Gulp has watch method as default.

This method watches changes of specified files, and executes tasks which you want to do automatically.

Usage is below.['files you want to watch'], ['tasks you want to do'])

Let’s create task which watches the change of SCSS file and compile it by using the previous post sample.

Step 1

Fisrt, add a task to gulpfile.js.

// gulpfile.js
const gulp = require('gulp');
const sass = require('gulp-sass');

gulp.task('watch', () => {['*.scss'], ['scss']);

gulp.task('scss', () => {

Step 2

Next, execute the following command.

$ gulp watch

Step 3

Finally, let’s change style.scss.

You can find that scss task is automatically done as below.

[22:08:16] Starting 'watch'...
[22:08:16] Finished 'watch' after 14 ms
[22:08:30] Starting 'scss'...
[22:08:30] Finished 'scss' after 15 ms