[RFC] Test rebar3 and recent OTP on CI

.travis.yml

@@ -3,6 +3,16 @@ notifications:
   webhooks: http://basho-engbot.herokuapp.com/travis?key=92c392ada1e45ef632b5df7cf7104e914a3fa999
   email: eng@basho.com
 otp_release:
+  - 19.2
   - R16B02
   - R15B01
   - R15B
+env:
+  - REBAR_V=2
+  - REBAR_V=3
+before_install:
+  - ./ci before_install "${REBAR_V:?}"
+install:
+  - ./ci install "${REBAR_V:?}"
+script:
+  - ./ci script "${REBAR_V:?}"

ci

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+set -ev # Ref https://docs.travis-ci.com/user/customizing-the-build/#Implementing-Complex-Build-Steps
+
+case "${1:?}-${2:?}" in
+    before_install-2)
+        rebar version
+        ;;
+    before_install-3)
+        ## Travis CI does not support rebar3 yet. See https://github.com/travis-ci/travis-ci/issues/6506#issuecomment-275189490
+        curl -f -L -o ./rebar3 https://github.com/erlang/rebar3/releases/download/3.3.6/rebar3
+        chmod +x ./rebar3
+        ./rebar3 version
+        ;;
+    install-2)
+        rebar get-deps
+        ;;
+    install-3)
+        ./rebar3 deps
+        ;;
+    script-2)
+        rebar compile
+        test 1 -le $(find . -name syslog_drv.so | wc -l)
+        rebar eunit
+        ;;
+    script-3)
+        ./rebar3 compile
+        test 1 -le $(find . -name syslog_drv.so | wc -l)
+        ./rebar3 eunit
+        ./rebar3 dialyzer
+        ;;
+esac