'``ProcessNode.run`` runs a command that is a combination of the
initial arguments and the ones given to ``run()``.'

def test_run_runs_command(self):

    node = ProcessNode(initial_command_arguments=['sh'])
    temp_file = self.mktemp()
    with node.run(['-c', ('echo    hello    >    ' + temp_file)]):
        pass
    self.assertEqual(FilePath(temp_file).getContent(), 'hello\n')
