# test that we can run the garbage collector within threads
#
# MIT license; Copyright (c) 2016 Damien P. George on behalf of Pycom Ltd

import gc
import _thread


def thread_entry(n):
 # allocate a bytearray and fill it
 data = bytearray(i for i in range(256))

 # do some work and call gc.collect() a few times
 for i in range(n):
 for i in range(len(data)):
 data[i] = data[i]
 gc.collect()

 # print whether the data remains intact and indicate we are finished
 with lock:
 print(list(data) == list(range(256)))
 global n_finished
 n_finished += 1


lock = _thread.allocate_lock()
n_thread = 4
n_finished = 0

# spawn threads
for i in range(n_thread):
 _thread.start_new_thread(thread_entry, (10,))

# busy wait for threads to finish
while n_finished < n_thread:
 pass