esbuild with router-plugin can't generate routeTree

[birkskyum]

Which project does this relate to?

Router

Describe the bug

When using esbuild with file-based routing, the routeTree isn't generated.

Your Example Website or App

https://stackblitz.com/edit/github-yqs94yab?file=src%2FrouteTree.gen.ts

Steps to Reproduce the Bug or Issue

Go to

• /e2e/react-router/basic-esbuild-file-based/

Delete

• ./src/routeTree.gen.ts

Run pnpm run build

Crash

> esbuild src/main.tsx --bundle --outfile=dist/main.js && tsc --noEmit

✘ [ERROR] Could not resolve "./routeTree.gen"

    src/main.tsx:4:26:
      4 │ import { routeTree } from './routeTree.gen'
        ╵                           ~~~~~~~~~~~~~~~~~

1 error
 ELIFECYCLE  Command failed with exit code 1.

Expected behavior

Regeneration of the routeTree

Screenshots or Videos

No response

Platform

• OS: macOS
• Browser: Chrome
• Version: 130.0.6723.58

Additional context

No response

[SeanCassiere]

From what I can tell so far, it looks to be that the router-plugin isn't being registered by esbuild.
In fact, I'm having doubts as to whether it's even detecting the esbuild.config.js file.