-    )
-
-    const block = await (
-      this.l2Provider as ethers.providers.JsonRpcProvider
-    ).send('eth_getBlockByNumber', [
-      toRpcHexString(output.l2BlockNumber),
-      false,
-    ])
-
-    return {
-      outputRootProof: {
-        version: ethers.constants.HashZero,
-        stateRoot: block.stateRoot,
-        messagePasserStorageRoot: stateTrieProof.storageRoot,
-        latestBlockhash: block.hash,
-      },
-      withdrawalProof: stateTrieProof.storageProof,
-      l2OutputIndex: output.l2OutputIndex,
-    }
-  }
-
-  /**
-   * Sends a given cross chain message. Where the message is sent depends on the direction attached
-   * to the message itself.
-   *
-   * @param message Cross chain message to send.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the message sending transaction.
-   */
-  public async sendMessage(
-    message: CrossChainMessageRequest,
-    opts?: {
-      signer?: Signer
-      l2GasLimit?: NumberLike
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    const tx = await this.populateTransaction.sendMessage(message, opts)
-    if (message.direction === MessageDirection.L1_TO_L2) {
-      return (opts?.signer || this.l1Signer).sendTransaction(tx)
-    } else {
-      return (opts?.signer || this.l2Signer).sendTransaction(tx)
-    }
-  }
-
-  /**
-   * Resends a given cross chain message with a different gas limit. Only applies to L1 to L2
-   * messages. If provided an L2 to L1 message, this function will throw an error.
-   *
-   * @param message Cross chain message to resend.
-   * @param messageGasLimit New gas limit to use for the message.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the message resending transaction.
-   */
-  public async resendMessage(
-    message: MessageLike,
-    messageGasLimit: NumberLike,
-    opts?: {
-      signer?: Signer
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.resendMessage(
-        message,
-        messageGasLimit,
-        opts
-      )
-    )
-  }
-
-  /**
-   * Proves a cross chain message that was sent from L2 to L1. Only applicable for L2 to L1
-   * messages.
-   *
-   * @param message Message to finalize.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the finalization transaction.
-   */
-  public async proveMessage(
-    message: MessageLike,
-    opts?: {
-      signer?: Signer
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    console.log('CrossChainMessenger.populateTransaction() called', {
-      message,
-      opts,
-    })
-    const proveMessageCall = await this.populateTransaction.proveMessage(
-      message,
-      opts
-    )
-    console.log('populateTransaction() return', { proveMessageCall })
-    return (opts?.signer || this.l1Signer).sendTransaction(proveMessageCall)
-  }
-
-  /**
-   * Finalizes a cross chain message that was sent from L2 to L1. Only applicable for L2 to L1
-   * messages. Will throw an error if the message has not completed its challenge period yet.
-   *
-   * @param message Message to finalize.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the finalization transaction.
-   */
-  public async finalizeMessage(
-    message: MessageLike,
-    opts?: {
-      signer?: Signer
-      overrides?: PayableOverrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.finalizeMessage(message, opts)
-    )
-  }
-
-  /**
-   * Deposits some ETH into the L2 chain.
-   *
-   * @param amount Amount of ETH to deposit (in wei).
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-   * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the deposit transaction.
-   */
-  public async depositETH(
-    amount: NumberLike,
-    opts?: {
-      recipient?: AddressLike
-      signer?: Signer
-      l2GasLimit?: NumberLike
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.depositETH(amount, opts)
-    )
-  }
-
-  /**
-   * Withdraws some ETH back to the L1 chain.
-   *
-   * @param amount Amount of ETH to withdraw.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the withdraw transaction.
-   */
-  public async withdrawETH(
-    amount: NumberLike,
-    opts?: {
-      recipient?: AddressLike
-      signer?: Signer
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l2Signer).sendTransaction(
-      await this.populateTransaction.withdrawETH(amount, opts)
-    )
-  }
-
-  /**
-   * Queries the account's approval amount for a given L1 token.
-   *
-   * @param l1Token The L1 token address.
-   * @param l2Token The L2 token address.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to get the approval for.
