Adding a Mention model, test stubs

spec/spec_helper.rb

@@ -0,0 +1,15 @@
+require 'simplecov'
+
+SimpleCov.start 'rails' do
+  add_group "Services", "app/services"
+end
+
+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  config.mock_with :rspec do |mocks|
+    mocks.verify_partial_doubles = true
+  end
+end