NEWS for Ruby 3.2.0¶ ↑

This document is a list of user-visible feature changes since the 3.1.0 release, except for bug fixes.

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

Language changes¶ ↑

• Anonymous rest and keyword rest arguments can now be passed as arguments, instead of just used in method parameters. [Feature #18351]

  def foo(*)
    bar(*)
  end
  def baz(**)
    quux(**)
  end
  

• A proc that accepts a single positional argument and keywords will no longer autosplat. [Bug #18633]

ruby proc{|a, **k| a}.call([1, 2]) # Ruby 3.1 and before # => 1 # Ruby 3.2 and after # => [1, 2]

• Constant assignment evaluation order for constants set on explicit objects has been made consistent with single attribute assignment evaluation order. With this code:

  foo::BAR = baz
  

foo is now called before baz. Similarly, for multiple assignments to constants, left-to-right evaluation order is used. With this code:

```ruby
  foo1::BAR1, foo2::BAR2 = baz1, baz2
```

The following evaluation order is now used:

1. foo1

2. foo2

3. baz1

4. baz2

[Bug #15928]

• Find pattern is no longer experimental. [Feature #18585]

• Methods taking a rest parameter (like *args) and wishing to delegate keyword arguments through foo(*args) must now be marked with ruby2_keywords (if not already the case). In other words, all methods wishing to delegate keyword arguments through *args must now be marked with ruby2_keywords, with no exception. This will make it easier to transition to other ways of delegation once a library can require Ruby 3+. Previously, the ruby2_keywords flag was kept if the receiving method took *args, but this was a bug and an inconsistency. A good technique to find the potentially-missing ruby2_keywords is to run the test suite, for where it fails find the last method which must receive keyword arguments, use puts nil, caller, nil there, and check each method/block on the call chain which must delegate keywords is correctly marked as ruby2_keywords. [Bug #18625] [Bug #16466]

  def target(**kw)
  end
  
  # Accidentally worked without ruby2_keywords in Ruby 2.7-3.1, ruby2_keywords
  # needed in 3.2+. Just like (*args, **kwargs) or (...) would be needed on
  # both #foo and #bar when migrating away from ruby2_keywords.
  ruby2_keywords def bar(*args)
    target(*args)
  end
  
  ruby2_keywords def foo(*args)
    bar(*args)
  end
  
  foo(k: 1)
  

Command line options¶ ↑

Core classes updates¶ ↑

Note: We’re only listing outstanding class updates.

• Hash

  • Hash#shift now always returns nil if the hash is empty, instead of returning the default value or calling the default proc. [Bug #16908]

  • Hash#shift now always returns nil if the hash is empty, instead of returning the default value or calling the default proc. [Bug #16908]

• Kernel

  • Kernel#binding raises RuntimeError if called from a non-Ruby frame (such as a method defined in C). [Bug #18487]

• MatchData

  • MatchData#byteoffset has been added. [Feature #13110]

• Module

  • Module.used_refinements has been added. [Feature #14332]

  • Module#refinements has been added. [Feature #12737]

  • Module#const_added has been added. [Feature #17881]

  • Module#undefined_instance_methods has been added. [Feature #12655]

• Proc

  • Proc#dup returns an instance of subclass. [Bug #17545]

  • Proc#parameters now accepts lambda keyword. [Feature #15357]

• Regexp

  • Regexp.new now supports passing the regexp flags not only as an Integer, but also as a String Unknown flags raise errors. Otherwise, anything other than true, false, nil or Integer will be warned. [Feature #18788]

• Refinement

  • Refinement#refined_class has been added. [Feature #12737]

• Set

  • Set is now available as a built-in class without the need for require "set". [Feature #16989] It is currently autoloaded via the Set constant or a call to Enumerable#to_set.

• String

  • String#byteindex and String#byterindex have been added. [Feature #13110]

  • Update Unicode to Version 14.0.0 and Emoji Version 14.0. [Feature #18037] (also applies to Regexp)

  • String#bytesplice has been added. [Feature #18598]

• Struct

  • A Struct class can also be initialized with keyword arguments without keyword_init: true on Struct.new [Feature #16806]

• TracePoint

  • TracePoint#binding now returns nil for c_call/c_return TracePoints. [Bug #18487]

  • TracePoint#enable target_thread keyword argument now defaults to the current thread if target and target_line keyword arguments are not passed. [Bug #16889]

Stdlib updates¶ ↑

• The following default gems are updated.

  • RubyGems 3.4.0.dev

  • bigdecimal 3.1.2

  • bundler 2.4.0.dev

  • cgi 0.3.2

  • etc 1.4.0

  • io-console 0.5.11

  • io-nonblock 0.1.1

  • io-wait 0.2.3

  • ipaddr 1.2.4

  • json 2.6.2

  • logger 1.5.1

  • net-http 0.2.2

  • net-protocol 0.1.3

  • ostruct 0.5.5

  • psych 5.0.0.dev

  • reline 0.3.1

  • securerandom 0.2.0

  • stringio 3.0.3

  • timeout 0.3.0

• The following bundled gems are updated.

  • minitest 5.16.1

  • net-imap 0.2.3

  • rbs 2.5.1

  • typeprof 0.21.2

  • debug 1.5.0

• The following default gems are now bundled gems.

Compatibility issues¶ ↑

Note: Excluding feature bug fixes.

Removed constants¶ ↑

The following deprecated constants are removed.

• Fixnum and Bignum [Feature #12005]

• Random::DEFAULT [Feature #17351]

• Struct::Group

• Struct::Passwd

Removed methods¶ ↑

The following deprecated methods are removed.

• Dir.exists? [Feature #17391]

• File.exists? [Feature #17391]

• Kernel#=~ [Feature #15231]

• Kernel#taint, Kernel#untaint, Kernel#tainted? [Feature #16131]

• Kernel#trust, Kernel#untrust, Kernel#untrusted? [Feature #16131]

Stdlib compatibility issues¶ ↑

• Psych no longer bundles libyaml sources. Users need to install the libyaml library themselves via the package system. [Feature #18571]

C API updates¶ ↑

Removed C APIs¶ ↑

The following deprecated APIs are removed.

• rb_cData variable.

• “taintedness” and “trustedness” functions. [Feature #16131]

Implementation improvements¶ ↑

• Fixed several race conditions in Kernel#autoload. [Bug #18782]

JIT¶ ↑

MJIT¶ ↑

YJIT: New experimental in-process JIT compiler¶ ↑

Static analysis¶ ↑

RBS¶ ↑

TypeProf¶ ↑

Debugger¶ ↑

error_highlight¶ ↑

IRB Autocomplete and Document Display¶ ↑

Miscellaneous changes¶ ↑