text: const gulp = require('gulp');
  const zip = require('gulp-zip');
  const del = require('del');
  
  gulp.task('clean', function(done) {
      return del([
          'publish/**/*'
      ], done);
  });
  
  gulp.task('generate-manifest', function(done) {
      gulp.src(['static/images/contoso*', 'src/manifest.json'])
          .pipe(zip('TabSsoSample.zip'))
          .pipe(gulp.dest('publish'), done);
      done();
  });
  
  gulp.task('default', gulp.series('clean', 'generate-manifest'), function(done) {
      console.log('Build completed. Output in `publish` folder');
      done();
  });