fix(pre-commit): align cargo-fmt hook with CI and apply rustfmt 1.9.0

Three things needed to be fixed together for the pre-commit guard to
match what CI runs:

1. ccs-proxy/tests/store_fs.rs: re-format with rustfmt 1.9.0 (the
   version that ships with Rust 1.95 bumped in 208cfae). CI was red
   on all three platforms because of this single file.

2. .pre-commit-config.yaml: change `cargo fmt --check` to
   `cargo fmt --all -- --check`. Without `--all`, fmt only scans the
   root package and silently ignores the `ccs-proxy` workspace member,
   which is exactly why the bad commit slipped through the hook.

3. scripts/setup-pre-commit.sh + CLAUDE.md: document that we now use
   `prek` (a Rust-native, drop-in compatible replacement for the
   Python pre-commit tool) and point the setup script at it. The old
   .git/hooks/pre-commit was a hand-written shell that bypassed prek
   entirely; `prek install --overwrite` now manages the hook.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Linuxdazhao

.pre-commit-config.yaml

@@ -3,10 +3,10 @@
 repos:
   - repo: local
     hooks:
-      # Format code with rustfmt
+      # Format code with rustfmt (must match CI: `cargo fmt --all -- --check`)
       - id: cargo-fmt
         name: cargo fmt
-        entry: cargo fmt --check
+        entry: cargo fmt --all -- --check
         language: system
         types: [rust]
         pass_filenames: false

CLAUDE.md

@@ -79,23 +79,27 @@ cargo clippy -- -W warnings
 cargo audit
 ```
 
-### Pre-commit Hooks
+### Pre-commit Hooks (prek)
+
+We use [`prek`](https://github.com/j178/prek), a Rust-native drop-in
+replacement for the Python `pre-commit` tool. It reads the same
+`.pre-commit-config.yaml`.
 
 ```bash
-# One-time setup
+# One-time setup (installs prek + the git hook)
 ./scripts/setup-pre-commit.sh
 
 # Run on all files
-pre-commit run --all-files
+prek run --all-files
 
-# Run on specific files
-pre-commit run --files src/main.rs
+# Run a single hook
+prek run cargo-fmt --all-files
 
