feat[smock]: add a wallet that be used to send transactions from a smock (#896)

* feat[smock]: add support for sending txs from mocks

* fix: remove unused imports

* chore: add changeset

* fix: readme errors

* Update packages/smock/README.md

* Update packages/smock/README.md
Co-authored-by: Maurelian <maurelian@protonmail.ch>
Co-authored-by: Maurelian <maurelian@protonmail.ch>

.changeset/selfish-windows-tell.md

+---
+'@eth-optimism/smock': patch
+---
+
+Adds a wallet object to smock contracts that can be used to send transactions

packages/smock/README.md

@@ -51,40 +51,6 @@ const config: HardhatUserConfig = {
 export default config
 ```
 
-## Table of Contents
-- [API](#api)
-  * [Functions](#functions)
-    + [`smockit`](#-smockit-)
-      - [Import](#import)
-      - [Signature](#signature)
-    + [`smoddit`](#-smoddit-)
-      - [Import](#import-1)
-      - [Signature](#signature-1)
-  * [Types](#types)
-    + [`smockit`](#-smockit--1)
-      - [`MockContract`](#-mockcontract-)
-      - [`MockContractFunction`](#-mockcontractfunction-)
-      - [`MockReturnValue`](#-mockreturnvalue-)
-    + [`smoddit`](#-smoddit--1)
-      - [`ModifiableContractFactory`](#-modifiablecontractfactory-)
-      - [`ModifiableContract`](#-modifiablecontract-)
-- [Examples (smockit)](#examples--smockit-)
-  * [Via `ethers.Contract`](#via--etherscontract-)
-  * [Asserting Call Count](#asserting-call-count)
-  * [Asserting Call Data](#asserting-call-data)
-  * [Returning (w/o Data)](#returning--w-o-data-)
-  * [Returning a Struct](#returning-a-struct)
-  * [Returning a Function](#returning-a-function)
-  * [Returning a Function (w/ Arguments)](#returning-a-function--w--arguments-)
-  * [Reverting (w/o Data)](#reverting--w-o-data-)
-  * [Reverting (w/ Data)](#reverting--w--data-)
-- [Examples (smoddit)](#examples--smoddit-)
-  * [Creating a Modifiable Contract](#creating-a-modifiable-contract)
-  * [Modifying a `uint256`](#modifying-a--uint256-)
-  * [Modifying a Struct](#modifying-a-struct)
-  * [Modifying a Mapping](#modifying-a-mapping)
-  * [Modifying a Nested Mapping](#modifying-a-nested-mapping)
-
 ## API
 ### Functions
 #### `smockit`
@@ -122,10 +88,13 @@ const smoddit = async (
 #### `smockit`
 ##### `MockContract`
 ```typescript
-interface MockContract extends Contract {
+interface MockContract extends ethers.Contract {
   smocked: {
     [functionName: string]: MockContractFunction
   }
+
+  // A wallet you can use to send transactions *from* a smocked contract
+  wallet: ethers.Signer
 }
 ```
 
@@ -159,14 +128,14 @@ export type MockReturnValue =
 #### `smoddit`
 ##### `ModifiableContractFactory`
 ```typescript
-interface ModifiableContractFactory extends ContractFactory {
+interface ModifiableContractFactory extends ethers.ContractFactory {
   deploy: (...args: any[]) => Promise<ModifiableContract>
 }
 ```
 
 ##### `ModifiableContract`
 ```typescript
-interface ModifiableContract extends Contract {
+interface ModifiableContract extends ethers.Contract {
   smodify: {
     put: (storage: any) => Promise<void>
   }
@@ -339,6 +308,20 @@ MyMockContract.smocked.myFunction.will.revert.with('0x1234')
 console.log(await MyMockContract.myFunction('Some return value!')) // Revert!
 ```
 
+### Sending transactions from a smocked contract
+```typescript
+import { ethers } from 'hardhat'
+import { smockit } from '@eth-optimism/smock'
+
+const myContractFactory = await ethers.getContractFactory('MyContract')
