@mjsalinger can you provide a concrete example of how this is not working with promises and callbacks?

Closing for now, but I'll surely give it a second look if something is broken.

This is critical for my app. Reopening. Will update with an example shortly.

@nunofgs For example, prior to this pull request, if I create a model function as follows:

model.validateScope(user, client, scope callback) { 
 // do some work
 callback(null, scope);
}

and the code in the library before this PR is

return Promise.try(this.model.validateScope, [user, client, scope]);

it would not work. Because Promise.try in the example above is expecting the function this.model.validateScope to return a Promise, and the model uses a callback, bluebird won't process it and the then will never execute.

So to make this model function work with the Promise chain, it needs to be Promisified, becoming

return Promise.try(promisify(this.model.validateScope, 3), [user, client, scope])

This PR still breaks getClient on models using promises (see this comment).

I was reading the documentation of promisify-any again and noticed two things:

• When using promisify-any with a non-native promise library, it's cleaner to tell promisify-any to actually use it. Without the call to use() promisify-any defaults to using it's own copy of bluebird (currently bluebird@2.10.0).

var Promise = require('bluebird');
var promisify = require('promisify-any').use(Promise);

This shouldn't be a huge issue since bluebird accepts any thenable, but this brings me to the second point.

• promisify() already catches synchronous exceptions, which makes the use of bluebird's Promise.try redundant.

function fn() {
 throw new Error('test');
}

Using promisify-any:

promisify(fn)().catch(console.log.bind(console));

Using bluebird:

Promise.try(fn).catch(console.log.bind(console));

Using promisify-any without bluebird's Promise.try comes with the added benefit that we don't rely on passing arguments to Promise.try, which is deprecated as of bluebird@3.0.0.

So

return Promise.try(this.model.getUserFromClient, client);

becomes

return promisify(this.model.getUserFromClient, 1)(client);

instead of

return Promise.try(promisify(this.model.getUserFromClient, 1), client);

I like this approach, I'll make the necessary changes.

Added fixes, @maxtruxa.

Looking great. I don't see any problems with merging this.

Thanks!