January 2026 - ruby-core - ml.ruby-lang.org

[ruby-core:124497] [Ruby Feature#21835] Unbundle bunled gems like net-ftp
by hsbt (Hiroshi SHIBATA) 24 Feb '26

24 Feb '26

Issue #21835 has been reported by hsbt (Hiroshi SHIBATA). ---------------------------------------- Feature #21835: Unbundle bunled gems like net-ftp https://bugs.ruby-lang.org/issues/21835 * Author: hsbt (Hiroshi SHIBATA) * Status: Open ---------------------------------------- I would like to unundle the following bundled gems: * net-ftp * net-pop * prime The main purpose of bundled gems is to ensure their functionality by running tests with ruby head every time. However, the above gems for older protocols or purposes should be handled the same as other regular gems. -- https://bugs.ruby-lang.org/

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[ruby-core:117027] [Ruby master Bug#20319] Singleton class is being frozen lazily in some cases
by andrykonchin (Andrew Konchin) 24 Feb '26

24 Feb '26

Issue #20319 has been reported by andrykonchin (Andrew Konchin). ---------------------------------------- Bug #20319: Singleton class is being frozen lazily in some cases https://bugs.ruby-lang.org/issues/20319 * Author: andrykonchin (Andrew Konchin) * Status: Open * ruby -v: 3.2.2 * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- I've noticed suspicious behaviour (it doesn't affect anything in practice for me though) when an object becomes frozen only its own singleton class becomes frozen immediately. A singleton class of the immediate singleton class becomes frozen lazily after `#singleton_class` method call: ```ruby o = Object.new klass = o.singleton_class.singleton_class o.freeze puts klass.frozen? # false <== here we expect true puts o.singleton_class.singleton_class.frozen? # true puts klass.frozen? # true ``` I would expect all created singleton classes in an object singleton classes chain to become frozen immediately. -- https://bugs.ruby-lang.org/

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[ruby-core:124646] [Ruby Bug#21855] Bundle `win32-registry` or implement it without `fiddle`
by Earlopain (Earlopain _) 20 Feb '26

20 Feb '26

Issue #21855 has been reported by Earlopain (Earlopain _). ---------------------------------------- Bug #21855: Bundle `win32-registry` or implement it without `fiddle` https://bugs.ruby-lang.org/issues/21855 * Author: Earlopain (Earlopain _) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- `win32-registry` (a default gem), is currently implemented via `fiddle` (a bundled gem). This makes it impossible to use under bundler without adding `fiddle` to the gemfile. In the past it has lead to issues like https://bugs.ruby-lang.org/issues/21645. It was solved by simply not using `win32-registry` anymore in `resolv` and implementing it via C (https://github.com/ruby/resolv/pull/110) although the overarching issue is still present. There is also a report for this for rubygems https://github.com/ruby/rubygems/issues/9277. This should be solved by updating the vendored `resolv` version I think. Still, the dependecy relation between `win32-registry` and `fiddle` is pretty incompatible. A default gem can't depend on a bundled gem without breaking dependency resolution. To solve this it would have to be implemented without using `fiddle`, similar to how `resolv` did it. But now that `resolv` doesn't use `win32-registry`, I don't think anything in ruby uses it anymore. So moving it to a bundled gem could also be a solution without rewriting the whole thing. Here is an issue about this in the `win32-registry` repo: https://github.com/ruby/win32-registry/issues/11 -- https://bugs.ruby-lang.org/

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[ruby-core:115196] [Ruby master Feature#19979] Allow methods to declare that they don't accept a block via `&nil`
by ufuk (Ufuk Kayserilioglu) 15 Feb '26

