test_queues.py

import unittest

from algorithms.queues import (
    ArrayQueue, LinkedListQueue,
    max_sliding_window,
    reconstruct_queue,
    PriorityQueue
)


class TestQueue(unittest.TestCase):
    """
        Test suite for the Queue data structures.
    """

    def test_ArrayQueue(self):
        queue = ArrayQueue()
        queue.enqueue(1)
        queue.enqueue(2)
        queue.enqueue(3)

        # test __iter__()
        it = iter(queue)
        self.assertEqual(1, next(it))
        self.assertEqual(2, next(it))
        self.assertEqual(3, next(it))
        self.assertRaises(StopIteration, next, it)

        # test __len__()
        self.assertEqual(3, len(queue))

        # test is_empty()
        self.assertFalse(queue.is_empty())

        # test peek()
        self.assertEqual(1, queue.peek())

        # test dequeue()
        self.assertEqual(1, queue.dequeue())
        self.assertEqual(2, queue.dequeue())
        self.assertEqual(3, queue.dequeue())

        self.assertTrue(queue.is_empty())

    def test_LinkedListQueue(self):
        queue = LinkedListQueue()
        queue.enqueue(1)
        queue.enqueue(2)
        queue.enqueue(3)

        # test __iter__()
        it = iter(queue)
        self.assertEqual(1, next(it))
        self.assertEqual(2, next(it))
        self.assertEqual(3, next(it))
        self.assertRaises(StopIteration, next, it)

        # test __len__()
        self.assertEqual(3, len(queue))

        # test is_empty()
        self.assertFalse(queue.is_empty())

        # test peek()
        self.assertEqual(1, queue.peek())

        # test dequeue()
        self.assertEqual(1, queue.dequeue())
        self.assertEqual(2, queue.dequeue())
        self.assertEqual(3, queue.dequeue())

        self.assertTrue(queue.is_empty())


class TestSuite(unittest.TestCase):
    def test_max_sliding_window(self):
        array = [1, 3, -1, -3, 5, 3, 6, 7]
        self.assertEqual(max_sliding_window(array, k=5), [5, 5, 6, 7])
        self.assertEqual(max_sliding_window(array, k=3), [3, 3, 5, 5, 6, 7])
        self.assertEqual(max_sliding_window(array, k=7), [6, 7])

        array = [8, 5, 10, 7, 9, 4, 15, 12, 90, 13]
        self.assertEqual(max_sliding_window(array, k=4),
                         [10, 10, 10, 15, 15, 90, 90])
        self.assertEqual(max_sliding_window(array, k=7), [15, 15, 90, 90])
        self.assertEqual(max_sliding_window(array, k=2),
                         [8, 10, 10, 9, 9, 15, 15, 90, 90])

    def test_reconstruct_queue(self):
        self.assertEqual([[5, 0], [7, 0], [5, 2], [6, 1], [4, 4], [7, 1]],
                         reconstruct_queue([[7, 0], [4, 4], [7, 1], [5, 0],
                                           [6, 1], [5, 2]]))


class TestPriorityQueue(unittest.TestCase):
    """Test suite for the PriorityQueue data structures.
    """

    def test_PriorityQueue(self):
        queue = PriorityQueue([3, 4, 1, 6])
        self.assertEqual(4, queue.size())
        self.assertEqual(1, queue.pop())
        self.assertEqual(3, queue.size())
        queue.push(2)
        self.assertEqual(4, queue.size())
        self.assertEqual(2, queue.pop())


if __name__ == "__main__":
    unittest.main()