How to use py.test tmpdir

py.test_tmpdir_usage

# https://pytest.org/latest/tmpdir.html
# http://py.readthedocs.org/en/latest/path.html

  
# Using in conftest.py
@pytest.fixture(autouse=True)
def a_tmp_filename(tmpdir):
  p = tmpdir.join("filename")
  p.write("some stuff\n")
  return str(p)  # str(p) returns the full pathname you can use with normal modules


def test_thing(tmpdir):
  tmp_file = tmpdir.join("thefile_name.json")
  tmp_file_name = str(tmp_file)
  with open(tmp_file_name, 'w') as f:
     json.dump(stuff, tmp_file)
     
  tmp_file.write(a_string_to_write)