-# Update hooks
-pre-commit autoupdate
+# Update hook versions
+prek autoupdate
 
-# Uninstall hooks
-pre-commit uninstall
+# Uninstall the git hook
+prek uninstall
 ```
 
 ### Version Management and Release
@@ -451,12 +455,12 @@ cargo test -- --nocapture
 
 **Automatic Checks** (run on every commit):
 
-- `cargo check` - Compilation verification
-- `cargo fmt --check` - Code formatting
+- `cargo fmt --all -- --check` - Code formatting (matches CI; `--all` covers the whole workspace including `ccs-proxy`)
 - `cargo clippy -- -D warnings` - Linting (warnings as errors)
 - `cargo test` - All tests
 - `cargo audit` - Security vulnerability scan
 - `cargo doc --no-deps` - Documentation build
+- `cargo build --release` - Release build (artifacts cleaned after)
 
 **Setup**: `./scripts/setup-pre-commit.sh`
 

ccs-proxy/tests/store_fs.rs

@@ -134,15 +134,19 @@ async fn append_does_not_overwrite_existing_cwd() {
     store.init_session(meta).await.unwrap();
     store
         .append(rec_with_system(
-            1, "s_cwd2", "claude-opus-4-7",
+            1,
+            "s_cwd2",
+            "claude-opus-4-7",
             "Primary working directory: /first\n",
         ))
         .await
         .unwrap();
     // Second request with a different cwd marker — should be ignored.
     store
         .append(rec_with_system(
-            2, "s_cwd2", "claude-opus-4-7",
+            2,
+            "s_cwd2",
+            "claude-opus-4-7",
             "Primary working directory: /second\n",
         ))
         .await
@@ -170,14 +174,26 @@ async fn append_dedupes_and_appends_models() {
     };
     let store: Arc<dyn Store> = Arc::new(FsStore::open(dir.path().to_path_buf()).unwrap());
     store.init_session(meta).await.unwrap();
-    store.append(rec_with_system(1, "s_m", "claude-opus-4-7", "")).await.unwrap();
-    store.append(rec_with_system(2, "s_m", "claude-sonnet-4-6", "")).await.unwrap();
-    store.append(rec_with_system(3, "s_m", "claude-opus-4-7", "")).await.unwrap();
+    store
+        .append(rec_with_system(1, "s_m", "claude-opus-4-7", ""))
+        .await
+        .unwrap();
+    store
+        .append(rec_with_system(2, "s_m", "claude-sonnet-4-6", ""))
+        .await
+        .unwrap();
+    store
+        .append(rec_with_system(3, "s_m", "claude-opus-4-7", ""))
+        .await
+        .unwrap();
 
     let sessions = store.list_sessions().await.unwrap();
     assert_eq!(
         sessions[0].models,
-        vec!["claude-opus-4-7".to_string(), "claude-sonnet-4-6".to_string()]
+        vec![
+            "claude-opus-4-7".to_string(),
+            "claude-sonnet-4-6".to_string()
+        ]
     );
 }
 

scripts/setup-pre-commit.sh

@@ -1,68 +1,52 @@
 #!/bin/bash
 
-# Pre-commit setup script for cc_auto_switch
-# This script installs pre-commit and sets up the hooks
+# Pre-commit setup script for cc_auto_switch.
+# Installs `prek` (Rust-based, drop-in compatible with .pre-commit-config.yaml)
+# and wires up its hook into .git/hooks/pre-commit.
 
 set -e
 
-echo "🔧 Setting up pre-commit hooks for cc_auto_switch..."
+echo "🔧 Setting up prek hooks for cc_auto_switch..."
 
-# Check if pre-commit is installed
-if ! command -v pre-commit &> /dev/null; then
-    echo "📦 Installing pre-commit..."
-    
-    # Try different installation methods based on what's available
-    if command -v pipx &> /dev/null; then
-        echo "   Using pipx to install pre-commit..."
-        pipx install pre-commit
-    elif command -v brew &> /dev/null; then
-        echo "   Using Homebrew to install pre-commit..."
-        brew install pre-commit
-    elif command -v pip3 &> /dev/null; then
-        echo "   Using pip3 with --user flag..."
-        pip3 install --user pre-commit
-    elif command -v pip &> /dev/null; then
-        echo "   Using pip with --user flag..."
-        pip install --user pre-commit
+if ! command -v prek &> /dev/null; then
+    echo "📦 Installing prek..."
+
+    if command -v brew &> /dev/null; then
+        echo "   Using Homebrew to install prek..."
+        brew install prek
+    elif command -v cargo &> /dev/null; then
+        echo "   Using cargo to install prek..."
+        cargo install prek
     else
-        echo "❌ Error: No package manager found. Please install pre-commit manually:"
-        echo "   Option 1: brew install pre-commit"
-        echo "   Option 2: pipx install pre-commit"
-        echo "   Option 3: pip3 install --user pre-commit"
+        echo "❌ Error: No supported installer found. Install prek manually:"
+        echo "   Option 1: brew install prek"
+        echo "   Option 2: cargo install prek"
+        echo "   See https://github.com/j178/prek for other options."
         exit 1
     fi
 else
-    echo "✅ pre-commit is already installed"
+    echo "✅ prek is already installed ($(prek --version))"
 fi
 
-# Install the pre-commit hooks
-echo "🔗 Installing pre-commit hooks..."
-pre-commit install
+echo "🔗 Installing prek git hook..."
+prek install --overwrite
 
-# Verify installation
-echo "🔍 Verifying installation..."
-if pre-commit --version &> /dev/null; then
-    echo "✅ Pre-commit setup completed successfully!"
-    echo ""
-    echo "📋 Available hooks:"
-    echo "   • cargo-fmt: Code formatting check" 
-    echo "   • cargo-clippy: Linting with warnings as errors"
-    echo "   • cargo-test: Run all tests"
-    echo "   • cargo-audit: Security vulnerability scan (auto-installs if needed)"
-    echo "   • cargo-doc: Documentation build check"
-    echo "   • cargo-build-release: Release build + compile verification (removes artifacts after)"
-    echo ""
-    echo "🔄 Testing hooks (dry run)..."
-    pre-commit run --all-files --show-diff-on-failure || echo "⚠️  Some hooks may need fixes before committing"
-    echo ""
-    echo "💡 Usage:"
-    echo "   • Run manually: pre-commit run --all-files"
-    echo "   • Run on specific files: pre-commit run --files src/main.rs"
-    echo "   • Skip hooks: git commit --no-verify"
-    echo "   • Update hooks: pre-commit autoupdate"
-    echo ""
-    echo "🚀 Ready to go! All CI checks will now run locally before commits."
-else
-    echo "❌ Error: pre-commit installation failed"
-    exit 1
-fi
+echo ""
+echo "📋 Configured hooks (from .pre-commit-config.yaml):"
+echo "   • cargo-fmt: cargo fmt --all -- --check (matches CI)"
+echo "   • cargo-clippy: Linting with warnings as errors"
+echo "   • cargo-test: Run all tests"
+echo "   • cargo-audit: Security vulnerability scan (auto-installs if needed)"
+echo "   • cargo-doc: Documentation build check"
+echo "   • cargo-build-release: Release build + compile verification"
+echo ""
+echo "🔄 Dry run on all files..."
+prek run --all-files || echo "⚠️  Some hooks reported issues — fix before committing"
+echo ""
+echo "💡 Usage:"
+echo "   • Run manually: prek run --all-files"
+echo "   • Run a single hook: prek run cargo-fmt --all-files"
+echo "   • Skip hooks for one commit: git commit --no-verify"
+echo "   • Update hook versions: prek autoupdate"
+echo ""
+echo "🚀 Ready. CI-equivalent checks will run before every commit."