import os

import pytest

import parsl
from parsl.app.app import python_app
from parsl.tests.configs.local_threads import config


def local_setup():
    global dfk
    dfk = parsl.load(config)


def local_teardown():
    parsl.clear()


@python_app
def slow_double(x, sleep_dur=1, cache=True):
    import time
    time.sleep(sleep_dur)
    return x * 2


@pytest.mark.local
def test_checkpointing():
    """Testing code snippet from documentation
    """

    N = 5  # Number of calls to slow_double
    d = []  # List to store the futures
    for i in range(0, N):
        d.append(slow_double(i))

    # Wait for the results
    [i.result() for i in d]

    checkpoint_dir = dfk.checkpoint()
    print(checkpoint_dir)

    assert os.path.exists(checkpoint_dir), "Checkpoint dir does not exist"
