Rails assets:precompile strange behavior

Question

I found myself in front of a strange behavior of the assets:precompile task, or at least in front of something I don't fully understand.

So, I am using Rails 3.1.3, Sprockets 2.0.3, Less 2.0.11 for my web application, plus I rely on Bootstrap for the layout, so I am using also less-rails 2.1.8 and less-rails-bootstrap 2.0.8. I have customized the style like they say here.

The configuration of my assets is:

stylesheets
|--application.css.scss
|--custom-style/
   |--variables.less
   |--mixins.less
   |--buttons.less
|--custom-style.css.less

In application.css.scss I do

//=require custom-style

And in custom-style I do

@import "twitter/bootstrap/reset";
//@import "twitter/bootstrap/variables"; // Modify this for custom colors, font-sizes, etc
@import "custom-style/variables";
//@import "twitter/bootstrap/mixins";
@import "custom-style/mixins";
// And all the other standar twitter/bootstrap imports...

// Other custom-style files to import
@import "custom-style/buttons"
//...

// And other rules here
//...

Finally in buttons.less I use some variables and mixins defined in the variables.less and mixins.less Bootstrap files, @white and .buttonBackground to be more specifc.

If I launch bundle exec rake assets:precompile with the above configuration, the task fails and I get this error:

$ bundle exec rake assets:precompile
/usr/local/rvm/rubies/ruby-1.9.3-p0/bin/ruby /usr/local/rvm/gems/ruby-1.9.3-p0/bin/rake assets:precompile:all RAILS_ENV=production RAILS_GROUPS=assets
rake aborted!
.buttonBackground is undefined

But is that if I do this changes

buttons.less --> buttons.css.less

@import "buttons"  --> @import "buttons.css.less"

Everything works fine!!

Is it something related to the scope of less variables and functions when working with nested imports? Or something that has to do with the order the less parser, or Sprockets, processes the import tree?

Am I missing something or doing something in the wrong way?

Thanks :)

Note: I get the error even with the original variables and mixins files, so it's not connected with the overrides done into them.

Answer 1

I can think of one of two possibilities right now:

1) You should change application.css.scss to application.css.less and use:

@import "custom-style";

instead of the sprockets //= require ...

2) The LESS compiler is very finicky about its semicolons. I noticed that you have @import "custom-style/buttons" - it should be @import "custom-style/buttons";

Dunno if the issue is really that simple, but it's a start.