-   * @returns Amount of tokens approved for deposits from the account.
-   */
-  public async approval(
-    l1Token: AddressLike,
-    l2Token: AddressLike,
-    opts?: {
-      signer?: Signer
-    }
-  ): Promise<BigNumber> {
-    const bridge = await this.getBridgeForTokenPair(l1Token, l2Token)
-    return bridge.approval(l1Token, l2Token, opts?.signer || this.l1Signer)
-  }
-
-  /**
-   * Approves a deposit into the L2 chain.
-   *
-   * @param l1Token The L1 token address.
-   * @param l2Token The L2 token address.
-   * @param amount Amount of the token to approve.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the approval transaction.
-   */
-  public async approveERC20(
-    l1Token: AddressLike,
-    l2Token: AddressLike,
-    amount: NumberLike,
-    opts?: {
-      signer?: Signer
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.approveERC20(
-        l1Token,
-        l2Token,
-        amount,
-        opts
-      )
-    )
-  }
-
-  /**
-   * Deposits some ERC20 tokens into the L2 chain.
-   *
-   * @param l1Token Address of the L1 token.
-   * @param l2Token Address of the L2 token.
-   * @param amount Amount to deposit.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-   * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the deposit transaction.
-   */
-  public async depositERC20(
-    l1Token: AddressLike,
-    l2Token: AddressLike,
-    amount: NumberLike,
-    opts?: {
-      recipient?: AddressLike
-      signer?: Signer
-      l2GasLimit?: NumberLike
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l1Signer).sendTransaction(
-      await this.populateTransaction.depositERC20(
-        l1Token,
-        l2Token,
-        amount,
-        opts
-      )
-    )
-  }
-
-  /**
-   * Withdraws some ERC20 tokens back to the L1 chain.
-   *
-   * @param l1Token Address of the L1 token.
-   * @param l2Token Address of the L2 token.
-   * @param amount Amount to withdraw.
-   * @param opts Additional options.
-   * @param opts.signer Optional signer to use to send the transaction.
-   * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-   * @param opts.overrides Optional transaction overrides.
-   * @returns Transaction response for the withdraw transaction.
-   */
-  public async withdrawERC20(
-    l1Token: AddressLike,
-    l2Token: AddressLike,
-    amount: NumberLike,
-    opts?: {
-      recipient?: AddressLike
-      signer?: Signer
-      overrides?: Overrides
-    }
-  ): Promise<TransactionResponse> {
-    return (opts?.signer || this.l2Signer).sendTransaction(
-      await this.populateTransaction.withdrawERC20(
-        l1Token,
-        l2Token,
-        amount,
-        opts
-      )
-    )
-  }
-
-  /**
-   * Object that holds the functions that generate transactions to be signed by the user.
-   * Follows the pattern used by ethers.js.
-   */
-  populateTransaction = {
-    /**
-     * Generates a transaction that sends a given cross chain message. This transaction can be signed
-     * and executed by a signer.
-     *
-     * @param message Cross chain message to send.
-     * @param opts Additional options.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to send the message.
-     */
-    sendMessage: async (
-      message: CrossChainMessageRequest,
-      opts?: {
-        l2GasLimit?: NumberLike
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      if (message.direction === MessageDirection.L1_TO_L2) {
-        return this.contracts.l1.L1CrossDomainMessenger.populateTransaction.sendMessage(
-          message.target,
-          message.message,
-          opts?.l2GasLimit || (await this.estimateL2MessageGasLimit(message)),
-          opts?.overrides || {}
-        )
-      } else {
-        return this.contracts.l2.L2CrossDomainMessenger.populateTransaction.sendMessage(
-          message.target,
-          message.message,
-          0, // Gas limit goes unused when sending from L2 to L1
-          opts?.overrides || {}
-        )
-      }
-    },
-
-    /**
-     * Generates a transaction that resends a given cross chain message. Only applies to L1 to L2
-     * messages. This transaction can be signed and executed by a signer.
-     *
-     * @param message Cross chain message to resend.
-     * @param messageGasLimit New gas limit to use for the message.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to resend the message.
-     */
-    resendMessage: async (
-      message: MessageLike,
-      messageGasLimit: NumberLike,
-      opts?: {
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      const resolved = await this.toCrossChainMessage(message)
