bundler issue installing jekyll with Gemfile

bundler-script

#!/bin/bash

set -ex

rm -rf ~/tmp/jekyll-test
mkdir ~/tmp/jekyll-test
cd ~/tmp/jekyll-test

cat >Gemfile <<EOF
source 'https://rubygems.org'

gem 'jekyll', '~> 2.0'
EOF

bundle env

bundle install --binstubs .bundle/bin --path vendor
./.bundle/bin/jekyll -v || true
bundle update
./.bundle/bin/jekyll -v || true
bundle update
bundle update
./.bundle/bin/jekyll -v
bundle update

typescript

~$ sh ./bundler-script
+ rm -rf /home/mhw/tmp/jekyll-test
+ mkdir /home/mhw/tmp/jekyll-test
+ cd /home/mhw/tmp/jekyll-test
+ cat
+ bundle env
Bundler 1.6.3
Ruby 2.0.0 (2014-02-24 patchlevel 451) [x86_64-linux]
Rubygems 2.3.0
GEM_HOME


Gemfile
source 'https://rubygems.org'

gem 'jekyll', '~> 2.0'


Gemfile.lock
<No Gemfile.lock found>
+ bundle install --binstubs .bundle/bin --path vendor
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Installing blankslate 2.1.2.4
Installing fast-stemmer 1.0.2
Installing classifier 1.3.4
Installing colorator 0.1
Installing kramdown 1.4.0
Installing liquid 2.6.1
Installing mercenary 0.3.4
Installing posix-spawn 0.3.8
Installing yajl-ruby 1.1.0
Installing pygments.rb 0.6.0
Installing redcarpet 3.1.2
Installing safe_yaml 1.0.3
Installing parslet 1.5.0
Installing toml 0.1.1
Installing jekyll 2.1.1
Using bundler 1.6.3
Your bundle is complete!
It was installed into ./vendor
+ ./.bundle/bin/jekyll -v
/home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.1/lib/jekyll.rb:75:in `require': cannot load such file -- jekyll-coffeescript (LoadError)
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.1/lib/jekyll.rb:75:in `<top (required)>'
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.1/bin/jekyll:6:in `require'
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.1/bin/jekyll:6:in `<top (required)>'
        from ./.bundle/bin/jekyll:16:in `load'
        from ./.bundle/bin/jekyll:16:in `<main>'
+ true
+ bundle update
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Using blankslate 2.1.2.4
Using fast-stemmer 1.0.2
Using classifier 1.3.4
Using colorator 0.1
Using kramdown 1.4.0
Using liquid 2.6.1
Using mercenary 0.3.4
Using posix-spawn 0.3.8
Using yajl-ruby 1.1.0
Using pygments.rb 0.6.0
Using redcarpet 3.1.2
Using safe_yaml 1.0.3
Using parslet 1.5.0
Using toml 0.1.1
Installing jekyll 2.1.0 (was 2.1.1)
Using bundler 1.6.3
Your bundle is updated!
+ ./.bundle/bin/jekyll -v
/home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.0/lib/jekyll.rb:75:in `require': cannot load such file -- jekyll-coffeescript (LoadError)
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.0/lib/jekyll.rb:75:in `<top (required)>'
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.0/bin/jekyll:6:in `require'
        from /home/mhw/tmp/jekyll-test/vendor/ruby/2.0.0/gems/jekyll-2.1.0/bin/jekyll:6:in `<top (required)>'
        from ./.bundle/bin/jekyll:16:in `load'
        from ./.bundle/bin/jekyll:16:in `<main>'
+ true
+ bundle update
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Using blankslate 2.1.2.4
Installing timers 1.1.0
Installing celluloid 0.15.2
Using fast-stemmer 1.0.2
Using classifier 1.3.4
Using colorator 0.1
Installing ffi 1.9.3
Using kramdown 1.4.0
Installing liquid 2.5.5 (was 2.6.1)
Installing rb-fsevent 0.9.4
Installing rb-inotify 0.9.5
Installing listen 2.7.9
Using mercenary 0.3.4
Using posix-spawn 0.3.8
Using yajl-ruby 1.1.0
Installing pygments.rb 0.5.4 (was 0.6.0)
Using redcarpet 3.1.2
Using safe_yaml 1.0.3
Using parslet 1.5.0
Using toml 0.1.1
Installing jekyll 2.0.3 (was 2.1.0)
Using bundler 1.6.3
Your bundle is updated!
+ bundle update
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Using blankslate 2.1.2.4
Using timers 1.1.0
Using celluloid 0.15.2
Using fast-stemmer 1.0.2
Using classifier 1.3.4
Installing coffee-script-source 1.7.1
Installing execjs 2.2.1
Installing coffee-script 2.3.0
Using colorator 0.1
Using ffi 1.9.3
Installing jekyll-coffeescript 1.0.0
Installing sass 3.3.10
Installing jekyll-sass-converter 1.0.0
Using kramdown 1.4.0
Using liquid 2.5.5
Using rb-fsevent 0.9.4
Using rb-inotify 0.9.5
Using listen 2.7.9
Using mercenary 0.3.4
Using posix-spawn 0.3.8
Using yajl-ruby 1.1.0
Using pygments.rb 0.5.4
Using redcarpet 3.1.2
Using safe_yaml 1.0.3
Using parslet 1.5.0
Using toml 0.1.1
Using jekyll 2.0.3
Using bundler 1.6.3
Your bundle is updated!
+ ./.bundle/bin/jekyll -v
jekyll 2.0.3
+ bundle update
Fetching gem metadata from https://rubygems.org/........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Using blankslate 2.1.2.4
Using timers 1.1.0
Using celluloid 0.15.2
Using fast-stemmer 1.0.2
Using classifier 1.3.4
Using coffee-script-source 1.7.1
Using execjs 2.2.1
Using coffee-script 2.3.0
Using colorator 0.1
Using ffi 1.9.3
Using jekyll-coffeescript 1.0.0
Using sass 3.3.10
Using jekyll-sass-converter 1.0.0
Using kramdown 1.4.0
Using liquid 2.5.5
Using rb-fsevent 0.9.4
Using rb-inotify 0.9.5
Using listen 2.7.9
Using mercenary 0.3.4
Using posix-spawn 0.3.8
Using yajl-ruby 1.1.0
Using pygments.rb 0.5.4
Using redcarpet 3.1.2
Using safe_yaml 1.0.3
Using parslet 1.5.0
Using toml 0.1.1
Using jekyll 2.0.3
Using bundler 1.6.3
Your bundle is updated!
~$