Function findNearestPackagePath

packages/vite/src/node/plugins/resolve.ts:1190–1199

(
  file: string,
  legacyInconsistentCjsInterop: boolean | undefined,
  packageCache: PackageCache | undefined,
  isBuild: boolean,
)

}

function findNearestPackagePath(
  file: string,
  legacyInconsistentCjsInterop: boolean | undefined,
  packageCache: PackageCache | undefined,
  isBuild: boolean,
) {
  if (!isBuild || legacyInconsistentCjsInterop) return
  const pkgData = findNearestPackageData(file, packageCache)
  return pkgData ? path.join(pkgData.dir, 'package.json') : null
}