ALT Linux Bugzilla – #43110

$ mkdir /tmp/xyz
$ cd /tmp/xyz
$ echo > Gemfile
$ pry
[1] pry(main)> require 'bundler/setup'
/usr/lib/ruby/gems/2.7.0/gems/stringio-0.1.0/lib/rubygems/source.rb:16: warning: already initialized constant Gem::Source::FILES
/usr/lib/ruby/rubygems/source.rb:16: warning: previous definition of FILES was here
Gem::LoadError: You have already activated bundler 2.2.19, but your Gemfile requires bundler 2.1.4. Prepending `bundle exec` to your command may solve this.
from /usr/lib/ruby/gems/2.7.0/gems/stringio-0.1.0/lib/bundler/runtime.rb:312:in `check_for_activated_spec!'
[2] pry(main)>

$ irb
irb(main):001:0> require 'bundler/setup'
Traceback (most recent call last):
       16: from /usr/bin/irb:23:in `load'
       15: from /usr/lib/ruby/gems/2.7.0/gems/irb-1.2.6/exe/irb:11:in `<top (required)>'
       14: from (irb):1
       13: from /usr/lib/ruby/rubygems/core_ext/kernel_require.rb:83:in `require'
       12: from /usr/lib/ruby/rubygems/core_ext/kernel_require.rb:83:in `require'
       11: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/setup.rb:10:in `<top (required)>'
       10: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/ui/shell.rb:88:in `silence'
        9: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/ui/shell.rb:136:in `with_level'
        8: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/setup.rb:10:in `block in <top (required)>'
        7: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler.rb:149:in `setup'
        6: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/runtime.rb:26:in `setup'
        5: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/runtime.rb:26:in `map'
        4: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/spec_set.rb:147:in `each'
        3: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/spec_set.rb:147:in `each'
        2: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/runtime.rb:31:in `block in setup'
        1: from /usr/lib/ruby/gems/2.7.0/gems/reline-0.1.5/lib/bundler/runtime.rb:312:in `check_for_activated_spec!'
Gem::LoadError (You have already activated bundler 2.2.19, but your Gemfile requires bundler 2.1.4. Prepending `bundle exec` to your command may solve this.)
irb(main):002:0>

$ gem list bundler -d

*** LOCAL GEMS ***

bundler (2.2.19, 2.1.4)
    Authors: André Arko, Samuel Giddins, Colby Swandale, Hiroshi
    Shibata, David Rodríguez, Grey Baker, Stephanie Morillo, Chris
    Morris, James Wen, Tim Moore, André Medeiros, Jessica Lynn Suttles,
    Terence Lee, Carl Lerche, Yehuda Katz
    Homepage: https://bundler.io
    License: MIT
    Installed at (2.2.19): /usr/lib/ruby/gems/2.7.0
                 (2.1.4): /usr/lib/ruby/gems/2.7.0

    The best way to manage your application's dependencies

При этом в чистом ruby все работет

$ ruby <<EOF
require 'bundler/setup'
EOF
$

ps. Кроме того, какие-то варнинги если запустить bundler:

$ bundler
/usr/lib/ruby/gems/2.7.0/gems/stringio-0.1.0/lib/rubygems/installer.rb:37: warning: already initialized constant Gem::Installer::ENV_PATHS
/usr/lib/ruby/rubygems/installer.rb:37: warning: previous definition of ENV_PATHS was here
/usr/lib/ruby/gems/2.7.0/gems/stringio-0.1.0/lib/rubygems/installer.rb:42: warning: already initialized constant Gem::Installer::ExtensionBuildError
/usr/lib/ruby/rubygems/installer.rb:42: warning: previous definition of ExtensionBuildError was here
The Gemfile specifies no dependencies
Bundle complete! 0 Gemfile dependencies, 1 gem now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.