Added 4.0.0 release announcement

Author: hsbt

_posts/2025-12-03-4.0.0-released.md

@@ -0,0 +1,264 @@
+---
+title: 4.0.0 Released
+layout: post
+author: Hiroshi SHIBATA
+author_email: hsbt@ruby-lang.org
+---
+
+RubyGems 4.0.0 includes features, performance, enhancements, bug fixes, security, breaking changes, deprecations and documentation and Bundler 4.0.0 includes features, performance, enhancements, bug fixes, security, breaking changes and documentation.
+
+To update to the latest RubyGems you can run:
+
+    gem update --system [--pre]
+
+To update to the latest Bundler you can run:
+
+    gem install bundler [--pre]
+    bundle update --bundler=4.0.0
+
+## RubyGems Release Notes
+
+
+### Features:
+
+* Undeprecate `Gem::Version.new(nil)`. Pull request
+  [#9086](https://github.com/ruby/rubygems/pull/9086) by tenderlove
+* Add pattern matching support to Gem::NameTuple. Pull request
+  [#9064](https://github.com/ruby/rubygems/pull/9064) by baweaver
+* Add pattern matching support to Gem::Platform. Pull request
+  [#9062](https://github.com/ruby/rubygems/pull/9062) by baweaver
+
+### Performance:
+
+* Add `MAKEFLAGS=-j` by default before compiling. Pull request
+  [#9131](https://github.com/ruby/rubygems/pull/9131) by Edouard-chin
+* Remove some memoization. Pull request
+  [#9017](https://github.com/ruby/rubygems/pull/9017) by tenderlove
+* Pull `Gem.win_platform?` out of a hot path. Pull request
+  [#8983](https://github.com/ruby/rubygems/pull/8983) by tenderlove
+* Stop trying to remove every file on extraction. Pull request
+  [#8974](https://github.com/ruby/rubygems/pull/8974) by tenderlove
+* Use `IO.copy_stream` with IO object directly. Pull request
+  [#8970](https://github.com/ruby/rubygems/pull/8970) by tenderlove
+* Pass a file size to `IO.copy_stream`. Pull request
+  [#8966](https://github.com/ruby/rubygems/pull/8966) by tenderlove
+* Use File#chmod rather than FileUtils.chmod. Pull request
+  [#8965](https://github.com/ruby/rubygems/pull/8965) by tenderlove
+
+### Enhancements:
+
+* Update all vendored libraries to latest version. Pull request
+  [#9089](https://github.com/ruby/rubygems/pull/9089) by hsbt
+* Removed unused `Gem::Deprecate`. Pull request
+  [#9090](https://github.com/ruby/rubygems/pull/9090) by hsbt
+* Add debug logging information to see the time it took to download and
+  install a gem. Pull request
+  [#9066](https://github.com/ruby/rubygems/pull/9066) by Edouard-chin
+* Fix constants in TAR to be frozen. Pull request
+  [#9041](https://github.com/ruby/rubygems/pull/9041) by tenderlove
+* Remove open-ended and prerelease dependency warnings when building gems.
+  Pull request [#9050](https://github.com/ruby/rubygems/pull/9050) by
+  jeremyevans
+* Revamp CmakeBuilder. Pull request
+  [#8753](https://github.com/ruby/rubygems/pull/8753) by cfis
+* Restrict what schemes are acceptable in the remote fetcher. Pull request
+  [#9022](https://github.com/ruby/rubygems/pull/9022) by tenderlove
+* `gem sources --prepend` and `--append` allow finer grained control of
+  sources. Pull request [#8901](https://github.com/ruby/rubygems/pull/8901)
+  by martinemde
+* Improve `gem sources --remove` output. Pull request
+  [#8909](https://github.com/ruby/rubygems/pull/8909) by deivid-rodriguez
+* Make `gem sources` output more clear. Pull request
+  [#8938](https://github.com/ruby/rubygems/pull/8938) by deivid-rodriguez
+* Don't fail if there is no makefile, simply don't do anything. Pull
+  request [#8879](https://github.com/ruby/rubygems/pull/8879) by ioquatix
+* Use IMDSv2 for S3 instance credentials. Pull request
+  [#7709](https://github.com/ruby/rubygems/pull/7709) by folbricht-stripe
+* Fix regression in presence of RVM gems. Pull request
+  [#8854](https://github.com/ruby/rubygems/pull/8854) by deivid-rodriguez
+* Restore parsing "--" as an unknown platform rather than crashing. Pull
+  request [#8846](https://github.com/ruby/rubygems/pull/8846) by
+  deivid-rodriguez
+* Installs bundler 4.0.0 as a default gem.
