[Bug]: v7 regression in a monorepo since prerelease

[xalechez]

What version of React Router are you using?

7.0.1

Steps to Reproduce

• Create a repository with a package.json in a root
• Install react router 7 dependencies to the package.json above
• Create a directory like apps/test-app with vite.config.ts and react-router.config.ts specifying appDirectory
• Run react-router build -c apps/test-app/vite.config.ts from the root of the repository

RR7 config:

import { join } from 'node:path';

import { build } from 'esbuild';

import type { Config } from '@react-router/dev/config';

export default {
  appDirectory: join(import.meta.dirname, 'app'),
  buildDirectory: join(
    import.meta.dirname,
    '../../dist/apps/test-app/static',
  ),
  serverModuleFormat: 'esm',
  ssr: true,
  buildEnd: async () => {
    await build({
      outfile: join(import.meta.dirname, '../../dist/apps/test-app/rr7.mjs'),
      entryPoints: [join(import.meta.dirname, 'rr7.mts')],
      external: [
        join(
          import.meta.dirname,
          '../../dist/apps/test-app/static/server/index.js',
        ),
      ],
      platform: 'node',
      format: 'esm',
      packages: 'external',
      bundle: true,
      logLevel: 'info',
    }).catch((error: unknown) => {
      console.error('Error building server:', error);
      process.exit(1);
    });
  },
} satisfies Config;

Expected Behavior

I would like to be able to run my application from the root of my monorepo by specifying the location of vite.config.ts like I did when I tested a pre-release version

OR

I would like to be able to run my application from apps/test-app with the package.json resolved from the root of my monorepo

Actual Behavior

Currently it works in two modes:

• Either I run a script from the root and react-router fails with Error: Could not find a root route module in the app directory as "app/root.tsx"
• Or I run it from the app folder and it fails to resolve package.json

This problem can be solved just by adding a package.json to the app folder, but we opted in to single version policy per monorepo as it becomes quite tedious to maintain dependencies for multiple applications at the same time. React Router 7 pre-release satisfied our needs, but as vite config and RR config are now separated, it looks like this functionality is no longer supported