.travis.yml in pluck_map-0.2.1 vs .travis.yml in pluck_map-0.3.0

@@ -1,4 +1,22 @@
 language: ruby
-rvm:
-  - 2.1.2
-before_install: gem install bundler -v 1.10.6
+rvm: 2.5.5
+
+# Rails 6 requires Postgres 9.3+
+addons:
+  postgresql: "9.3"
+
+services:
+  - postgresql
+  - mysql
+
+# Test on supported versions of Rails + Edge Rails
+# (When Rails 6.0 is released, drop Rails 4.2)
+matrix:
+  include:
+  - gemfile: gemfiles/rails_4.2.gemfile
+  - gemfile: gemfiles/rails_5.0.gemfile
+  - gemfile: gemfiles/rails_5.1.gemfile
+  - gemfile: gemfiles/rails_5.2.gemfile
+  - gemfile: gemfiles/rails_edge.gemfile
+  allow_failures:
+  - gemfile: gemfiles/rails_edge.gemfile