Running existing task with gulp-watch

I’ve got some tasks already defined in gulpfile.js and I want to use gulp-watch plugin (to run tasks on new files). My question is, because I couldn’t find anything, can I run my existing tasks while running watch (from plugin) function?

var gulp = require('gulp'),
    watch = require('gulp-watch'),

gulp.task('lint', function () {
  return gulp.src(path.scripts)

gulp.task('watch', function () {
  watch({ glob: 'app/**/*.js' }); // Run 'lint' task for those files

Because I don’t want to include watch() task in every task I have. I would like to have only 1 task – watch, which will combine all “watches”.

—– EDIT —-
(as I probably didn’t quite get my point):

I need to run task from inside of gulp('watch') task. for example:

like I did it with

gulp.task('watch', function () {'files', ['task1', 'task2']);

I need to do the same but with gulp-watch plugin, something like (I know it wouldn’t work):

var watch = require('gulp-watch');

gulp.task('watch', function () {
  watch({ glob: 'files' }, ['task1', 'task2']);

I have also run into the problem of wanting to use gulp-watch (not, needing to use the callback form, and having trouble finding a suitable way to run a task in the callback.

My use case was that I wanted to watch all stylus files, but only process the main stylus file that includes all the others. Newer versions of gulp-watch may address this but I’m having problems with 4.3.x so I’m stuck on 4.2.5.

  • is deprecated so I don’t want to use that.
  • gulp.start works well, but is also advised against by the gulp author, contra.
  • The run-sequence plugin works well and lets you define a run
    order, but it is a self-proclaimed hack:
  • Contra suggest writing plain old functions and calling
    those. This is a new idea to me, but I think the example below captures the idea.
Read More:   Why would I use RxJS interval() or timer() polling instead of window.setInterval()?

Take your pick.

var gulp = require('gulp'),
    watch = require('gulp-watch'), // not
    runSequence = require('run-sequence');

// plain old js function
var runStylus = function() {
    return gulp.src('index.styl')
        .pipe(...) // process single file

gulp.task('stylus', runStylus);

gulp.task('watch', function() {
    // watch many files
    watch('*.styl', function() {

All of these are working for me without warnings, but I’m still unsure about getting the “done” callback from the 4.2.x version of gulp-watch.

You will most likely want to run specific tasks related to the files you are watching –

gulp.task('watch',['lint'], function () {'app/**/*.js' , ['lint']);

You can also use the ['lint'] portion to run any required tasks when watch first gets called, or utilize the tasks to run async with

gulp.task('default', ['lint','watch'])

You can just call one task, that then includes both task

gulp.task('default', ['lint','watch'])

so here you would just call ‘gulp’

gulp.task('watch', function() {
  watch(files, function() {['task1', 'task2']);

work fine, except a warning

The answers/resolutions are collected from stackoverflow, are licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 .

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