def METHOD_NAME(self):
    """2to3 a single file with a new output dir."""
    self.setup_test_source_trees()
    err = StringIO.StringIO()
    ret = self.run_2to3_capture(
            ["-n", "-w", "--no-diffs", "--output-dir", self.py3_dest_dir,
             self.trivial_py2_file],
            StringIO.StringIO(""), StringIO.StringIO(), err)
    self.assertEqual(ret, 0)
    stderr = err.getvalue()
    self.assertIn(
            "Output in %r will mirror the input directory %r layout" % (
                    self.py3_dest_dir, self.py2_src_dir), stderr)
    self.assertEqual(set([os.path.basename(self.trivial_py2_file)]),
                     set(os.listdir(self.py3_dest_dir)))