Elixir: .formatter.exs `import_deps` does not work for git dependencies

[ejpcmac]

Environment

• Elixir & Erlang versions (elixir --version):

  Erlang/OTP 20 [erts-9.2] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:10] [hipe] [kernel-poll:false]                    
  Elixir 1.6.1 (compiled with OTP 20)
  

• Operating system: Linux (Fedora 26)

Current behavior

When I try to run mix format with an import_deps containing a Git dependency, it fails:

** (Mix) Unknown dependency :mock_uart given to :import_deps in the formatter configuration. The dependency is not listed in your mix.exs file

In my mix.exs, I have:

{:mock_uart, git: "http://<some_internal_address>/mock_uart.git", tag: "v0.1.0", only: :test}

Expected behavior

mix format should work as with Hex dependencies.

[josevalim]

Just too double check. Does it also happen after you run mix deps.get?

[ejpcmac]

Just too double check. Does it also happen after you run mix deps.get?

Yes, I’ve even run mix deps.clean --all, then mix deps.get to be sure.

[wojtekmach]

I wasn't able to reproduce this on Elixir master with {:ecto, github: "elixir-ecto/ecto"}.

I think the problem is that your dependency has only: :test which means it's not available in the default :dev environment which is used when doing mix format. I think if you change the dep to be only: [:dev, :test] it should work.

[josevalim]

Good catch @wojtekmach. I will include the environment in the error message.