Tests must be run sequentially

[joshuata]

Currently the tests will fail if run using the standard npm test command as it runs them in parallel. Each test suite uses the same database, so they write over each other constantly causing transient failures.

An ideal solution would be an adapter to jest that would allow you to run a test within a database transaction; start it before running the test function, and cancel it at the end. This would guarantee that tests do not mess with each other's state.

[joshuata]

Here's an example in mocha - the idea is similar:
sequelize/sequelize#11408 (comment)