rebar.config.script

IsRebar3 = case application:get_key(rebar, vsn) of
               {ok, VSN} ->
                   [VSN1 | _] = string:tokens(VSN, "-"),
                   [Maj, Min, Patch] = string:tokens(VSN1, "."),
                   (list_to_integer(Maj) >= 3);
               undefined ->
                   false
           end,

Rebar2Deps0 = [{idna, ".*",
               {git, "https://github.com/benoitc/erlang-idna",
                {tag, "1.1.0"}}},

              {mimerl, ".*",
               {git, "https://github.com/benoitc/mimerl",
                {tag, "1.0.2"}}},

              {certifi, ".*",
               {git, "https://github.com/certifi/erlang-certifi",
                {tag, "0.4.0"}}},

              {metrics, ".*",
               {git, "https://github.com/benoitc/erlang-metrics",
                {tag, "1.0.1"}}},

              {ssl_verify_hostname, ".*",
               {git, "https://github.com/deadtrickster/ssl_verify_hostname.erl",
                {tag, "1.0.5"}}}],


Rebar2Deps = case os:getenv("TEST") of
                 "1" -> [{cowboy, ".*", {git, "https://github.com/ninenines/cowboy.git",
                                         {tag, "1.0.4"}}} | Rebar2Deps0];
                 false ->
                     Rebar2Deps0
             end,

case IsRebar3 of
    true ->
        CONFIG;
    false ->
        lists:keyreplace(deps, 1, CONFIG, {deps, Rebar2Deps})
end.