Higher-order functions and common patterns for asynchronous code. 

Higher-order functions and common patterns for asynchronous code

aearly

beaugunderson

caolan

megawac

hargasinski

async

- Updated lodash to squelch a security warning (#1675)

- Updated lodash to squelch a security warning (#1620)

- Updated lodash to prevent `npm audit` warnings. (#1532, #1533)

- Made `async-es` more optimized for webpack users (#1517)

- Fixed a stack overflow with large collections and a synchronous iterator (#1514)

- Various small fixes/chores (#1505, #1511, #1527, #1530)

- Added missing aliases for many methods.  Previously, you could not (e.g.) `require('async/find')` or use `async.anyLimit`. (#1483)

- Improved `queue` performance. (#1448, #1454)

- Various doc updates (#1448, #1471, #1483)

- Added `concatLimit`, the `Limit` equivalent of [`concat`](https://caolan.github.io/async/docs.html#concat) ([#1426](https://github.com/caolan/async/issues/1426), [#1430](https://github.com/caolan/async/pull/1430))

- `concat` improvements: it now preserves order, handles falsy values and the `iteratee` callback takes a variable number of arguments ([#1437](https://github.com/caolan/async/issues/1437), [#1436](https://github.com/caolan/async/pull/1436))

- Fixed an issue in `queue`  where there was a size discrepancy between `workersList().length` and `running()` ([#1428](https://github.com/caolan/async/issues/1428), [#1429](https://github.com/caolan/async/pull/1429))

- Various doc fixes ([#1422](https://github.com/caolan/async/issues/1422), [#1424](https://github.com/caolan/async/pull/1424))

- Fixed a bug preventing functions wrapped  with `timeout()` from being re-used. ([#1418](https://github.com/caolan/async/issues/1418), [#1419](https://github.com/caolan/async/issues/1419))

- Added `tryEach`, for running async functions in parallel, where you only expect one to succeed. ([#1365](https://github.com/caolan/async/issues/1365), [#687](https://github.com/caolan/async/issues/687))

- Improved performance, most notably in `parallel` and `waterfall` ([#1395](https://github.com/caolan/async/issues/1395))

- Added `queue.remove()`, for removing items in a `queue` ([#1397](https://github.com/caolan/async/issues/1397), [#1391](https://github.com/caolan/async/issues/1391))

- Fixed using `eval`, preventing Async from running in pages with Content Security Policy ([#1404](https://github.com/caolan/async/issues/1404), [#1403](https://github.com/caolan/async/issues/1403))

- Fixed errors thrown in an `asyncify`ed function's callback being caught by the underlying Promise ([#1408](https://github.com/caolan/async/issues/1408))

- Fixed timing of `queue.empty()` ([#1367](https://github.com/caolan/async/issues/1367))

- Various doc fixes ([#1314](https://github.com/caolan/async/issues/1314), [#1394](https://github.com/caolan/async/issues/1394), [#1412](https://github.com/caolan/async/issues/1412))

- Added support for ES2017 `async` functions.  Wherever you can pass a Node-style/CPS function that uses a callback, you can also pass an `async` function.  Previously, you had to wrap `async` functions with `asyncify`.  The caveat is that it will only work if `async` functions are supported natively in your environment, transpiled implementations can't be detected.  ([#1386](https://github.com/caolan/async/issues/1386), [#1390](https://github.com/caolan/async/issues/1390))

- Small doc fix ([#1392](https://github.com/caolan/async/issues/1392))

- Added `groupBy`, and the `Series`/`Limit` equivalents, analogous to [`_.groupBy`](http://lodash.com/docs#groupBy) ([#1364](https://github.com/caolan/async/issues/1364))

- Fixed `transform` bug when `callback` was not passed ([#1381](https://github.com/caolan/async/issues/1381))

- Added note about `reflect` to `parallel` docs ([#1385](https://github.com/caolan/async/issues/1385))

- Fix `auto` bug when function names collided with Array.prototype ([#1358](https://github.com/caolan/async/issues/1358))

- Improve some error messages ([#1349](https://github.com/caolan/async/issues/1349))

- Fixed an issue in `some`, `every` and `find` where processing would continue after the result was determined.

