Introduction

Cairo lint is a static code analysis tool for the Cairo language.

It can help you improve your code quality and consistency by checking the codebase against a set of predefined rules, called lints. It can also automatically fix some of the issues found.

This tool is mostly depended on the separate lint rules. You can also read about every each of them here in the Lints section of the documentation.

Installation

Cairo lint is provided within the Scarb toolchain. You can install and download it here

Getting started

To run Cairo lint in the current project, just type:

scarb lint

This will run the code analysis and suggest places to edit your code. Running lint will yield issues like this:

$ scarb lint
  Linting hello_world v0.1.0 (/hello_world/Scarb.toml)
  warning: Plugin diagnostic: Unnecessary comparison with a boolean value. Use the variable directly.
   --> /hello_world/src/lib.cairo:2:8
    |
  2 |     if is_true() == true {
    |        -----------------
    |

To attempt to fix the issues automatically, you can run:

scarb lint --fix

You can also specify --test to perform analysis of your project's tests as well (i.e. all the Cairo code under #[cfg(test)] attributes). To learn more about available arguments, just run scarb lint --help.

Configuration

By default, most of the lints are enabled and checked, but some of them are disabled as they are much more pedantic. You can check whether a certain lint is enabled by default in the documentation. To adjust this configuration, you can manually set those values in your Scarb.toml as follows:

[tool.cairo-lint]
panic = true
bool_comparison = false

This example config will enable a panic checking lint (which is disabled by default), and disable a bool_comparison lint (which is enabled by default).