schnittchen
I’d like to get compiler warnings as errors in my tests, because in my experience, such warnings quite often uncover real bugs.
What I’ve tried before:
- alias configuration in
mix.exs, which exactly I forgot test_elixirc_options: [warnings_as_errors: true, docs: false, debug_info: false]inproject/0inmix.exs, which looks like the correct thing to do, but did not have the desired effect.
By desired effect I mean that not only I want such warnings to be shown, but to cause an exit with a non-zero exit status.
This looks highly relevant: elixir/lib/mix/lib/mix/tasks/test.ex at v1.17.0 · elixir-lang/elixir · GitHub
The documentation some lines above suggests
https://github.com/elixir-lang/elixir/blob/v1.17.0/lib/mix/lib/mix/tasks/test.ex#L210C11-L210C87
which does not work for me.
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Ankhers
Your link has a comment right before it that mentions that the
--warnings-as-errorsflag is not passed down to tests. If you want to do this you are going to need two different steps.Personally, I dislike using things like
--warnings-as-errorsin dev and test. There are times when I want to compile or test my code when it is in an unfinished state. Though, I always run--warnings-as-errorswithin CI when I try to get my changes merged into the base branch.rathorevk
Another way to set warnings as errors in tests, you can configure this in your
test_helper.exsby adding:check the official documentation: Code.put_compiler_option/2.