rspec-rails: add feature tests

rspec-rails.md

@@ -40,6 +40,9 @@ describe MyController do
       expect(response).to be_success
       expect(response).to have_http_status(200)
       expect(response).to render_template("index")
+      expect(response).to redirect_to '/..'
+
+      expect(assigns :article).to eq article
 
       response.status
     end
@@ -109,6 +112,20 @@ describe EventsHelper do
 end
 ```
 
+### Features
+
+```rb
+# spec/features/*.rb
+feature 'Signing in' do
+  background do
+    User.make email: 'hi@gmail.com'
+  end
+
+  scenario 'Signing in with credentials' do
+  end
+end
+```
+
 ### Matchers
 
 ```rb