'``ProcessNode.run()`` context manager returns the subprocess\' stdin.'

def test_run_stdin(self):

    node = ProcessNode(initial_command_arguments=['sh', '-c'])
    temp_file = self.mktemp()
    with node.run([('cat    >    ' + temp_file)]) as stdin:
        stdin.write('hello    ')
        stdin.write('world')
    self.assertEqual(FilePath(temp_file).getContent(), 'hello    world')
