Added RuboCop. (#165)

* Added RuboCop.

Signed-off-by: dblock <[email protected]>

.github/workflows/lint.yml

@@ -0,0 +1,15 @@
+name: Lint
+on: [push, pull_request]
+jobs:
+  rubocop:
+    name: RuboCop
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 2.5
+          bundler-cache: true
+      - run: bundle exec rubocop

.github/workflows/test-unreleased.yml

@@ -24,7 +24,6 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.entry.ruby_version }}
-
       - name: Checkout OpenSearch
         uses: actions/checkout@v3
         with:

.gitignore

@@ -1,3 +1,4 @@
+.bundle
 .config
 .yardoc
 _yardoc

.rubocop.yml

@@ -0,0 +1,18 @@
+inherit_from: .rubocop_todo.yml
+
+require:
+  - rubocop-rake
+  - rubocop-rspec
+
+AllCops:
+  TargetRubyVersion: 2.5
+  NewCops: enable
+
+RSpec/ImplicitExpect:
+  Enabled: false
+
+RSpec/ImplicitSubject:
+  Enabled: false
+
+Metrics:
+  Enabled: false