/** packages/compiler-sfc/src/script/resolveType.ts */
/** line: 950 */

function resolveExt(filename: string, fs: FS) {
  // #8339 ts may import .js but we should resolve to corresponding ts or d.ts
  filename = filename.replace(/\.js$/, '')
  const tryResolve = (filename: string) => {
    if (fs.fileExists(filename)) return filename
  }
  return (
    tryResolve(filename) ||
    tryResolve(filename + `.ts`) ||
    tryResolve(filename + `.d.ts`) ||
    tryResolve(joinPaths(filename, `index.ts`)) ||
    tryResolve(joinPaths(filename, `index.d.ts`))
  )
}