+
+### Bug fixes:
+
+* Fix test failure of mswin and nmake. Pull request
+  [#9135](https://github.com/ruby/rubygems/pull/9135) by hsbt
+* Respect `BUNDLE_VERSION` config at Gem::BundlerVersionFinder. Pull
+  request [#9106](https://github.com/ruby/rubygems/pull/9106) by hsbt
+* Fix "did you mean" suggestions for unknown commands. Pull request
+  [#8948](https://github.com/ruby/rubygems/pull/8948) by deivid-rodriguez
+* Fix trailing slashes not considered by `gem sources --remove`. Pull
+  request [#8939](https://github.com/ruby/rubygems/pull/8939) by
+  deivid-rodriguez
+
+### Security:
+
+* Bump up vendored URI to 1.0.4. Pull request
+  [#9031](https://github.com/ruby/rubygems/pull/9031) by hsbt
+
+### Breaking changes:
+
+* Removed deprecated `-C` option from gem build. Pull request
+  [#9088](https://github.com/ruby/rubygems/pull/9088) by hsbt
+* Removed deprecated Gem::Specification#has_rdoc, has_rdoc= and has_rdoc?.
+  Pull request [#9084](https://github.com/ruby/rubygems/pull/9084) by hsbt
+* Removed deprecated `gem query` command. Pull request
+  [#9083](https://github.com/ruby/rubygems/pull/9083) by hsbt
+* Removed deprecated Gem::DependencyInstaller#find_gems_with_sources. Pull
+  request [#9082](https://github.com/ruby/rubygems/pull/9082) by hsbt
+* Remove deprecated methods of RubyGems. Pull request
+  [#9081](https://github.com/ruby/rubygems/pull/9081) by hsbt
+* Make verification methods private. Pull request
+  [#9051](https://github.com/ruby/rubygems/pull/9051) by tenderlove
+* Deprecate `--default` option from install command. Pull request
+  [#7588](https://github.com/ruby/rubygems/pull/7588) by hsbt
+* Removed `compatibility.rb` for RG 4.0. Pull request
+  [#8899](https://github.com/ruby/rubygems/pull/8899) by hsbt
+
+### Deprecations:
+
+* Deprecate `Gem::Specification#datadir`. Pull request
+  [#8900](https://github.com/ruby/rubygems/pull/8900) by hsbt
+
+### Documentation:
+
+* Unified UPGRADING.md and extract blog.rubygems.org. Pull request
+  [#9148](https://github.com/ruby/rubygems/pull/9148) by hsbt
+* Remove italic formatting from changelog section headers. Pull request
+  [#9128](https://github.com/ruby/rubygems/pull/9128) by hsbt
+* [DOC] Fix the location of Gem::Deprecate document. Pull request
+  [#9065](https://github.com/ruby/rubygems/pull/9065) by nobu
+* Fix typo. Pull request
+  [#9012](https://github.com/ruby/rubygems/pull/9012) by etiennebarrie
+* Added document for Gem::Uninstaller. Pull request
+  [#8904](https://github.com/ruby/rubygems/pull/8904) by hsbt
+* Use mailto link in Code of Conduct. Pull request
+  [#8849](https://github.com/ruby/rubygems/pull/8849) by deivid-rodriguez
+* Update Code of Conduct email to conduct@rubygems.org. Pull request
+  [#8848](https://github.com/ruby/rubygems/pull/8848) by indirect
+
+
+## Bundler Release Notes
+
+
+### Features:
+
+  - Support bundle install --lockfile option [#9111](https://github.com/ruby/rubygems/pull/9111)
+  - Add support for lockfile in Gemfile and bundle install --no-lock [#9059](https://github.com/ruby/rubygems/pull/9059)
+  - Add `--ext=go` to `bundle gem` [#8183](https://github.com/ruby/rubygems/pull/8183)
+  - Update Bundler::CurrentRuby::ALL_RUBY_VERSIONS [#9058](https://github.com/ruby/rubygems/pull/9058)
+  - Introduce `bundle list --format=json` [#8728](https://github.com/ruby/rubygems/pull/8728)
+
+### Performance:
+
+  - Run git operations in parallel to speed things up: [#9100](https://github.com/ruby/rubygems/pull/9100)
+  - Replace instance method look up in plugin installer [#9094](https://github.com/ruby/rubygems/pull/9094)
+  - Adjust the API_REQUEST_LIMIT to make less network roundtrip [#9071](https://github.com/ruby/rubygems/pull/9071)
+
+### Enhancements:
+
+  - Make BUNDLE_LOCKFILE environment variable have precedence over lockfile method in Gemfile [#9146](https://github.com/ruby/rubygems/pull/9146)
+  - Improve banner message for the default command [#9145](https://github.com/ruby/rubygems/pull/9145)
+  - Introduce `install_or_cli_help` and use it default `bundle` command [#9136](https://github.com/ruby/rubygems/pull/9136)
+  - Add go_gem/rake_task for Go native extension gem skeleton [#9105](https://github.com/ruby/rubygems/pull/9105)
