Rails 3.2.8 - not loading assets (development) - ruby-on-rails

Question

I have searched around and can't rectify the situation based on the responses to other similar questions. I seem to have broken the asset pipeline somehow but can't seem to figure out how.
None of my assets are being loaded at all; rails seems to just be ignoring my manifest files. When I inspect my page in firebug, only the 'non-compiled' text inside my manifest files (both js and css) is being displayed - almost as if the asset pipeline wasn't even enabled.
I deleted the contents of public/assets since I was adding a new file to the manifest which seemed to start this behavior.
Current configuration:
environments/development.rb
# Do not compress assets
config.assets.compress = false
# Expands the lines which load the assets
config.assets.debug = true
application.rb
# Enable the asset pipeline
config.assets.enabled = true
config.assets.manifest = config.root
# Add extra assets for precompiling
config.assets.precompile += ['admin.js', 'admin.css']
# Version of your assets, change this if you want to expire all your assets
config.assets.version = '1.0'

Answer 1

I had the same issue. You can still use Ruby 2.1.2, just upgrade rails to latest 3.2.x version - it's 3.2.22
Gemfile:
gem 'rails', '3.2.22'
And run:
$ bundle update rails

Answer 2

The issue was caused by using an incompatible version of ruby. I was using version 2.1.2 which lead to unusual behavior from the sprockets gem (which powers the asset pipeline). This was fixed by downgrading to ruby 1.9.3. I haven't done any experimentation for fear of breaking it again but maybe this has been addressed in later versions of sprockets. I am using sprockets 2.1.3.
See: Rails 3.2.8 Application.js and Application.css are not working as expcted

Answer 3

Always remember two things when you want to handle Rails asset pipleline:-
if you want all you newly created js/css to autoinclude in application.js/css,pls add them in...
ELSE
IF you dont wont to add in manifest file(application.js/css) then use precompile directive in yuur environment file.
config.assets.precompile=%w(custom.css,custom2.js...etc)
so make sure you have either of these...
===========for example=-=============
suppose you have new css/js file:-
custom.css inside
app/assets/stylesheets/
so you can include in
application.css
// = require 'custom'
OR
use precompile directive:-
config.assets.precompile += %w( custom.css )
and then reference it like you always do
stylesheet_link_tag "custom"
same applies for js also

Answer 4

I just spent a few hours troubleshooting this issue (in 2017!) and it turned out I just needed to remove the gem active_reload. Updating rails and ruby was having no effect for me. The thread where I found that gold is here:
https://github.com/rails/rails/issues/2715