From 569c94b71b29e4a49aaf95ae5da9a56c19714f1e Mon Sep 17 00:00:00 2001
From: Douglas Creager <dcreager@dcreager.net>
Date: Mon, 19 May 2025 11:40:58 -0400
Subject: [PATCH] Add rustfmt.toml file (#18197)

My editor runs `rustfmt` on save to format Rust code, not `cargo fmt`.

With our recent bump to the Rust 2024 edition, the formatting that
`rustfmt`/`cargo fmt` applies changed. Unfortunately, `rustfmt` and
`cargo fmt` have different behaviors for determining which edition to
use when formatting: `cargo fmt` looks for the Rust edition in
`Cargo.toml`, whereas `rustfmt` looks for it in `rustfmt.toml`. As a
result, whenever I save, I have to remember to manually run `cargo fmt`
before committing/pushing.

There is an open issue asking for `rustfmt` to also look at `Cargo.toml`
when it's present (https://github.com/rust-lang/rust.vim/issues/368),
but it seems like they "closed" that issue just by bumping the default
edition (six years ago, from 2015 to 2018).

In the meantime, this PR adds a `rustfmt.toml` file with our current
Rust edition so that both invocation have the same behavior. I don't
love that this duplicates information in `Cargo.toml`, but I've added a
reminder comment there to hopefully ensure that we bump the edition in
both places three years from now.
---
 Cargo.toml                                  | 1 +
 crates/ruff_text_size/Cargo.toml            | 9 +++++++--
 crates/ruff_text_size/src/schemars_impls.rs | 2 +-
 crates/ruff_text_size/src/serde_impls.rs    | 2 +-
 crates/ruff_text_size/tests/serde.rs        | 2 +-
 rustfmt.toml                                | 2 ++
 6 files changed, 13 insertions(+), 5 deletions(-)
 create mode 100644 rustfmt.toml

diff --git a/Cargo.toml b/Cargo.toml
index 6f9c967b78..7461248654 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,7 @@ members = ["crates/*"]
 resolver = "2"
 
 [workspace.package]
+# Please update rustfmt.toml when bumping the Rust edition
 edition = "2024"
 rust-version = "1.85"
 homepage = "https://docs.astral.sh/ruff"
diff --git a/crates/ruff_text_size/Cargo.toml b/crates/ruff_text_size/Cargo.toml
index d51954503b..19de486464 100644
--- a/crates/ruff_text_size/Cargo.toml
+++ b/crates/ruff_text_size/Cargo.toml
@@ -2,8 +2,13 @@
 name = "ruff_text_size"
 version = "0.0.0"
 publish = false
-edition = "2021"
-rust-version = "1.67.1"
+authors = { workspace = true }
+edition = { workspace = true }
+rust-version = { workspace = true }
+homepage = { workspace = true }
+documentation = { workspace = true }
+repository = { workspace = true }
+license = { workspace = true }
 
 [dependencies]
 serde = { workspace = true, optional = true }
diff --git a/crates/ruff_text_size/src/schemars_impls.rs b/crates/ruff_text_size/src/schemars_impls.rs
index 0a594d21c0..4bc9ba2e01 100644
--- a/crates/ruff_text_size/src/schemars_impls.rs
+++ b/crates/ruff_text_size/src/schemars_impls.rs
@@ -6,7 +6,7 @@
 //! bindings to the Workspace API
 
 use crate::{TextRange, TextSize};
-use schemars::{r#gen::SchemaGenerator, schema::Schema, JsonSchema};
+use schemars::{JsonSchema, r#gen::SchemaGenerator, schema::Schema};
 
 impl JsonSchema for TextSize {
     fn schema_name() -> String {
diff --git a/crates/ruff_text_size/src/serde_impls.rs b/crates/ruff_text_size/src/serde_impls.rs
index 42e0017ec0..7558e9769e 100644
--- a/crates/ruff_text_size/src/serde_impls.rs
+++ b/crates/ruff_text_size/src/serde_impls.rs
@@ -1,6 +1,6 @@
 use {
     crate::{TextRange, TextSize},
-    serde::{de, Deserialize, Deserializer, Serialize, Serializer},
+    serde::{Deserialize, Deserializer, Serialize, Serializer, de},
 };
 
 impl Serialize for TextSize {
diff --git a/crates/ruff_text_size/tests/serde.rs b/crates/ruff_text_size/tests/serde.rs
index 0d8f9d4a6a..606b416833 100644
--- a/crates/ruff_text_size/tests/serde.rs
+++ b/crates/ruff_text_size/tests/serde.rs
@@ -1,6 +1,6 @@
 use {
     ruff_text_size::{TextRange, TextSize},
-    serde_test::{assert_de_tokens_error, assert_tokens, Token},
+    serde_test::{Token, assert_de_tokens_error, assert_tokens},
     std::ops,
 };
 
diff --git a/rustfmt.toml b/rustfmt.toml
new file mode 100644
index 0000000000..f3e454b618
--- /dev/null
+++ b/rustfmt.toml
@@ -0,0 +1,2 @@
+edition = "2024"
+style_edition = "2024"