+const myContract = await myContractFactory.deploy(...)
+
+// Smockit!
+const mock = await smockit('AnotherContract')
+
+await myContract.connect(mock.wallet).doSomeFunction() // msg.sender == mock.address
+```
+
 ## Examples (smoddit)
 
 ### Creating a Modifiable Contract

packages/smock/package.json

@@ -17,6 +17,9 @@
     "clean": "rimraf ./artifacts ./cache ./dist ./tsconfig.build.tsbuildinfo"
   },
   "peerDependencies": {
+    "@ethersproject/abi": "^5",
+    "@ethersproject/abstract-provider": "^5",
+    "@ethersproject/abstract-signer": "^5",
     "@nomiclabs/ethereumjs-vm": "^4",
     "@nomiclabs/hardhat-ethers": "^2",
     "ethers": "^5",
@@ -24,11 +27,12 @@
   },
   "dependencies": {
     "@eth-optimism/core-utils": "^0.4.1",
-    "@ethersproject/abi": "^5.0.13",
-    "@ethersproject/abstract-provider": "^5.0.10",
     "bn.js": "^5.2.0"
   },
   "devDependencies": {
+    "@ethersproject/abi": "^5.1.2",
+    "@ethersproject/abstract-provider": "^5.1.0",
+    "@ethersproject/abstract-signer": "^5.1.0",
     "@nomiclabs/ethereumjs-vm": "^4.2.2",
     "@nomiclabs/hardhat-ethers": "^2.0.2",
     "@nomiclabs/hardhat-waffle": "^2.0.1",

packages/smock/src/smockit/smockit.ts

@@ -162,6 +162,17 @@ export const smockit = async (
     opts.provider || (hre as any).ethers.provider // TODO: Probably check that this exists.
   ) as MockContract
 
+  // We attach a wallet to the contract so that users can send transactions *from* a smock.
+  await hre.network.provider.request({
+    method: 'hardhat_impersonateAccount',
+    params: [contract.address]
+  })
+
+  // Now we actually get the signer and attach it to the mock.
+  contract.wallet = await (hre as any).ethers.getSigner(
+    contract.address
+  )
+
   // Start by smocking the fallback.
   contract.smocked = {
     fallback: smockifyFunction(

packages/smock/src/smockit/types.ts

 /* Imports: External */
 import { Artifact } from 'hardhat/types'
 import { Contract, ContractFactory, ethers } from 'ethers'
+import { Signer } from '@ethersproject/abstract-signer'
 import { Provider } from '@ethersproject/abstract-provider'
 import { JsonFragment, Fragment } from '@ethersproject/abi'
 
@@ -47,6 +48,8 @@ export type MockContract = Contract & {
   smocked: {
     [name: string]: MockContractFunction
   }
+
+  wallet: Signer
 }
 
 export interface SmockedVM {

packages/smock/test/contracts/TestHelpers_SenderAssertions.sol

+// SPDX-License-Identifier: MIT
+pragma solidity ^0.7.0;
+
+contract TestHelpers_SenderAssertions {
+    function getSender()
+        public
+        view
+        returns (
+            address
+        )
+    {
+        return msg.sender;
+    }
+}

packages/smock/test/smockit/sending-from-mocks.spec.ts

+/* Imports: External */
+import hre from 'hardhat'
+import { expect } from 'chai'
+import { Contract } from 'ethers'
+
+/* Imports: Internal */
+import { smockit } from '../../src'
+
+describe('[smock]: sending transactions from smock contracts', () => {
+  const ethers = (hre as any).ethers
+
+  let TestHelpers_SenderAssertions: Contract
+  before(async () => {
+    TestHelpers_SenderAssertions = await(
+      await ethers.getContractFactory(
+        'TestHelpers_SenderAssertions'
+      )
+    ).deploy()
+  })
+
+  it('should attach a signer for a mock with a random address', async () => {
+    const mock = await smockit('TestHelpers_BasicReturnContract')
+    
+    expect(
+      await TestHelpers_SenderAssertions.connect(mock.wallet).getSender()