- Cleanup implementations of `some`, `every` and `find`

- Create optimized hotpath for `filter` in array case.

- Fixed a stackoverflow bug with `detect`, `some`, `every` on large inputs ([#1293](https://github.com/caolan/async/issues/1293)).

- `retry` and `retryable` now support an optional `errorFilter` function that determines if the `task` should retry on the error ([#1256](https://github.com/caolan/async/issues/1256), [#1261](https://github.com/caolan/async/issues/1261))

- Optimized array iteration in `race`, `cargo`, `queue`, and `priorityQueue` ([#1253](https://github.com/caolan/async/issues/1253))

- Added alias documentation to doc site ([#1251](https://github.com/caolan/async/issues/1251), [#1254](https://github.com/caolan/async/issues/1254))

- Added [BootStrap scrollspy](http://getbootstrap.com/javascript/#scrollspy) to docs to highlight in the sidebar the current method being viewed  ([#1289](https://github.com/caolan/async/issues/1289), [#1300](https://github.com/caolan/async/issues/1300))

- Various minor doc fixes ([#1263](https://github.com/caolan/async/issues/1263), [#1264](https://github.com/caolan/async/issues/1264), [#1271](https://github.com/caolan/async/issues/1271), [#1278](https://github.com/caolan/async/issues/1278), [#1280](https://github.com/caolan/async/issues/1280), [#1282](https://github.com/caolan/async/issues/1282), [#1302](https://github.com/caolan/async/issues/1302))

- Significantly optimized all iteration based collection methods such as `each`, `map`, `filter`, etc ([#1245](https://github.com/caolan/async/issues/1245), [#1246](https://github.com/caolan/async/issues/1246), [#1247](https://github.com/caolan/async/issues/1247)).

First and foremost, we have a slick new [site for docs](https://caolan.github.io/async/). Special thanks to [**@hargasinski**](https://github.com/hargasinski) for his work converting our old docs to `jsdoc` format and implementing the new website. Also huge ups to [**@ivanseidel**](https://github.com/ivanseidel) for designing our new logo. It was a long process for both of these tasks, but I think these changes turned out extraordinary well.

The biggest feature is modularization. You can now `require("async/series")` to only require the `series` function. Every Async library function is available this way. You still can `require("async")` to require the entire library, like you could do before.

We also provide Async as a collection of ES2015 modules. You can now `import {each} from 'async-es'` or `import waterfall from 'async-es/waterfall'`. If you are using only a few Async functions, and are using a ES bundler such as Rollup, this can significantly lower your build size.

Major thanks to [**@Kikobeats**](github.com/Kikobeats), [**@aearly**](github.com/aearly) and [**@megawac**](github.com/megawac) for doing the majority of the modularization work, as well as [**@jdalton**](github.com/jdalton) and [**@Rich-Harris**](github.com/Rich-Harris) for advisory work on the general modularization strategy.

Another one of the general themes of the 2.0 release is standardization of what an "async" function is. We are now more strictly following the node-style continuation passing style. That is, an async function is a function that:

2. The last argument is always a callback

3. The callback can accept any number of arguments

4. The first argument passed to the callback will be treated as an error result, if the argument is truthy

5. Any number of result arguments can be passed after the "error" argument

6. The callback is called once and exactly once, either on the same tick or later tick of the JavaScript event loop.

There were several cases where Async accepted some functions that did not strictly have these properties, most notably `auto`, `every`, `some`, `filter`, `reject` and `detect`.

