Getting undefined function error - but it is present

Thanks! setup_all did the trick … it needed code as indicated below:

  setup_all do
    # Explicitly get a connection before each test
    # By default the test is wrapped in a transaction
    :ok = Ecto.Adapters.SQL.Sandbox.checkout(Koko.Repo)

    # The :shared mode allows a process to share
    # its connection with any other process automatically
    Ecto.Adapters.SQL.Sandbox.mode(Koko.Repo, { :shared, self() })

    :ok
  end