Bundler can't find gem bundler/bower - ruby

Question

Environment:
Mac OS X 10.11.3 (El Capitan)
Homebrew 0.9.5
rvm 1.26.11 (same problem occurs with rbenv)
Bundler 1.11.2
Gemfile (excerpt):
source 'https://rubygems.org'
require 'bundler/bower'
asset "jquery", "~2.1.4"`
I get this error:
bundle install
[!] There was an error parsing `Gemfile`:
cannot load such file -- bundler/bower. Bundler cannot continue.
# from /Users/nobby/becompany/website/src/website-static/Gemfile:5
# -------------------------------------------
#
> require 'bundler/bower'
#
# -------------------------------------------
My RubyGems environment is:
- RUBYGEMS VERSION: 2.5.1
- RUBY VERSION: 2.3.0 (2015-12-25 patchlevel 0) [x86_64-darwin15]
- INSTALLATION DIRECTORY: /Users/nobby/.rvm/gems/ruby-2.3.0
- USER INSTALLATION DIRECTORY: /Users/nobby/.gem/ruby/2.3.0
- RUBY EXECUTABLE: /Users/nobby/.rvm/rubies/ruby-2.3.0/bin/ruby
- EXECUTABLE DIRECTORY: /Users/nobby/.rvm/gems/ruby-2.3.0/bin
- SPEC CACHE DIRECTORY: /Users/nobby/.gem/specs
- SYSTEM CONFIGURATION DIRECTORY: /Users/nobby/.rvm/rubies/ruby-2.3.0/etc
- RUBYGEMS PLATFORMS:
- ruby
- x86_64-darwin-15
- GEM PATHS:
- /Users/nobby/.rvm/gems/ruby-2.3.0
- /Users/nobby/.rvm/gems/ruby-2.3.0#global
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- https://rubygems.org/
- SHELL PATH:
- /Users/nobby/.rvm/gems/ruby-2.3.0/bin
- /Users/nobby/.rvm/gems/ruby-2.3.0#global/bin
- /Users/nobby/.rvm/rubies/ruby-2.3.0/bin
- /Users/nobby/.rvm/bin
- /Users/nobby/src/apache/ant/apache-ant-1.9.6/bin
- /usr/local/bin
- /usr/bin
- /bin
- /usr/sbin
- /sbin
Maybe bundler is looking in the wrong gem paths? Is there a way to see which paths it is using?
It works when I manually add the dependencies to LOAD_PATH in Gemfile; maybe this helps to point me to the cause of the problem:
[ 'bundler-bower-0.0.3', 'bower-rails-0.10.0'].each do |dep|
$LOAD_PATH.unshift "/Users/nobby/.rvm/gems/ruby-2.3.0/gems/#{dep}/lib"
end

Answer 1

https://github.com/LTe/bundler-bower
You need to
gem install 'bundler-bower'
before you can require modules from it. Potentially (hopefully) bundler is clever enough to resolve dependency order if you add
gem 'bundler-bower'
to your gemfile and then install it with
bundle install
instead