add rustfmt settings file

Author: tshepang

examples/rustc-driver-example.rs

@@ -20,7 +20,7 @@ use std::path::Path;
 use std::sync::Arc;
 
 use rustc_ast_pretty::pprust::item_to_string;
-use rustc_driver::{run_compiler, Compilation};
+use rustc_driver::{Compilation, run_compiler};
 use rustc_interface::interface::{Compiler, Config};
 use rustc_middle::ty::TyCtxt;
 

examples/rustc-driver-interacting-with-the-ast.rs

@@ -20,7 +20,7 @@ use std::path::Path;
 use std::sync::Arc;
 
 use rustc_ast_pretty::pprust::item_to_string;
-use rustc_driver::{run_compiler, Compilation};
+use rustc_driver::{Compilation, run_compiler};
 use rustc_interface::interface::{Compiler, Config};
 use rustc_middle::ty::TyCtxt;
 

rustfmt.toml

@@ -0,0 +1,7 @@
+# matches that of rust-lang/rust
+style_edition = "2024"
+use_small_heuristics = "Max"
+merge_derives = false
+group_imports = "StdExternalCrate"
+imports_granularity = "Module"
+use_field_init_shorthand = true