+    ).to.equal(mock.address)
+  })
+
+  it('should attach a signer for a mock with a fixed address', async () => {
+    const mock = await smockit('TestHelpers_BasicReturnContract', {
+      address: '0x1234123412341234123412341234123412341234'
+    })
+
+    expect(
+      await TestHelpers_SenderAssertions.connect(mock.wallet).getSender()
+    ).to.equal(mock.address)
+  })
+})

yarn.lock

@@ -992,7 +992,7 @@
     "@ethersproject/properties" "^5.0.3"
     "@ethersproject/strings" "^5.0.4"
 
-"@ethersproject/abi@5.1.0", "@ethersproject/abi@^5.0.0", "@ethersproject/abi@^5.0.1", "@ethersproject/abi@^5.0.13", "@ethersproject/abi@^5.0.2", "@ethersproject/abi@^5.1.0":
+"@ethersproject/abi@5.1.0", "@ethersproject/abi@^5.0.0", "@ethersproject/abi@^5.0.1", "@ethersproject/abi@^5.0.2", "@ethersproject/abi@^5.1.0":
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/@ethersproject/abi/-/abi-5.1.0.tgz#d582c9f6a8e8192778b5f2c991ce19d7b336b0c5"
   integrity sha512-N/W9Sbn1/C6Kh2kuHRjf/hX6euMK4+9zdJRBB8sDWmihVntjUAfxbusGZKzDQD8i3szAHhTz8K7XADV5iFNfJw==
@@ -1007,7 +1007,7 @@
     "@ethersproject/properties" "^5.1.0"
     "@ethersproject/strings" "^5.1.0"
 
-"@ethersproject/abi@^5.0.0-beta.146":
+"@ethersproject/abi@5.1.2", "@ethersproject/abi@^5.0.0-beta.146", "@ethersproject/abi@^5.1.2":
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/@ethersproject/abi/-/abi-5.1.2.tgz#a8e75cd0455e6dc9e4861c3d1c22bbe436c1d775"
   integrity sha512-uMhoQVPX0UtfzTpekYQSEUcJGDgsJ25ifz+SV6PDETWaUFhcR8RNgb1QPTASP13inW8r6iy0/Xdq9D5hK2pNvA==
@@ -1022,7 +1022,7 @@
     "@ethersproject/properties" "^5.1.0"
     "@ethersproject/strings" "^5.1.0"
 
-"@ethersproject/abstract-provider@5.1.0", "@ethersproject/abstract-provider@^5.0.0", "@ethersproject/abstract-provider@^5.0.10", "@ethersproject/abstract-provider@^5.0.5", "@ethersproject/abstract-provider@^5.0.8", "@ethersproject/abstract-provider@^5.0.9", "@ethersproject/abstract-provider@^5.1.0":
+"@ethersproject/abstract-provider@5.1.0", "@ethersproject/abstract-provider@^5.0.0", "@ethersproject/abstract-provider@^5.0.5", "@ethersproject/abstract-provider@^5.0.8", "@ethersproject/abstract-provider@^5.0.9", "@ethersproject/abstract-provider@^5.1.0":
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/@ethersproject/abstract-provider/-/abstract-provider-5.1.0.tgz#1f24c56cda5524ef4ed3cfc562a01d6b6f8eeb0b"
   integrity sha512-8dJUnT8VNvPwWhYIau4dwp7qe1g+KgdRm4XTWvjkI9gAT2zZa90WF5ApdZ3vl1r6NDmnn6vUVvyphClRZRteTQ==
@@ -1314,6 +1314,21 @@
     "@ethersproject/rlp" "^5.1.0"
     "@ethersproject/signing-key" "^5.1.0"
 
+"@ethersproject/transactions@5.1.1", "@ethersproject/transactions@^5.0.21":
+  version "5.1.1"
+  resolved "https://registry.yarnpkg.com/@ethersproject/transactions/-/transactions-5.1.1.tgz#5a6bbb25fb062c3cc75eb0db12faefcdd3870813"
+  integrity sha512-Nwgbp09ttIVN0OoUBatCXaHxR7grWPHbozJN8v7AXDLrl6nnOIBEMDh+yJTnosSQlFhcyjfTGGN+Mx6R8HdvMw==
+  dependencies:
+    "@ethersproject/address" "^5.1.0"
+    "@ethersproject/bignumber" "^5.1.0"
+    "@ethersproject/bytes" "^5.1.0"
+    "@ethersproject/constants" "^5.1.0"
+    "@ethersproject/keccak256" "^5.1.0"
+    "@ethersproject/logger" "^5.1.0"
+    "@ethersproject/properties" "^5.1.0"
+    "@ethersproject/rlp" "^5.1.0"
+    "@ethersproject/signing-key" "^5.1.0"
+
 "@ethersproject/units@5.1.0", "@ethersproject/units@^5.0.0":
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/@ethersproject/units/-/units-5.1.0.tgz#b6ab3430ebc22adc3cb4839516496f167bee3ad5"