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async - npm Package Compare versions

Comparing version 1.0.0 to 1.1.0

coverage/base.css
coverage/index.html
coverage/lcov-report/base.css
coverage/lcov-report/index.html
coverage/lcov-report/lib/async.js.html
coverage/lcov-report/lib/index.html
coverage/lcov-report/prettify.css
coverage/lcov-report/prettify.js
coverage/lcov-report/sort-arrow-sprite.png
coverage/lcov-report/sorter.js
coverage/lcov.info
coverage/lib/async.js.html
coverage/lib/index.html
coverage/prettify.css
coverage/prettify.js
coverage/sort-arrow-sprite.png
coverage/sorter.js
nyc_output/5999.json

24

CHANGELOG.md

@@ -0,1 +1,25 @@

# v1.1.0
New Features:
- `cargo` now supports all of the same methods and event callbacks as `queue`.
- Added `ensureAsync` - A wrapper that ensures an async function calls its callback on a later tick. (#769)
- Optimized `map`, `eachOf`, and `waterfall` families of functions
- Passing a `null` or `undefined` array to `map`, `each`, `parallel` and families will be treated as an empty array (#667).
- The callback is not optional for the composed results of `compose` and `seq`. (#618)
- Reduced file size by 4kb, (minified version by 1kb)
- Added code coverage through `nyc` and `coveralls` (#768)
Bug Fixes:
- `forever` will no longer stack overflow with a synchronous iterator (#622)
- `eachLimit` and other limit functions will stop iterating once an error occurs (#754)
- Always pass `null` in callbacks when there is no error (#439)
- Ensure proper conditions when calling `drain()` after pushing an empty data set to a queue (#668)
- `each` and family will properly handle an empty array (#578)
- `eachSeries` and family will finish if the underlying array is modified during execution (#557)
- `queue` will throw if a non-function is passed to `q.push()` (#593)
- Doc fixes (#629, #766)
# v1.0.0

@@ -2,0 +26,0 @@

931

lib/async.js

@@ -11,3 +11,3 @@ /*!

var async = {};
var noop = function () {};
function noop() {}

@@ -41,6 +41,15 @@ // global on the server, window in the browser

called = true;
fn.apply(root, arguments);
fn.apply(this, arguments);
};
}
function _once(fn) {
var called = false;
return function() {
if (called) return;
called = true;
fn.apply(this, arguments);
};
}
//// cross-browser compatiblity functions ////

@@ -54,3 +63,18 @@

var _each = function (arr, iterator) {
function _isArrayLike(arr) {
return _isArray(arr) || (
// has a positive integer length property
typeof arr.length === "number" &&
arr.length >= 0 &&
arr.length % 1 === 0
);
}
function _each(coll, iterator) {
return _isArrayLike(coll) ?
_arrayEach(coll, iterator) :
_forEachOf(coll, iterator);
}
function _arrayEach(arr, iterator) {
var index = -1,

@@ -62,5 +86,5 @@ length = arr.length;

}
};
}
var _map = function (arr, iterator) {
function _map(arr, iterator) {
var index = -1,

@@ -74,16 +98,16 @@ length = arr.length,

return result;
};
}
var _reduce = function (arr, iterator, memo) {
_each(arr, function (x, i, a) {
function _reduce(arr, iterator, memo) {
_arrayEach(arr, function (x, i, a) {
memo = iterator(memo, x, i, a);
});
return memo;
};
}
var _forEachOf = function (object, iterator) {
_each(_keys(object), function (key) {
function _forEachOf(object, iterator) {
_arrayEach(_keys(object), function (key) {
iterator(object[key], key);
});
};
}

@@ -100,3 +124,23 @@ var _keys = Object.keys || function (obj) {

var _baseSlice = function (arr, start) {
function _keyIterator(coll) {
var i = -1;
var len;
var keys;
if (_isArrayLike(coll)) {
len = coll.length;
return function next() {
i++;
return i < len ? i : null;
};
} else {
keys = _keys(coll);
len = keys.length;
return function next() {
i++;
return i < len ? keys[i] : null;
};
}
}
function _baseSlice(arr, start) {
start = start || 0;

@@ -116,4 +160,10 @@ var index = -1;

return result;
};
}
function _withoutIndex(iterator) {
return function (value, index, callback) {
return iterator(value, callback);
};
}
//// exported async module functions ////