15 Feb '26

Issue #19979 has been reported by ufuk (Ufuk Kayserilioglu). ---------------------------------------- Feature #19979: Allow methods to declare that they don't accept a block via `&nil` https://bugs.ruby-lang.org/issues/19979 * Author: ufuk (Ufuk Kayserilioglu) * Status: Open * Priority: Normal ---------------------------------------- ## Abstract This feature proposes new syntax to allow methods to explicitly declare that they don't accept blocks, and makes passing of a block to such methods an error. ## Background In #15554, it was proposed to automatically detect methods that do not use the block passed to them, and to error if a block was passed to such methods. As far as I can tell, it was later on closed since #10499 solved a large part of the problem. That proposal has, as part of the dev meeting discussion, a proposal from @matz to allow methods to use `&nil` to explicitly declare that they don't accept a block. At the time, the proposal was trying to solve a bigger problem, so this sub-proposal was never considered seriously. However, notes in the proposal say: > It is explicit, but it is tough to add this `&nil` parameter declaration to all of methods (do you want to add it to `def []=(i, e, &nil)`?). (I agree `&nil` is valuable on some situations) This proposal extracts that sub-proposal to make this a new language feature. ## Proposal In Ruby, it is always valid for the caller to pass a block to a method call, even if the callee is not expecting a block to be passed. This leads to subtle user errors, where the author of some code assumes a method call uses a block, but the block passed to the method call is silently ignored. The proposal is to introduce `&nil` at method declaration sites to mean "This method does not accept a block". This is symmetric to the ability to pass `&nil` at call sites to mean "I am not passing a block to this method call", which is sometimes useful when making `super` calls (since blocks are always implicitly passed). Explicitly, the proposal is to make the following behaviour be a part of Ruby: ```ruby def find(item = nil, &nil) # some implementation that doesn't call `yield` or `block_given?` end find { |i| i == 42 } # => ArgumentError: passing block to the method `find' that does not accept a block. ``` ## Implementation I assume the implementation would be a grammar change to make `&nil` valid at method declaration sites, as well as raising an `ArgumentError` for methods that are called with a block but are declared with `&nil`. ## Evaluation Since I don't have an implementation, I can't make a proper evaluation of the feature proposal. However, I would expect the language changes to be minimal with no runtime costs for methods that don't use the `&nil` syntax. ## Discussion This proposal has much smaller scope than #15554 so that the Ruby language can start giving library authors the ability to explicitly mark their methods as not accepting a block. This is fully backward compatible, since it is an opt-in behaviour and not an opt-out one. Future directions after this feature proposal could be a way to signal to the VM that any method in a file that doesn't explicitly use `yield`/`block_given?` or explicitly declared a block parameter should be treated as not accepting a block. This can be done via some kind of pragma similar to `frozen_string_literal`, or through other means. However, such future directions are beyond the scope of this proposal. ## Summary Adding the ability for methods to declare that they don't accept a block will make writing code against such methods safer and more resilient, and will prevent silently ignored behaviour that is often hard to catch or troubleshoot. -- https://bugs.ruby-lang.org/

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[ruby-core:124461] [Ruby Bug#21830] Ruby::Box and Kernel#require
by fxn (Xavier Noria) 15 Feb '26

15 Feb '26

Issue #21830 has been reported by fxn (Xavier Noria). ---------------------------------------- Bug #21830: Ruby::Box and Kernel#require https://bugs.ruby-lang.org/issues/21830 * Author: fxn (Xavier Noria) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- If you enable `Ruby::Box`, decorations to `Kernel#require` do not work. For example, given `foo.rb`: ```ruby # foo.rb % cat foo.rb module M def require(_path) puts "decorated" super end end Kernel.prepend(M) require 'tsort' ``` the decoration works normally: ``` % ruby -v foo.rb ruby 4.0.0 (2025-12-25 revision 553f1675f3) +YJIT +PRISM [arm64-darwin25] decorated ``` and the same code does not work with the feature enabled: ``` % RUBY_BOX=1 ruby -v foo.rb ruby 4.0.0 (2025-12-25 revision 553f1675f3) +YJIT +PRISM [arm64-darwin25] ruby: warning: Ruby::Box is experimental, and the behavior may change in the future! See https://docs.ruby-lang.org/en/4.0/Ruby/Box.html for known issues, etc. ``` With this, Zeitwerk cannot work because it totally depends on `Kernel#require` decoration (done [here](https://github.com/fxn/zeitwerk/blob/main/lib/zeitwerk/core_ext/kerne…) Bootsnap also depends on the ability of decorating `Kernel#require` (done [here](https://github.com/rails/bootsnap/blob/main/lib/bootsnap/load_path_ca…) On one hand, these gems are walking a fine line in the border of the public interface of Ruby. On the other hand, it is a goal of boxes to be transparent to the code being loaded under them. @tagomoris what should be the way to go in your opinion? /cc @byroot -- https://bugs.ruby-lang.org/

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[ruby-core:121988] [Ruby Bug#21324] Namespace loads RubyGems in root Namespace but it should not
by Eregon (Benoit Daloze) 15 Feb '26

