Formatting

Recipe	Crates	Categories
Format your Rust code with rustfmt
Configure rustfmt
Use Attributes to Skip Code Formatting in Your Code

Key Tools

Format your Rust code with rustfmt

Install rustfmt⮳ with rustup component add rustfmt

rustfmt <filename e.g. lib.rs> <main.rs> ...

# or for the whole project
cargo fmt

Using --check instructs rustfmt⮳ to exit with an error code if the input is not formatted correctly (useful for CI).

cargo fmt --all -- --check

Configure rustfmt

Create a rustfmt.toml in the project root folder. For example,

edition = "2021"
style_edition = "2021"
unstable_features = true

newline_style = "Unix"
#max_width = 100 # default: 100
use_small_heuristics = "Max"
format_code_in_doc_comments = true
indent_style = "Visual"

# Imports
imports_granularity = "Item" # or "Crate" or "Module"
imports_layout = "Vertical"
group_imports = "StdExternalCrate"

# Comments
comment_width = 100
wrap_comments = true
normalize_comments = true
normalize_doc_attributes = true

# Functions
fn_params_layout = "Compressed"

# Impl
reorder_impl_items = true

# Structs
use_field_init_shorthand = true

# Macros
use_try_shorthand = true

List config options with

rustfmt --help=config

Use Attributes to Skip Code Formatting in Your Code

For things you do not want rustfmt⮳ to mangle, use #[rustfmt::skip] , #[rustfmt::skip::macros(macro_name)] , or #![rustfmt::skip::attributes(custom_attribute)]