@@ -157,152 +207,64 @@

async.forEach =
async.each = function (arr, iterator, callback) {
callback = callback || noop;
if (!arr.length) {
return callback();
}
var completed = 0;
_each(arr, function (x) {
iterator(x, only_once(done) );
});
function done(err) {
if (err) {
callback(err);
callback = noop;
}
else {
completed += 1;
if (completed >= arr.length) {
callback();
}
}
}
return async.eachOf(arr, _withoutIndex(iterator), callback);
};
async.forEach = async.each;
async.forEachSeries =
async.eachSeries = function (arr, iterator, callback) {
callback = callback || noop;
if (!arr.length) {
return callback();
}
var completed = 0;
var iterate = function () {
iterator(arr[completed], function (err) {
if (err) {
callback(err);
callback = noop;
}
else {
completed += 1;
if (completed >= arr.length) {
callback();
}
else {
iterate();
}
}
});
};
iterate();
return async.eachOfSeries(arr, _withoutIndex(iterator), callback);
};
async.forEachSeries = async.eachSeries;
async.forEachLimit =
async.eachLimit = function (arr, limit, iterator, callback) {
var fn = _eachLimit(limit);
fn.apply(null, [arr, iterator, callback]);
return _eachOfLimit(limit)(arr, _withoutIndex(iterator), callback);
};
async.forEachLimit = async.eachLimit;
var _eachLimit = function (limit) {
return function (arr, iterator, callback) {
callback = callback || noop;
if (!arr.length || limit <= 0) {
return callback();
}
var completed = 0;
var started = 0;
var running = 0;
(function replenish () {
if (completed >= arr.length) {
return callback();
}
while (running < limit && started < arr.length) {
started += 1;
running += 1;
iterator(arr[started - 1], function (err) {
if (err) {
callback(err);
callback = noop;
}
else {
completed += 1;
running -= 1;
if (completed >= arr.length) {
callback();
}
else {
replenish();
}
}
});
}
})();
};
};
async.forEachOf = async.eachOf = function (object, iterator, callback) {
callback = callback || function () {};
async.forEachOf =
async.eachOf = function (object, iterator, callback) {
callback = _once(callback || noop);
object = object || [];
var size = object.length || _keys(object).length;
var completed = 0;
if (!size) {
return callback();
return callback(null);
}
_forEachOf(object, function (value, key) {
iterator(object[key], key, function (err) {
if (err) {
callback(err);
callback = function () {};
} else {
completed += 1;
if (completed === size) {
callback(null);
}
}
});
_each(object, function (value, key) {
iterator(object[key], key, only_once(done));
});
function done(err) {
if (err) {
callback(err);
}
else {
completed += 1;
if (completed >= size) {
callback(null);
}
}
}
};
async.forEachOfSeries = async.eachOfSeries = function (obj, iterator, callback) {
callback = callback || function () {};
var keys = _keys(obj);
var size = keys.length;
if (!size) {
return callback();
}
var completed = 0;
var iterate = function () {
async.forEachOfSeries =
async.eachOfSeries = function (obj, iterator, callback) {
callback = _once(callback || noop);
obj = obj || [];
var nextKey = _keyIterator(obj);
function iterate() {
var sync = true;
var key = keys[completed];
var key = nextKey();
if (key === null) {
return callback(null);
}
iterator(obj[key], key, function (err) {
if (err) {
callback(err);
callback = function () {};
}
else {
completed += 1;
if (completed >= size) {
callback(null);
if (sync) {
async.nextTick(iterate);
}
else {
if (sync) {
async.nextTick(iterate);
}
else {
iterate();
}
iterate();
}

@@ -312,3 +274,3 @@ }

sync = false;
};
}
iterate();

