import py
import sys

queue = py.std.Queue.Queue()

def test_gateway():
    for i in range(10):
        yield assert_receiver_callback_is_safe

def receiver_callback(data):
    #py.std.time.sleep(0.1)
    queue.put(data)

def assert_receiver_callback_is_safe():
    gw = py.execnet.PopenGateway()
    channel = gw.newchannel(receiver = queue.put)
    gw.remote_exec(channel = channel, source ='''
    import py
    num = channel.receive()
    for i in range(num):
        channel.send(i)
        #py.std.time.sleep(0.2)
    ''')
    number = 100
    channel.send(number)
    wait_finish(channel)
    assert channel.isclosed()
    received = []
    while not queue.empty():
        received.append(queue.get(False))
    assert received == range(number)
    del channel
    del gw
        
def wait_finish(channel):
   try:
       while 1:
           try:
               channel.waitclose(0.1)
           except (IOError, py.error.Error):
               continue
           else:
               return
   finally:
       try:
           channel.gateway.exit()
       except EOFError:
           # the gateway receiver callback will get woken up
           # and see an EOFError exception
           pass
       del channel