Compilation error with ExVCR and Finch in 1.19

Questions / Help
,
1

Hi! Trying to upgrade our project to 1.19.3 and OTP 28.1. Having deleted deps and build dirs, reinstalling everything and running mix test, I get the following compilation error

== Compilation error in file test/test.exs ==
** (RuntimeError) Missing dependency: Finch
(exvcr 0.15.2) lib/exvcr/adapter/finch.ex:113: ExVCR.Adapter.Finch.module_name/0

Looking at the code for the ExVCR Finch adaptor, there is this:

if Code.ensure_loaded?(Finch) do
  defmodule ExVCR.Adapter.Finch do
    <truncated impl for brevity>  
  end
else
  defmodule ExVCR.Adapter.Finch do
    def module_name, do: raise("Missing dependency: Finch")
    def target_methods, do: raise("Missing dependency: Finch")
  end
end

So it seems that during compile time, Finch is not available at all (?) Running Code.ensure_loaded?(Finch) in the test before the above comes into play returns true. I have no idea how to go about this. Any suggestions?

2

If you are using the Finch adapter, like this:

use ExVCR.Mock, adapter: ExVCR.Adapter.Finch

you have to install finch as a dependency in your project, in mix.exs:

{:finch, "~> 0.18"}

I don’t think your problem is related to elixir/erlang upgrade

3

It is installed - I can see it in my deps folder. It is also being used by other libs. Lastly, it works fine in 1.18 OTP 27, and starts behaving as soon as I switch to 1.19.

4

I tried replicating here. I have the exact same error only if I remove Finch dependency, otherwise it works for me. Could you send a minimal example so I can replicate?

5

I can try replicating in a new project, but I assume it won’t give anything since you tried and didn’t get the same error. I’m more inclined to believe I have made some other mistake in my current project, or missed some detail while upgrading Elixir.

Let me get back to you

6

@phcurado I actually managed to reproduce it: GitHub - westmark/exvcr_finch_repro Running `mix test` gives me the error. If it doesn’t do the same for you it must be something with my environment.

7

great! I could replicate the error on your repository. I think the problem might be the exvcr version.
I managed to make it work by changing exvcr version:

{:exvcr, "~> 0.17", only: :test},

And running on the terminal:

mix deps.update exvcr

After this the tests work, maybe it have a bug on old versions of exvcr but I don’t know the cause.

8

Ah of course. I couldn’t test with the latest as I have a lot of issues with other downstream libs that conflict with each other and I had to make my own temporary version of them. I should have tested 0.17 in my repro.. :man_facepalming:

Thanks for helping me out!

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