Clarinet

Clarinet is a Clarity runtime packaged as a command line tool, designed to facilitate smart contract understanding, development, testing and deployment. Clarinet consists of a Clarity REPL and a testing harness, which, when used together allow you to rapidly develop and test a Clarity smart contract, with the need to deploy the contract to a local mocknet or testnet.

Clarity is a decidable smart contract language that optimizes for predictability and security, designed by Blockstack. Smart contracts allow developers to encode essential business logic on a blockchain.

Installation

The recommended way to install Clarinet is through the Rust package manager, Cargo. Other installation methods are provided in case Cargo is not available to you.

Install from source using Cargo

You can build Clarinet from source using Cargo with the following commands:

git clone [email protected]:hirosystems/clarinet.git
cd clarinet
cargo install --path . --locked

Install from Homebrew (MacOS)

The version of Clarinet installed by Homebrew is behind the official version installed by Cargo. It is not currently recommended to install Clarinet using Homebrew.

brew install hirosystems/clarinet/clarinet

Feel free to ⭐️ this repo! With 50+ stars, this package becomes eligible to homebrew-core, at which point it will be possible automate the repo to keep the version of Clarinet installed by Homebrew up to date.

Getting started with Clarinet

The following sections describe how to create a new project in Clarinet and populate it with smart contracts. Clarinet also provides tools for interacting with your contracts in a REPL, and performing automated testing of contracts.

Create a new project

Once installed, you can use clarinet to create a new project:

clarinet new my-project && cd my-project

Clarinet will create a project directory with the following directory layout:

.
├── Clarinet.toml
├── README.md
├── contracts
├── settings
│   └── Development.toml
│   └── Mocknet.toml
└── tests

The Clarinet.toml file contains configuration for the smart contracts in your project. When you create contracts in your project, Clarinet will add them to this file.

The settings/Development.toml file contains configuration for accounts in the Clarinet console, including the seed phrases and initial balances. Initial balances are in microSTX.

Add a new contract

Clarinet can handle adding a new contract and its configuration to your project with the following command:

$ clarinet contract new bbtc

Clarinet will add 2 files to your project, the contract file in the contracts directory, and the contract test file in the tests directory.

.
├── Clarinet.toml
├── README.md
├── contracts
│   └── bbtc.clar
├── settings
│   └── Development.toml
│   └── Mocknet.toml
└── tests
    └── bbtc_test.ts

Clarinet will also add configuration to the Clarinet.toml file for your contract. You add entries to the depends_on field for each contract to indicate any contract dependencies a particular contract may have. This can be useful for contracts that implement standard traits such as for fungible tokens.

[project]
name = "my-project"
requirements = []
[contracts.bbtc]
path = "contracts/bbtc.clar"
depends_on = []

You can add contracts to your project by adding the files manually, however you must add the appropriate configuration to Clarinet.toml in order for Clarinet to recognize the contracts.

Check the syntax of your contracts

Clarinet provides a syntax checker for Clarity. You can check if your Clarity code is valid with the command:

$ clarinet check

If the Clarity code is valid, the command will return no output. If there are errors in the code, the output of the command will indicate where the errors are present.

Execute a test suite

Clarinet provides a testing harness based on Deno that can allow you to create automated unit tests or pseudo-integration tests using Typescript. Create tests in the appropriate test file, then execute them with the command:

$ clarinet test

You can review the available testing commands in the Deno Clarity library.

Load contracts in a console

The Clarinet console is an interactive Clarity REPL that runs in-memory. Any contracts in the current project are automatically loaded into memory.

$ clarinet console

You can use the ::help command in the console for a list of valid commands, which can control the state of the REPL chain, and let you advance the chain tip. Additionally, you can enter Clarity commands into the console and observe the result of the command.

You can exit the console by pressing Ctrl + C twice.

Changes to contracts are not loaded into the console while it is running. If you make any changes to your contracts you must exit the console and run it again.

Deploy contracts to mocknet

If you are running a local mocknet, you can use Clarinet to deploy your contracts to that environment for testing and evaluation on a blockchain. Use the following command:

$ clarinet deploy --mocknet