EUnit examples: Using 'foreach'

31 Mar 2023 08:30 erlang eunit

We saw that setup runs setup/cleanup before all tests in a list. If you want to run some setup/cleanup before each test in a list, you can use foreach:

simple_foreach_test_() ->
    % 'foreach' sets up a fixture for each of the specified tests.
    {foreach, fun setup/0, fun cleanup/1, [
        fun something/0,
        fun another_thing/0

setup() ->
    {ok, Pid} = some_server:start_link(),

cleanup(Pid) ->
    % The result from setup is passed as the argument to cleanup.
    unlink(Pid),    % we don't also get killed
    exit(Pid, kill),

something() -> ?assert(true).
another_thing() -> ?assert(true).

If you’re coming from JUnit or similar, these are before_each and after_each.