text: import sys, os
  import py
  from pypy.tool.nullpath import NullPyPathLocal
  
  def test_nullpath(tmpdir):
      path = NullPyPathLocal(tmpdir)
      assert repr(path).endswith('[fake]')
      foo_txt = path.join('foo.txt')
      assert isinstance(foo_txt, NullPyPathLocal)
      #
      f = foo_txt.open('w')
      assert f.name == os.devnull
  