Add dialyxir to CI

[paulo-ferraz-oliveira]

This:

• adds dialyxir to CI (cached PLT)
• tweaks some code to get rid of compilation warnings
• solves all existing Dialyzer -issued warnings

I may add comments to my own changes to clarify intention or source, if applicable (though the individual commits should tell part of the story already - they will have comments).

[paulo-ferraz-oliveira]

Lemme know if you prefer a broader "no-line" entry.

[paulo-ferraz-oliveira]

Because nimble_parsec specific errors as String.t().

Another solution is to pull request there so the error reason can be term(), for example.

[paulo-ferraz-oliveira]

For lolspeed 😄

[benwilson512]

Nice, Thanks!

[benwilson512]

@paulo-ferraz-oliveira I ended up removing dialyxer from the CI in #1253 since it immediately had issues w/ PLT caches that I didn't understand. You're welcome to reintroduce it but some guidance about how to manage the caches when adding Elixir / OTP versions would be appreciated.

[paulo-ferraz-oliveira]

Caches usually should depend on whatever would invalidate them (in terms of key naming), as in

key: "${{ runner.os }}-erlang-${{ matrix.otp }}-elixir-${{ matrix.elixir }}-${{ hashFiles('mix.lock') }}"

(OS + OTP version + Elixir version + mix.lock hash)

What problems did you run into?

As for guidance, I think the above should be enough, but maybe you want something different (?)

[benwilson512]

You can see the job that failed here https://github.com/absinthe-graphql/absinthe/actions/runs/5408206586/jobs/9827039687

[paulo-ferraz-oliveira]

Edit: it's not cache -related, but Elixir 1.15 -related.

Oh, from the top of my head this might be because we recently released a new setup-beam version that changed where stuff was kept (1.16), so the cached elements fail because the cache is no longer found in the same place (OS-wise) and the PLT is static in references.

Would you be willing to delete the caches? I'd pull request again to re-introduce dialyxir in CI and you shouldn't see that problem (well, at least not until setup-beam breaks again 😢).

Check erlef/setup-beam#214 for some more history.

I just opened an issue for setup-beam (to discuss with maintainers) where this would potentially help avoid this class of issues.

[benwilson512]

Actually so if you look at this job here https://github.com/absinthe-graphql/absinthe/actions/runs/5423460943/jobs/9861420841 I added a cache key prefix and if you look at the cache action you can see it didn't find any PLT cache, but it still failed.

[paulo-ferraz-oliveira]

Yeah, I see that. Strange that it's complaining about a missing function: https://github.com/absinthe-graphql/absinthe/actions/runs/5423460943/jobs/9861420841#step:10:18.

The function is valid, though, as per https://www.erlang.org/doc/man/prettypr.html#text-1, but maybe it's not added to the analysis scope for dialyxir?

Lemme try to look at this closer. I need to fork, pull your branch, and make it fail before I can figure out what needs fixing :)

[paulo-ferraz-oliveira]

Yeah, so I also got it failing here: https://github.com/paulo-ferraz-oliveira/absinthe/actions/runs/5425961530/jobs/9867389890

Now on to figure stuff out 😄

Edit: will also be sure to use Erlang 25.3.2.3 and Elixir 1.15.1, locally, to make sure no issue is apparent from that distinction.

[paulo-ferraz-oliveira]

Not breaking using Elixir 1.14.5, but breaking using 1.15.1. IIrc, this is an intentional change for 1.15.x (lemme look that up).

Edit: also potentially related > jeremyjh/dialyxir#478

[paulo-ferraz-oliveira]

@benwilson512, I "fixed" it by doing:

   def application do
    [extra_applications: [:crypto, :logger | extra_extra_applications(Mix.env())]]
   end
 
  def extra_extra_applications(:test), do: [:syntax_tools]
  def extra_extra_applications(_), do: []

but this seems kinda hackish. I don't know what is including prettypr in this case, since in other Elixir lib.s I don't see the same issue.

[paulo-ferraz-oliveira]

A slightly less hackish (at least consistent with 1.15 release notes change) would be:

  def project do
    [
      ...
      prune_code_paths: prune_code_paths(Mix.env())
    ]
  end

  defp prune_code_paths(:test), do: false
  defp prune_code_paths(_), do: true

[paulo-ferraz-oliveira]

As per https://github.com/paulo-ferraz-oliveira/absinthe/actions/runs/5426289985/jobs/9868142420, from commit https://github.com/paulo-ferraz-oliveira/absinthe/commit/b6c39deef09d93103e84f4de4bb4b7b9cf6235ce, you can see that CI passes (your branch without further changes). If you find the test-specific option prune_code_paths set to false to have dialyxir pass (it's not only in CI, but locally too) I can add it. Otherwise we can wait for a dialyxir update that fixes it (?)

I'll open a pull request for that, and we can continue there.

[benwilson512]

Thanks for all of the work following up @paulo-ferraz-oliveira!