Posted by naruse on 6 Dec 2022
We are pleased to announce the release of Ruby 3.2.0-rc1. Ruby 3.2 adds many features and performance improvements.
WASI based WebAssembly support
This is an initial port of WASI based WebAssembly support. This enables a CRuby binary to be available on a Web browser, a Serverless Edge environment, or other kinds of WebAssembly/WASI embedders. Currently this port passes basic and bootstrap test suites not using the Thread API.
Background
WebAssembly (Wasm) was originally introduced to run programs safely and fast in web browsers. But its objective - running programs efficiently with security on various environment - is long wanted not only for web but also by general applications.
WASI (The WebAssembly System Interface) is designed for such use cases. Though such applications need to communicate with operating systems, WebAssembly runs on a virtual machine which didn’t have a system interface. WASI standardizes it.
WebAssembly/WASI support in Ruby intends to leverage those projects. It enables Ruby developers to write applications which run on such promised platforms.
Use case
This support encourages developers to utilize CRuby in a WebAssembly environment. An example use case is TryRuby playground’s CRuby support. Now you can try original CRuby in your web browser.
Technical points
Today’s WASI and WebAssembly itself is missing some features to implement Fiber, exception, and GC because it’s still evolving, and also for security reasons. So CRuby fills the gap by using Asyncify, which is a binary transformation technique to control execution in userland.
In addition, we built a VFS on top of WASI so that we can easily pack Ruby apps into a single .wasm file. This makes distribution of Ruby apps a bit easier.
Related links
Regexp improvements against ReDoS
It is known that Regexp matching may take unexpectedly long. If your code attempts to match a possibly inefficient Regexp against an untrusted input, an attacker may exploit it for efficient Denial of Service (so-called Regular expression DoS, or ReDoS).
We have introduced two improvements that significantly mitigate ReDoS.
Improved Regexp matching algorithm
Since Ruby 3.2, Regexp’s matching algorithm has been greatly improved by using a memoization technique.
# This match takes 10 sec. in Ruby 3.1, and 0.003 sec. in Ruby 3.2
/^a*b?a*$/ =~ "a" * 50000 + "x"
The improved matching algorithm allows most Regexp matching (about 90% in our experiments) to be completed in linear time.
(For preview users: this optimization may consume memory proportional to the input length for each match. We expect no practical problems to arise because this memory allocation is usually delayed, and a normal Regexp match should consume at most 10 times as much memory as the input length. If you run out of memory when matching Regexps in a real-world application, please report it.)
The original proposal is https://bugs.ruby-lang.org/issues/19104
Regexp timeout
The optimization above cannot be applied to some kind of regular expressions, such as those including advanced features (e.g., back-references or look-around), or with a huge fixed number of repetitions. As a fallback measure, a timeout feature for Regexp matches is also introduced.
Regexp.timeout = 1.0
/^a*b?a*()\1$/ =~ "a" * 50000 + "x"
#=> Regexp::TimeoutError is raised in one second
Note that Regexp.timeout
is a global configuration. If you want to use different timeout settings for some special Regexps, you may want to use the timeout
keyword for Regexp.new
.
Regexp.timeout = 1.0
# This regexp has no timeout
long_time_re = Regexp.new('^a*b?a*()\1$', timeout: Float::INFINITY)
long_time_re =~ "a" * 50000 + "x" # never interrupted
The original proposal is https://bugs.ruby-lang.org/issues/17837
Other Notable New Features
SyntaxSuggest
-
The feature of
syntax_suggest
(formerlydead_end
) is integrated into Ruby. This helps you find the position of errors such as missing or superfluousend
s, to get you back on your way faster, such as in the following example:Unmatched `end', missing keyword (`do', `def`, `if`, etc.) ? 1 class Dog > 2 defbark > 4 end 5 end
ErrorHighlight
- Now it points at the relevant argument(s) for TypeError and ArgumentError
test.rb:2:in `+': nil can't be coerced into Integer (TypeError)
sum = ary[0] + ary[1]
^^^^^^
Language
-
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]
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 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:
foo1
foo2
baz1
baz2
-
The find pattern is no longer experimental. [Feature #18585]
-
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*args
must 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_keywords
flag was kept if the receiving method took*args
, but this was a bug and an inconsistency. A good technique to find potentially missingruby2_keywords
is to run the test suite, find the last method which must receive keyword arguments for each place where the test suite fails, and useputs nil, caller, nil
there. Then check that each method/block on the call chain which must delegate keywords is correctly marked withruby2_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)
Performance improvements
YJIT
- YJIT now supports both x86-64 and arm64/aarch64 CPUs on Linux, MacOS, BSD and other UNIX platforms.
- This release brings support for Mac M1/M2, AWS Graviton and Raspberry Pi 4 ARM64 processors.
- Building YJIT requires Rust 1.58.0+. [Feature #18481]
- In order to ensure that CRuby is built with YJIT, please install rustc >= 1.58.0 and
run
./configure
with--enable-yjit
. - Please reach out to the YJIT team should you run into any issues.
- In order to ensure that CRuby is built with YJIT, please install rustc >= 1.58.0 and
run
- 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-size
will 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_stats returns Code GC metrics in addition to
existing
inline_code_size
andoutlined_code_size
keys:code_gc_count
,live_page_count
,freed_page_count
, andfreed_code_size
.
- RubyVM::YJIT.runtime_stats returns Code GC metrics in addition to
existing
- Most of the statistics produced by RubyVM::YJIT.runtime_stats are now available in release builds.
- Simply run ruby with
--yjit-stats
to compute stats (incurs some run-time overhead).
