[GULP] Gulp - Cleaning Unwanted Files

Installing del Plugins

npm install del --save-dev

Declare Dependencies and Create Tasks

var del = require('del');

gulp.task('clean:build', function() {
   return del.sync('build');
});

specific file or folder

gulp.task('clean:build', function() {
   //return del.sync('build');
   return del([
      'build/temp/',
      // instructs to clean temp folder
      '!build/package.json'
      // negate to instruct not to clean package.json file ]);
});