-      if (resolved.direction === MessageDirection.L2_TO_L1) {
-        throw new Error(`cannot resend L2 to L1 message`)
-      }
-
-      if (this.bedrock) {
-        return this.populateTransaction.finalizeMessage(resolved, {
-          ...(opts || {}),
-          overrides: {
-            ...opts?.overrides,
-            gasLimit: messageGasLimit,
-          },
-        })
-      } else {
-        const legacyL1XDM = new ethers.Contract(
-          this.contracts.l1.L1CrossDomainMessenger.address,
-          getContractInterface('L1CrossDomainMessenger'),
-          this.l1SignerOrProvider
-        )
-        return legacyL1XDM.populateTransaction.replayMessage(
-          resolved.target,
-          resolved.sender,
-          resolved.message,
-          resolved.messageNonce,
-          resolved.minGasLimit,
-          messageGasLimit,
-          opts?.overrides || {}
-        )
-      }
-    },
-
-    /**
-     * Generates a message proving transaction that can be signed and executed. Only
-     * applicable for L2 to L1 messages.
-     *
-     * @param message Message to generate the proving transaction for.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to prove the message.
-     */
-    proveMessage: async (
-      message: MessageLike,
-      opts?: {
-        overrides?: PayableOverrides
-      }
-    ): Promise<TransactionRequest> => {
-      console.log('CrossChainMessenger.toCrossChainMessage() called', {
-        message,
-      })
-      const resolved = await this.toCrossChainMessage(message)
-      console.log('CrossChainMessenger.toCrossChainMessage() returned', {
-        resolved,
-      })
-      if (resolved.direction === MessageDirection.L1_TO_L2) {
-        throw new Error('cannot finalize L1 to L2 message')
-      }
-
-      if (!this.bedrock) {
-        throw new Error(
-          'message proving only applies after the bedrock upgrade'
-        )
-      }
-
-      console.log('CrossChainMessenger.toLowLevelMessage() called', {
-        resolved,
-      })
-      const withdrawal = await this.toLowLevelMessage(resolved)
-      console.log('CrossChainMessenger.toLowLevelMessage() returned', {
-        withdrawal,
-      })
-      console.log('CrossChainMessenger.getBedrockMessageProof() called', {
-        resolved,
-      })
-      const proof = await this.getBedrockMessageProof(resolved)
-      console.log('CrossChainMessenger.getBedrockMessageProof() returned', {
-        proof,
-      })
-      console.log(
-        'CrossChainMessenger.populateTransaction.proveMessage() called',
-        {
-          withdrawal,
-          proof,
-        }
-      )
-      return this.contracts.l1.OptimismPortal.populateTransaction.proveWithdrawalTransaction(
-        [
-          withdrawal.messageNonce,
-          withdrawal.sender,
-          withdrawal.target,
-          withdrawal.value,
-          withdrawal.minGasLimit,
-          withdrawal.message,
-        ],
-        proof.l2OutputIndex,
-        [
-          proof.outputRootProof.version,
-          proof.outputRootProof.stateRoot,
-          proof.outputRootProof.messagePasserStorageRoot,
-          proof.outputRootProof.latestBlockhash,
-        ],
-        proof.withdrawalProof,
-        opts?.overrides || {}
-      )
-    },
-
-    /**
-     * Generates a message finalization transaction that can be signed and executed. Only
-     * applicable for L2 to L1 messages. Will throw an error if the message has not completed
-     * its challenge period yet.
-     *
-     * @param message Message to generate the finalization transaction for.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to finalize the message.
-     */
-    finalizeMessage: async (
-      message: MessageLike,
-      opts?: {
-        overrides?: PayableOverrides
-      }
-    ): Promise<TransactionRequest> => {
-      const resolved = await this.toCrossChainMessage(message)
-      if (resolved.direction === MessageDirection.L1_TO_L2) {
-        throw new Error(`cannot finalize L1 to L2 message`)
-      }
-
-      if (this.bedrock) {
-        const withdrawal = await this.toLowLevelMessage(resolved)
-        return this.contracts.l1.OptimismPortal.populateTransaction.finalizeWithdrawalTransaction(
-          [
-            withdrawal.messageNonce,
-            withdrawal.sender,
-            withdrawal.target,
-            withdrawal.value,
-            withdrawal.minGasLimit,
-            withdrawal.message,
-          ],
-          opts?.overrides || {}
