Using Promise by default

[adriengibrat]

Hello,

I realize this is a big API breaking shift, but now promise are implemented in most browsers (but IE) and io.js, I'd expect to use it for everithing that's async.

The promise plugin is nice, but it has some drawbacks:

• It embeds a promise polyfill to 'denodify'. I would prefer to have a treo lib using promise by default, having a raw (bring you own Promise A+ implementation) and with promise polyfill in 'dist' and a plugin or utility to 'nodify' the whole API or only decorate returned promise with 'nodify' method.
• Currently, I see no simple way for plugins like 'find-in' to return promise only when expected i.e when promise plugin is included: each time someone want to use new plugin the promise plugin need to be aware of this new API method and it's arity...

If it was the other way around, Treo just have to use decorated Promise or nodify all methods (nodify does not require to know function arity).

If you like the Idea, I'll be glad to send a PR. If not, I'd like to make it live as a fork.

[alekseykulikov]

Hello Adrien,

For me treo@1.0.0 should has 3 main features: modularity, normal polyfill and promises by default. I've been experimenting with Promises+IndexedDB in free-time and faced some problems, that block future development:

• browsers have different Promise implementation, and for now only Chrome handles them right. The problem with micro tasks and IndexedDB transactions.
• default browsers c++ implementation 2-5x slower
• I implemented a idb-request module, that should help with Promise adoption, but for now quite simple test-suite only passes in Chrome, check it: https://github.com/treojs/idb-request/blob/master/test/index.js

I would like to get your help, and first steps is to pass idv-request test suite in all browsers and make sure, that we don't require 250kb bluebird to make it work properly.

What do you think?

[adriengibrat]

Hello,

• browsers have different Promise implementation, and for now only Chrome handles them right. The problem with micro tasks and IndexedDB transactions.
• default browsers c++ implementation 2-5x slower

Ok, we need is to use a Promise A+ implementation with proper microtask (any implementation using https://github.com/kriskowal/asap should work fine)

And i'ts not really a polyfill we need... I'm thinking about using 'Promise.race' to decide to use native implementation or a polyfill. If there is a bring your own Promise version, the doc need strong warning about issues with slow Promise.

• I implemented a idb-request module, that should help with Promise adoption, but for now quite simple test-suite only passes in Chrome, check it: https://github.com/treojs/idb-request/blob/master/test/index.js

I would like to get your help, and first steps is to pass idv-request test suite in all browsers and make sure, that we don't require 250kb bluebird to make it work properly.

The test suite does pass with proper polyfill I guess. I really like this bare bone implementation of Promise A+.

I'm gonna test all this with https://ci.testling.com/ to automate test in multiple browsers...

If i got it right, you're in the process of splitting treo in smaller independant projects, so what's the plan for the curent treojs repo? Making PR on this repo may not be the best way to move forward?

[alekseykulikov]

Thank you, that's a very good points.

I'm thinking about using 'Promise.race'

I think, it would be better to leave this decision to developers. So by default treo uses available global promise implementation and allows to set specific library using treo.Promise, similar to idb-request .Promise property.

The test suite does pass with proper polyfill I guess. I really like this bare bone implementation of Promise A+.

I personally, also like then/promise, but as I tested, it fails even using asap. Need to discover why. The situation with tests:

• pass in Chrome as is
• pass in Firefox with bluebird's Promise implementation
• don't run in Safari at all
• don't run in Phantomjs 1.9 with indexeddb-shim

I suppose, there're might be issues with my tests.

Making PR on this repo may not be the best way to move forward?

You are right. Let's try to make idb-request work in all supported browsers, and it will be easy to upgrade treo using it.

I'm gonna test all this with https://ci.testling.com/ to automate test in multiple browsers...

I'm not an expert, but it might be testling or zuul.

[wclr]

Aslo, if I have for example Promise polifill already loaded with other library (in my case System.js loader), hot to use it with treo, without loading installed treo's promise library dependency?

[alekseykulikov]

hey @whitecolor just wait a bit for treo@1, it will relay on Promise globally and use them by default. Or try treo@0.6.0-rc2, but it's quite experimental.

[wclr]

Ok, thanks, will be waiting!