Ruby on Rails v8.1.0.rc1 released!

NewsBot · 15 October 2025 02:25

Ruby on Rails v8.1.0.rc1 has been released.

Active Support

Remove deprecated passing a Time object to Time#since.

Rafael Mendonça França

Remove deprecated Benchmark.ms method. It is now defined in the benchmark gem.

Rafael Mendonça França

Remove deprecated addition for Time instances with ActiveSupport::TimeWithZone.

Rafael Mendonça França

Remove deprecated support for to_time to preserve the system local time. It will now always preserve the receiver
timezone.

Rafael Mendonça França

Deprecate config.active_support.to_time_preserves_timezone.

Rafael Mendonça França

Standardize event name formatting in assert_event_reported error messages.

The event name in failure messages now uses .inspect (e.g., name: "user.created")
to match assert_events_reported and provide type clarity between strings and symbols.
This only affects tests that assert on the failure message format itself.

George Ma

Fix Enumerable#sole to return the full tuple instead of just the first element of the tuple.

Olivier Bellone

Fix parallel tests hanging when worker processes die abruptly.

Previously, if a worker process was killed (e.g., OOM killed, kill -9) during parallel
test execution, the test suite would hang forever waiting for the dead worker.

Joshua Young

Add config.active_support.escape_js_separators_in_json.

Introduce a new framework default to skip escaping LINE SEPARATOR (U+2028) and PARAGRAPH SEPARATOR (U+2029) in JSON.

Historically these characters were not valid inside JavaScript literal strings but that changed in ECMAScript 2019.
As such it’s no longer a concern in modern browsers: JavaScript built-in: JSON: JavaScript is a superset of JSON | Can I use... Support tables for HTML5, CSS3, etc.

Étienne Barrié, Jean Boussier

Fix NameError when class_attribute is defined on instance singleton classes.

Previously, calling `class_att…

Link: Release 8.1.0.rc1 · rails/rails · GitHub