-        )
-      } else {
-        // L1CrossDomainMessenger relayMessage is the only method that isn't fully backwards
-        // compatible, so we need to use the legacy interface. When we fully upgrade to Bedrock we
-        // should be able to remove this code.
-        const proof = await this.getMessageProof(resolved)
-        const legacyL1XDM = new ethers.Contract(
-          this.contracts.l1.L1CrossDomainMessenger.address,
-          getContractInterface('L1CrossDomainMessenger'),
-          this.l1SignerOrProvider
-        )
-        return legacyL1XDM.populateTransaction.relayMessage(
-          resolved.target,
-          resolved.sender,
-          resolved.message,
-          resolved.messageNonce,
-          proof,
-          opts?.overrides || {}
-        )
-      }
-    },
-
-    /**
-     * Generates a transaction for depositing some ETH into the L2 chain.
-     *
-     * @param amount Amount of ETH to deposit.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to deposit the ETH.
-     */
-    depositETH: async (
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        l2GasLimit?: NumberLike
-        overrides?: PayableOverrides
-      }
-    ): Promise<TransactionRequest> => {
-      return this.bridges.ETH.populateTransaction.deposit(
-        ethers.constants.AddressZero,
-        predeploys.OVM_ETH,
-        amount,
-        opts
-      )
-    },
-
-    /**
-     * Generates a transaction for withdrawing some ETH back to the L1 chain.
-     *
-     * @param amount Amount of ETH to withdraw.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to withdraw the ETH.
-     */
-    withdrawETH: async (
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      return this.bridges.ETH.populateTransaction.withdraw(
-        ethers.constants.AddressZero,
-        predeploys.OVM_ETH,
-        amount,
-        opts
-      )
-    },
-
-    /**
-     * Generates a transaction for approving some tokens to deposit into the L2 chain.
-     *
-     * @param l1Token The L1 token address.
-     * @param l2Token The L2 token address.
-     * @param amount Amount of the token to approve.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction response for the approval transaction.
-     */
-    approveERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      const bridge = await this.getBridgeForTokenPair(l1Token, l2Token)
-      return bridge.populateTransaction.approve(l1Token, l2Token, amount, opts)
-    },
-
-    /**
-     * Generates a transaction for depositing some ERC20 tokens into the L2 chain.
-     *
-     * @param l1Token Address of the L1 token.
-     * @param l2Token Address of the L2 token.
-     * @param amount Amount to deposit.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to deposit the tokens.
-     */
-    depositERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        l2GasLimit?: NumberLike
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      const bridge = await this.getBridgeForTokenPair(l1Token, l2Token)
-      return bridge.populateTransaction.deposit(l1Token, l2Token, amount, opts)
-    },
-
-    /**
-     * Generates a transaction for withdrawing some ERC20 tokens back to the L1 chain.
-     *
-     * @param l1Token Address of the L1 token.
-     * @param l2Token Address of the L2 token.
-     * @param amount Amount to withdraw.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction that can be signed and executed to withdraw the tokens.
-     */
-    withdrawERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        overrides?: Overrides
-      }
-    ): Promise<TransactionRequest> => {
-      const bridge = await this.getBridgeForTokenPair(l1Token, l2Token)
-      return bridge.populateTransaction.withdraw(l1Token, l2Token, amount, opts)
-    },
-  }
-
-  /**
-   * Object that holds the functions that estimates the gas required for a given transaction.
-   * Follows the pattern used by ethers.js.
-   */
-  estimateGas = {
-    /**
-     * Estimates gas required to send a cross chain message.
-     *
-     * @param message Cross chain message to send.
-     * @param opts Additional options.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    sendMessage: async (
-      message: CrossChainMessageRequest,
-      opts?: {
-        l2GasLimit?: NumberLike
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      const tx = await this.populateTransaction.sendMessage(message, opts)
-      if (message.direction === MessageDirection.L1_TO_L2) {
-        return this.l1Provider.estimateGas(tx)
-      } else {
