parallel gem installation with bundler can result in a pacman locking error

[larskanis]

What problems are you experiencing?

With parallel gem installation per bundler can result in a pacman locking error. This can happen when installing multiple gems with msys2_mingw_dependencies metadata set. Parallel install is the default in all recent bundler versions.

Steps to reproduce

With the following Gemfile

source "https://rubygems.org"
gem "psych"    # requests libyaml package
gem "openssl"  # requests openssl package

and both mingw packages libyaml and openssl not yet installed, then the pacman command is executed concurrently, resulting in a locking error:

$ bundle install
Fetching gem metadata from https://rubygems.org/........
Installing psych 5.2.0 with native extensions
Installing openssl 3.2.0 with native extensions
Fehler: Der Vorgang konnte nicht gestartet werden (Kann Datenbank nicht sperren)
Fehler: Datenbank konnte nicht gesperrt werden: File exists
  Wenn Sie sicher sind, dass nicht bereits ein
  Paketmanager läuft, können Sie /var/lib/pacman/db.lck entfernen
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

current directory:
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/psych-5.2.0/ext/psych
C:/Ruby33-x64/bin/ruby.exe extconf.rb
checking for pkg-config for yaml-0.1... not found
checking for yaml.h... no
yaml.h not found
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include=${opt-dir}/include
        --without-opt-include
        --with-opt-lib=${opt-dir}/lib
        --without-opt-lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Ruby33-x64/bin/$(RUBY_BASE_NAME)
        --with-libyaml-source-dir
        --without-libyaml-source-dir
        --with-yaml-0.1-dir
        --without-yaml-0.1-dir
        --with-yaml-0.1-include=${yaml-0.1-dir}/include
        --without-yaml-0.1-include
        --with-yaml-0.1-lib=${yaml-0.1-dir}/lib
        --without-yaml-0.1-lib
        --with-yaml-0.1-config
        --without-yaml-0.1-config
        --with-pkg-config
        --without-pkg-config
        --with-libyaml-dir
        --without-libyaml-dir
        --with-libyaml-include=${libyaml-dir}/include
        --without-libyaml-include
        --with-libyaml-lib=${libyaml-dir}/lib
        --without-libyaml-lib

To see why this extension failed to compile, please check the mkmf.log which can
be found here:

C:/Ruby33-x64/lib/ruby/gems/3.3.0/extensions/x64-mingw-ucrt/3.3.0/psych-5.2.0/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/psych-5.2.0 for inspection.
Results logged to
C:/Ruby33-x64/lib/ruby/gems/3.3.0/extensions/x64-mingw-ucrt/3.3.0/psych-5.2.0/gem_make.out

  C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/builder.rb:125:in `run'
C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/ext_conf_builder.rb:28:in
`build'
C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/builder.rb:193:in
`build_extension'
C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/builder.rb:227:in `block
in build_extensions'
  C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/builder.rb:224:in `each'
C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/ext/builder.rb:224:in
`build_extensions'
C:/Ruby33-x64/lib/ruby/site_ruby/3.3.0/rubygems/installer.rb:844:in
`build_extensions'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/rubygems_gem_installer.rb:111:in
`build_extensions'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/rubygems_gem_installer.rb:30:in
`install'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/source/rubygems.rb:205:in
`install'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/installer/gem_installer.rb:55:in
`install'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/installer/gem_installer.rb:17:in
`install_from_spec'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/installer/parallel_installer.rb:133:in
`do_install'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/installer/parallel_installer.rb:124:in
`block in worker_pool'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/worker.rb:62:in
`apply_func'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/worker.rb:57:in
`block in process_queue'
  <internal:kernel>:187:in `loop'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/worker.rb:54:in
`process_queue'
C:/Ruby33-x64/lib/ruby/gems/3.3.0/gems/bundler-2.5.23/lib/bundler/worker.rb:90:in
`block (2 levels) in create_threads'

An error occurred while installing psych (5.2.0), and Bundler cannot continue.

In Gemfile:
  psych

A second attempt succeeds, since only one package is missing now:

$ bundle install
Fetching gem metadata from https://rubygems.org/........
Installing psych 5.2.0 with native extensions
Updating files in vendor/cache
Bundle complete! 2 Gemfile dependencies, 4 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.

What's the output from ridk version?

---
ruby:
  path: C:/Ruby33-x64
  version: 3.3.5
  platform: x64-mingw-ucrt
ruby_installer:
  package_version: 3.3.5-1
  git_commit: 70d8ddb
msys2:
  path: C:\Ruby33-x64\msys64
cc: gcc (Rev1, Built by MSYS2 project) 14.2.0
sh: GNU bash, Version 5.2.32(1)-release (x86_64-pc-msys)
os: Microsoft Windows [Version 10.0.22631.4317]