Make ExUnit test pass when process fails to start

[peerreynders]

Anything wrong with the terminate_wait approach?

Testing {:stop, :some_error} in Genserver.init/1 with ExUnit

I’ve used Process.flag(:trap_exit, true) (Process.flag/2) in the past inside the test module - just make sure to purge the resulting :EXIT message from the test process mailbox. Looking at catch_exit/1 it seems to be designed to catch an exit inside the same process that triggered it with Kernel.exit/1 Example: see test "FrequencySup demo" defmodule FrequencySupTest do use ExUnit.Case setup do {:ok, sup} = FrequencySup.start_link() on_exit fn -> refute (Process.alive? sup)…

So for example you could just stick a monitor on the process and wait for the :DOWN message with a blocking receive with a timeout.