Wallaby with headless Chrome crashes

Question

I am developing an application based on Elixir and Phoenix which also uses the Wallaby application for HTTP based testing in a headless Chrome browser.

Now recently I receive a rather unwieldy error message when executing my ExUnit tests:

** (MatchError) no match of right hand side value:
    {:error, {:wallaby, {:bad_return, 
      {{Wallaby, :start, [:normal, []]},
      {:EXIT,
        {%Protocol.UndefinedError{description: "", protocol: Enumerable, value: nil},
        [{Enumerable, :impl_for!, 1, [file: '/root/deb/elixir_1.8.0-1/lib/elixir/lib/enum.ex', line: 1]},
         {Enumerable, :slice, 1, [file: '/root/deb/elixir_1.8.0-1/lib/elixir/lib/enum.ex', line: 193]},
         {Enum, :backwards_compatible_slice, 1, [file: 'lib/enum.ex', line: 2871]},
         {Enum, :slice_any, 3, [file: 'lib/enum.ex', line: 3075]},
         {Enum, :at, 3, [file: 'lib/enum.ex', line: 381]},
         {Wallaby.Experimental.Chrome, :validate, 0, [file: 'lib/wallaby/experimental/chrome.ex', line: 36]},
         {Wallaby, :start, 2, [file: 'lib/wallaby.ex', line: 27]},
         {:application_master, :start_it_old, 4, [file: 'application_master.erl', line: 277]}]}}}}}}

test/test_helper.exs:4: (file)
(elixir) lib/code.ex:767: Code.require_file/2
(elixir) lib/enum.ex:769: Enum."-each/2-lists^foreach/1-0-"/2
(elixir) lib/enum.ex:769: Enum.each/2

I am running a Debian GNU/Linux 9 "Stretch" and installed Elixir as a .deb package with version 1.8.0-1 from binaries.erlang-solutions.com . Wallaby is locked to {:wallaby, "~> 0.21.0"} .

Ideas on how to fix this would be greatly appreciated.

Answer 1

The problem is caused by Wallaby 0.21.0 not being able to handle a ChromeDriver version higher than 2.x, but ChromeDriver versions as high as 71.x are already around.

This has been fixed by this pull request , which has been merged into Wallaby master but doesn't seem to be released yet.