Heroku, ZenTest and RubyGems

Question

This question is a bit like this one but its solutions don't work for me. Using RVM, just upgraded to Rails 3.1 rc6. All working surprisingly smoothly except when I attempt to deploy to a new heroku Cedar staging stack I get an error:

-----> Heroku receiving push
-----> Ruby/Rails app detected
-----> Installing dependencies using Bundler version 1.1.pre.8
       Running: bundle install --without development:test --path vendor/bundle --deployment
       Fetching dependency information from the API at http://rubygems.org/......
       Fetching dependency information from the API at http://rubygems.org/.
       Fetching git://github.com/paneq/calendar_date_select.git
       Fetching git://github.com/moiristo/deep_cloneable.git
       Fetching git://github.com/madebydna/nested_form.git
       Fetching git://github.com/ernie/ransack.git
       Installing rake (0.9.2)
       Installing RedCloth (4.2.8) with native extensions
       Installing ZenTest (4.6.1) Unfortunately, a fatal error has occurred. Please report this error to the Bundler issue tracker at https://github.com/carlhuda/bundler/issues so that we can fix it. Thanks!
       /usr/local/lib/ruby/1.9.1/rubygems/installer.rb:170:in `install': ZenTest requires RubyGems version ~> 1.8. Try 'gem update --system' to update RubyGems itself. (Gem::InstallError)
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/source.rb:92:in `block in install'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/rubygems_integration.rb:78:in `preserve_paths'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/source.rb:82:in `install'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/installer.rb:64:in `block (2 levels) in run'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/rubygems_integration.rb:93:in `with_build_args'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/installer.rb:63:in `block in run'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/installer.rb:55:in `run'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/installer.rb:12:in `install'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/cli.rb:213:in `install'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/vendor/thor/task.rb:22:in `run'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/vendor/thor/invocation.rb:118:in `invoke_task'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/vendor/thor.rb:263:in `dispatch'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/lib/bundler/vendor/thor/base.rb:386:in `start'
       from /tmp/build_1g1g96ub4uas6/vendor/bundle/ruby/1.9.1/gems/bundler-1.1.pre.8/bin/bundle:13:in `<top (required)>'
       from vendor/bundle/ruby/1.9.1/bin/bundle:19:in `load'
       from vendor/bundle/ruby/1.9.1/bin/bundle:19:in `<main>'
 !
 !     Failed to install gems via Bundler.
 !
 !     Heroku push rejected, failed to compile Ruby/rails app

I've run gem update --system, and gem pristine --all. I've put all the test gems in group(:development, :test, :cucumber) do in my gemfile and as you can see from the trace I'm running bundle install without development test. It must be a weird dependency in my Gemfile which is here: anything look off to you?

source 'http://rubygems.org'

# Rails
gem "rails", "3.1.0.rc6"

# ORM
gem 'sqlite3'
gem "sqlite3-ruby", "~> 1.3.3"

# Custom Gemsets
gem 'calendar_date_select', :git => 'git://github.com/paneq/calendar_date_select.git', :branch => 'rails3test'
gem 'client_side_validations', '3.0.5' 
gem 'cocoon'
gem 'fastercsv', :platforms => :ruby_18
gem 'formtastic', '~> 1.2.3'
gem 'gravatar_image_tag', '1.0.0.pre2'
gem 'haml'
gem 'jquery-rails'
gem 'nested_form', :git => 'git://github.com/madebydna/nested_form.git'
gem 'nokogiri'
gem 'paperclip', '~> 2.3'
gem 'rails_helpers_fix'
gem 'simple_form'
gem 'simple-tooltip'
gem 'will_paginate', '3.0.pre4'
gem "carrierwave"   
gem "ransack", :git => "git://github.com/ernie/ransack.git" 
gem "activerecord-import", ">= 0.2.8"
gem "csv_builder"
gem 'pdfkit'
gem 'wkhtmltopdf'
gem "heroku"
gem "rmagick"
gem 'aws-s3'
gem "cancan"
gem "devise"
gem 'deep_cloneable', :git => "git://github.com/moiristo/deep_cloneable.git"
gem 'bundler'
gem "activesupport"
gem "unicorn"

# Rails 3.1 - Asset Pipeline
gem 'json'
gem 'sass'
gem 'coffee-script'
gem 'uglifier'


group(:development, :test, :cucumber) do
  gem 'autotest'
  gem 'autotest-rails'
  gem 'cucumber'
  gem 'cucumber-rails'
  gem 'factory_girl'
  gem 'factory_girl_rails'
  gem 'faker'
  gem 'launchy'
  gem 'rspec'
  gem 'rspec-core',         :require => 'rspec/core'
  gem 'rspec-expectations', :require => 'rspec/expectations'
  gem 'rspec-mocks',        :require => 'rspec/mocks'
  gem 'rspec-rails'
  gem 'spork', '>= 0.9.0.rc'
  gem 'webrat'
  gem 'ZenTest'

end

Answer 1

Okey doke, even though the logs said

Running: bundle install --without development:test --path vendor/bundle --deployment

it wasn't. Running

$ heroku config:add BUNDLE_WITHOUT="development:test" --app appname

Sorted me out. I also did

git rm Gemfile.lock

and bundle install and commit before

git push staging master

which worked, phew. Thanks for your responses, anyway.

Answer 2

Apparently, this ZenTest change is incompatible. Try locking the ZenTest version by adding/changing in your Gemfile:

gem "ZenTest", "4.6.0"

Works great for me on Cedar whereas the other solutions don't.