test: add erc20 test coverage

packages/regenesis-surgery/package.json

@@ -17,6 +17,7 @@
     "@discoveryjs/json-ext": "^0.5.3",
     "@eth-optimism/core-utils": "0.6.0",
     "@ethersproject/abstract-provider": "^5.5.1",
+    "@ethersproject/abi": "^5.5.0",
     "@ethersproject/bignumber": "^5.5.0",
     "@ethersproject/properties": "^5.5.0",
     "@ethersproject/providers": "^5.5.0",
@@ -45,7 +46,7 @@
     "mocha": "^9.1.2",
     "node-fetch": "2.6.5",
     "solc": "0.8.7-fixed",
-    "ts-node": "^10.0.0",
-    "ts-mocha": "^8.0.0"
+    "ts-mocha": "^8.0.0",
+    "ts-node": "^10.0.0"
   }
 }

packages/regenesis-surgery/scripts/classifiers.ts

@@ -13,7 +13,7 @@ import {
   DELETE_CONTRACTS,
 } from './constants'
 import { Account, AccountType, SurgeryDataSources } from './types'
-import { hexStringEqual } from './utils'
+import { hexStringEqual, isBytecodeERC20 } from './utils'
 
 export const classifiers: {
   [key in AccountType]: (account: Account, data: SurgeryDataSources) => boolean
@@ -90,6 +90,9 @@ export const classifiers: {
   [AccountType.VERIFIED]: (account, data) => {
     return !classifiers[AccountType.UNVERIFIED](account, data)
   },
+  [AccountType.ERC20]: (account) => {
+    return isBytecodeERC20(account.code)
+  },
 }
 
 export const classify = (

packages/regenesis-surgery/scripts/handlers.ts

@@ -434,4 +434,9 @@ export const handlers: {
       code: bytecode,
     }
   },
+  [AccountType.ERC20]: async (account) => {
+    throw new Error(
+      `Unexpected ERC20 classification, this should never happen: ${account.address}`
+    )
+  },
 }

packages/regenesis-surgery/scripts/types.ts

@@ -59,6 +59,7 @@ export enum AccountType {
   UNISWAP_V3_OTHER,
   UNVERIFIED,
   VERIFIED,
+  ERC20,
 }
 
 export interface UniswapPoolData {

packages/regenesis-surgery/scripts/utils.ts

 /* eslint @typescript-eslint/no-var-requires: "off" */
 import { ethers } from 'ethers'
 import { abi as UNISWAP_FACTORY_ABI } from '@uniswap/v3-core/artifacts/contracts/UniswapV3Factory.sol/UniswapV3Factory.json'
+import { Interface } from '@ethersproject/abi'
 import { parseChunked } from '@discoveryjs/json-ext'
 import { createReadStream } from 'fs'
 import * as fs from 'fs'
 import byline from 'byline'
 import * as dotenv from 'dotenv'
 import * as assert from 'assert'
-import { reqenv, getenv } from '@eth-optimism/core-utils'
+import { reqenv, getenv, remove0x } from '@eth-optimism/core-utils'
 import {
   Account,
   EtherscanContract,
@@ -114,6 +115,48 @@ export const getMappingKey = (keys: any[], slot: number) => {
   return key
 }
 
+// ERC20 interface
+const iface = new Interface([
+  'function balanceOf(address)',
+  'function name()',
+  'function symbol()',
+  'function decimals()',
+  'function totalSupply()',
+  'function transfer(address,uint256)',
+])
+
+// PUSH4 should prefix any 4 byte selector
+const PUSH4 = 0x63
+const erc20Sighashes = new Set()
+// Build the set of erc20 4 byte selectors
+for (const fn of Object.keys(iface.functions)) {
+  const sighash = iface.getSighash(fn)
+  erc20Sighashes.add(sighash)
+}
+
+export const isBytecodeERC20 = (bytecode: string): boolean => {
+  if (bytecode === '0x' || bytecode === undefined) {
+    return false
+  }
+  const seen = new Set()
+  const buf = Buffer.from(remove0x(bytecode), 'hex')
+  for (const [i, byte] of buf.entries()) {
+    // Track all of the observed 4 byte selectors that follow a PUSH4
+    // and are also present in the set of erc20Sighashes
+    if (byte === PUSH4) {
+      const sighash = '0x' + buf.slice(i + 1, i + 5).toString('hex')
+      if (erc20Sighashes.has(sighash)) {
+        seen.add(sighash)
+      }
+    }
+  }
+
+  // create a set that contains those elements of set
+  // erc20Sighashes that are not in set seen
+  const elements = [...erc20Sighashes].filter((x) => !seen.has(x))
+  return !elements.length
+}
+
 export const getUniswapV3Factory = (signerOrProvider: any): ethers.Contract => {
   return new ethers.Contract(
     UNISWAP_V3_FACTORY_ADDRESS,

