NoMethodError: undefined method `+@' for "[^":String on Ruby 2.2

[marcotc]

Since https://github.com/sj26/rspec_junit_formatter/releases/tag/v0.5.0, I started getting this error when using rspec_junit_formatter with Ruby 2.2.10p489:

# bundle exec rspec spec/ddtrace_spec.rb
Run options: include {:focus=>true}
All examples were filtered out; ignoring {:focus=>true}
No examples found.
bundler: failed to load command: rspec (/usr/local/bundle/bin/rspec)
NoMethodError: undefined method `+@' for "[^":String
  .../rspec_junit_formatter-0.5.0/lib/rspec_junit_formatter.rb:96:in `<class:RSpecJUnitFormatter>'
  .../rspec_junit_formatter-0.5.0/lib/rspec_junit_formatter.rb:11:in `<top (required)>'
  .../rspec-core-3.10.1/lib/rspec/core/formatters.rb:235:in `require'
  .../rspec-core-3.10.1/lib/rspec/core/formatters.rb:235:in `rescue in custom_formatter'
  .../rspec-core-3.10.1/lib/rspec/core/formatters.rb:232:in `custom_formatter'
  .../rspec-core-3.10.1/lib/rspec/core/formatters.rb:183:in `find_formatter'
  .../rspec-core-3.10.1/lib/rspec/core/formatters.rb:152:in `add'
  .../rspec-core-3.10.1/lib/rspec/core/configuration.rb:974:in `add_formatter'
  .../rspec-core-3.10.1/lib/rspec/core/configuration_options.rb:118:in `block in load_formatters_into'
  .../rspec-core-3.10.1/lib/rspec/core/configuration_options.rb:118:in `each'
  .../rspec-core-3.10.1/lib/rspec/core/configuration_options.rb:118:in `load_formatters_into'
  .../rspec-core-3.10.1/lib/rspec/core/configuration_options.rb:24:in `configure'
  .../rspec-core-3.10.1/lib/rspec/core/runner.rb:132:in `configure'
  .../rspec-core-3.10.1/lib/rspec/core/runner.rb:99:in `setup'
  .../rspec-core-3.10.1/lib/rspec/core/runner.rb:86:in `run'
  .../rspec-core-3.10.1/lib/rspec/core/runner.rb:71:in `run'
  .../rspec-core-3.10.1/lib/rspec/core/runner.rb:45:in `invoke'
  .../rspec-core-3.10.1/exe/rspec:4:in `<top (required)>'

I noticed that CI only runs for Ruby 2.6+.

If the intention is to drop support for Ruby < 2.6, updating https://github.com/sj26/rspec_junit_formatter/blob/7f69b4f00127563798bb74ab19eeca3fcb5be2d4/rspec_junit_formatter.gemspec#L12 with this requirement will allow older Rubies to continue working. Today, gem install rspec_junit_formatter will happily install 0.5.0 in older Rubies, but that version will not work.

[sj26]

Ah, sorry about that! I've released v0.5.1 with 915c2a4 which should restore backwards compatibility with older rubies, and I'll restrict the supported ruby version in the gemspec for the next version.

[sj26]

I can't run older rubies in my local environment, and they don't work on GitHub Actions, so please let me know if it's all working now or not 🙏

[marcotc]

@sj26 thank you for the super fast turnaround!

Your changes look good, but they are not reflected in rubygems.org (https://rubygems.org/gems/rspec_junit_formatter/versions/0.5.1):

Did you by any chance upload an older gem build to rubygems?

[marcotc]

By the way, I test old Ruby versions with docker: docker run --rm -it ruby:2.1 /bin/sh.

For this issue, I run gem install rspec_junit_formatter inside the container.

[sj26]

Sorry I didn’t explain well: I fixed backwards compatibility and released a new version so that the gem will continue to work on old rubies, then I restricted the ruby version for future gem versions so that the same mistake doesn’t creep in. So you should be able to install the current gem version on older rubies and it should run without errors.

Thanks for the Docker tip!