NEWS for Ruby 3.3.0

This document is a list of user-visible feature changes
since the 3.2.0 (see #7517 for 3.2 support) release, except for bug fixes.

Note that each entry is kept to a minimum, see links for details.

Language changes

Command line options

• A new performance warning category was introduced.
  They are not displayed by default even in verbose mode.
  Turn them on with -W:performance or Warning[:performance] = true. [Feature #19538]

• A new RUBY_CRASH_REPORT environment variable was introduced to allow
  redirecting Ruby crash reports to a file or sub command. See the BUG REPORT ENVIRONMENT
  section of the ruby manpage for further details. [Feature #19790]

Core classes updates

Note: We're only listing outstanding class updates.

• Array

  • Array#pack now raises ArgumentError for unknown directives. [Bug #19150]

• Dir

  • Dir.for_fd added for returning a Dir object for the directory specified
    by the provided directory file descriptor. [Feature #19347]
  • Dir.fchdir added for changing the directory to the directory specified
    by the provided directory file descriptor. [Feature #19347]
  • Dir#chdir added for changing the directory to the directory specified by
    the provided Dir object. [Feature #19347]

• MatchData

  • MatchData#named_captures now accepts optional symbolize_names
    keyword. [Feature #19591]

• Module

  • Module#set_temporary_name added for setting a temporary name for a
    module. [Feature #19521]

• ObjectSpace::WeakKeyMap

  • New core class to build collections with weak references.
    The class use equality semantic to lookup keys like a regular hash,
    but it doesn't hold strong references on the keys. [Feature #18498]

• ObjectSpace::WeakMap

  • ObjectSpace::WeakMap#delete was added to eagerly clear weak map
    entries. [Feature #19561]

• Proc

  • Now Proc#dup and Proc#clone call #initialize_dup and #initialize_clone
    hooks respectively. [Feature #19362]

• Process

  • New Process.warmup method that notify the Ruby virtual machine that the boot sequence is finished,
    and that now is a good time to optimize the application. This is useful
    for long-running applications. The actual optimizations performed are entirely
    implementation-specific and may change in the future without notice. [Feature #18885]

• Process::Status

  • Process::Status#& and Process::Status#>> are deprecated. [Bug #19868]

• Queue

  • Queue#freeze now raises TypeError. [Bug #17146]

• Range

  • Range#reverse_each can now process beginless ranges with an Integer endpoint. [Feature #18515]
  • Range#reverse_each now raises TypeError for endless ranges. [Feature #18551]

• Refinement

  • Add Refinement#target as an alternative of Refinement#refined_class.
    Refinement#refined_class is deprecated and will be removed in Ruby
    3.4. [Feature #19714]

• SizedQueue

  • SizedQueue#freeze now raises TypeError. [Bug #17146]

• String

  • String#unpack now raises ArgumentError for unknown directives. [Bug #19150]
  • String#bytesplice now accepts new arguments index/length or range of the
    source string to be copied. [Feature #19314]

• TracePoint

  • TracePoint supports rescue event. When the raised exception was rescued,
    the TracePoint will fire the hook. rescue event only supports Ruby-level
    rescue. [Feature #19572] (Add support for a rescue trace event #7788)

Stdlib updates

• RubyGems and Bundler warn if users require gem that is scheduled to become the bundled gems
  in the future version of Ruby. [Feature #19351] [Feature #19776] [Feature #19843]

  Targeted libraries are:

  • abbrev
  • base64
  • bigdecimal
  • csv
  • drb
  • getoptlong
  • mutex_m
  • nkf
  • observer
  • racc
  • resolv-replace
  • rinda
  • syslog

• Socket#recv and Socket#recv_nonblock returns nil instead of an empty string on closed
  connections. Socket#recvmsg and Socket#recvmsg_nonblock returns nil instead of an empty packet on closed
  connections. [Bug #19012]

• Random::Formatter#alphanumeric is extended to accept optional chars
  keyword argument. [Feature #18183]

The following default gem is added.

• prism 0.18.0

The following default gems are updated.