-        return this.l2Provider.estimateGas(tx)
-      }
-    },
-
-    /**
-     * Estimates gas required to resend a cross chain message. Only applies to L1 to L2 messages.
-     *
-     * @param message Cross chain message to resend.
-     * @param messageGasLimit New gas limit to use for the message.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    resendMessage: async (
-      message: MessageLike,
-      messageGasLimit: NumberLike,
-      opts?: {
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.resendMessage(
-          message,
-          messageGasLimit,
-          opts
-        )
-      )
-    },
-
-    /**
-     * Estimates gas required to prove a cross chain message. Only applies to L2 to L1 messages.
-     *
-     * @param message Message to generate the proving transaction for.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    proveMessage: async (
-      message: MessageLike,
-      opts?: {
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.proveMessage(message, opts)
-      )
-    },
-
-    /**
-     * Estimates gas required to finalize a cross chain message. Only applies to L2 to L1 messages.
-     *
-     * @param message Message to generate the finalization transaction for.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    finalizeMessage: async (
-      message: MessageLike,
-      opts?: {
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.finalizeMessage(message, opts)
-      )
-    },
-
-    /**
-     * Estimates gas required to deposit some ETH into the L2 chain.
-     *
-     * @param amount Amount of ETH to deposit.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    depositETH: async (
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        l2GasLimit?: NumberLike
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.depositETH(amount, opts)
-      )
-    },
-
-    /**
-     * Estimates gas required to withdraw some ETH back to the L1 chain.
-     *
-     * @param amount Amount of ETH to withdraw.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    withdrawETH: async (
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l2Provider.estimateGas(
-        await this.populateTransaction.withdrawETH(amount, opts)
-      )
-    },
-
-    /**
-     * Estimates gas required to approve some tokens to deposit into the L2 chain.
-     *
-     * @param l1Token The L1 token address.
-     * @param l2Token The L2 token address.
-     * @param amount Amount of the token to approve.
-     * @param opts Additional options.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Transaction response for the approval transaction.
-     */
-    approveERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.approveERC20(
-          l1Token,
-          l2Token,
-          amount,
-          opts
-        )
-      )
-    },
-
-    /**
-     * Estimates gas required to deposit some ERC20 tokens into the L2 chain.
-     *
-     * @param l1Token Address of the L1 token.
-     * @param l2Token Address of the L2 token.
-     * @param amount Amount to deposit.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L2. Defaults to sender.
-     * @param opts.l2GasLimit Optional gas limit to use for the transaction on L2.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    depositERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        l2GasLimit?: NumberLike
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l1Provider.estimateGas(
-        await this.populateTransaction.depositERC20(
-          l1Token,
-          l2Token,
-          amount,
-          opts
-        )
-      )
-    },
-
-    /**
-     * Estimates gas required to withdraw some ERC20 tokens back to the L1 chain.
-     *
-     * @param l1Token Address of the L1 token.
-     * @param l2Token Address of the L2 token.
-     * @param amount Amount to withdraw.
-     * @param opts Additional options.
-     * @param opts.recipient Optional address to receive the funds on L1. Defaults to sender.
-     * @param opts.overrides Optional transaction overrides.
-     * @returns Gas estimate for the transaction.
-     */
-    withdrawERC20: async (
-      l1Token: AddressLike,
-      l2Token: AddressLike,
-      amount: NumberLike,
-      opts?: {
-        recipient?: AddressLike
-        overrides?: CallOverrides
-      }
-    ): Promise<BigNumber> => {
-      return this.l2Provider.estimateGas(
-        await this.populateTransaction.withdrawERC20(
-          l1Token,
-          l2Token,
-          amount,
-          opts
-        )
-      )
-    },
-  }
-}

