https://github.com/defi-wonderland/smock-foundry

Smock-style mocks for Foundry projects
https://github.com/defi-wonderland/smock-foundry

foundry mock smock solidity

Last synced: 3 days ago
JSON representation

Smock-style mocks for Foundry projects

• Host: GitHub
• URL: https://github.com/defi-wonderland/smock-foundry
• Owner: defi-wonderland
• License: mit
• Created: 2023-06-14T14:42:39.000Z (over 1 year ago)
• Default Branch: dev
• Last Pushed: 2024-02-21T17:21:25.000Z (11 months ago)
• Last Synced: 2024-02-22T10:24:56.477Z (11 months ago)
• Topics: foundry, mock, smock, solidity
• Language: TypeScript
• Homepage:
• Size: 615 KB
• Stars: 19
• Watchers: 2
• Forks: 0
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE
  • Codeowners: .github/CODEOWNERS

Awesome Lists containing this project

README

        
[![Version](https://img.shields.io/npm/v/@defi-wonderland/smock-foundry?label=Version)](https://www.npmjs.com/package/@defi-wonderland/smock-foundry)

[![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](https://github.com/defi-wonderland/smock-foundry/blob/dev/LICENSE)

# Smock Foundry

A plugin for [foundry](https://github.com/foundry-rs/foundry) that automatically generates Solidity mocks for every contract in your project.

## Features

- Get rid of your folder of "mock" contracts and **just use

  foundry**.

- Keep your tests **simple** with straightforward mock functions.

- Mock up external calls and internal variables in a beautiful and orderly fashion.

## Installation

You can install the plugin via yarn:

```bash

yarn add @defi-wonderland/smock-foundry --save-dev

```

## Basic Usage

### Creating mocks

To generate the mock contracts all you have to do is run:

```bash

yarn smock-foundry --contracts solidity/contracts

```

The `smock-foundry` command accepts the following options:

| Option      | Default        | Notes                                                      |

| ----------- | -------------- | ---------------------------------------------------------- |

| `contracts` | —              | The path to the solidity contracts to mock                 |

| `root`      | `.`            | The path to the root of the project                        |

| `mocks `    | `./test/smock` | The path to the generated mock contracts                   |

| `ignore`    | []             | A list of directories to ignore, e.g. `--ignore libraries` |

Be sure to `gitignore` the generated smock directory.

### Using mocks

Let's say you have a `Greeter` contract in your project at `contracts/Greeter.sol`:

```solidity

contract Greeter {

  string internal _greeting;

  constructor(string memory greeting) {

    _greeting = greeting;

  }

  function greet() public view returns (string memory) {

    return _greeting;

  }

}

```

After running the generator, you will have a mock contract located at `${mocks}/contracts/MockGreeter.sol`:

```solidity

contract MockGreeter is Greeter {

  function mock_call_greet(string memory __greeting) external {

    // Mocks the greet() function calls

  }

  function set__greeting(string memory greeting) public {

    // Sets the value of `greeting`

  }

}

```

The next step would be importing the mock contract in your unit tests, deploying it and allowing it to use the cheatcodes, specifically `vm.mockCall`.

```solidity

import 'forge-std/Test.sol';

import { MockGreeter } from '/path/to/smock/contracts/MockGreeter.sol';

import { SmockHelper } from '/path/to/smock/SmockHelper.sol';

contract BaseTest is Test, SmockHelper {

  MockGreeter public greeter;

  function setUp() public {

    // The `deployMock` call is equivalent to

    // address _greeterAddress = address(new MockGreeter('Hello'));

    // vm.label(_greeterAddress, 'Greeter');

    // vm.allowCheatcodes(_greeterAddress);

    // return _greeterAddress;

    greeter = MockGreeter(

      deployMock('Greeter', type(MockGreeter).creationCode, abi.encode('Hello'))

    );

  }

}

```

Then enjoy the wonders of mocking:

```solidity

// Mock the `greet` function to return 'Hola' instead of 'Hello'

greeter.mock_call_greet('Hola');

// Or you can achieve the same by setting the internal variable

greeter.set__greeting('Hola');

```

### Gotchas

- Please, note that if you want to mock `internal` functions, you **must** make them `virtual`. The tool will not generate mocks for internal functions that are not virtual.

- Cannot set `private` variables and mock `private` functions.

- Mocking of structs containing mappings is not supported.

- Mocking of multi-dimensional arrays of structs is not supported.

# Licensing

The primary license for Smock Foundry is MIT, see [`LICENSE`](./LICENSE).

# Contributors

Maintained with love by [Wonderland](https://defi.sucks). Made possible by viewers like you.