Rails6
Ruby Hash#transform_keys Accepts Key Mapping
Ruby Hash#transform_keys now also accepts a hash that maps the existing hash keys to new keysRails Adds Automatic Database Connection
Rails has added support for automatic database connection switching from primary to the replicaRails 6.1 perform_enqueued_jobs at Option
Rails 6.1 has added at option to perform_enqueued_jobs test helper to run only jobs which are scheduled at or before the passed in timeRails Disallowed Deprecations Support
Rails has added support to configure disallowed deprecations.Rails has added a benchmark generator
Rails has added a benchmark generator for scripts to benchmark Rails application.Rails 6 adds rails db:system:change command
Rails 6 adds rails db:system:change command to allow switching database configurationRails 6 ActiveSupport Unicode Deprecations
Rails 6 has deprecated methods in Unicode and Chars support for ActiveSupport in favor of using ruby 2.3+ String methods directly.Rails 6.1 Adds Multiple Storage Services
Rails 6.1 adds support to configure storage services for individual attachment.Webpacker is the new default in Rails 6
Webpacker is the new default JavaScript compiler instead of Sprockets in Rails 6Rails 6 adds ActiveSupport::ParameterFilter
Rails 6 has moved ParameterFilter from ActionDispatch to ActiveSupport in order to support filtered attributes with ActiveRecord::Relation#inspect.