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.
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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
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A proc that accepts a single positional argument and keywords will no longer autosplat. [Bug #18633]
proc{|a, **k| a}.call([1, 2]) # Ruby 3.1 and before # => 1 # Ruby 3.2 and after # => [1, 2]
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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
foois now called beforebaz. Similarly, for multiple assignments to constants, left-to-right evaluation order is used. With this code:foo1::BAR1, foo2::BAR2 = baz1, baz2
The following evaluation order is now used:
foo1foo2baz1baz2
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Find pattern is no longer experimental. [Feature #18585]
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Methods taking a rest parameter (like
*args) and wishing to delegate keyword arguments throughfoo(*args)must now be marked withruby2_keywords(if not already the case). In other words, all methods wishing to delegate keyword arguments through*argsmust now be marked withruby2_keywords, with no exception. This will make it easier to transition to other ways of delegation once a library can require Ruby 3+. Previously, theruby2_keywordsflag was kept if the receiving method took*args, but this was a bug and an inconsistency. A good technique to find the potentially-missingruby2_keywordsis to run the test suite, for where it fails find the last method which must receive keyword arguments, useputs nil, caller, nilthere, and check each method/block on the call chain which must delegate keywords is correctly marked asruby2_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)
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evaland related methods are able to generate code coverage. Enabled usingCoverage.setup(:all)orCoverge.setup(eval: true). [Feature #19008] -
Coverage.supported?(mode)enables detection of what coverage modes are supported. [Feature #19026]
Note: We're only listing outstanding class updates.
-
Fiber::Scheduler
- Introduce
Fiber::Scheduler#io_selectfor non-blockingIO.select. [Feature #19060]
- Introduce
-
IO
- Introduce
IO#timeout=andIO#timeoutwhich can causeIO::TimeoutErrorto be raised if a blocking operation exceeds the specified timeout. [Feature #18630]
STDIN.timeout = 1 STDIN.read # => Blocking operation timed out! (IO::TimeoutError)
- Introduce
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UNIXSocket
- Add support for
UNIXSocketon Windows. Emulate anonymous sockets. Add support forFile.socket?andFile::Stat#socket?where possible. [Feature #19135]
- Add support for
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Class
-
Class#attached_object, which returns the object for which the receiver is the singleton class. RaisesTypeErrorif the receiver is not a singleton class. [Feature #12084]class Foo; end Foo.singleton_class.attached_object #=> Foo Foo.new.singleton_class.attached_object #=> #<Foo:0x000000010491a370> Foo.attached_object #=> TypeError: `Foo' is not a singleton class nil.singleton_class.attached_object #=> TypeError: `NilClass' is not a singleton class
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-
Data
- New core class to represent simple immutable value object. The class is
similar to
Structand partially shares an implementation, but has more lean and strict API. [Feature #16122]
- New core class to represent simple immutable value object. The class is
similar to
-
Encoding
- Encoding#replicate has been deprecated and will be removed in 3.3. [Feature #18949]
- The dummy
Encoding::UTF_16andEncoding::UTF_32encodings no longer try to dynamically guess the endian based on a byte order mark. UseEncoding::UTF_16BE/UTF_16LEandEncoding::UTF_32BE/UTF_32LEinstead. This change speeds up getting the encoding of a String. [Feature #18949]
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Enumerator
- Enumerator.product has been added. Enumerator::Product is the implementation. [Feature #18685]
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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]
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Integer
- Integer#ceildiv has been added. [Feature #18809]
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Kernel
- Kernel#binding raises RuntimeError if called from a non-Ruby frame (such as a method defined in C). [Bug #18487]
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MatchData
- MatchData#byteoffset has been added. [Feature #13110]
- MatchData#deconstruct has been added. [Feature #18821]
- MatchData#deconstruct_keys has been added. [Feature #18821]
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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]
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Proc
- Proc#dup returns an instance of subclass. [Bug #17545]
- Proc#parameters now accepts lambda keyword. [Feature #15357]
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Process
- Added
RLIMIT_NPTSconstant to FreeBSD platform
- Added
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Regexp
- Regexp.new now supports passing the regexp flags not only as an Integer,
but also as a String. Unknown flags raise ArgumentError.
Otherwise, anything other than
true,false,nilor Integer will be warned. [Feature #18788]
- Regexp.new now supports passing the regexp flags not only as an Integer,
but also as a String. Unknown flags raise ArgumentError.
Otherwise, anything other than
-
Refinement
- Refinement#refined_class has been added. [Feature #12737]
-
RubyVM::AbstractSyntaxTree
- Add
error_tolerantoption forparse,parse_fileandof. [Feature #19013] - Add
keep_tokensoption forparse,parse_fileandof. Add#tokensand#all_tokensforRubyVM::AbstractSyntaxTree::Node[Feature #19070]
root = RubyVM::AbstractSyntaxTree.parse("x = 1 + 2", keep_tokens: true) root.tokens # => [[0, :tIDENTIFIER, "x", [1, 0, 1, 1]], [1, :tSP, " ", [1, 1, 1, 2]], ...] root.tokens.map{_1[2]}.join # => "x = 1 + 2"
- Add
-
Set
- Set is now available as a built-in class without the need for
require "set". [Feature #16989] It is currently autoloaded via theSetconstant or a call toEnumerable#to_set.
