** (Mariaex.Error) (1064): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'NULL' at line 1
    (ecto) lib/ecto/adapters/sql.ex:185: Ecto.Adapters.SQL.query!/5
    (ecto) lib/ecto/adapters/mysql.ex:85: anonymous fn/4 in Ecto.Adapters.MySQL.execute_ddl/3
    (elixir) lib/enum.ex:1473: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto) lib/ecto/adapters/mysql.ex:85: Ecto.Adapters.MySQL.execute_ddl/3
    (ecto) lib/ecto/migration/runner.ex:89: anonymous fn/2 in Ecto.Migration.Runner.flush/0
    (elixir) lib/enum.ex:1473: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto) lib/ecto/migration/runner.ex:87: Ecto.Migration.Runner.flush/0
    (stdlib) timer.erl:181: :timer.tc/

I’m getting this error when running mix test. It’s a Phoenix application.

I’ve tried a lot of things. Deleting all tests, old branches, commenting certain sections, deleting the git repo and downloading again, upgrading mysql, removing mysql and installing again, upgrading some deps.

In my colleague’s laptop this runs fine and we’ve got the exact same setup (Ubuntu, same MYSQL version, same erlang and elixir version). This was working fine some time ago, but now it breaks with this error.

We’re at a loss on how to solve this It seems to come from a bad query in Ecto that’s using something from timer.erl (maybe something related to processes sleeping?