Rails6

Ruby Hash#transform_keys now accepts a hash that maps existing keys to new keys

Ruby Hash#transform_keys now also accepts a hash that maps the existing hash keys to new keys

Rails has added support for automatic database connection switching from primary to the replica

Rails has added support for automatic database connection switching from primary to the replica

Rails 6.1 adds at option to perform_enqueued_jobs test helper

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 time

Rails introduces disallowed deprecations in ActiveSupport

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 configuration

Rails 6 - ActiveSupport Deprecations in Unicode and Chars support in favour of String

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 support for multiple storage services to Active Storage

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 6

Rails 6 adds ActiveSupport::ParameterFilter

Rails 6 has moved ParameterFilter from ActionDispatch to ActiveSupport in order to support filtered attributes with ActiveRecord::Relation#inspect.