packages/regenesis-surgery/test/erc20.spec.ts

+import { expect } from '@eth-optimism/core-utils/test/setup'
+import { BigNumber } from 'ethers'
+import { env } from './setup'
+
+describe('erc20', () => {
+  describe('standard ERC20', () => {
+    before(async () => {
+      await env.init()
+    })
+
+    it('ERC20s', () => {
+      for (const [i, erc20] of env.erc20s.entries()) {
+        describe(`erc20 ${i}/${env.erc20s.length} (${erc20.address})`, () => {
+          it('should have the same storage', async () => {
+            const account = env.surgeryDataSources.dump.find(
+              (a) => a.address === erc20.address
+            )
+            if (account.storage) {
+              for (const key of Object.keys(account.storage)) {
+                const pre = await env.preL2Provider.getStorageAt(
+                  account.address,
+                  BigNumber.from(key)
+                )
+                const post = await env.postL2Provider.getStorageAt(
+                  account.address,
+                  BigNumber.from(key)
+                )
+                expect(pre).to.deep.eq(post)
+              }
+            }
+          })
+        })
+      }
+    })
+  })
+})

packages/regenesis-surgery/test/provider.spec.ts

@@ -49,7 +49,7 @@ const genesis: Genesis = {
   },
 }
 
-describe.only('GenesisJsonProvider', () => {
+describe('GenesisJsonProvider', () => {
   let provider
   before(() => {
     provider = new GenesisJsonProvider(genesis)

packages/regenesis-surgery/test/setup.ts

@@ -7,7 +7,7 @@ import { getenv, remove0x } from '@eth-optimism/core-utils'
 import { providers, BigNumber } from 'ethers'
 import { SurgeryDataSources, Account, AccountType } from '../scripts/types'
 import { loadSurgeryData } from '../scripts/data'
-import { classify } from '../scripts/classifiers'
+import { classify, classifiers } from '../scripts/classifiers'
 import { GenesisJsonProvider } from './provider'
 
 // Chai plugins go here.
@@ -64,6 +64,9 @@ class TestEnv {
   // List of typed accounts in the input dump
   accounts: TypedAccount[] = []
 
+  // List of erc20 contracts in input dump
+  erc20s: Account[] = []
+
   constructor(opts: TestEnvConfig) {
     this.config = opts
     // If the pre provider url is provided, use a json rpc provider.
@@ -138,6 +141,10 @@ class TestEnv {
           ...account,
           type: accountType,
         })
+
+        if (classifiers[AccountType.ERC20](account, this.surgeryDataSources)) {
+          this.erc20s.push(account)
+        }
       }
     }
   }

packages/regenesis-surgery/test/utils.ts

+import { expect } from '@eth-optimism/core-utils/test/setup'
+import fs from 'fs/promises'
+import path from 'path'
+import { isBytecodeERC20 } from '../scripts/utils'
+
+describe('Utils', () => {
+  // Read in the mock data
+  const contracts = {}
+  before(async () => {
+    const files = await fs.readdir(path.join(__dirname, 'data'))
+    for (const filename of files) {
+      const file = await fs.readFile(path.join(__dirname, 'data', filename))
+      const name = path.parse(filename).name
+      const json = JSON.parse(file.toString())
+      contracts[name] = {
+        bytecode: json.bytecode.toString().trim(),
+        expected: json.expected,
+      }
+    }
+  })
+
+  it('isBytecodeERC20', () => {
+    for (const [name, contract] of Object.entries(contracts)) {
+      describe(`contract ${name}`, () => {
+        it('should be identified erc20', () => {
+          const result = isBytecodeERC20((contract as any).bytecode as string)
+          expect(result).to.eq((contract as any).expected)
+        })
+      })
+    }
+  })
+})

yarn.lock

@@ -734,6 +734,21 @@
     "@ethersproject/properties" "^5.4.0"
     "@ethersproject/strings" "^5.4.0"
 
+"@ethersproject/abi@^5.5.0":
+  version "5.5.0"
+  resolved "https://registry.yarnpkg.com/@ethersproject/abi/-/abi-5.5.0.tgz#fb52820e22e50b854ff15ce1647cc508d6660613"
+  integrity sha512-loW7I4AohP5KycATvc0MgujU6JyCHPqHdeoo9z3Nr9xEiNioxa65ccdm1+fsoJhkuhdRtfcL8cfyGamz2AxZ5w==
+  dependencies:
+    "@ethersproject/address" "^5.5.0"
+    "@ethersproject/bignumber" "^5.5.0"
+    "@ethersproject/bytes" "^5.5.0"
+    "@ethersproject/constants" "^5.5.0"
+    "@ethersproject/hash" "^5.5.0"
+    "@ethersproject/keccak256" "^5.5.0"
+    "@ethersproject/logger" "^5.5.0"
+    "@ethersproject/properties" "^5.5.0"
+    "@ethersproject/strings" "^5.5.0"
+
 "@ethersproject/abstract-provider@5.4.1", "@ethersproject/abstract-provider@^5.0.0", "@ethersproject/abstract-provider@^5.4.0", "@ethersproject/abstract-provider@^5.4.1":
   version "5.4.1"
   resolved "https://registry.yarnpkg.com/@ethersproject/abstract-provider/-/abstract-provider-5.4.1.tgz#e404309a29f771bd4d28dbafadcaa184668c2a6e"