ActionPack 2.3.8 gem declares incompatibility with rack 1.2

ActionPack 2.3.8 is actually, really, very compatible with both rack 1.1 and 1.2. Yet it declares in its gemspec that it is compatible only with version 1.1.

This causes problems with gem activation, notably the dreaded Bundler error:

shared_helpers.rb:127:in `gem': can't activate rack (~> 1.1.0, runtime), already activated rack-1.2.0.

The patch is to change "~> 1.1.0" to "~> 1.1" in actionpack's gemspec, as follows:

  if Gem::Version.new(Gem::VERSION) >= Gem::Version.new('1.2.0') then
    s.add_runtime_dependency(%q<activesupport>, ["= 2.3.8"])
    s.add_runtime_dependency(%q<rack>, ["~> 1.1"])
  else
    s.add_dependency(%q<activesupport>, ["= 2.3.8"])
    s.add_dependency(%q<rack>, ["~> 1.1"])
  end
else
  s.add_dependency(%q<activesupport>, ["= 2.3.8"])
  s.add_dependency(%q<rack>, ["~> 1.1"])
end

This bug was reported against 2.3.5 and was incorrectly marked as invalid. There are two separate issues here: one is how to fix this problem if it comes up (which involves carefully ordering your Gemfile and is explained by Yehuda's blog post Named Gem Environments and Bundler
) and one which is that the dependency declaration for ActionPack needs to be corrected at the source.

See https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets...