I have a library that uses Ecto and Postgrex (Postgrex is only used in tests).
After upgrading from Ecto 1 to Ecto 2, the test suite started giving this error:
$ mix test
Compiling 4 files (.ex)
Generated ectoo app
** (EXIT from #PID<0.46.0>) shutdown: failed to start child: DBConnection.Ownership.Manager
** (EXIT) exited in: GenServer.call(DBConnection.Ownership.PoolSupervisor, {:start_child, [#PID<0.175.0>, Postgrex.Protocol, [pool: DBConnection.Poolboy, types: true, hostname: "localhost", types: true, otp_app: :ectoo, repo: Ectoo.Repo, adapter: Ecto.Adapters.Postgres, database: "ectoo_test", username: "henrik", pool_timeout: 5000, timeout: 15000, adapter: Ecto.Adapters.Postgres, database: "ectoo_test", username: "henrik", extensions: [{Ecto.Adapters.Postgres.DateTime, []}, {Postgrex.Extensions.JSON, [library: nil]}], port: 5432]]}, :infinity)
** (EXIT) no process
Any ideas?