No description, website, or topics provided.
Switch branches/tags
Nothing to show
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


Create virtual gem version for checking dependency.

The purpose

This dependency setting include alpha and beta version. So this setting include "0.1.0", "0.2.1", "0.3.0.rc1"

spec.add_dependency "ota42y_test_gem", "< 0.3"

And when "0.3.0" released, we can't install it because "< 0.3" does't include "0.3.0".

We already test release candidate version so "0.3.0" will work well. But we can't check until "0.3.0" released.

For example, when ota42y_dependent_test_gem depends ota42y_test_gem '< 0.3', this setting well success.

gem 'ota42y_dependent_test_gem', '0.2.0'
gem 'ota42y_test_gem', '0.2.0'

And this setting will fail because we can't resolve dependency.

gem 'ota42y_dependent_test_gem', '0.2.0' # require 'ota42y_test_gem', '< 0.3'
gem 'ota42y_test_gem', '0.3.0'

But 'ota42y_test_gem' version '0.3.0' isn't released! So rubygems exit on finding gem process and we can't check dependency.

$ bundle update ota42y_test_gem
Fetching gem metadata from
Could not find gem 'ota42y_test_gem (= 0.3.0)' in any of the gem sources listed in your Gemfile.

virtual_gem create new version gem from old version. When use virtual_gem, we can pass finding process and check dependency.

$ bundle update ota42y_test_gem
Fetching gem metadata from
Resolving dependencies...
Bundler could not find compatible versions for gem "ota42y_test_gem":
  In Gemfile:
    ota42y_test_gem (= 0.3.0)

    ota42y_dependent_test_gem (= 0.2.0) was resolved to 0.2.0, which depends on
      ota42y_test_gem (< 0.3)

Even if we create virtual_gem, bundle will fail by dependencies error. So this gem provide overwrite gem dependencies We can change ota42y_dependent_test_gem depends ota42y_test_gem '< 0.3' to '<= 0.3', so we can pass and check next dependencies.


$ gem install virtual_gem


Please write this line to your Gemfile

::VirtualGem.register_virtual_gem(name: 'ota42y_test_gem',new_version: '0.3.0', original_version: '0.2.0')

source ""

git_source(:github) {|repo_name| "{repo_name}" }

require 'bundler'

gem 'ota42y_test_gem', '0.3.0'

This code create 'ota42y_test_gem' version 0.3.0 using 0.2.0 gem. We don't release '0.3.0' yet but bundle install will success.

% bundle install
Using bundler 1.16.1
Using ota42y_test_gem 0.3.0

If you want to override gem requirement, use register_requirements_changes.

::VirtualGem.register_requirements_changes(name: 'ota42y_dependent_test_gem', version: '0.2.0', new_requirements: { 'ota42y_test_gem': ['<= 0.3'] })

'ota42y_dependent_test_gem' version '0.2.0' depends on 'ota42y_test_gem' version '< 0.3' but this method change depends on '<=0.3'.

Important notice

We check bundle install process only. So don't use virtual_gem for execute ruby script. (We don't change ::GEM_NAME::VERSION so many gem will doesn't work well.)


After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to


Bug reports and pull requests are welcome on GitHub at[USERNAME]/virtual_gem. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.


The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the VirtualGem project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.