[wip] POC for await-able Async functions #1526
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| @@ -25,6 +25,7 @@ import wrapAsync from './internal/wrapAsync' | |||
| * If you need the index, use `eachOf`. | |||
| * @param {Function} [callback] - A callback which is called when all | |||
| * `iteratee` functions have finished, or an error occurs. Invoked with (err). | |||
| * @returns {Promise} a promise, if the callback is omitted | |||
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Deliberately never returning anything from an Async function has given us the headroom to do this!
| @@ -0,0 +1,24 @@ | |||
| import noop from 'lodash/noop'; | |||
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| var supportsPromise = typeof Promise === 'function'; | |||
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A pretty crude way to detect promise support. This would be a 3.0 feature. I thinking of dropping support for non-ES2015 environments, in which case we could always return a Promise.
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👍 for dropping pre-ES2015 support in v3.
| done(err); | ||
| }); | ||
| it('should handle async functions in map', async () => { | ||
| var result = await async.map(input, asyncIdentity); |
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This is sweet! It would be cool to also test async with generators, perhaps having a generator function that initializes some data for some of the test cases
| it('should handle async functions in each', async () => { | ||
| var promise = async.each(input, asyncIdentity); | ||
| assert(typeof promise.then === 'function'); | ||
| assert(Object.getPrototypeOf(promise) === promiseProto); |
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Why not simpler?
assert(promise instanceof Promise);
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This is exciting! Looks good so far, let me know if you need help with this PR though. I could add the rest of the tests/docs. |
| if (fn === null) return; | ||
| var callFn = fn; | ||
| fn = null; | ||
| callFn.apply(this, arguments); | ||
| }; | ||
| wrapped.promise = fn.promise; |
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Should the wrapped function not return a promise instead to allow once(fn)(...args).then(...) or how do we intend this to work?
| @@ -50,5 +50,6 @@ export default function _eachOfLimit(limit) { | |||
| } | |||
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| replenish(); | |||
| return callback.promise; | |||
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I think we'll want to track whether the callback is a user defined callback or an internal promise callback and only return promiseCallback.promise if its an internal version to avoid cases where users pass us a callback with some state on it.
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Hi guys! I've just saw this PR, and I want to tell you guys I've been developing an alternative version of Currently I’ve promisified about 65% of the library functions (with their respective tests), you can see the progress here: https://github.com/DanielRamosAcosta/async-promised/blob/master/TODO.md My plans were:
But now that I’ve seen this PR, maybe we can do something together! I’ll appreciate any thoughts you share with me. |
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This branch has diverged greatly from master, I intend to re-implement this feature soon. |
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Closing in favor of #1572 |
Related to #1515
This is something I played around with over a year ago.