• RubyGems 3.5.0.dev
• base64 0.2.0
• benchmark 0.3.0
• bigdecimal 3.1.5 (stubbed for JRuby)
• bundler 2.5.0.dev
• cgi 0.4.0
• csv 3.2.8
• date 3.3.4 (partially updated; stub JRuby gem)
• delegate 0.3.1
• drb 2.2.0
• english 0.8.0
• erb 4.0.3 (4.0.4 now, working through getting them to skip the ext on JRuby: https://github.com/ruby/erb/issues/52
• etc 1.4.3.dev.1 (no JRuby gem)
• fcntl 1.1.0 (no JRuby gem)
• fiddle 1.1.2
• fileutils 1.7.2
• find 0.2.0
• getoptlong 0.2.1
• io-console 0.6.1.dev.1
• irb 1.10.0
• json 2.7.0
• logger 1.6.0
• mutex_m 0.2.0
• net-http 0.4.0
• net-protocol 0.2.2
• nkf 0.1.3 (no JRuby gem)
• observer 0.1.2
• open-uri 0.4.0
• open3 0.2.0
• openssl 3.2.0 (no JRuby gem)
• optparse 0.4.0
• ostruct 0.6.0
• pathname 0.3.0 (no JRuby gem)
• pp 0.5.0
• prettyprint 0.2.0
• pstore 0.1.3
• psych 5.1.1.1
• rdoc 6.6.0
• reline 0.4.0
• rinda 0.2.0
• securerandom 0.3.0
• shellwords 0.2.0
• singleton 0.2.0
• stringio 3.1.1
• strscan 3.0.8
• syntax_suggest 1.1.0
• tempfile 0.2.0
• time 0.3.0
• timeout 0.4.1
• tmpdir 0.2.0 (no JRuby gem)
• tsort 0.2.0
• un 0.3.0
• uri 0.13.0
• weakref 0.1.3
• win32ole 1.8.10 (no JRuby gem)
• yaml 0.3.0
• zlib 3.1.0 (no JRuby gem)

The following bundled gem is promoted from default gems.

• racc 1.7.3

The following bundled gems are updated.

• minitest 5.20.0
• rake 13.1.0
• test-unit 3.6.1
• rexml 3.2.6
• rss 0.3.0
• net-imap 0.4.7
• net-smtp 0.4.0
• rbs 3.3.2 (no JRuby gem)
• typeprof 0.21.8 (no JRuby gem)
• debug 1.8.0 (no JRuby gem)

See GitHub releases like Logger or
changelog for details of the default gems or bundled gems.

Compatibility issues

• Subprocess creation/forking via the following file open methods is deprecated. [Feature #19630]

  • Kernel#open
  • URI.open
  • IO.binread
  • IO.foreach
  • IO.readlines
  • IO.read
  • IO.write

• When given a non-lambda, non-literal block, Kernel#lambda with now raises
  ArgumentError instead of returning it unmodified. These usages have been
  issuing warnings under the Warning[:deprecated] category since Ruby 3.0.0.
  [Feature #19777]

• The RUBY_GC_HEAP_INIT_SLOTS environment variable has been deprecated and
  removed. Environment variables RUBY_GC_HEAP_%d_INIT_SLOTS should be
  used instead. [Feature #19785]

Stdlib compatibility issues

• racc is promoted to bundled gems.
  • You need to add racc to your Gemfile if you use racc under bundler environment.
• ext/readline is retired
  • We have reline that is pure Ruby implementation compatible with ext/readline API. We rely on reline in the future. If you need to use ext/readline, you can install ext/readline via rubygems.org with gem install readline-ext.
  • We no longer need to install libraries like libreadline or libedit.
  • JRuby: Similar work will need to happen to unbundle the jruby-readline library. See Unbundle or rewrite jirb_swing #8066.

Implementation improvements

• defined?(@ivar) is optimized with Object Shapes.
• Name resolution such as Socket.getaddrinfo can now be interrupted. [Feature #19965]

Undocumented:

• New NameError handling of #message (Stop using receiver#inspect for "undefined method" errors ruby/ruby#6950)