doneCallback is persisted and called after other tasks with no callback

[jsocol]

We ran into this problem writing tests for Gulp tasks, but here's an example that demonstrates the problem with only Orchestrator:

'use strict';

var Orchestrator = require('orchestrator');
var orchestrator = new Orchestrator();

orchestrator.add('foo', function() {
  // Doesn't matter.
});

orchestrator.start('foo', function doneCB(err) {
  console.log('done with foo');
});

orchestrator.start('foo');

When run, the output is

$ node example.js
done with foo
done with foo

(The problem we had was using a jasmine done() call in the doneCallback, which would end up getting called multiple times, e.g.

describe('foo', function() {
  it('should do', function(done) {
    gulp.start('foo-task', function fooCB() {
      done();
    });
  });
  it('does another thing', function() {
    gulp.start('bar-task');  // fooCB gets called again, maybe, later
  });
});

)

Since Orchestrator already inherits from EventEmitter, doneCallback could be replaced with .once() and an internal event name, e.g.:

// index.js L79
this.once('::complete', lastTask);

// index.js L150
this.emit('::complete', err);

If that's something you'd be OK with, I'd be happy to open a PR.

[robrich]

Thanks for the detailed description. This is a duplicate of #15.

[jsocol]

@robrich So what's the deal with this project? Is it maintained, or is the answer to issues here "wait for Gulp 4"?

#15 is 2 years old, and closed, and references all sorts of other things that are closed (gulp#347, gulp#55) and have been for a while, but I reproduced this issue on master. I also reproduced it on gulp#master:

'use strict';

var gulp = require('gulp');

gulp.task('foo', function() {
  // Doesn't matter.
});

gulp.start('foo', function doneCB(err) {
  console.log('done with foo');
});

gulp.start('foo');

but not on gulp#4.0, because gulp lost its .start() method (which is a thing for another day).

[jsocol]

OK, I opened #72 to add that to the README so folks don't go digging here.

[robrich]

@jsocol: gulp has abandoned orchestrator, but I have not. Orchestrator is now somewhat in a state of flux. It was built for Node 0.8 and 0.10, a world which no longer exists. Do we reboot it as https://github.com/orchestrator/orchestrator/tree/develop has done? Do we call it done and let it go? I've been pondering these thoughts for quite some time, and haven't come to a good conclusion yet. What do you think?

[robrich]

It seems I may have jumped the shark with this one. Created #73 to explore it more.