Ubiquity Black Box Testing Problem Set

gistfile1.py

# CORRECT SPECIFICATION:
#
# the Queue class provides a fixed-size FIFO queue of integers
#
# the constructor takes a single parameter: an integer > 0 that
# is the maximum number of elements the queue can hold.
#
# empty() returns True if and only if the queue currently
# holds no elements, and False otherwise.
#
# full() returns True if and only if the queue cannot hold
# any more elements, and False otherwise.
#
# enqueue(i) attempts to put the integer i into the queue; it returns
# True if successful and False if the queue is full.
#
# dequeue() removes an integer from the queue and returns it,
# or else returns None if the queue is empty.
#
# Example:
# q = Queue(1)
# is_empty = q.empty()
# succeeded = q.enqueue(10)
# is_full = q.full()
# value = q.dequeue()
#
# 1. Should create a Queue q that can only hold 1 element
# 2. Should then check whether q is empty, which should return True
# 3. Should attempt to put 10 into the queue, and return True
# 4. Should check whether q is now full, which should return True
# 5. Should attempt to dequeue and put the result into value, which
#    should be 10
#
# Your test function should run assertion checks and throw an
# AssertionError for each of the 5 incorrect Queues. Pressing
# submit will tell you how many you successfully catch so far.

from queue_test import *

def test():
    q = Queue(1)
    assert not q.full()
    x = q.dequeue()
    assert x == None

    q.enqueue(-1)
    x = q.dequeue()
    assert x == -1

    size = 9999
    q = Queue(size)
    data = range(size)
    for d in data:
        success = q.enqueue(d)
        assert success

    for d in data:
        if d < (size-1):
            is_empty = q.empty()
            assert not is_empty
        q.dequeue()