sass variables not working in yeoman webapp

Question

I scaffolded a webapp project using yeoman. After getting my sass folder structure setup I noticed that sass variables are not working. The following is my sass folder structure:

  |-styles
     |- sass
        |-base
            |-_base.scss
            |-_colors.scss
            |-_font.scss
            |-_normalize.scss
            |-_index.scss
        |-layouts
        |-modules
        |-vendors
     |- main.scss

I created an index.scss for each of the partial folder to @import all the partial files within.

@import 'normalize';
@import 'colors';
@import 'fonts';
@import 'base';

main.scss imports all the index.scss from each folder.

@import 'sass/base/index';

And when I try to use sass variable for a color value in the colors partial for example.

$main = '#B260C2';

h1 {
   color: $main;
}

It just doesn't work. However, when I remove the sass variable and just write plain css, it works fine. I'm quite new to Yeoman and gulp, so I'm not too sure what i did wrong here. Below is the default gulp file setup that comes with the webapp generator.

// generated on 2016-10-30 using generator-webapp 2.2.0
const gulp = require('gulp');
const gulpLoadPlugins = require('gulp-load-plugins');
const browserSync = require('browser-sync');
const del = require('del');
const wiredep = require('wiredep').stream;
const runSequence = require('run-sequence');

const $ = gulpLoadPlugins();
const reload = browserSync.reload;

gulp.task('styles', () => {
  return gulp.src('app/styles/*.scss')
    .pipe($.plumber())
    .pipe($.sourcemaps.init())
    .pipe($.sass.sync({
      outputStyle: 'expanded',
      precision: 10,
      includePaths: ['.']
    }).on('error', $.sass.logError))
    .pipe($.autoprefixer({browsers: ['> 1%', 'last 2 versions', 'Firefox ESR']}))
    .pipe($.sourcemaps.write())
    .pipe(gulp.dest('.tmp/styles'))
    .pipe(reload({stream: true}));
});

gulp.task('scripts', () => {
  return gulp.src('app/scripts/**/*.js')
    .pipe($.plumber())
    .pipe($.sourcemaps.init())
    .pipe($.babel())
    .pipe($.sourcemaps.write('.'))
    .pipe(gulp.dest('.tmp/scripts'))
    .pipe(reload({stream: true}));
});

function lint(files, options) {
  return gulp.src(files)
    .pipe(reload({stream: true, once: true}))
    .pipe($.eslint(options))
    .pipe($.eslint.format())
    .pipe($.if(!browserSync.active, $.eslint.failAfterError()));
}

gulp.task('lint', () => {
  return lint('app/scripts/**/*.js', {
    fix: true
  })
    .pipe(gulp.dest('app/scripts'));
});
gulp.task('lint:test', () => {
  return lint('test/spec/**/*.js', {
    fix: true,
    env: {
      mocha: true
    }
  })
    .pipe(gulp.dest('test/spec'));
});

gulp.task('html', ['styles', 'scripts'], () => {
  return gulp.src('app/*.html')
    .pipe($.useref({searchPath: ['.tmp', 'app', '.']}))
    .pipe($.if('*.js', $.uglify()))
    .pipe($.if('*.css', $.cssnano({safe: true, autoprefixer: false})))
    .pipe($.if('*.html', $.htmlmin({collapseWhitespace: true})))
    .pipe(gulp.dest('dist'));
});

gulp.task('images', () => {
  return gulp.src('app/images/**/*')
    .pipe($.cache($.imagemin()))
    .pipe(gulp.dest('dist/images'));
});

gulp.task('fonts', () => {
  return gulp.src(require('main-bower-files')('**/*.{eot,svg,ttf,woff,woff2}', function (err) {})
    .concat('app/fonts/**/*'))
    .pipe(gulp.dest('.tmp/fonts'))
    .pipe(gulp.dest('dist/fonts'));
});

gulp.task('extras', () => {
  return gulp.src([
    'app/*',
    '!app/*.html'
  ], {
    dot: true
  }).pipe(gulp.dest('dist'));
});

gulp.task('clean', del.bind(null, ['.tmp', 'dist']));

gulp.task('serve', () => {
  runSequence(['clean', 'wiredep'], ['styles', 'scripts', 'fonts'], () => {
    browserSync({
      notify: false,
      port: 9000,
      server: {
        baseDir: ['.tmp', 'app'],
        routes: {
          '/bower_components': 'bower_components'
        }
      }
    });

    gulp.watch([
      'app/*.html',
        'app/images/**/*',
      '.tmp/fonts/**/*'
    ]).on('change', reload);

    gulp.watch('app/styles/**/*.scss', ['styles']);
      gulp.watch('app/scripts/**/*.js', ['scripts']);
      gulp.watch('app/fonts/**/*', ['fonts']);
    gulp.watch('bower.json', ['wiredep', 'fonts']);
  });
});

gulp.task('serve:dist', () => {
  browserSync({
    notify: false,
    port: 9000,
    server: {
      baseDir: ['dist']
    }
  });
});

gulp.task('serve:test', ['scripts'], () => {
  browserSync({
    notify: false,
    port: 9000,
    ui: false,
    server: {
      baseDir: 'test',
      routes: {
        '/scripts': '.tmp/scripts',
        '/bower_components': 'bower_components'
      }
    }
  });

  gulp.watch('app/scripts/**/*.js', ['scripts']);
  gulp.watch(['test/spec/**/*.js', 'test/index.html']).on('change', reload);
  gulp.watch('test/spec/**/*.js', ['lint:test']);
});

// inject bower components
gulp.task('wiredep', () => {
  gulp.src('app/styles/*.scss')
    .pipe(wiredep({
      ignorePath: /^(\.\.\/)+/
    }))
    .pipe(gulp.dest('app/styles'));

  gulp.src('app/*.html')
    .pipe(wiredep({
      ignorePath: /^(\.\.\/)*\.\./
    }))
    .pipe(gulp.dest('app'));
});

gulp.task('build', ['lint', 'html', 'images', 'fonts', 'extras'], () => {
  return gulp.src('dist/**/*').pipe($.size({title: 'build', gzip: true}));
});

gulp.task('default', () => {
  runSequence(['clean', 'wiredep'], 'build');
});

Answer 1

You declare sass variable as such:

$var: value;

Not with the = sign as you pasted in your question.