Erlang Typespec issue

[isaacsanders]

Environment

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

 $ asdf current
elixir         1.10.2
erlang         22.2.1

• Which version of Dialyxir are you using? (cat mix.lock | grep dialyxir):

 $ cat mix.lock | grep dia
  "dialyxir": {:hex, :dialyxir, "1.0.0", "6a1fa629f7881a9f5aaf3a78f094b2a51a0357c843871b8bc98824e7342d00a5", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "aeb06588145fac14ca08d8061a142d52753dbc2cf7f0d00fc1013f53f8654654"},

Current behavior

lib/sftp_client.ex:34:call
The function call will not succeed.

:ssh_sftp.read_file(_pid :: any(), <<_::8, _::size(1)>>)

will never return since the success typing is:
(pid(), string()) :: {:error, atom() | string() | tuple()} | {:ok, binary()}

and the contract is
(channelPid, file) :: {:ok, :Data} | :Error
when channelPid: pid(), file: string(), data: binary(), error: {:error, reason()}

________________________________________________________________________________
done (warnings were emitted)

Expected behavior

This should succeed according to the typespec in erlang documentation.

[jeremyjh]

Dialyzer returning a warning you think is wrong is not going to be a bug in Dialyxir, since we only integrate Dialyzer into Mix. Dialyzer still does the analysis. My advice for this kind of thing is to ask on the elixirforums.com, you will need to supply a code example that can reproduce the problem. 99.99% of the time, the problem is in your code, your typespec or a dependency's typespec.

[jeremyjh]

This is just a warning, and based on the output it does look like the success typing doesn't match the contract. Without seeing your code I couldn't begin to guess.