def test_cursor(self):
k = Key("/")
self.assertRaises(ValueError, Cursor, None, None)
self.assertRaises(ValueError, Cursor, Query(Key("/")), None)
self.assertRaises(ValueError, Cursor, None, [1])
c = Cursor(Query(k), [1, 2, 3, 4, 5]) # should not raise
self.assertEqual(c.skipped, 0)
self.assertEqual(c.returned, 0)
self.assertEqual(c._iterable, [1, 2, 3, 4, 5])
c.skipped = 1
c.returned = 2
self.assertEqual(c.skipped, 1)
self.assertEqual(c.returned, 2)
c._skipped_inc(None)
c._skipped_inc(None)
self.assertEqual(c.skipped, 3)
c._returned_inc(None)
c._returned_inc(None)
c._returned_inc(None)
self.assertEqual(c.returned, 5)
self.subtest_cursor(Query(k), [5, 4, 3, 2, 1], [5, 4, 3, 2, 1])
self.subtest_cursor(Query(k, limit=3), [5, 4, 3, 2, 1], [5, 4, 3])
self.subtest_cursor(Query(k, limit=0), [5, 4, 3, 2, 1], [])
self.subtest_cursor(Query(k, offset=2), [5, 4, 3, 2, 1], [3, 2, 1])
self.subtest_cursor(Query(k, offset=5), [5, 4, 3, 2, 1], [])
self.subtest_cursor(Query(k, limit=2, offset=2), [5, 4, 3, 2, 1], [3, 2])
v1, v2, v3 = version_objects()
vs = [v1, v2, v3]
t1 = v1["committed"]
t2 = v2["committed"]
t3 = v3["committed"]
self.subtest_cursor(Query(k), vs, vs)
self.subtest_cursor(Query(k, limit=2), vs, [v1, v2])
self.subtest_cursor(Query(k, offset=1), vs, [v2, v3])
self.subtest_cursor(Query(k, offset=1, limit=1), vs, [v2])
self.subtest_cursor(Query(k).filter("committed", ">=", t2), vs, [v2, v3])
self.subtest_cursor(Query(k).filter("committed", "<=", t1), vs, [v1])
self.subtest_cursor(Query(k).order("+committed"), vs, [v1, v2, v3])
self.subtest_cursor(Query(k).order("-created"), vs, [v3, v2, v1])
def subtest_cursor(self, query, iterable, expected_results):
self.assertRaises(ValueError, Cursor, None, None)
self.assertRaises(ValueError, Cursor, query, None)
self.assertRaises(ValueError, Cursor, None, iterable)
cursor = Cursor(query, iterable)
self.assertEqual(cursor.skipped, 0)
self.assertEqual(cursor.returned, 0)
cursor._ensure_modification_is_safe()
cursor.apply_filter()
cursor.apply_order()
cursor.apply_offset()
cursor.apply_limit()
cursor_results = []
for i in cursor:
self.assertRaises(AssertionError, cursor._ensure_modification_is_safe)
self.assertRaises(AssertionError, cursor.apply_filter)
self.assertRaises(AssertionError, cursor.apply_order)
self.assertRaises(AssertionError, cursor.apply_offset)
self.assertRaises(AssertionError, cursor.apply_limit)
cursor_results.append(i)
# ensure iteration happens only once.
self.assertRaises(RuntimeError, iter, cursor)
self.assertEqual(cursor_results, expected_results)
self.assertEqual(cursor.returned, len(expected_results))
self.assertEqual(cursor.skipped, query.offset)
if query.limit:
self.assertTrue(cursor.returned <= query.limit)
