def test_simple():
  assert 1 + 1 == 2


def test_envionment():
  $USER = 'snail'
  x = 'USER'
  assert x in ${...}
  assert ${'U' + 'SER'} == 'snail'


def test_xonsh_party():
  x = 'xonsh'
  y = 'party'
  out = $(echo @(x + ' ' + y))
  assert out == 'xonsh party\n'