build: tsdown vendor alias uses URL.pathname, which breaks pnpm build on Windows #3353

Problem

pnpm build fails on a Windows host:

Could not resolve '@limrun/xdelta3-wasm' ... Matched alias not found

tsdown.config.ts builds the vendor-alias target with new URL(..., import.meta.url).pathname, which yields a POSIX-shaped path on Windows:

'@limrun/xdelta3-wasm': new URL('./src/vendor/limrun-delta-sync-omitted.ts', import.meta.url)
  .pathname,

For file:///C:/.../src/vendor/limrun-delta-sync-omitted.ts, .pathname returns /C:/.../src/vendor/limrun-delta-sync-omitted.ts — a path with a leading slash before the drive letter, which no resolver can match.

Scope

Build-time only, for someone building from source on Windows. It does not affect running a published package, since releases are built on the Linux lanes.

Pre-existing, not introduced by any currently open PR. Present on main and on a7821ef58 (fix/windows-daemon-start-3291), whose diff does not touch tsdown.config.ts. Last change to the file: 0c1ebb33a, feat(provider-webdriver): add TestMu AI device cloud provider (#3118).

Fix

Use fileURLToPath from node:url:

import { fileURLToPath } from 'node:url';

'@limrun/xdelta3-wasm': fileURLToPath(new URL('./src/vendor/limrun-delta-sync-omitted.ts', import.meta.url)),

The reporter confirmed the build completes with that change, and ran the full native Windows checklist on top of it.

Found by

pai-scaffolde while building this head natively on Windows 11 — evidence at #3330 (comment). They offered to open a PR for it.