threadleak

#!/usr/bin/env python2
from __future__ import print_function
import gc
import time
import threading
from more_executors import Executors


def dump_threads():
    print("------------- threads ----------------")
    for thread in threading.enumerate():
        print("  {name} daemon={daemon} alive={alive}".format(
            name=thread.name, daemon=thread.daemon, alive=thread.is_alive()))
    print("")


def run_and_discard(exc):
    futures = []
    for _ in range(0, 10):
        futures.append(exc.submit(lambda: 42))
    print("Created %s futures" % len(futures))


def run_test(exc, shutdown=False):
    if shutdown:
        with exc() as executor:
            run_and_discard(executor)
            time.sleep(1)
    else:
        run_and_discard(exc())

    # Now we don't hold any references to either the executor or
    # any of its futures.
    # What happens?
    for i in range(0, 3):
        dump_threads()
        print("About to GC %s" % i)
        gc.collect()
        print("After GC %s" % i)
        time.sleep(5)


print("============== thread pool ======================")
run_test(lambda: Executors.thread_pool(max_workers=4))

print("============== thread pool w/retry w/shutdown ==============")
run_test(lambda: Executors.thread_pool(max_workers=4).with_retry(), shutdown=True)

print("============== thread pool w/retry ==============")
run_test(lambda: Executors.thread_pool(max_workers=4).with_retry())