| James Kuszmaul | 05ccb27 | 2023-07-13 10:58:14 -0700 | [diff] [blame^] | 1 | #include <set> |
| 2 | #include <unordered_set> |
| 3 | |
| 4 | #include "glog/logging.h" |
| 5 | #include "gtest/gtest.h" |
| 6 | |
| 7 | #include "aos/uuid.h" |
| 8 | |
| 9 | namespace aos { |
| 10 | namespace testing { |
| 11 | |
| 12 | // Tests that modest numbers of UUID::Random() calls cannot create UUID |
| 13 | // collisions (to test that we have not *completely* messed up the random number |
| 14 | // generation). |
| 15 | TEST(UUIDTest, CollisionTest) { |
| 16 | std::set<UUID> uuids; |
| 17 | // When we only had ~32 bits of randomness in our UUIDs, we could generate |
| 18 | // issues with only ~sqrt(2 ** 32) (aka 2 ** 16) UUIDs. |
| 19 | // Just go up to 2 ** 22, since too much longer just makes this test take |
| 20 | // obnoxiously long. |
| 21 | for (size_t ii = 0; ii < (1UL << 22); ++ii) { |
| 22 | UUID uuid = UUID::Random(); |
| 23 | ASSERT_FALSE(uuids.count(uuid) > 0) << ii; |
| 24 | uuids.insert(uuid); |
| 25 | } |
| 26 | } |
| 27 | } // namespace testing |
| 28 | } // namespace aos |