Dialyzer fails to validate the following code, which I believe to be correct usage of aws-elixir.

  def get_object(client, bucket, key) do
    case AWS.S3.get_object(client, bucket, key) do
      {:ok, _, %{body: body, status_code: 200}} ->
        body

     error={:error, :timeout} ->
        Logger.error("Timeout GET for: #{bucket}:#{key}.")
        error
    end
  end

The error is

 lib/myapp/s3.ex:xxx:pattern_match
The pattern can never match the type.

Pattern:
{:error, :timeout}

Type:

  {:error, {:unexpected_response, _} | %{binary() => _}}
  | {:ok, %{binary() => _}, %{:body => _, :status_code => _, _ => _}}

If you trace the supported error types for this example, you'll find:

• :hackney:request/5 return spec includes {:error, term()}
• AWS.HTTPClient.request/5 return spec includes {:error, term()}
• AWS.Request.request_rest/9 and AWS.Client.request/6 do not define a type spec, but pass through {:error, _} from the HTTPClient
• AWS.S3.get_object/23 return spec does not allow for {:error, term()}. However, the last function call is to AWS.Request.request_rest/9, so there is a discrepancy here on allowable returns

I confirmed that adding {:error, term()} to the return spec on AWS.S3.get_object/23 fixes this dialyzer error, and I'm prepared to submit a proper PR to the codegen for this.

However, this is obviously not ideal since it counteracts the intention of the more prescriptive error response type specs. In other words, in dialyzer's eyes, allowing term() means t:get_object_errors/0 is irrelevant.

Looking for guidance on a proper way to fix the type discrepancy. Thanks!