enhance auto(…) to detect missing dependencies

[RubyTuesdayDONO]

i'm not sure whether this is by design or not, but it would aid troubleshooting if auto(…) could (optionally?) detect when one of its tasks has unsatisfied dependencies. although developers should certainly be careful, it would be so helpful if auto(…) were to call out something like, task 'unreachable' has unsatisfied dependency on task 'nonexistent'.

var async = require('async'); 
async.auto({ 
    unreachable: [ 'nonexistent', function(callback) { 
        console.log('this message will not appear'); 
        callback(); 
    } ] 
}, function(err,res) { 
    if(err) { 
        console.dir(err); 
        process.exit(1); 
    } else { 
        process.exit(0); 
    } 
} 

[brianmaissy]

The simple case of a nonexistent dependency should definitely be implemented, since it costs almost nothing and would solve a common programmer error. To find loops in the dependencies would also be possible, but would take some extra processing. Still not a bad idea I think.

Obviously beyond that there's nothing much we can do.

[RubyTuesdayDONO]

dependency cycles could either throw an error or be converted into equal siblings with no children … better to throw an error in my use-cases (and probably simpler), although there are applications for everything :p