rust-lang/rustfmt
Rustfmt
rustfmt is a Rust code formatter that operates as a Cargo subcommand, applying consistent formatting to Rust source files according to official style guidelines. It parses source code into a syntax tree, applies formatting rules to tree nodes, and pretty-prints the result back to text, with support for TOML-driven configuration that allows per-project style customization.
The formatter is edition-aware, automatically selecting formatting rules based on the Rust edition specified in the project, and supports a style edition override that decouples formatting rules from the Rust edition used for parsing. It includes a nightly style preview mechanism for testing upcoming formatting styles before they are stabilized, and a check-mode compliance enforcement that compares formatted output to original input, returning a non-zero exit code when differences exist.
The tool integrates with CI pipelines to enforce formatting compliance, failing builds automatically when pull request code does not match configured rules. It also supports editor integration for formatting Rust source files directly from within code editors, and can format all binary and library targets in a crate or workspace via a single cargo command.
Features
- Code Formatting Tools - Applies consistent formatting to Rust source files according to official style guidelines and project configuration.
- Source Code Formatters - Applies consistent formatting to Rust source files according to official style guidelines and project-specific configuration.
- Rust Code Formatters - Applies consistent, project-wide formatting to Rust source files according to official style guidelines.
- Cargo Subcommand Formatters - Integrates with Cargo as a subcommand to format all crate and workspace targets.
- Cargo Subcommand Formatters - Runs formatting on all binary and library targets of a crate or workspace via cargo fmt.
- Concrete Syntax Tree Generators - Parses source code into a concrete syntax tree for formatting and pretty-printing.
- Cargo Subcommand Integrations - Integrates with Cargo to format all crate and workspace targets via a single command.
- Cargo Workspace Formatters - Runs formatting across all targets in a Rust crate or workspace using a single cargo command.
- CI Formatting Checks - Checks formatting compliance in automated pipelines and fails builds when code does not match style rules.
- Source File Evaluation - Reads Rust source files and reformats them in place according to official style guidelines.
- Editor Formatting Integrations - Integrates with popular editors to format Rust source files directly from the editing environment.
- Edition-Aware Formatting Rules - Adjusts formatting rules to match the Rust edition specified in the project with optional style edition override.
- Edition-Aware Formatting Selectors - Automatically selects formatting rules based on the Rust edition specified in the project.
- Formatting Configurations - Reads formatting options from a TOML configuration file placed in the project or any parent directory.
- Formatting Compliance Modes - Provides a check mode that exits with non-zero when formatting changes are needed.
- TOML Configuration Support - Reads formatting options from a TOML configuration file for per-project style customization.
- Edition-Specific Formatting Rules - Applies the default Rust formatting style that corresponds to the project's Rust edition, varying rules per edition.
- Code Formatters - Official Rust code formatter.
- Code Formatting - Official code formatter maintained by the core language team.
- Rust Projects - Listed in the “Rust Projects” section of the Awesome For Beginners awesome list.
- Static Analysis Tools - Formats Rust code to style guidelines.
