https://travis-ci.org/thoughtbot/factory_bot_rails/jobs/567563177#L333-L355
```ruby
Bundler could not find compatible versions for gem "bundler":
In rails4.2.gemfile:
appraisal was resolved to 2.2.0, which depends on
bundler
rails (~> 4.2.11) was resolved to 4.2.11.1, which depends on
bundler (>= 1.3.0, < 2.0)
Current Bundler version:
bundler (2.0.2)
This Gemfile requires a different version of Bundler.
Perhaps you need to update Bundler by running `gem install bundler`?
Could not find gem 'bundler (>= 1.3.0, < 2.0)', which is required by gem 'rails
(~> 4.2.11)', in any of the sources.
Bundler could not find compatible versions for gem "cucumber":
In rails4.2.gemfile:
cucumber (= 1.3.19)
aruba was resolved to 0.14.11, which depends on
cucumber (>= 1.3.19)
The command "bundle install --retry 3 --jobs 8" failed and exited with 6 during .
```
because the latest version of Bundler is 2.0.2 since June 13, 2019
https://rubygems.org/gems/bundler/versions/2.0.2
Rails 4.2 requires bundler < 2.0, but on travis are getting 2.0.1
There is probably a better way to do this so we don't have to update
this every time travis starts using a new version, but I am going to
merge this for now to unblock the release of 5.0.0.rc1
Ruby 2.1 and 2.2 are no longer maintained, and Rails 3.2 and 4.2 are no
longer maintained, so I don't want to go out of our way to continue
supporting them in FactoryBot 5+. Hooray for faster test runs!
- Add Rails 5.1 and 5.2 to Appraisal
- Avoid running combinations we know are going to fail by moving to
"exclude" instead of "allow_failures"
- Use updated migration class for Rails 5.1+
* support latest Ruby 2.1
* support latest Ruby 2.2
* support latest Rails 4.2
* drop testing of Ruby 2.0
* drop testing of Rails 4.0
* fix JRuby support
* Remove gemfiles from version control to match same testing style as
Clearance and Suspenders.
* MiniTest does not need to be manually included as it is automatically
included by Rails by default.
* Add spring for Rails 4.1.
* Disable Spring to get specs to pass on Rails 4.1.
* Add therubyrhino for JRuby.
* Remove old references to Rails 3.
* Fix JRuby test where output is "1 runs", not "1 tests".
* Remove Rails 3.0 reference to "turn".
Rails 3.1.x has code which checks which version of ruby is being run,
and based on the result, selects a version of turn.
For 1.9.3+, it selects "~> 0.8.3"; for everything else, it selects "0.8.2".
If we remove turn from the Appraisals, but have travis install both versions
that rails might potentially need, the in-generated-app Gemfile building should
work correctly.
Some features test the factory_girl_rails integration with minitest-rails.
Other features just test normal integration with rails generators.
When minitest-rails is *always* in our gemfiles, minitest's generator
gets run during the features which generate new rails apps.
Because minitest doesnt support namespaced models, this fails. But, also,
we don't actually want to run minitest during anything other than the specific
areas where we are testing that integration.
Thus, we need the gem present on the system, but not in the gemfiles during
any times other than when it's pulled in specifically by those features.