@@ -319,42 +281,43 @@ };

async.forEachOfLimit = async.eachOfLimit = function (obj, limit, iterator, callback) {
_forEachOfLimit(limit)(obj, iterator, callback);
async.forEachOfLimit =
async.eachOfLimit = function (obj, limit, iterator, callback) {
_eachOfLimit(limit)(obj, iterator, callback);
};
var _forEachOfLimit = function (limit) {
function _eachOfLimit(limit) {
return function (obj, iterator, callback) {
callback = callback || function () {};
var keys = _keys(obj);
var size = keys.length;
if (!size || limit <= 0) {
return callback();
callback = _once(callback || noop);
obj = obj || [];
var nextKey = _keyIterator(obj);
if (limit <= 0) {
return callback(null);
}
var completed = 0;
var started = 0;
var done = false;
var running = 0;
var errored = false;
(function replenish () {
if (completed >= size) {
return callback();
if (done && running <= 0) {
return callback(null);
}
while (running < limit && started < size) {
started += 1;
while (running < limit && !errored) {
var key = nextKey();
if (key === null) {
done = true;
if (running <= 0) {
callback(null);
}
return;
}
running += 1;
var key = keys[started - 1];
iterator(obj[key], key, function (err) {
running -= 1;
if (err) {
callback(err);
callback = function () {};
errored = true;
}
else {
completed += 1;
running -= 1;
if (completed >= size) {
callback();
}
else {
replenish();
}
replenish();
}

@@ -365,47 +328,34 @@ });

};
};
}
var doParallel = function (fn) {
return function () {
var args = _baseSlice(arguments);
return fn.apply(null, [async.each].concat(args));
function doParallel(fn) {
return function (obj, iterator, callback) {
return fn(async.eachOf, obj, iterator, callback);
};
};
var doParallelLimit = function(limit, fn) {
return function () {
var args = _baseSlice(arguments);
return fn.apply(null, [_eachLimit(limit)].concat(args));
}
function doParallelLimit(limit, fn) {
return function (obj, iterator, callback) {
return fn(_eachOfLimit(limit), obj, iterator, callback);
};
};
var doSeries = function (fn) {
return function () {
var args = _baseSlice(arguments);
return fn.apply(null, [async.eachSeries].concat(args));
}
function doSeries(fn) {
return function (obj, iterator, callback) {
return fn(async.eachOfSeries, obj, iterator, callback);
};
};
}
function _asyncMap(eachfn, arr, iterator, callback) {
callback = _once(callback || noop);
var results = [];
eachfn(arr, function (value, index, callback) {
iterator(value, function (err, v) {
results[index] = v;
callback(err);
});
}, function (err) {
callback(err, results);
});
}
var _asyncMap = function (eachfn, arr, iterator, callback) {
arr = _map(arr, function (x, i) {
return {index: i, value: x};
});
if (!callback) {
eachfn(arr, function (x, callback) {
iterator(x.value, function (err) {
callback(err);
});
});
} else {
var results = [];
eachfn(arr, function (x, callback) {
iterator(x.value, function (err, v) {
results[x.index] = v;
callback(err);
});
}, function (err) {
callback(err, results);
});
}
};
async.map = doParallel(_asyncMap);

@@ -417,10 +367,12 @@ async.mapSeries = doSeries(_asyncMap);

var _mapLimit = function(limit) {
function _mapLimit(limit) {
return doParallelLimit(limit, _asyncMap);
};
}
// reduce only has a series version, as doing reduce in parallel won't
// work in many situations.
async.inject =
async.foldl =
async.reduce = function (arr, memo, iterator, callback) {
async.eachSeries(arr, function (x, callback) {
async.eachOfSeries(arr, function (x, i, callback) {
iterator(memo, x, function (err, v) {

@@ -431,10 +383,7 @@ memo = v;

}, function (err) {
callback(err, memo);
callback(err || null, memo);
});
};
// inject alias
async.inject = async.reduce;
// foldl alias
async.foldl = async.reduce;
async.foldr =
async.reduceRight = function (arr, memo, iterator, callback) {

@@ -446,6 +395,4 @@ var reversed = _map(arr, function (x) {

};
// foldr alias
async.foldr = async.reduceRight;
var _filter = function (eachfn, arr, iterator, callback) {
function _filter(eachfn, arr, iterator, callback) {
var results = [];

@@ -455,3 +402,3 @@ arr = _map(arr, function (x, i) {

});
eachfn(arr, function (x, callback) {
eachfn(arr, function (x, index, callback) {
iterator(x.value, function (v) {

@@ -463,3 +410,3 @@ if (v) {

});
}, function (err) {
}, function () {
callback(_map(results.sort(function (a, b) {