15 Feb '26

Issue #21324 has been reported by Eregon (Benoit Daloze). ---------------------------------------- Bug #21324: Namespace loads RubyGems in root Namespace but it should not https://bugs.ruby-lang.org/issues/21324 * Author: Eregon (Benoit Daloze) * Status: Open * ruby -v: ruby 3.5.0dev (2025-05-10T07:50:29Z namespace-on-read-.. bd4f57f96b) +PRISM [x86_64-linux] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- RubyGems has tons of mutable state, isn't core library and isn't "builtin classes" either, so it should not be in root Namespace, as it is currently: ``` $ RUBY_NAMESPACE=1 ruby -ve 'ns = Namespace.new; p ns::Gem.equal?(Gem)' ruby 3.5.0dev (2025-05-10T07:50:29Z namespace-on-read-.. bd4f57f96b) +PRISM [x86_64-linux] ruby: warning: Namespace is experimental, and the behavior may change in the future! See doc/namespace.md for know issues, etc. true ``` A concrete example of what breaks most likely due to this: ``` $ gem i delegate:0.3.1 $ RUBY_NAMESPACE=1 ruby -ve 'require "delegate"; p Delegator::VERSION; ns = Namespace.new; File.write "ns.rb", "gem %{delegate}, %{0.3.1}; require :delegate.to_s; p Delegator::VERSION"; ns.require "./ns"' ruby 3.5.0dev (2025-05-10T07:50:29Z namespace-on-read-.. bd4f57f96b) +PRISM [x86_64-linux] ruby: warning: Namespace is experimental, and the behavior may change in the future! See doc/namespace.md for know issues, etc. "0.4.0" /home/eregon/prefix/ruby-master/lib/ruby/3.5.0+0/rubygems/specification.rb:2232:in 'Gem::Specification#check_version_conflict': can't activate delegate-0.3.1, already activated delegate-0.4.0 (Gem::LoadError) from /home/eregon/prefix/ruby-master/lib/ruby/3.5.0+0/rubygems/specification.rb:1383:in 'Gem::Specification#activate' from /home/eregon/prefix/ruby-master/lib/ruby/3.5.0+0/rubygems/core_ext/kernel_gem.rb:62:in 'block in Kernel#gem' from /home/eregon/prefix/ruby-master/lib/ruby/3.5.0+0/rubygems/core_ext/kernel_gem.rb:62:in 'Thread::Mutex#synchronize' from /home/eregon/prefix/ruby-master/lib/ruby/3.5.0+0/rubygems/core_ext/kernel_gem.rb:62:in 'Kernel#gem' from /home/eregon/ns.rb:1:in '<top (required)>' from -e:1:in 'Namespace#require' from -e:1:in '<main>' ``` i.e. `ns` sees delegate-0.4.0 was loaded in main namespace but it shouldn't. Previously mentioned in https://bugs.ruby-lang.org/issues/21311#note-36 -- https://bugs.ruby-lang.org/

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[ruby-core:124198] [Ruby Feature#21781] Add `fetch_values` method on `ENV`
by Earlopain (Earlopain _) 14 Feb '26

14 Feb '26

Issue #21781 has been reported by Earlopain (Earlopain _). ---------------------------------------- Feature #21781: Add `fetch_values` method on `ENV` https://bugs.ruby-lang.org/issues/21781 * Author: Earlopain (Earlopain _) * Status: Open ---------------------------------------- In https://bugs.ruby-lang.org/issues/10017, `fetch_values` was introduced for `Hash`. `ENV` is hash-like but is missing the method. Here are the differences between hash and env right now: ```rb irb(main):006> Hash.instance_methods - ENV.methods => [:merge, :compare_by_identity, :compare_by_identity?, :>=, :deconstruct_keys, :dig, :<=, :>, :<, :to_proc, :flatten, :compact!, :default=, :default_proc, :default_proc=, :default, :transform_keys, :transform_keys!, :transform_values!, :fetch_values, :transform_values] ``` `flatten`/`dig` among others make no sense for `ENV`. Some I don't see why they are not present but I won't argue for them since I have no use-case. Here is code I wanted to write: ```rb # Get many env variables and crash if one is missing user, pass, year, target_dir = ENV.fetch_values("USER", "PASS", "YEAR", "TARGET_DIR") ``` For now I am simply adding `to_h` and all is good. But should I have to? Ignoring a small amount of methods, ENV is very close to a hash already. -- https://bugs.ruby-lang.org/

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[ruby-core:124342] [Ruby Feature#21800] `Dir.foreach` and `Dir.each_child` to optionally yield `File::Stat` object alongside the children name
by byroot (Jean Boussier) 13 Feb '26

