Fail to push to heroku - heroku

Question

Likely not the best way to migrate a rails 3 app to a rails 4 one, but I just deleted all the files (except for hidden .git files) and re-built a static webapp with no database or unit tests (rails new testapp -O --skip-bundle -T). Everything works fine on my localhost. I deleted then ran bundle install to re-create my Gemfile.lock.
I've also tested adding config.serve_static_assets = true; in config/application.rb but continue to see warning that "Detected Rails is not set to serve static_assets."
Here are the contents of my Gemfile:
source 'https://rubygems.org'
ruby '2.0.0'
#ruby-gemset=railstutorial_rails_4_0
gem 'rails', '4.0.2'
group :development do
#gem 'sqlite3', '1.3.8'
end
group :production do
gem 'rails_12factor' # for heroku
end
gem 'sass-rails', '4.0.1'
gem 'uglifier', '2.1.1'
gem 'coffee-rails', '4.0.1'
gem 'jquery-rails', '3.0.4'
gem 'turbolinks', '1.1.1'
gem 'jbuilder', '1.0.2'
group :doc do
gem 'sdoc', '0.3.20', require: false
end
And here is the output I get when trying to push to Heroku:
me-mbp:testapp me$ git push heroku master
Fetching repository, done.
Counting objects: 275, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (197/197), done.
Writing objects: 100% (211/211), 56.08 KiB | 0 bytes/s, done.
Total 211 (delta 117), reused 3 (delta 0)
-----> Ruby/Rails app detected
-----> Detected Rails is not set to serve static_assets
Installing rails3_serve_static_assets... done
-----> Configure Rails 3 to disable x-sendfile
Installing rails3_disable_x_sendfile... done
-----> Configure Rails to log to stdout
Installing rails_log_stdout... done
-----> Gemfile detected, running Bundler version 1.0.7
Unresolved dependencies detected; Installing...
Using --without development:test
/tmp/build_25e2c7af-af3f-4901-8e75-4d3e12337bf8/Gemfile:2:in `evaluate': undefined method `ruby' for #<Bundler::Dsl:0x000000025d3c78> (NoMethodError)
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/dsl.rb:7:in `instance_eval'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/dsl.rb:7:in `evaluate'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/definition.rb:17:in `build'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler.rb:128:in `definition'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/cli.rb:225:in `install'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/vendor/thor/task.rb:22:in `run'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/vendor/thor/invocation.rb:118:in `invoke_task'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/vendor/thor.rb:246:in `dispatch'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/lib/bundler/vendor/thor/base.rb:389:in `start'
from /usr/ruby1.9.2/lib/ruby/gems/1.9.1/gems/bundler-1.0.7/bin/bundle:13:in `<top (required)>'
from /usr/ruby1.9.2/bin/bundle:19:in `load'
from /usr/ruby1.9.2/bin/bundle:19:in `<main>'
FAILED: http://devcenter.heroku.com/articles/bundler
! Push failed: failed to install gems via Bundler
! If the problem persists, see http://help.heroku.com and provide Request ID 25e2c7af-af3f-4901-8e75-4d3e12337bf8.
My full Gemfile.lock file shows a higher versioned bundler and rails:
GEM
remote: https://rubygems.org/
specs:
actionmailer (4.0.2)
actionpack (= 4.0.2)
mail (~> 2.5.4)
actionpack (4.0.2)
activesupport (= 4.0.2)
builder (~> 3.1.0)
erubis (~> 2.7.0)
rack (~> 1.5.2)
rack-test (~> 0.6.2)
activemodel (4.0.2)
activesupport (= 4.0.2)
builder (~> 3.1.0)
activerecord (4.0.2)
activemodel (= 4.0.2)
activerecord-deprecated_finders (~> 1.0.2)
activesupport (= 4.0.2)
arel (~> 4.0.0)
activerecord-deprecated_finders (1.0.3)
activesupport (4.0.2)
i18n (~> 0.6, >= 0.6.4)
minitest (~> 4.2)
multi_json (~> 1.3)
thread_safe (~> 0.1)
tzinfo (~> 0.3.37)
arel (4.0.1)
atomic (1.1.14)
builder (3.1.4)
coffee-rails (4.0.1)
coffee-script (>= 2.2.0)
railties (>= 4.0.0, < 5.0)
coffee-script (2.2.0)
coffee-script-source
execjs
coffee-script-source (1.6.3)
erubis (2.7.0)
execjs (2.0.2)
hike (1.2.3)
i18n (0.6.9)
jbuilder (1.0.2)
activesupport (>= 3.0.0)
jquery-rails (3.0.4)
railties (>= 3.0, < 5.0)
thor (>= 0.14, < 2.0)
json (1.8.1)
mail (2.5.4)
mime-types (~> 1.16)
treetop (~> 1.4.8)
mime-types (1.25.1)
minitest (4.7.5)
multi_json (1.8.2)
polyglot (0.3.3)
rack (1.5.2)
rack-test (0.6.2)
rack (>= 1.0)
rails (4.0.2)
actionmailer (= 4.0.2)
actionpack (= 4.0.2)
activerecord (= 4.0.2)
activesupport (= 4.0.2)
bundler (>= 1.3.0, < 2.0)
railties (= 4.0.2)
sprockets-rails (~> 2.0.0)
rails_12factor (0.0.2)
rails_serve_static_assets
rails_stdout_logging
rails_serve_static_assets (0.0.2)
rails_stdout_logging (0.0.3)
railties (4.0.2)
actionpack (= 4.0.2)
activesupport (= 4.0.2)
rake (>= 0.8.7)
thor (>= 0.18.1, < 2.0)
rake (10.1.1)
rdoc (3.12.2)
json (~> 1.4)
sass (3.2.13)
sass-rails (4.0.1)
railties (>= 4.0.0, < 5.0)
sass (>= 3.1.10)
sprockets-rails (~> 2.0.0)
sdoc (0.3.20)
json (>= 1.1.3)
rdoc (~> 3.10)
sprockets (2.10.1)
hike (~> 1.2)
multi_json (~> 1.0)
rack (~> 1.0)
tilt (~> 1.1, != 1.3.0)
sprockets-rails (2.0.1)
actionpack (>= 3.0)
activesupport (>= 3.0)
sprockets (~> 2.8)
thor (0.18.1)
thread_safe (0.1.3)
atomic
tilt (1.4.1)
treetop (1.4.15)
polyglot
polyglot (>= 0.3.1)
turbolinks (1.1.1)
coffee-rails
tzinfo (0.3.38)
uglifier (2.1.1)
execjs (>= 0.3.0)
multi_json (~> 1.0, >= 1.0.2)
PLATFORMS
ruby
DEPENDENCIES
coffee-rails (= 4.0.1)
jbuilder (= 1.0.2)
jquery-rails (= 3.0.4)
rails (= 4.0.2)
rails_12factor
sass-rails (= 4.0.1)
sdoc (= 0.3.20)
turbolinks (= 1.1.1)
uglifier (= 2.1.1)

Answer 1

That error happens when using an old version of Bundler that doesn't support the ruby method inside the Gemfile.
This is confirmed by the deploy output
-----> Gemfile detected, running Bundler version 1.0.7
Because the Cedar stack is updated, I assume you are using the Bamboo stack. You should upgrade to Cedar.