Stream functions hang if oauth config is invalid

[jlarigakis]

To reproduce

Without setting the environment variables $TWITTER_ACCESS_TOKEN etc, run iex -S mix and call
ExTwitter.stream_sample |> Enum.to_list
(Or set the environment variables to invalid values, or invalidate your credentials using the web interface, etc.)

Expected behaviour

The call fails immediately, logging or returning an auth error

Observed behaviour

The call does nothing for several seconds, then eventually times out without displaying an error.

[parroty]

Thanks for reporting the issue and sorry not being responsive. I've tried to fix the behavior as above.

incorrect authorization parameters

Interactive Elixir (1.5.0) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> ExTwitter.stream_sample |> Enum.take(3) |> Enum.to_list |> Enum.map(fn(x) -> x.text end)

22:44:23.663 [error] Error returned, stopping stream (Authorization Required).
[]

correct authorization parameters

Interactive Elixir (1.5.0) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> ExTwitter.stream_sample |> Enum.take(3) |> Enum.to_list |> Enum.map(fn(x) -> x.text end)
["RT @ChiyoFather: SideM 3rd Live 仙台 １日、２日目出演者公開 https://t.co/R6XYxJ3cPw",
 "RT @sidelust: Me talking to my family:\n\n▶ 🔘──────── 00:02\n\nMe talking to boys: \n\n▶ 🔘──────── 00:08\n\nMe talking to my dog:\n\n▶ 🔘──────── 1:54…",
 "RT @sateco: ハゲっていつの間に経営戦略研究科の客員教授になったのｗｗｗｗｗｗｗ"]