+  - Warn users that `bundle` now display the help: [#9092](https://github.com/ruby/rubygems/pull/9092)
+  - Use DidYouMean::SpellChecker for gem suggestions in Bundler [#3857](https://github.com/ruby/rubygems/pull/3857)
+  - Update all vendored libraries to latest version [#9089](https://github.com/ruby/rubygems/pull/9089)
+  - We don't need to allow some warning now [#9074](https://github.com/ruby/rubygems/pull/9074)
+  - Support to embedded Pathname [#9056](https://github.com/ruby/rubygems/pull/9056)
+  - Enforce activation of irb when running with bundle console [#9033](https://github.com/ruby/rubygems/pull/9033)
+  - Update Magnus version in Rust extension gem template [#9025](https://github.com/ruby/rubygems/pull/9025)
+  - Add checksum of gems hosted on private servers: [#9004](https://github.com/ruby/rubygems/pull/9004)
+  - Loading support on Windows [#8254](https://github.com/ruby/rubygems/pull/8254)
+  - Improve error message when the same source is specified through `gemspec` and `path` [#8460](https://github.com/ruby/rubygems/pull/8460)
+  - Raise an error in frozen mode if some registry gems have empty checksums [#8888](https://github.com/ruby/rubygems/pull/8888)
+  - Bump vendored thor to 1.4.0 [#8883](https://github.com/ruby/rubygems/pull/8883)
+  - Delay default path and global cache changes to Bundler 5 [#8867](https://github.com/ruby/rubygems/pull/8867)
+  - Fix spacing in bundle gem newgem.gemspec.tt [#8865](https://github.com/ruby/rubygems/pull/8865)
+  - Add some missing deprecation messages [#8844](https://github.com/ruby/rubygems/pull/8844)
+
+### Bug fixes:
+
+  - Fixed checksums generation issue when no source is specified [#9133](https://github.com/ruby/rubygems/pull/9133)
+  - Check for file existence before deletion from cache [#9095](https://github.com/ruby/rubygems/pull/9095)
+  - Use method_defined?(:method, false) [#9098](https://github.com/ruby/rubygems/pull/9098)
+  - Handle BUNDLER_VERSION being set to an empty string [#6928](https://github.com/ruby/rubygems/pull/6928)
+  - Fix `bundle install` when the Gemfile contains "install_if" git gems: [#8992](https://github.com/ruby/rubygems/pull/8992)
+  - Fix installation issue related to path sources and precompiled gems [#8973](https://github.com/ruby/rubygems/pull/8973)
+  - Fix outdated lockfile during `bundle lock` when source changes [#8962](https://github.com/ruby/rubygems/pull/8962)
+  - Raise error on missing version file [#8963](https://github.com/ruby/rubygems/pull/8963)
+  - Fix `bundle cache --frozen` and `bundle cache --no-prune` not printing a deprecation message [#8926](https://github.com/ruby/rubygems/pull/8926)
+  - Fix local installation incorrectly forced if there's a `vendor/cache` directory and frozen mode is set [#8925](https://github.com/ruby/rubygems/pull/8925)
+  - Fix `bundle lock --update <gem>` with `--lockfile` flag updating all gems [#8922](https://github.com/ruby/rubygems/pull/8922)
+  - Fix `bundle show --verbose` and recommend it as an alternative to `bundle show --outdated` [#8915](https://github.com/ruby/rubygems/pull/8915)
+  - Fix `bundle cache --no-all` not printing a deprecation warning [#8912](https://github.com/ruby/rubygems/pull/8912)
+  - Fix `bundle update foo` unable to update foo in an edge case [#8897](https://github.com/ruby/rubygems/pull/8897)
+  - Fix Bundler printing more flags than actually passed in verbose mode [#8914](https://github.com/ruby/rubygems/pull/8914)
+  - Fix bundler failing to install sorbet-static in truffleruby when there's no lockfile [#8872](https://github.com/ruby/rubygems/pull/8872)
+  - Cancel deprecation of `--force` flag to `bundle install` and `bundle update` [#8843](https://github.com/ruby/rubygems/pull/8843)
+
+### Security:
+
+  - Bump up vendored URI to 1.0.4 [#9031](https://github.com/ruby/rubygems/pull/9031)
+
+### Breaking changes:
+
+  - Fix triple spacing when generating lockfile [#9076](https://github.com/ruby/rubygems/pull/9076)
+  - Hide patchlevel from lockfile [#7772](https://github.com/ruby/rubygems/pull/7772)
+  - Remove `bundler_4_mode` [#9038](https://github.com/ruby/rubygems/pull/9038)
