Gulp 4: Run dependency task a single time

I have a gulpfile created that runs multiple tasks on build, but needs to run a clean task before everything. I would like to define the clean as a dependency of the tasks themselves, and not have to define it in the default dependencies.

This is my grunt file:

var gulp = require('gulp');

// Not all tasks need to use streams
var gulp = require('gulp');

// Not all tasks need to use streams
gulp.task('clean', function(cb) {
  setTimeout(function() {
    console.log('cleaning done');
    cb();
  }, 500);
});

gulp.task('scripts', gulp.series('clean', function(cb) {
 setTimeout(function() {
    console.log('scripts done');
    cb();
  }, 500);
})); 

gulp.task('images', gulp.series('clean', function(cb) {
 setTimeout(function() {
    console.log('images done');
    cb();
  }, 500);
})); 

gulp.task('default', gulp.parallel('scripts', 'images'));

Which outputs:

[11:25:11] Using gulpfile C:\Projects\gulp-playground\gulpfile.js
[11:25:11] Starting 'default'...
[11:25:11] Starting 'scripts'...
[11:25:11] Starting 'images'...
[11:25:11] Starting 'clean'...
[11:25:11] Starting 'clean'...
cleaning done
[11:25:11] Finished 'clean' after 503 ms
[11:25:11] Starting '<anonymous>'...
cleaning done
[11:25:11] Finished 'clean' after 504 ms
[11:25:11] Starting '<anonymous>'...
scripts done
[11:25:12] Finished '<anonymous>' after 501 ms
[11:25:12] Finished 'scripts' after 1.01 s
images done
[11:25:12] Finished '<anonymous>' after 502 ms
[11:25:12] Finished 'images' after 1.01 s
[11:25:12] Finished 'default' after 1.01 s

However my desired output is this:

[11:26:57] Using gulpfile C:\Projects\gulp-playground\gulpfile.js
[11:26:57] Starting 'default'...
[11:26:57] Starting 'clean'...
[11:26:57] Starting 'scripts'...
[11:26:57] Starting 'images'...
cleaning done
[11:26:57] Finished 'clean' after 503 ms
scripts done
[11:26:57] Finished 'scripts' after 505 ms
images done
[11:26:57] Finished 'images' after 505 ms
[11:26:57] Finished 'default' after 507 ms

I can get that by changing my gulpfile to this:

var gulp = require('gulp');

// Not all tasks need to use streams
gulp.task('clean', function(cb) {
  setTimeout(function() {
    console.log('cleaning done');
    cb();
  }, 500);
});

gulp.task('scripts', function(cb) {
 setTimeout(function() {
    console.log('scripts done');
    cb();
  }, 500);
}); 

gulp.task('images', function(cb) {
 setTimeout(function() {
    console.log('images done');
    cb();
  }, 500);
}); 

gulp.task('default', gulp.parallel('clean', 'scripts', 'images'));

However as a gulpfile grows in size and complexity, managing the dependency graph gets painfull and difficult. Is there any better way of doing this?

[phated]

No, the gulp.series/parallel paradigm is what we are going with. I spent around 1-2 months with just the concept. This stems from people having a hard time with the calculated dependency graph and gives users much more flexibility. We have added a very good --tasks CLI flag that prints your dependency graph to easy the complexity of managing the graph.

[xavierzwirtz]

Bam, there we go. Thats perfect. Thanks again.