Another theme is performance. We have eliminated internal deferrals in all cases where they make sense. For example, in `waterfall` and `auto`, there was a `setImmediate` between each task -- these deferrals have been removed. A `setImmediate` call can add up to 1ms of delay. This might not seem like a lot, but it can add up if you are using many Async functions in the course of processing a HTTP request, for example. Nearly all asynchronous functions that do I/O already have some sort of deferral built in, so the extra deferral is unnecessary. The trade-off of this change is removing our built-in stack-overflow defense. Many synchronous callback calls in series can quickly overflow the JS call stack. If you do have a function that is sometimes synchronous (calling its callback on the same tick), and are running into stack overflows, wrap it with `async.ensureAsync()`.

Another big performance win has been re-implementing `queue`, `cargo`, and `priorityQueue` with [doubly linked lists](https://en.wikipedia.org/wiki/Doubly_linked_list) instead of arrays. This has lead to queues being an order of [magnitude faster on large sets of tasks](https://github.com/caolan/async/pull/1205).

- Async is now modularized. Individual functions can be `require()`d from the main package. (`require('async/auto')`) ([#984](https://github.com/caolan/async/issues/984), [#996](https://github.com/caolan/async/issues/996))

- Async is also available as a collection of ES2015 modules in the new `async-es` package. (`import {forEachSeries} from 'async-es'`) ([#984](https://github.com/caolan/async/issues/984), [#996](https://github.com/caolan/async/issues/996))

- Added `race`, analogous to `Promise.race()`. It will run an array of async tasks in parallel and will call its callback with the result of the first task to respond. ([#568](https://github.com/caolan/async/issues/568), [#1038](https://github.com/caolan/async/issues/1038))

- Collection methods now accept ES2015 iterators.  Maps, Sets, and anything that implements the iterator spec can now be passed directly to `each`, `map`, `parallel`, etc.. ([#579](https://github.com/caolan/async/issues/579), [#839](https://github.com/caolan/async/issues/839), [#1074](https://github.com/caolan/async/issues/1074))

- Added `mapValues`, for mapping over the properties of an object and returning an object with the same keys. ([#1157](https://github.com/caolan/async/issues/1157), [#1177](https://github.com/caolan/async/issues/1177))

  "description": "Higher-order functions and common patterns for asynchronous code",

  "homepage": "https://caolan.github.io/async/",

    "url": "https://github.com/caolan/async.git"

    "url": "https://github.com/caolan/async/issues"

    "babel-plugin-add-module-exports": "^0.2.1",

    "babel-plugin-transform-es2015-modules-commonjs": "^6.26.2",

    "rollup-plugin-node-resolve": "^2.0.0",

    "coverage": "nyc npm run mocha-node-test -- --grep @nycinvalid --invert",

    "coveralls": "npm run coverage && nyc report --reporter=text-lcov | coveralls",

    "jsdoc": "jsdoc -c ./support/jsdoc/jsdoc.json && node support/jsdoc/jsdoc-fix-html.js",

    "lint": "eslint lib/ mocha_test/ perf/memory.js perf/suites.js perf/benchmark.js support/build/ support/*.js karma.conf.js",

    "mocha-node-test": "mocha mocha_test/ --compilers js:babel-core/register",

    "mocha-test": "npm run mocha-node-test && npm run mocha-browser-test",

    "test": "npm run lint && npm run mocha-node-test"

		@@ -1,2 +0,5 @@
		#v2.6.2
		# v2.6.3
		- Updated lodash to squelch a security warning (#1675)

		# v2.6.2
		- Updated lodash to squelch a security warning (#1620)
		@@ -3,0 +6,0 @@

		{
		"name": "async",
		"description": "Higher-order functions and common patterns for asynchronous code",
		"version": "2.6.2",
		"version": "2.6.3",
		"main": "dist/async.js",
		@@ -22,3 +22,3 @@ "author": "Caolan McMahon",
		"dependencies": {
		"lodash": "^4.17.11"
		"lodash": "^4.17.14"
		},
		@@ -25,0 +25,0 @@ "devDependencies": {

Improved metrics

Dependency changes