+  - Pick and add extra changes for 4.0.0 version [#9018](https://github.com/ruby/rubygems/pull/9018)
+  - Replaced Bundler::SharedHelpers.major_deprecation to feature_removed! or feature_deprecated! [#9016](https://github.com/ruby/rubygems/pull/9016)
+  - Removed legacy_check option from SpecSet#for [#9015](https://github.com/ruby/rubygems/pull/9015)
+  - Make update_requires_all_flag to settings [#9011](https://github.com/ruby/rubygems/pull/9011)
+  - Make default cli command settings [#9010](https://github.com/ruby/rubygems/pull/9010)
+  - Make global_gem_cache flag to settings [#9009](https://github.com/ruby/rubygems/pull/9009)
+  - Consolidate removal of `Bundler.rubygems.all_specs` [#9008](https://github.com/ruby/rubygems/pull/9008)
+  - Consolidate removal of `Bundler::SpecSet#-` and `Bundler::SpecSet#<<` [#9007](https://github.com/ruby/rubygems/pull/9007)
+  - Replaced Bundler.feature_flag.plugins? to Bundler.settings [#9006](https://github.com/ruby/rubygems/pull/9006)
+  - Make `bundle show --outdated` raise an error [#8980](https://github.com/ruby/rubygems/pull/8980)
+  - Make `--local-git` flag to `bundle plugin install` raise an error [#8979](https://github.com/ruby/rubygems/pull/8979)
+  - Switch `cache_all` to be `true` by default [#8975](https://github.com/ruby/rubygems/pull/8975)
+  - Completely forbid passing `--ext` to `bundle gem` without a value [#8976](https://github.com/ruby/rubygems/pull/8976)
+  - Switch `lockfile_checksums` to be `true` by default [#8981](https://github.com/ruby/rubygems/pull/8981)
+  - Make `bundle install --binstubs` raise an error [#8978](https://github.com/ruby/rubygems/pull/8978)
+  - Make `bundle remove --install` raise an error [#8977](https://github.com/ruby/rubygems/pull/8977)
+  - Remove support for multiple global sources in Gemfile & lockfile [#8968](https://github.com/ruby/rubygems/pull/8968)
+  - Remove `allow_offline_install` setting [#8969](https://github.com/ruby/rubygems/pull/8969)
+  - Completely remove `--rubocop` flag to `bundle gem`, and related configuration [#8967](https://github.com/ruby/rubygems/pull/8967)
+  - Completely remove all remembered CLI flags [#8958](https://github.com/ruby/rubygems/pull/8958)
+  - Remove implementation of `deployment`, `capistrano` and `vlad` entrypoints [#8957](https://github.com/ruby/rubygems/pull/8957)
+  - Remove deprecated `Bundler.*clean*`, and `Bundler.environment` helpers [#8924](https://github.com/ruby/rubygems/pull/8924)
+  - Remove deprecated `bundle viz` and `bundle inject` commands [#8923](https://github.com/ruby/rubygems/pull/8923)
+  - Removed to workaround for Bundler 2.2 [#8903](https://github.com/ruby/rubygems/pull/8903)
+
+### Documentation:
+
+  - Unified UPGRADING.md and extract blog.rubygems.org [#9148](https://github.com/ruby/rubygems/pull/9148)
+  - Remove italic formatting from changelog section headers [#9128](https://github.com/ruby/rubygems/pull/9128)
+  - Small clarifications to Bundler 4 upgrade docs [#8964](https://github.com/ruby/rubygems/pull/8964)
+  - Improve documentation of `bundle doctor`, `bundle plugin`, and `bundle config` [#8919](https://github.com/ruby/rubygems/pull/8919)
+  - Make sure all CLI flags and subcommands are documented [#8861](https://github.com/ruby/rubygems/pull/8861)
+  - Clarify documentation about new default gem installation directory in Bundler 4 [#8857](https://github.com/ruby/rubygems/pull/8857)
+  - Use mailto link in Code of Conduct [#8849](https://github.com/ruby/rubygems/pull/8849)
+  - Update Code of Conduct email to conduct@rubygems.org [#8848](https://github.com/ruby/rubygems/pull/8848)
+  - Add missing link to `irb` repo in DEBUGGING.md [#8842](https://github.com/ruby/rubygems/pull/8842)
+
+
+## Manual Installation
+
+To install RubyGems by hand see the [Download RubyGems][download] page.
+
+SHA256 Checksums:
+
+* rubygems-4.0.0.tgz  
+  31ee4f84cf6d06db294f998d6028835e286847c8b3fed7b9037f9b8562abdb84
+* rubygems-4.0.0.zip  
+  1fd3800c4aa945a246965ca3de89e8e21dd191ece2154526694f99f49819f1cc
+* rubygems-update-4.0.0.gem  
+  acb143e17e81d2851ecdc0d06f9362b05d4dcf288b53775b4588fe1401f8c3a6
+
+
+[download]: https://rubygems.org/pages/download
+