def test_search_hash(self):
h = create_table(5)
# Populate the table
insert_hash(10, h), insert_hash(11, h), insert_hash(12, h)
insert_hash(8, h), insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Check that each entry can be found
self.assertTrue(search_hash(10, h))
self.assertTrue(search_hash(11, h))
self.assertTrue(search_hash(109, h))
self.assertTrue(search_hash(12, h))
self.assertTrue(search_hash(8, h))
# Check that same-hash-different-value items can't be found
self.assertFalse(search_hash(100, h))
self.assertFalse(search_hash(21, h))
# Create a wrapping collision, make sure each can be found
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
self.assertTrue(search_hash(13, h))
self.assertTrue(search_hash(7, h))
def test_search_hash(self):
h = create_table(5)
# Populate the table
insert_hash(10, h), insert_hash(11, h), insert_hash(12, h)
insert_hash(8, h), insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Check that each entry can be found
self.assertTrue(search_hash(10, h))
self.assertTrue(search_hash(11, h))
self.assertTrue(search_hash(109, h))
self.assertTrue(search_hash(12, h))
self.assertTrue(search_hash(8, h))
# Check that same-hash-different-value items can't be found
self.assertFalse(search_hash(100, h))
self.assertFalse(search_hash(21, h))
# Create a wrapping collision, make sure each can be found
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
self.assertTrue(search_hash(13, h))
self.assertTrue(search_hash(7, h))
def test_remove_item(self):
h = create_table(5)
# Populate the table with starting values
insert_hash(10, h), insert_hash(11, h), insert_hash(12, h)
insert_hash(8, h), insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Remove item, make sure it can't be found
self.assertTrue(remove_item(10, h))
self.assertEqual(
h, ['USED', 11, 109, None, 12, 8, None, None, None, None])
self.assertFalse(search_hash(10, h))
# Remove collision-bumped items, make sure they can't be found
self.assertTrue(remove_item(109, h))
self.assertEqual(
h, ['USED', 11, 'USED', None, 12, 8, None, None, None, None])
self.assertFalse(search_hash(109, h))
self.assertTrue(remove_item(8, h))
self.assertEqual(
h, ['USED', 11, 'USED', None, 12, 'USED', None, None, None, None])
self.assertFalse(search_hash(8, h))
# Insert into a used slot, make sure item can be found
insert_hash(10, h)
self.assertEqual(
h, [10, 11, 'USED', None, 12, 'USED', None, None, None, None])
self.assertTrue(search_hash(10, h))
# Cause a collision which requires wrapping, remove collided item
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(h,
[10, 11, 13, None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(13, h))
self.assertEqual(
h, [10, 11, 'USED', None, 12, 'USED', None, None, None, 7])
# Check that the same item can't be added, and the one entry is successfully removed
insert_hash(11, h)
self.assertEqual(
h, [10, 11, 'USED', None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(11, h))
self.assertEqual(
h, [10, 'USED', 'USED', None, 12, 'USED', None, None, None, 7])
self.assertFalse(remove_item(11, h))
# Create a collision which requires wrapping, first remove sets hashed slot to used,
# locate collided item and remove it
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(
h, [10, 13, 'USED', None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(7, h))
self.assertEqual(
h, [10, 13, 'USED', None, 12, 'USED', None, None, None, 'USED'])
self.assertTrue(remove_item(13, h))
self.assertEqual(
h,
[10, 'USED', 'USED', None, 12, 'USED', None, None, None, 'USED'])
def test_insert_hash(self):
h = create_table(5)
# Check basic insertion works
insert_hash(10, h)
self.assertEqual(
h, [10, None, None, None, None, None, None, None, None, None])
insert_hash(11, h)
self.assertEqual(
h, [10, 11, None, None, None, None, None, None, None, None])
# Check that a collision moves to the next open slot
insert_hash(12, h) # needs slot 4
self.assertEqual(
h, [10, 11, None, None, 12, None, None, None, None, None])
insert_hash(8, h) # needs slot 4
self.assertEqual(h,
[10, 11, None, None, 12, 8, None, None, None, None])
insert_hash(109, h) # needs slot 1
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Check that a collision wraps around the list to first free slot
insert_hash(7, h) # needs slot 9
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, 7])
insert_hash(13, h) # also needs 9
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
# Check that duplicate entries don't do anything
insert_hash(13, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
def test_remove_item(self):
h = create_table(5)
# Populate the table with starting values
insert_hash(10, h), insert_hash(11, h), insert_hash(12, h)
insert_hash(8, h), insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Remove item, make sure it can't be found
self.assertTrue(remove_item(10, h))
self.assertEqual(h, ['USED', 11, 109, None, 12, 8, None, None, None, None])
self.assertFalse(search_hash(10, h))
# Remove collision-bumped items, make sure they can't be found
self.assertTrue(remove_item(109, h))
self.assertEqual(h, ['USED', 11, 'USED', None, 12, 8, None, None, None, None])
self.assertFalse(search_hash(109, h))
self.assertTrue(remove_item(8, h))
self.assertEqual(h, ['USED', 11, 'USED', None, 12, 'USED', None, None, None, None])
self.assertFalse(search_hash(8, h))
# Insert into a used slot, make sure item can be found
insert_hash(10, h)
self.assertEqual(h, [10, 11, 'USED', None, 12, 'USED', None, None, None, None])
self.assertTrue(search_hash(10, h))
# Cause a collision which requires wrapping, remove collided item
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(h, [10, 11, 13, None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(13, h))
self.assertEqual(h, [10, 11, 'USED', None, 12, 'USED', None, None, None, 7])
# Check that the same item can't be added, and the one entry is successfully removed
insert_hash(11, h)
self.assertEqual(h, [10, 11, 'USED', None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(11, h))
self.assertEqual(h, [10, 'USED', 'USED', None, 12, 'USED', None, None, None, 7])
self.assertFalse(remove_item(11, h))
# Create a collision which requires wrapping, first remove sets hashed slot to used,
# locate collided item and remove it
insert_hash(7, h), insert_hash(13, h)
self.assertEqual(h, [10, 13, 'USED', None, 12, 'USED', None, None, None, 7])
self.assertTrue(remove_item(7, h))
self.assertEqual(h, [10, 13, 'USED', None, 12, 'USED', None, None, None, 'USED'])
self.assertTrue(remove_item(13, h))
self.assertEqual(h, [10, 'USED', 'USED', None, 12, 'USED', None, None, None, 'USED'])
def test_insert_hash(self):
h = create_table(5)
# Check basic insertion works
insert_hash(10, h)
self.assertEqual(h, [10, None, None, None, None, None, None, None, None, None])
insert_hash(11, h)
self.assertEqual(h, [10, 11, None, None, None, None, None, None, None, None])
# Check that a collision moves to the next open slot
insert_hash(12, h) # needs slot 4
self.assertEqual(h, [10, 11, None, None, 12, None, None, None, None, None])
insert_hash(8, h) # needs slot 4
self.assertEqual(h, [10, 11, None, None, 12, 8, None, None, None, None])
insert_hash(109, h) # needs slot 1
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, None])
# Check that a collision wraps around the list to first free slot
insert_hash(7, h) # needs slot 9
self.assertEqual(h, [10, 11, 109, None, 12, 8, None, None, None, 7])
insert_hash(13, h) # also needs 9
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
# Check that duplicate entries don't do anything
insert_hash(13, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
insert_hash(109, h)
self.assertEqual(h, [10, 11, 109, 13, 12, 8, None, None, None, 7])