- Simply run ruby with
- YJIT is now optimized to take advantage of object shapes. [Feature #18776]
- Take advantage of finer-grained constant invalidation to invalidate less code when defining new constants. [Feature #18589]
MJIT
- 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-calls
to--mjit-call-threshold
. - Change default
--mjit-max-cache
back from 10000 to 100.
PubGrub
-
Bundler 2.4 now uses PubGrub resolver instead of Molinillo.
- PubGrub is the next generation solving algorithm used by
pub
package manager for the Dart programming language. - You may get different resolution result after this change. Please report such cases to RubyGems/Bundler issues
- PubGrub is the next generation solving algorithm used by
-
RubyGems still uses Molinillo resolver in Ruby 3.2. We plan to replace it with PubGrub in the future.
Other notable changes since 3.1
- 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]
- 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]
- Proc
- Proc#dup returns an instance of subclass. [Bug #17545]
- Proc#parameters now accepts lambda keyword. [Feature #15357]
- Refinement
- Refinement#refined_class has been added. [Feature #12737]
- RubyVM::AbstractSyntaxTree
- Add
error_tolerant
option forparse
,parse_file
andof
. [[Feature #19013]]
- Add
- Set
- Set is now available as a builtin class without the need for
require "set"
. [Feature #16989] It is currently autoloaded via theSet
constant or a call toEnumerable#to_set
.
- Set is now available as a builtin class without the need for
- String
- String#byteindex and String#byterindex have been added. [Feature #13110]
- Update Unicode to Version 15.0.0 and Emoji Version 15.0. [Feature #18639] (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
onStruct.new
[Feature #16806]
- A Struct class can also be initialized with keyword arguments
without
Compatibility issues
Note: Excluding feature bug fixes.
Removed constants
The following deprecated constants are removed.
Fixnum
andBignum
[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
No longer bundle 3rd party sources
-
We no longer bundle 3rd party sources like
libyaml
,libffi
.-
libyaml source has been removed from psych. You may need to install
libyaml-dev
with Ubuntu/Debian platform. The package name is different for each platform. -
Bundled libffi source is also removed from
fiddle
-
-
Psych and fiddle supported static builds with specific versions 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
C API updates
Updated C APIs
The following APIs are updated.
- PRNG update
rb_random_interface_t
updated and versioned. Extension libraries which use this interface and built for older versions. Alsoinit_int32
function needs to be defined.
Removed C APIs
The following deprecated APIs are removed.
rb_cData
variable.- “taintedness” and “trustedness” functions. [Feature #16131]
Standard library updates
- The following default gems are updated.
- RubyGems 3.4.0.dev
- benchmark 0.2.1
- bigdecimal 3.1.3
- bundler 2.4.0.dev
- cgi 0.3.6
- date 3.3.0
- delegate 0.3.0
- did_you_mean 1.6.2
- digest 3.1.1
- drb 2.1.1
- erb 4.0.2
- error_highlight 0.5.1
- etc 1.4.1
- fcntl 1.0.2
- fiddle 1.1.1
- fileutils 1.7.0
- forwardable 1.3.3
- getoptlong 0.2.0
- io-console 0.5.11
- io-nonblock 0.2.0
- io-wait 0.3.0.pre
- ipaddr 1.2.5
- irb 1.5.1
- json 2.6.2
- logger 1.5.2
- mutex_m 0.1.2
- net-http 0.3.1
- net-protocol 0.2.0
- nkf 0.1.2
- open-uri 0.3.0
- openssl 3.1.0.pre
- optparse 0.3.0
- ostruct 0.5.5
- pathname 0.2.1
- pp 0.4.0
- pstore 0.1.2
- psych 5.0.0
- racc 1.6.1
- rdoc 6.5.0
- reline 0.3.1
- resolv 0.2.2
- securerandom 0.2.1
- set 1.0.3
- stringio 3.0.3
- syntax_suggest 1.0.1
- timeout 0.3.1
- tmpdir 0.1.3
- tsort 0.1.1
- un 0.2.1
- uri 0.12.0
- win32ole 1.8.9
- zlib 3.0.0
- 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 2.8.1
- typeprof 0.21.3
- debug 1.7.0
See NEWS or commit logs for more details.
With those changes, 2846 files changed, 203950 insertions(+), 127153 deletions(-) since Ruby 3.1.0!
Download
-
https://cache.ruby-lang.org/pub/ruby/3.2/ruby-3.2.0-rc1.tar.gz
SIZE: 20253652 SHA1: 9b45af61ef1ae3c21ab88d7c9e30b80060116ac3 SHA256: 3bb9760c1ac1b66416aaa4899809f6ccd010e57038eaaeca19a383fd56275dac SHA512: 798157d785ebae94cb128d3c134fa35e0e90c654972e531cb6562823042f3fb68a270226f7b1cf0c42572ef2b1488a1a3e44f88389ad2a6f9ca4b280a2a8e759
-
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-
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SIZE: 24473024 SHA1: 8fdc85363ce61e0b8f04da36e709d49028d04a75 SHA256: 7ff32473be108534548e401aaa9092c37a27f73323ea4091c33901c714c87ee5 SHA512: 07adf6a9c89fdcf420e7b131f40f2b1f4aca036aa6f28539ade26ca552f84a75e0698f77a8b774d2ea52b8c756c4982ef319bda5afa786c081a31dd9873c5ef7
What is Ruby
Ruby was first developed by Matz (Yukihiro Matsumoto) in 1993, and is now developed as Open Source. It runs on multiple platforms and is used all over the world especially for web development.