Don't read the file twice

cli/commands/execute.js

@@ -245,9 +245,9 @@ async function run_non_interactively(files, argv) {
 
 exports.handler = async argv => {
     const files = [...(argv.files || []), argv.file].map(file_path => {
+        const buffer = fs.readFileSync(file_path);
         const encoding =
-            (fs
-                .readFileSync(file_path)
+            (buffer
                 .toString()
                 .split('')
                 .some(x => x.charCodeAt(0) >= 128) &&
@@ -255,7 +255,7 @@ exports.handler = async argv => {
             'utf8';
         return {
             name: path.basename(file_path),
-            content: fs.readFileSync(file_path).toString(encoding),
+            content: buffer.toString(encoding),
             encoding,
         };
     });