Added support for building in GitLab CI

.gitlab-ci.yml

@@ -0,0 +1,59 @@
+# Cache gems in between builds
+cache:
+  paths:
+     - vendor
+
+variables:
+  LANG: "C.UTF-8"
+  REDIS_HOST: "redis"
+  REDIS_PORT: "6379"
+
+.test-template: &test-common
+  services:
+    - redis:latest
+  before_script:
+    - gem update --system --no-document
+    - gem install bundler --no-ri --no-rdoc
+    - bundle install -j $(nproc) --path vendor --retry 3
+
+test:2.0:
+  image: "ruby:2.0"
+  <<: *test-common
+  script:
+    - bundle exec rake
+
+test:2.1:
+  image: "ruby:2.1"
+  <<: *test-common
+  script:
+    - bundle exec rake
+
+test:2.2:
+  image: "ruby:2.2"
+  <<: *test-common
+  script:
+    - bundle exec rake
+
+test:2.3:
+  image: "ruby:2.3"
+  <<: *test-common
+  script:
+    - bundle exec rake
+
+test:jruby-9.1:
+  image: "jruby:9.1"
+  services:
+    - redis:latest
+  before_script:
+    - jgem update --system --no-document
+    - jgem install bundler --no-ri --no-rdoc
+    - bundle install -j $(nproc) --path vendor --retry 3
+  script:
+    - bundle exec rake
+  allow_failure: true
+
+test:rubinius-latest:
+  image: "rubinius/docker:latest"
+  script:
+    - bundle exec rake
+  allow_failure: true

lib/lita/default_configuration.rb

@@ -75,7 +75,11 @@ def http_config
 
     # Builds config.redis
     def redis_config
-      root.config :redis, type: Hash, default: {}
+      # Overrides Redis host/port defined by ENVIRONMENT variables
+      default = {}
+      default[:host] = ENV["REDIS_HOST"] if ENV["REDIS_HOST"]
+      default[:port] = ENV["REDIS_PORT"] if ENV["REDIS_PORT"]
+      root.config :redis, type: Hash, default: default
     end
 
     # Builds config.robot

spec/lita/default_configuration_spec.rb

@@ -117,8 +117,27 @@
   end
 
   describe "redis config" do
-    it "has empty default options" do
-      expect(config.redis).to eq({})
+    before do
+      allow(ENV).to receive(:[]).with("REDIS_HOST") { nil }
+      allow(ENV).to receive(:[]).with("REDIS_PORT") { nil }
+    end
+
+    context "with no specific environmental variables" do
+      it "has empty default options" do
+        expect(config.redis).to eq({})
+      end
+    end
+
+    context "with specific environmental variables" do
+      it "defines a default redis host based on REDIS_HOST env variable" do
+        allow(ENV).to receive(:[]).with("REDIS_HOST") { "myredis" }
+        expect(config.redis).to eq(host: "myredis")
+      end
+
+      it "defines a default redis port based on REDIS_PORT env variable" do
+        allow(ENV).to receive(:[]).with("REDIS_PORT") { "6380" }
+        expect(config.redis).to eq(port: "6380")
+      end
     end
 
     it "can set options" do