Comment by deepsun
14 days ago
Normal code has 50% to 90% ratio of code coverage by unit-tests. Dynamic-typed languages (Python, Ruby) usually require more, like 100% - 120%.
SQLite has 59,000% ratio [1]
Yet it didn't help for a bug to left unnoticed for 16 years :( I don't know what we can do for the industry. I doubt one can formally verify a project like SQLite, and keep it maintainable.
One might be able to formally verify the sqlite pager layer, where this problem occurred. It's just writing pages to disk and reading pages from disk, and providing ACID guarantees.