From 7d8cf33b01f8283c49fc7ff49e35e00efff1eb5d Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Tue, 22 Sep 2026 07:42:46 +0000
Subject: [PATCH] Parallelize file formatting with Rayon

- Use `rayon::prelude::*` to iterate over `files_to_format` in parallel using `par_iter().for_each(...)`.
- Use `std::sync::atomic::AtomicUsize` for thread-safe incrementing of `formatted_count`.
- Add `rayon` as a dependency in `cli/Cargo.toml`.

Co-authored-by: Tcode-Motion <188012755+Tcode-Motion@users.noreply.github.com>
---
 Cargo.lock              |  1 +
 cli/Cargo.toml          |  1 +
 cli/src/commands/fmt.rs | 18 ++++++++++--------
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 693f55b9..4afda75d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3867,6 +3867,7 @@ dependencies = [
  "dirs",
  "indexmap",
  "num_cpus",
+ "rayon",
  "rustyline",
  "serde",
  "serde_json",
diff --git a/cli/Cargo.toml b/cli/Cargo.toml
index 713f027b..7db8f2cf 100644
--- a/cli/Cargo.toml
+++ b/cli/Cargo.toml
@@ -42,6 +42,7 @@ bincode = "1.3.3"
 dirs = "6.0"
 num_cpus = "1.15"
 ureq = { version = "2.9" }
+rayon = "1.10.0"
 
 [build-dependencies]
 winres = "0.1.12"
diff --git a/cli/src/commands/fmt.rs b/cli/src/commands/fmt.rs
index 8cb20444..8e9ab700 100644
--- a/cli/src/commands/fmt.rs
+++ b/cli/src/commands/fmt.rs
@@ -3,7 +3,9 @@
 //! Formats TechScript source code files recursively in the specified path.
 
 use crate::exit_code::ExitCode;
+use rayon::prelude::*;
 use std::path::{Path, PathBuf};
+use std::sync::atomic::{AtomicUsize, Ordering};
 
 pub fn execute(path_str: Option<&str>) -> ExitCode {
     let current_dir = std::env::current_dir().unwrap_or_else(|_| PathBuf::from("."));
@@ -41,11 +43,11 @@ pub fn execute(path_str: Option<&str>) -> ExitCode {
         files_to_format.push(target_path);
     }
 
-    let formatter = techscript_formatter::DocumentFormatter::new(4);
-    let mut formatted_count = 0;
+    let formatted_count = AtomicUsize::new(0);
 
-    for file in files_to_format {
-        match std::fs::read_to_string(&file) {
+    files_to_format.par_iter().for_each(|file| {
+        let formatter = techscript_formatter::DocumentFormatter::new(4);
+        match std::fs::read_to_string(file) {
             Ok(content) => {
                 let formatted = formatter.format_source(&content);
                 // In skeletal phase, if format_source returns empty, we just skip writing to avoid wiping out files.
@@ -55,11 +57,11 @@ pub fn execute(path_str: Option<&str>) -> ExitCode {
                     && !formatted.contains("<stmt>")
                     && !formatted.contains("<pat>")
                 {
-                    if let Err(e) = std::fs::write(&file, formatted) {
+                    if let Err(e) = std::fs::write(file, formatted) {
                         eprintln!("Error writing formatted file {:?}: {}", file, e);
                     } else {
                         println!("Formatted: {:?}", file);
-                        formatted_count += 1;
+                        formatted_count.fetch_add(1, Ordering::Relaxed);
                     }
                 }
             }
@@ -67,8 +69,8 @@ pub fn execute(path_str: Option<&str>) -> ExitCode {
                 eprintln!("Error reading file {:?}: {}", file, e);
             }
         }
-    }
+    });
 
-    println!("Formatted {} files.", formatted_count);
+    println!("Formatted {} files.", formatted_count.into_inner());
     ExitCode::Success
 }