refactor: simplify the resolve entry path logic

Signed-off-by: Camila Belo <camilaibs@gmail.com>

packages/cli/src/modules/build/commands/package/start/startPackage.test.ts

@@ -46,12 +46,12 @@ describe('resolveEntryPath', () => {
 
   it('should handle multiple dots in filename', () => {
     mockDir.setContent({
-      'file.backup.old.ts': 'export const data = {};',
+      'index.alpha.ts': 'export const data = {};',
     });
 
-    const result = resolveEntryPath('file.backup.old.ts', mockDir.path);
+    const result = resolveEntryPath('index.alpha.ts', mockDir.path);
 
-    expect(result).toBe('file.backup.old');
+    expect(result).toBe('index.alpha');
   });
 
   it('should handle simple directory names', () => {

packages/cli/src/modules/build/commands/package/start/startPackage.ts

@@ -17,21 +17,19 @@
 import { PackageRole } from '@backstage/cli-node';
 import { startBackend, startBackendPlugin } from './startBackend';
 import { startFrontend } from './startFrontend';
-import { statSync, readdirSync } from 'fs';
-import { resolve, join, parse } from 'path';
+import { parse, resolve, join } from 'path';
+import { glob } from 'glob';
 
 export function resolveEntryPath(
   entrypoint: string = 'dev',
   targetDir: string,
 ): string {
   const { dir: entryDir, name: entryName } = parse(entrypoint);
-  const entryPath = join(entryDir, entryName);
-  const parentPath = resolve(targetDir, entryDir);
-  const isFile = readdirSync(parentPath).some(base => {
-    const path = resolve(parentPath, base);
-    return statSync(path).isFile();
-  });
-  return isFile ? entryPath : join(entryPath, 'index');
+  const [entryFile] = glob.sync(`${resolve(targetDir, entryDir, entryName)}.*`);
+  if (entryFile) {
+    return join(entryDir, entryName);
+  }
+  return join(entryDir, entryName, 'index');
 }
 
 export async function startPackage(options: {