Fix database connection to share with capybara

and the database cleaner to use transactions, not truncation

spec/support/database_cleaner.rb

@@ -1,6 +1,5 @@
 RSpec.configure do |config|
-
-  # database cleaner warning if you turn this off
+  # a warning if you turn this off
   config.before(:suite) do
     if config.use_transactional_fixtures?
       raise(<<-MSG)
@@ -17,26 +16,29 @@ RSpec.configure do |config|
 
     DatabaseCleaner.clean_with(:truncation)
   end
+
   config.before(:each) do
     DatabaseCleaner.strategy = :transaction
   end
-  # config.before(:suite) do
-  #   DatabaseCleaner.clean_with(:truncation)
-  # end
 
-  # config.before do
-  #   DatabaseCleaner.strategy = :transaction
-  # end
+  config.before(:each, type: :feature) do
+    # :rack_test driver's Rack app under test shares database connection
+    # with the specs, so continue to use transaction strategy for speed.
+    driver_shares_db_connection_with_specs = Capybara.current_driver == :rack_test
 
-  # config.before(:each, js: true) do
-  #   DatabaseCleaner.strategy = :truncation
-  # end
+    unless driver_shares_db_connection_with_specs
+      # Driver is probably for an external browser with an app
+      # under test that does *not* share a database connection with the
+      # specs, so use truncation strategy.
+      DatabaseCleaner.strategy = :truncation
+    end
+  end
 
-  # config.before do
-  #   DatabaseCleaner.start
-  # end
+  config.before(:each) do
+    DatabaseCleaner.start
+  end
 
-  # config.after do
-  #   DatabaseCleaner.clean
-  # end
+  config.append_after(:each) do
+    DatabaseCleaner.clean
+  end
 end