It is not the umbrella app which causes the problem (successfully using MecksUnit with an umbrella app myself).
A new version has been released. Tackling the error when trying to unload a non-mocked module. Your problem should be solved with MecksUnit v0.1.6. Please confirm, ok?
Now I’m not sure what’s going on. The error goes away, but I either get the error or not depending on test seed.
mix test --seed 57991 test/merchant_web/
...
Finished in 8.1 seconds
2 doctests, 92 tests, 0 failures
mix test --seed 398178 test/merchant_web/
1) test POST /merchant/register creates Company, User (owner), Permission and CompanyCurrency (MerchantWeb.UserControllerTest)
test/merchant_web/controllers/user_controller_test.exs:134
** (CaseClauseError) no case clause matching: []
code: |> post("/merchant/register", params)
stacktrace:
(hackney) /home/sztosz/Documents/Bitt/mmoney-umbrella/deps/hackney/src/hackney_url.erl:211: :hackney_url.parse_netloc/2
(hackney) /home/sztosz/Documents/Bitt/mmoney-umbrella/deps/hackney/src/hackney.erl:345: :hackney.request/5
(httpoison) lib/httpoison/base.ex:630: HTTPoison.Base.request/9
(ledger_service) lib/ledger_service.ex:131: LedgerService.init/2
Finished in 8.1 seconds
2 doctests, 92 tests, 1 failure
I omitted the stack trace, because it’s irrelevant, but honestly I have no clue why with some seeds the mocked module is used in test, and why with other seeds test uses original module.
OK, i don’t know what was the real issue, I changed code so many times, I changed between versions of MecksUnit, I changed between MecksUnit and Mock many times. After last change of failing test from Mock to MecksUnit it started to work. Just like that.
So what I wanted to write is, thank you for your changes, after all it works Like I need it to work, and what’s most important… It works 
UPDATE: Actually random seeds still make tests fail (those using the mocks) and other don’t. ¯_(ツ)_/¯
You are welcome (for what it’s worth).
Can you please try to reproduce it in such a way that I have a case which I need to solve? I can imagine that you sharing your code is not what you want. So a smaller (non-valuable) case would be better.
Really hoping that you can deliver such a small case
I moved to Mox after being unable to find the issue. If I find time next week I’ll try to create something to that will reproduce this strange behaviour. But really don’t know what can be the cause. And I can’t share the original code.
Hi! This looks really interesting.
By that you mean that I can/need to define multiple times the mocked module based on the mocked_test?
Can I define mocks inside describe blocks?
Thanks for your contribution!!!
I’m not sure, but this may have been what caused my tests to fail. 
Because I had many test files with many tests in them each, and few of those files were mocking same function from the same module.
The amount of files mocking the same function should not be a problem (MecksUnit makes it one mocked function). Maybe you could provide a pseudo test file with a similar structure in terms of tests, setup, etc.
Haven’t tried that yet to be honest. But my guess is that the defined module within the describe block still only counts for the first mocked_test that is encountered.
How would you like it to behave? Can you give a pseudo code example?
