vscode-cmakefmt

VS Code extension for cmakefmt — a fast, correct CMake formatter written in Rust.

Features

Format document — trigger manually via the Command Palette (Format Document) or your keyboard shortcut
Format on save — opt in via VS Code's standard editor.formatOnSave setting (see below)
Config discovery — cmakefmt automatically finds the nearest .cmakefmt.yaml, .cmakefmt.yml, or .cmakefmt.toml by walking up the directory tree — no configuration needed in VS Code settings
Configurable binary path — point the extension at any cmakefmt installation
Extra arguments — pass additional flags such as --config-file

Getting started

1. Install the extension

Click Install on this page, or search for cmakefmt in the Extensions view (Ctrl+Shift+X / Cmd+Shift+X).

2. Install cmakefmt

The extension requires the cmakefmt binary. Install it using one of these methods:

Method	Command
Homebrew (macOS)	`brew install cmakefmt/cmakefmt/cmakefmt`
pip (any platform)	`pip install cmakefmt`
Cargo (any platform)	`cargo install cmakefmt-rust`
Pre-built binaries	Download from GitHub Releases

Verify the installation:

cmakefmt --version

3. Format a file

Open any CMakeLists.txt or .cmake file, then open the Command Palette (Ctrl+Shift+P / Cmd+Shift+P) and run Format Document.

To format on save, enable VS Code's built-in editor.formatOnSave (see Format on save below).

Settings

Setting	Default	Description
`cmakefmt.executablePath`	`"cmakefmt"`	Path to the `cmakefmt` binary. Only needed if `cmakefmt` is not on your `PATH`.
`cmakefmt.extraArgs`	`[]`	Extra arguments passed to `cmakefmt` (e.g. `["--config-file", "/path/to/.cmakefmt.yaml"]`).

Tip: You usually don't need extraArgs. cmakefmt discovers your project config automatically from the file being formatted. Only use --config-file if you need to override the default discovery.

Format on save

Format-on-save uses VS Code's built-in editor.formatOnSave setting. Enable it globally, or scope it to CMake files:

// .vscode/settings.json
{
  "[cmake]": {
    "editor.formatOnSave": true,
    "editor.defaultFormatter": "cmakefmt.vscode-cmakefmt"
  }
}

To disable it for CMake files only without touching the global setting, set editor.formatOnSave to false in the [cmake] scope.

Use a specific binary

If cmakefmt is not on your PATH, set the full path:

// .vscode/settings.json
{
  "cmakefmt.executablePath": "/usr/local/bin/cmakefmt"
}

Troubleshooting

"cmakefmt not found" — make sure cmakefmt is installed and on your PATH. Run cmakefmt --version in the VS Code integrated terminal to verify. If it works in your regular terminal but not in VS Code, set the full path in cmakefmt.executablePath.

Formatting does nothing — the file may have a syntax error that prevents formatting, or there is no .cmakefmt.yaml and the defaults already match your code. Check for error notifications in the bottom-right corner of VS Code after saving.

Wrong config is used — run cmakefmt config path <file> in a terminal to see which config file cmakefmt discovers for a given file.

License

MIT OR Apache-2.0 — see LICENSE.

cmakefmt