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CSS Sass Basics (retired) Getting Started with Sass Installing and Using Sass

Posted by Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

NoMethodError: undefined method `join' for #<ConditionVariable:0x007f9812880a20> Use --trace for backtrace.

This is what I get after going to command line, accessing my project directory that contains both my index.html file and sass (.scss) file. I get the following message:

Sass is watching for changes. Press Ctrl-C to stop.
      write ./test.css
      write ./test.css.map
NoMethodError: undefined method `join' for #<ConditionVariable:0x007f9812880a20>
  Use --trace for backtrace.

Anyone know how I can watch the sass file and have it output to my new css file? Thanks!

mikes02
mikes02
Courses Plus Student 16,968 Points

From the command line are you just using sass --watch test.scss:test.css or something along those lines? from the command line type in gem list and post what version of Listen you are using as well.

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

Hi mikes, yes. I cd into my project folder and type: sass --watch test.scss:test.css

It doesn't allow me to generate new styles on test.css- wondering why that is...

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

gem list listen (2.8.3)

mikes02
mikes02
Courses Plus Student 16,968 Points

OK, so next up try running the trace as recommended, you should be able to do:

sass --watch sass:css --trace

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

got this response and I have one project directory with the two files : 1) index.html 2) main.scss

Sass is watching for changes. Press Ctrl-C to stop.
      error No such file or directory - scss
/Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `block in listen_to': undefined        method `join' for #<ConditionVariable:0x007ff652829f88> (NoMethodError)
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `each'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `listen_to'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:338:in `watch'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin.rb:108:in `method_missing'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/sass_scss.rb:370:in `watch_or_update'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/sass_scss.rb:50:in `process_result'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/base.rb:52:in `parse'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/base.rb:19:in `parse!'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/bin/sass:13:in `<top (required)>'
from /usr/bin/sass:23:in `load'
from /usr/bin/sass:23:in `<main>'
mikes02
mikes02
Courses Plus Student 16,968 Points

OK, so it looks like you don't have a sass or css directory, so your files must just be stored in the root directory, let's instead try:

sass --watch test.scss:test.css --trace

Edit: Just saw your post a second time, so your SCSS file is main.scss and not test.scss?

Have you tried running:

sass --watch main.scss:main.css

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

Making some progress- I added a new style to the test.scss ( i changed it from main.scss to test.scss) and gave the body a background color of orange. Nothing happened.

I typed in 

sass --watch test.scss:test.css --trace

again and was able to see the new style applied. I later changed the scss to include a background-color of blue just to test it out, and nothing happened. I'm guessing that I'll have to include that watch command everytime I want to see a new style applied?

I also got this response from terminal:

Sass is watching for changes. Press Ctrl-C to stop.
/Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `block in listen_to': undefined     method `join' for #<ConditionVariable:0x007f9e5d07e448> (NoMethodError)
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `each'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:402:in `listen_to'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin/compiler.rb:338:in `watch'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/plugin.rb:108:in `method_missing'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/sass_scss.rb:370:in `watch_or_update'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/sass_scss.rb:50:in `process_result'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/base.rb:52:in `parse'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/lib/sass/exec/base.rb:19:in `parse!'
from /Library/Ruby/Gems/2.0.0/gems/sass-3.4.8/bin/sass:13:in `<top (required)>'
from /usr/bin/sass:23:in `load'
from /usr/bin/sass:23:in `<main>'
mikes02
mikes02
Courses Plus Student 16,968 Points

You should be able to just remove the --trace:

sass --watch test.scss:test.css

What happens when you run that now that you have your file names updated?

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

It looks like I have to keep typing in the watch command everytime I want a new style applied on test.scss

I get this response on terminal

Sass is watching for changes. Press Ctrl-C to stop.
  write test.css
  write test.css.map
NoMethodError: undefined method `join' for #<ConditionVariable:0x007fcb4888d4f0>
  Use --trace for backtrace.
Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

per my unbridled enthusiasm, yes it worked :) thanks again! I noticed that getting rid of listen prevents me from using Jekyll as it depends on file modifications. I reinstalled Jekyll which includes "listen" and it hasn't affected my Sass in anyway.

so far so good!

mikes02
mikes02
Courses Plus Student 16,968 Points

Hi Johnny,

Sorry if I was unclear, I didn't mean for you to remove Listen completely, only meant for you to try downgrading to a previous version, in this case it was 2.7.11

Just out of curiosity, when you run gem list now what version is Listen?

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

it's currently at 2.10.11 if anything messes up, I'll be sure to install the 2.711 version of listen.

mikes02
mikes02
Courses Plus Student 16,968 Points

Glad to hear it's working, you were at 2.8.3 and now you are at 2.10.1, while downgrading can often help in cases like this, it seems that upgrading actually took care of the problem, which is great!

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

again- thanks so much for your help! learned something new about command line and gem installations :)

1 Answer

mikes02
mikes02
Courses Plus Student 16,968 Points

You shouldn't have to. I think what you are actually going to need to do in this case is downgrade your Listen gem to a previous version. If you're on a Mac you should be able to do:

sudo gem uninstall listen
sudo gem install listen --version 2.7.11

Other solutions are also available here: https://github.com/guard/listen/issues/275#issuecomment-63697308

Johnny Garces
Johnny Garces
Courses Plus Student 8,551 Points

you're a lifesaver, mikes02! i'm curious as to what listen is and how it came into my system. Did it come with a ruby installation?

anyway thank you!

mikes02
mikes02
Courses Plus Student 16,968 Points

Johnny, did that work?

As for the Listen gem: "The Listen gem listens to file modifications and notifies you about the changes." I believe it would have been installed when you installed Sass, unless it was on your system already.