⚡ Bolt: [performance improvement] pass utf8 directly to readFileSync

packages/@expo/cli/src/utils/mergeGitIgnorePaths.ts

@@ -35,8 +35,9 @@ export function mergeGitIgnorePaths(
     return null;
   }
 
-  const targetGitIgnore = fs.readFileSync(targetGitIgnorePath).toString();
-  const sourceGitIgnore = fs.readFileSync(sourceGitIgnorePath).toString();
+  // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+  const targetGitIgnore = fs.readFileSync(targetGitIgnorePath, 'utf8');
+  const sourceGitIgnore = fs.readFileSync(sourceGitIgnorePath, 'utf8');
   const merged = mergeGitIgnoreContents(targetGitIgnore, sourceGitIgnore);
   // Only rewrite the file if it was modified.
   if (merged.contents) {

packages/@expo/config-plugins/src/android/Package.ts

@@ -125,7 +125,8 @@ export async function renameJniOnDiskForType({
   filesToUpdate.forEach((filepath: string) => {
     try {
       if (fs.lstatSync(filepath).isFile() && ['.h', '.cpp'].includes(path.extname(filepath))) {
-        let contents = fs.readFileSync(filepath).toString();
+        // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+        let contents = fs.readFileSync(filepath, 'utf8');
         contents = contents.replace(
           new RegExp(transformJavaClassDescriptor(currentPackageName).replace(/\//g, '\\/'), 'g'),
           transformJavaClassDescriptor(packageName)
@@ -207,7 +208,8 @@ export async function renamePackageOnDiskForType({
   filesToUpdate.forEach((filepath: string) => {
     try {
       if (fs.lstatSync(filepath).isFile()) {
-        let contents = fs.readFileSync(filepath).toString();
+        // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+        let contents = fs.readFileSync(filepath, 'utf8');
         if (path.extname(filepath) === '.kt') {
           contents = replacePackageName(contents, currentPackageName, kotlinSanitizedPackageName);
         } else {

packages/expo-brownfield/plugin/src/common/filesystem.ts

@@ -26,13 +26,16 @@ const maybeReadOverwrittenTemplate = (template: string, platform?: PlatformStrin
   try {
     accessSync(path.join(process.cwd(), '.brownfield-templates'));
     if (existsSync(path.join(process.cwd(), '.brownfield-templates', template))) {
-      return readFileSync(path.join(process.cwd(), '.brownfield-templates', template)).toString();
+      // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+      return readFileSync(path.join(process.cwd(), '.brownfield-templates', template), 'utf8');
     }
 
     if (existsSync(path.join(process.cwd(), '.brownfield-templates', platform ?? '.', template))) {
+      // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
       return readFileSync(
-        path.join(process.cwd(), '.brownfield-templates', platform ?? '.', template)
-      ).toString();
+        path.join(process.cwd(), '.brownfield-templates', platform ?? '.', template),
+        'utf8'
+      );
     }
     // eslint-disable-next-line no-empty
   } catch {}
@@ -55,7 +58,8 @@ const readTemplate = (template: string, platform?: PlatformString): string => {
     throw new Error(`Template ${template} doesn't exist at ${templatePath}`);
   }
 
-  return readFileSync(templatePath).toString();
+  // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+  return readFileSync(templatePath, 'utf8');
 };
 
 const createFileFromTemplateInternal = (

packages/pod-install/src/index.ts

@@ -41,7 +41,8 @@ async function runAsync(maybeProjectDirectory?: string): Promise<void> {
       process.exit(1);
     }
 
-    const jsonData = JSON.parse(readFileSync(packageJsonPath).toString());
+    // Optimization: pass 'utf8' directly to avoid intermediate buffer allocation
+    const jsonData = JSON.parse(readFileSync(packageJsonPath, 'utf8'));
     const hasExpoPackage = jsonData.dependencies?.hasOwnProperty('expo');
 
     if (hasExpoPackage) {