Is includePaths supported?

[MikeiLL]

I want to be able to @import 'purecss'; from node_modules into my sass files.

OSX
CLI version: 2.3.0
Local version: 4.0.2

From what I'm digging up, adding the includePaths parameter to the call to gulp.sass(), pointed to ./node_modules should work.

function styles() {
    return (
      gulp.src(paths.styles.src)
        .pipe(sourcemaps.init())
        .pipe(wait(200))
        .pipe(sass({
                    includePaths: ['./node_modules']
                  }))
        .on("error", sass.logError)
        .pipe(postcss([autoprefixer(), cssnano()]))
        .pipe(sourcemaps.write())
        .pipe(gulp.dest(paths.styles.dest))
    );
}

I have tried all kinds of configurations, syntax specifications (for example includePaths: path.join(__dirname, 'node_modules/bootstrap/scss/bootstrap'), and many different sass import statements.

I've also tried importing three different scss libraries.

The error message is this:

Message:
    assets/styles/main.scss
Error: File to import not found or unreadable: bootstrap.
        on line 2 of assets/styles/main.scss
>> @import "bootstrap";

I can import like this:

@import '../../node_modules/purecss-sass/vendor/assets/stylesheets/_purecss';

And with IncludePaths configured like above, I can include without the node_modules prefix, like this:

@import 'purecss-sass/vendor/assets/stylesheets/_purecss';

Or with the following configuration, I can import using names only:

.pipe(sass({
         includePaths: ['./node_modules/purecss-sass/vendor/assets/stylesheets/',
            './node_modules/modularscale-sass/stylesheets/',
            './node_modules/typi/scss/'
            ]
        }
)

Is this the expected behavior, using full paths for each primary scss file? Either way, is there a place that this is documented? I'm not seeing it on the main Gulpjs site.

Thanks much.