13 Feb '26

Issue #21800 has been reported by byroot (Jean Boussier). ---------------------------------------- Feature #21800: `Dir.foreach` and `Dir.each_child` to optionally yield `File::Stat` object alongside the children name https://bugs.ruby-lang.org/issues/21800 * Author: byroot (Jean Boussier) * Status: Open ---------------------------------------- When listing a directory, it's very common to need to know the type of each children, generally because you want to scan recursively. The naive way to do this is to call `stat(2)` for each children, but this is quite costly. This use case is common enough that `readdir` on most modern platforms do expose `struct dirent.d_type`, which allows to know the type of the child without an extra syscall. I wrote a quick prototype, and relying on `dirent.d_type` instead of `stat(2)` allows to recursively scan Ruby's repository twice as fast on my machine: https://github.com/ruby/ruby/pull/15667 Given that recursively scanning directories is a common task across many popular ruby tools (`zeitwerk`, `rubocop`, etc), I think it would be very valuable to provide this more efficient interface. In addition, @nobu noticed my prototype, and implemented a nicer version of it, where a `File::Stat` is yielded: https://github.com/ruby/ruby/commit/9acf67057b9bc6f855b2c37e41c1a2f91eae643a In that case the `File::Stat` is lazy, it's only if you access something other than file type, that the actual `stat(2)` call is emitted. I think this API is both more efficient and more convenient. ### Proposed API ```ruby Dir.foreach(path) { |name| } Dir.foreach(path) { |name, stat| } Dir.each_child(path) { |name| } Dir.each_child(path) { |name| } Dir.new(path).each_child { |name, stat| } Dir.new(path).each_child { |name, stat| } Dir.new(path).each { |name, stat| } Dir.new(path).each { |name, stat| } ``` Also important to note, the `File::Stat` is expected to be equivalent to a `lstat(2)` call, as to be able to chose to follow symlinks or not. Basic use case: ```ruby def count_ruby_files(root) count = 0 queue = [root] while dir = queue.pop Dir.(dir) do |name, stat| next if name.start_with?(".") if stat.directory? queue << File.join(dir, name) elsif stat.file? count += 1 if name.end_with?(".rb") end end end count end ``` -- https://bugs.ruby-lang.org/

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[ruby-core:123433] [Ruby Misc#21630] Suggest @Earlopain for core contributor
by kddnewton (Kevin Newton) 12 Feb '26

12 Feb '26

Issue #21630 has been reported by kddnewton (Kevin Newton). ---------------------------------------- Misc #21630: Suggest @Earlopain for core contributor https://bugs.ruby-lang.org/issues/21630 * Author: kddnewton (Kevin Newton) * Status: Open ---------------------------------------- @Earlopain has been prolifically contributing to Prism for over a year, in addition to other various changes around ruby/ruby, like [96fdaf2e](https://github.com/ruby/ruby/commit/96fdaf2e393933fdd128cd1a41fa9…, [3826019f](https://github.com/ruby/ruby/commit/3826019f310991aedf0612408d7b8…, [a82e7132](https://github.com/ruby/ruby/commit/a82e7132df71bd99b5d02c0c8a348…, and [many more](https://github.com/ruby/ruby/commits/master/?author=Earlopain). I would very much like @Earlopain to be able to merge their own contributions to Ruby, since they have been of such high quality for so long. -- https://bugs.ruby-lang.org/

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[ruby-core:124385] [Ruby Feature#21813] Add [:forward, :...] symbol tuple to indicate forwarding arguments when calling `Method#parameters`
by pabloh (Pablo Herrero) 12 Feb '26

12 Feb '26

Issue #21813 has been reported by pabloh (Pablo Herrero). ---------------------------------------- Feature #21813: Add [:forward, :...] symbol tuple to indicate forwarding arguments when calling `Method#parameters` https://bugs.ruby-lang.org/issues/21813 * Author: pabloh (Pablo Herrero) * Status: Open ---------------------------------------- When accessing `Method#parameters` for a method using forwarding parameters, an unexpected behavior arises: ``` def foo(*, **, &) "puts(#{(method(__method__).parameters.dig(0,1))})" # Fails! end def foo(...) "puts(#{(method(__method__).parameters.dig(0,1))})" # Works fine end ``` It's very strange that you can't access the parameters, on `eval`, using the symbols provided at `Method#parameters`. Adding `[:forward, :...]` or `[:forwarding, :...]` for those cases feels simply natural. -- https://bugs.ruby-lang.org/

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