⚡ Bolt: Replace path().is_file() with file_type().is_some_and(|ft| ft.is_file())

.jules/bolt.md

@@ -17,3 +17,7 @@
 ## 2025-05-19 - File Discovery Allocations
 **Learning:** In `discover_importing_files`, `WalkBuilder` results were being converted to `PathBuf` via `.map(|e| e.into_path())` *before* filtering. This caused allocations for every single file in the workspace (including excluded files and directories).
 **Action:** Filter `ignore::DirEntry` directly using `entry.file_type()` and `entry.path()` before mapping to `PathBuf`. This avoids allocations for non-matching files.
+
+## 2025-06-05 - Avoid extra stat calls during directory traversal
+**Learning:** Calling `entry.path().is_file()` during directory traversal with crates like `ignore` performs an unnecessary `stat` syscall. Using `entry.file_type().is_some_and(|ft| ft.is_file())` utilizes metadata already retrieved during `readdir`, which is significantly faster.
+**Action:** When filtering files during traversal, always use the metadata provided by the directory entry (`file_type()`) rather than querying the filesystem again using the path.

crates/mill-ast/src/import_updater/file_scanner.rs

@@ -359,7 +359,8 @@ pub async fn find_project_files(
 
         for entry in walker.flatten() {
             let path = entry.path();
-            if path.is_file() {
+            // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+            if entry.file_type().is_some_and(|ft| ft.is_file()) {
                 if let Some(ext) = path.extension() {
                     let ext_str = ext.to_str().unwrap_or("");
                     // Check if any plugin handles this extension

crates/mill-handlers/src/handlers/common/checksums.rs

@@ -79,7 +79,8 @@ pub async fn calculate_checksums_for_directory_rename(
         .build();
 
     for entry in walker.flatten() {
-        if entry.path().is_file() {
+        // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+        if entry.file_type().is_some_and(|ft| ft.is_file()) {
             if let Ok(content) = context.app_state.file_service.read_file(entry.path()).await {
                 file_checksums.insert(
                     entry.path().to_string_lossy().to_string(),

crates/mill-handlers/src/handlers/lsp_adapter.rs

@@ -773,7 +773,8 @@ impl LspImportFinder for DirectLspAdapter {
         let mut files_in_dir = Vec::new();
         for entry in walker.flatten() {
             let path = entry.path();
-            if path.is_file() {
+            // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+            if entry.file_type().is_some_and(|ft| ft.is_file()) {
                 if let Some(ext) = path.extension().and_then(|e| e.to_str()) {
                     if self.extensions.contains(&ext.to_string()) {
                         files_in_dir.push(path.to_path_buf());

crates/mill-handlers/src/handlers/prune_ops.rs

@@ -665,7 +665,8 @@ impl PrunePlanner {
             let walker = ignore::WalkBuilder::new(&abs_dir).hidden(false).build();
             let files = walker
                 .flatten()
-                .filter(|entry| entry.path().is_file())
+                // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+                .filter(|entry| entry.file_type().is_some_and(|ft| ft.is_file()))
                 .map(|entry| entry.path().to_path_buf())
                 .collect();
             Ok((files, abs_dir))

crates/mill-handlers/src/handlers/rename_ops/directory_rename.rs

@@ -287,7 +287,8 @@ impl RenameService {
         let mut files_to_move = 0;
         let walker = ignore::WalkBuilder::new(&old_path).hidden(false).build();
         for entry in walker.flatten() {
-            if entry.path().is_file() {
+            // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+            if entry.file_type().is_some_and(|ft| ft.is_file()) {
                 files_to_move += 1;
             }
         }

crates/mill-services/src/services/filesystem/file_service/rename.rs

@@ -469,7 +469,8 @@ impl FileService {
         let mut files = Vec::new();
         let walker = ignore::WalkBuilder::new(dir).hidden(false).build();
         for entry in walker.flatten() {
-            if entry.path().is_file() {
+            // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+            if entry.file_type().is_some_and(|ft| ft.is_file()) {
                 files.push(entry.path().to_path_buf());
             }
         }

crates/mill-services/src/services/move_service/planner.rs

@@ -143,7 +143,10 @@ async fn append_svelte_import_edits(
 
     for entry in walker.flatten() {
         let path = entry.path();
-        if path.is_file() && path.extension().and_then(|e| e.to_str()) == Some("svelte") {
+        // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+        if entry.file_type().is_some_and(|ft| ft.is_file())
+            && path.extension().and_then(|e| e.to_str()) == Some("svelte")
+        {
             files.push(path.to_path_buf());
         }
     }
@@ -420,7 +423,8 @@ async fn plan_documentation_and_config_edits(
 
     for entry in moved_walker.flatten() {
         let path = entry.path();
-        if path.is_file() {
+        // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+        if entry.file_type().is_some_and(|ft| ft.is_file()) {
             if let Ok(relative) = path.strip_prefix(old_path) {
                 moved_files.push((path.to_path_buf(), new_path.join(relative)));
             }
@@ -455,7 +459,8 @@ async fn plan_documentation_and_config_edits(
 
     for entry in walker.flatten() {
         let path = entry.path();
-        if path.is_file() {
+        // ⚡ Bolt: Use entry.file_type() to avoid unnecessary stat syscalls
+        if entry.file_type().is_some_and(|ft| ft.is_file()) {
             if let Some(ext) = path.extension().and_then(|e| e.to_str()) {
                 if file_extensions.contains(ext) {
                     files_by_extension