packages/sdk/src/utils/message-utils.ts

 import { hashWithdrawal } from '@eth-optimism/core-utils'
-import { BigNumber, utils } from 'ethers'
+import { BigNumber, utils, ethers } from 'ethers'
 
 import { LowLevelMessage } from '../interfaces'
 
@@ -22,6 +22,22 @@ export const hashLowLevelMessage = (message: LowLevelMessage): string => {
   )
 }
 
+/**
+ * Utility for hashing a message hash. This computes the storage slot
+ * where the message hash will be stored in state. HashZero is used
+ * because the first mapping in the contract is used.
+ *
+ * @param messageHash Message hash to hash.
+ * @returns Hash of the given message hash.
+ */
+export const hashMessageHash = (messageHash: string): string => {
+  const data = ethers.utils.defaultAbiCoder.encode(
+    ['bytes32', 'uint256'],
+    [messageHash, ethers.constants.HashZero]
+  )
+  return ethers.utils.keccak256(data)
+}
+
 /**
  * Compute the min gas limit for a migrated withdrawal.
  */

packages/sdk/test-next/proveMessage.spec.ts

@@ -99,8 +99,10 @@ describe('prove message', () => {
 
     expect(txReceipt).toBeDefined()
 
-    expect(
-      await crossChainMessenger.proveMessage(txWithdrawalHash)
-    ).toMatchInlineSnapshot()
+    const tx = await crossChainMessenger.proveMessage(txWithdrawalHash)
+    const receipt = await tx.wait()
+
+    // A 1 means the transaction was successful
+    expect(receipt.status).toBe(1)
   }, 20_000)
 })

packages/sdk/test/utils/message-utils.spec.ts

 import { BigNumber } from 'ethers'
 
 import { expect } from '../setup'
-import { migratedWithdrawalGasLimit } from '../../src/utils/message-utils'
+import {
+  migratedWithdrawalGasLimit,
+  hashLowLevelMessage,
+  hashMessageHash,
+} from '../../src/utils/message-utils'
 
 describe('Message Utils', () => {
   describe('migratedWithdrawalGasLimit', () => {
@@ -26,4 +30,47 @@ describe('Message Utils', () => {
       }
     })
   })
+
+  /**
+   * Test that storage slot computation is correct. The test vectors are
+   * from actual migrated withdrawals on goerli.
+   */
+  describe('Withdrawal Hashing', () => {
+    it('should work', () => {
+      const tests = [
+        {
+          input: {
+            messageNonce: BigNumber.from(100000),
+            sender: '0x4200000000000000000000000000000000000007',
+            target: '0x5086d1eEF304eb5284A0f6720f79403b4e9bE294',
+            value: BigNumber.from(0),
+            minGasLimit: BigNumber.from(207744),
+            message:
+              '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',
+          },
+          result:
+            '0x7c83d39edf60c0ab61bc7cfd2e5f741efdf02fd6e2da0f12318f0d1858d3773b',
+        },
+        {
+          input: {
+            messageNonce: BigNumber.from(100001),
+            sender: '0x4200000000000000000000000000000000000007',
+            target: '0x5086d1eEF304eb5284A0f6720f79403b4e9bE294',
+            value: BigNumber.from(0),
+            minGasLimit: BigNumber.from(207744),
+            message:
+              '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',
+          },
+          result:
+            '0x17c90d87508a23d806962f4c5f366ef505e8d80e5cc2a5c87242560c21d7c588',
+        },
+      ]
+
+      for (const test of tests) {
+        const hash = hashLowLevelMessage(test.input)
+        const messageSlot = hashMessageHash(hash)
+        expect(messageSlot).to.eq(test.result)
+      }
+    })
+  })
 })