Track RSpec failures to easily retry them when debugging

Author: shepmaster

tests/spec/spec_helper.rb

@@ -1,3 +1,5 @@
+require 'tmpdir'
+
 RSpec.configure do |config|
   config.expect_with :rspec do |expectations|
     expectations.include_chain_clauses_in_custom_matcher_descriptions = true
@@ -17,6 +19,8 @@
     config.default_formatter = 'doc'
   end
 
+  config.example_status_persistence_file_path = "#{Dir.tmpdir()}/playground-test-failures"
+
   config.order = :random
 
   Kernel.srand config.seed