Configuring Ruff to Display Rule Numbers in VS Code

Ruff is a powerful Python linter that provides detailed information about code quality and best practices. It can be integrated with various IDEs and editors, including Visual Studio Code (VS Code). In this article, we will explore how to display rule numbers in Ruff warnings while using the Ruff VS Code extension.

Understanding Ruff Configuration

Before diving into the specifics of configuring Ruff for VS Code, it is essential to understand the basics of Ruff configuration. The ruff.toml file serves as the central configuration file for Ruff. It contains settings such as which rules to apply, ignore specific warnings, and customize the behavior of Ruff.

In the provided example, the author has enabled all rules by default using the [lint] select = ["ALL"] setting. They have also specified a list of ignored rules in the ignore field:

[lint]
select = ["ALL"]
ignore = ["PLW0603", "INP001"]

This configuration sets the stage for how Ruff will behave in the project.

Enabling Rule Numbers Display

To display rule numbers in Ruff warnings, you need to configure the ruff.path setting in your VS Code settings file (usually located at .vscode/settings.json). This setting specifies the location of the Ruff executable.

{
    "ruff.path": ["<full path to ruff in my virtual environment>"]
}

In this example, replace <full path to ruff in my virtual environment> with the actual path to the Ruff executable in your virtual environment. Ensure that the path is correct and valid for the Ruff executable.

Project Configuration

Another crucial aspect of configuring Ruff is the project configuration file (pyproject.toml). According to the Ruff documentation, Ruff expects a pyproject.toml file with specific settings in order to function correctly.

In your pyproject.toml, you should have an [tool.ruff] section that specifies your Ruff configuration. This is where you can customize various aspects of Ruff behavior, including which rules to apply and how to handle warnings:

[tool.ruff]

This is the basic structure for configuring Ruff in pyproject.toml. For more information on available settings and configurations, refer to the Ruff documentation.

Setting up VS Code Extension

To take full advantage of Ruff’s features in VS Code, you need to install the Ruff extension. You can do this by opening the Extensions panel in VS Code and searching for Ruff.

Once installed, restart VS Code or reload the window.

After installing and restarting VS Code, ensure that the Ruff extension is enabled. This will enable Ruff’s features, including linting and squiggly line indicators.

Squiggly Line Indicators

When using the Ruff VS Code extension with Python linting enabled, you should see squiggly lines inline in your code that violate Ruff rules. On hovering over these squiggly lines, a tooltip will appear showing the relevant Ruff rule code:

Ruff(C416)

This is the code for the C416 rule, which can be found on the Python documentation website. By clicking this link, you can access additional information about the C416 rule.

Conclusion

Configuring Ruff to display rule numbers in VS Code is a straightforward process that requires minimal setup. By understanding how to configure Ruff and setting up your project configuration file (pyproject.toml) correctly, you can ensure that Ruff provides accurate and detailed feedback on your code quality.

Additionally, installing the Ruff extension for VS Code will provide access to Ruff’s full range of features, including linting, squiggly line indicators, and rule documentation links. By following these steps, you can take advantage of Ruff’s capabilities to improve your coding practices and ensure that your Python projects meet high standards.

Troubleshooting Common Issues

Some common issues when configuring Ruff for VS Code include:

• Ruff executable not found: Make sure the path to the Ruff executable is correct in your settings.json file.
• Pyproject.toml configuration issues: Ensure that your pyproject.toml file has the necessary [tool.ruff] section with valid settings.
• Ruff extension not installed or enabled: Verify that you have installed and enabled the Ruff extension in VS Code.

By addressing these common issues, you can resolve problems and get Ruff working seamlessly with your VS Code environment.

Last modified on 2023-12-18