- Set is now available as a built-in class without the need for
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Socket
- Added the following constants for supported platforms.
SO_INCOMING_CPUSO_INCOMING_NAPI_IDSO_RTABLESO_SETFIBSO_USER_COOKIETCP_KEEPALIVETCP_CONNECTION_INFO
- Added the following constants for supported platforms.
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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]
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Struct
- A Struct class can also be initialized with keyword arguments
without
keyword_init: trueonStruct.new[Feature #16806]
- A Struct class can also be initialized with keyword arguments
without
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TracePoint
- TracePoint#binding now returns
nilforc_call/c_returnTracePoints. [Bug #18487] - TracePoint#enable
target_threadkeyword argument now defaults to the current thread iftargetandtarget_linekeyword arguments are not passed. [Bug #16889]
- TracePoint#binding now returns
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SyntaxSuggest
- The feature of
syntax_suggestformerlydead_endis integrated in Ruby. [Feature #18159]
- The feature of
-
The following default gems are updated.
- RubyGems 3.4.0.dev
- bigdecimal 3.1.2
- bundler 2.4.0.dev
- cgi 0.3.5
- date 3.2.3
- erb 3.0.0
- error_highlight 0.5.1
- etc 1.4.0
- fiddle 1.1.1
- io-console 0.5.11
- io-nonblock 0.1.1
- io-wait 0.3.0.pre
- ipaddr 1.2.4
- irb 1.5.0
- json 2.6.2
- logger 1.5.1
- net-http 0.3.0
- net-protocol 0.1.3
- openssl 3.1.0.pre
- ostruct 0.5.5
- psych 5.0.0.dev
- reline 0.3.1
- securerandom 0.2.0
- set 1.0.3
- stringio 3.0.3
- syntax_suggest 0.0.1
- timeout 0.3.0
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The following bundled gems are updated.
- minitest 5.16.3
- power_assert 2.0.2
- test-unit 3.5.5
- net-ftp 0.2.0
- net-imap 0.3.1
- net-pop 0.1.2
- net-smtp 0.3.3
- rbs 2.7.0
- typeprof 0.21.3
- debug 1.6.3
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The following default gems are now bundled gems.
Note: Excluding feature bug fixes.
The following deprecated constants are removed.
FixnumandBignum[Feature #12005]Random::DEFAULT[Feature #17351]Struct::GroupStruct::Passwd
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]
Source code incompatiblity of extension libraries [Bug #19100]
- Extension libraries provide PRNG, subclasses of
Random, need updates. See [PRNG update] below for more information.
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Psychno longer bundles libyaml sources. And alsoFiddleno longer bundles libffi sources. Users need to install the libyaml/libffi library themselves via the package manager like apt, yum, brew, etc.Psych and fiddle supported the static build with specific version of libyaml and libffi sources. You can build psych with libyaml-0.2.5 like this.
$ ./configure --with-libyaml-source-dir=/path/to/libyaml-0.2.5
And you can build fiddle with libffi-3.4.4 like this.
$ ./configure --with-libffi-source-dir=/path/to/libffi-3.4.4
The following APIs are updated.
-
PRNG update
rb_random_interface_tupdated and versioned. Extension libraries which use this interface and built for older versions. Alsoinit_int32function needs to be defined.
The following deprecated APIs are removed.
rb_cDatavariable.- "taintedness" and "trustedness" functions. [Feature #16131]
- Fixed several race conditions in
Kernel#autoload. [Bug #18782] - Cache invalidation for expressions referencing constants is now
more fine-grained.
RubyVM.stat(:global_constant_state)was removed because it was closely tied to the previous caching scheme where setting any constant invalidates all caches in the system. New keys,:constant_cache_invalidationsand:constant_cache_misses, were introduced to help with use cases for:global_constant_state. [Feature #18589]
- Support arm64 / aarch64 on UNIX platforms.
- Building YJIT requires Rust 1.58.0+. [Feature #18481]
- Physical memory for JIT code is lazily allocated. Unlike Ruby 3.1,
the RSS of a Ruby process is minimized because virtual memory pages
allocated by
--yjit-exec-mem-sizewill not be mapped to physical memory pages until actually utilized by JIT code. - Introduce Code GC that frees all code pages when the memory consumption
by JIT code reaches
--yjit-exec-mem-size. RubyVM::YJIT.runtime_statsreturns Code GC metrics in addition to existinginline_code_sizeandoutlined_code_sizekeys:code_gc_count,live_page_count,freed_page_count, andfreed_code_size.
- The MJIT compiler is re-implemented in Ruby as a standard library
mjit. - MJIT compiler is executed under a forked Ruby process instead of
doing it in a native thread called MJIT worker. [Feature #18968]
- As a result, Microsoft Visual Studio (MSWIN) is no longer supported.
- MinGW is no longer supported. [Feature #18824]
- Rename
--mjit-min-callsto--mjit-call-threshold.