"Module build failed..." in Laravel Mix

I did not change anything in app.scss, but when I run npm run watch I get the following errors:

    error  in ./resources/sass/app.scss                                                                      

Module build failed (from ./node_modules/sass-loader/lib/loader.js):                                      
Unsupported operation: Cannot extract a file path from a URI with a fragment component                    

@ ./resources/sass/app.scss 2:14-254                                                                     

    Asset      Size   Chunks             Chunk Names                                                     
/js/app.js  2.46 MiB  /js/app  [emitted]  /js/app                                                         

ERROR in ./resources/sass/app.scss                                                                        
Module build failed (from ./node_modules/css-loader/index.js):                                            
ModuleBuildError: Module build failed (from ./node_modules/sass-loader/lib/loader.js):                    

undefined                                                                                                 
      ^                                                                                                  
      Join(null, "variables"): part 0 was null, but part 1 was not.                                       
@import 'variables';                                                                                      
        ^^^^^^^^^^^                                                                                       
  stdin 2:9  root stylesheet                                                                              
      in C:\Users\TAQI VAHEED\Desktop\#Coding\resPro\resources\sass\app.scss (line 2, column 9)           
    at runLoaders (C:\Users\TAQI VAHEED\Desktop\#Coding\resPro\node_modules\webpack\lib\NormalModule.js:30
    at C:\Users\TAQI VAHEED\Desktop\#Coding\resPro\node_modules\loader-runner\lib\LoaderRunner.js:364:11  
    at C:\Users\TAQI VAHEED\Desktop\#Coding\resPro\node_modules\loader-runner\lib\LoaderRunner.js:230:18  
    at context.callback (C:\Users\TAQI VAHEED\Desktop\#Coding\resPro\node_modules\loader-runner\lib\Loader
13)

Any help appreciated.

Finally found the issue. It is related to dart-sass being used instead of node-sass with laravel-mix v4.x.x.

Turns out something related to dart-sass or laravel-mix does not work well with paths containing a '#' symbol. In your case, your app is located at C:\Users\TAQI VAHEED\Desktop\#Coding\resPro and the #Coding folder is creating the error.

Either move your app somewhere else without a '#' symbol in the path OR enable node-sass again by following the steps from laravel-mix 4.0.0 release notes:

you can manually switch back to node-sass, like so:

npm install node-sass

 

mix.sass('resources/sass/app.sass', 'public/css', {
     implementation: require('node-sass')
});