Build fails to respect source and sass_dir configuration options

[chaoscommencer]

The build job will fail under the following condition:

• The 'source' option has been manually configured in _config.yml
• The 'sass:sass_dir' option has been manually configured in _config.yml
• The main style sheet imports/includes another .scss/style file from the defined sass directory

Testing has shown that the build job does not resolve the 'sass:sass_dir' relative to the 'source' as jekyll documentation dictates. Instead it attempts to resolve 'sass:sass_dir' relative to the repository root. This results in style imports not being found and errors suggesting those files don't exist, e.g.

Rendering: Source/CSS/style.scss
Pre-Render Hooks: Source/CSS/style.scss
Rendering Markup: Source/CSS/style.scss
github-pages 232 | Error: File to import not found or unreadable: SyntaxHighlighter.
Load paths: /usr/local/bundle/gems/minima-2.5.1/_sass /usr/local/bundle/gems/minima-2.5.1/_sass on line 6 

In this example 'source' is assigned Source and 'sass:sass_dir' is assigned CSS in '_config.yml'.

This error was only resolved (only for this build job--causing it to instead break local builds) by changing 'sass:sass_dir' to Source/CSS (i.e. by including the 'source' prefix in the definition of 'sass:sass_dir').

Without a fix for this, one would require two versions of the '_config.yml' file--one for local building which correctly adheres to the documented and expected behavior, and one that works only for this build job.

Reference:

• Assets > Sass/SCSS
• Sass/SCSS Options
• jekyll-sass-converter/spec/scss_converter_spec.rb#L65