@@ -471,10 +418,11 @@ return a.index - b.index;

});
};
}
async.select =
async.filter = doParallel(_filter);
async.selectSeries =
async.filterSeries = doSeries(_filter);
// select alias
async.select = async.filter;
async.selectSeries = async.filterSeries;
var _reject = function (eachfn, arr, iterator, callback) {
function _reject(eachfn, arr, iterator, callback) {
var results = [];

@@ -484,3 +432,3 @@ arr = _map(arr, function (x, i) {

});
eachfn(arr, function (x, callback) {
eachfn(arr, function (x, index, callback) {
iterator(x.value, function (v) {

@@ -492,3 +440,3 @@ if (!v) {

});
}, function (err) {
}, function () {
callback(_map(results.sort(function (a, b) {

@@ -500,8 +448,8 @@ return a.index - b.index;

});
};
}
async.reject = doParallel(_reject);
async.rejectSeries = doSeries(_reject);
var _detect = function (eachfn, arr, iterator, main_callback) {
eachfn(arr, function (x, callback) {
function _detect(eachfn, arr, iterator, main_callback) {
eachfn(arr, function (x, index, callback) {
iterator(x, function (result) {

@@ -516,11 +464,12 @@ if (result) {

});
}, function (err) {
}, function () {
main_callback();
});
};
}
async.detect = doParallel(_detect);
async.detectSeries = doSeries(_detect);
async.any =
async.some = function (arr, iterator, main_callback) {
async.each(arr, function (x, callback) {
async.eachOf(arr, function (x, _, callback) {
iterator(x, function (v) {

@@ -533,11 +482,10 @@ if (v) {

});
}, function (err) {
}, function () {
main_callback(false);
});
};
// any alias
async.any = async.some;
async.all =
async.every = function (arr, iterator, main_callback) {
async.each(arr, function (x, callback) {
async.eachOf(arr, function (x, _, callback) {
iterator(x, function (v) {

@@ -550,8 +498,6 @@ if (!v) {

});
}, function (err) {
}, function () {
main_callback(true);
});
};
// all alias
async.all = async.every;

@@ -573,19 +519,21 @@ async.sortBy = function (arr, iterator, callback) {

else {
var fn = function (left, right) {
var a = left.criteria, b = right.criteria;
return a < b ? -1 : a > b ? 1 : 0;
};
callback(null, _map(results.sort(fn), function (x) {
callback(null, _map(results.sort(comparator), function (x) {
return x.value;
}));
}
});
function comparator(left, right) {
var a = left.criteria, b = right.criteria;
return a < b ? -1 : a > b ? 1 : 0;
}
};
async.auto = function (tasks, callback) {
callback = callback || noop;
callback = _once(callback || noop);
var keys = _keys(tasks);
var remainingTasks = keys.length;
if (!remainingTasks) {
return callback();
return callback(null);
}

@@ -596,6 +544,6 @@

var listeners = [];
var addListener = function (fn) {
function addListener(fn) {
listeners.unshift(fn);
};
var removeListener = function (fn) {
}
function removeListener(fn) {
for (var i = 0; i < listeners.length; i += 1) {

@@ -607,23 +555,19 @@ if (listeners[i] === fn) {

}
};
var taskComplete = function () {
}
function taskComplete() {
remainingTasks--;
_each(listeners.slice(0), function (fn) {
_arrayEach(listeners.slice(0), function (fn) {
fn();
});
};
}
addListener(function () {
if (!remainingTasks) {
var theCallback = callback;
// prevent final callback from calling itself if it errors
callback = noop;
theCallback(null, results);
callback(null, results);
}
});
_each(keys, function (k) {
_arrayEach(keys, function (k) {
var task = _isArray(tasks[k]) ? tasks[k]: [tasks[k]];
var taskCallback = function (err) {
function taskCallback(err) {
var args = _baseSlice(arguments, 1);

@@ -635,3 +579,3 @@ if (args.length <= 1) {

var safeResults = {};
_each(_keys(results), function(rkey) {
_arrayEach(_keys(results), function(rkey) {
safeResults[rkey] = results[rkey];

@@ -641,4 +585,2 @@ });

callback(err, safeResults);
// stop subsequent errors hitting callback multiple times
callback = noop;
}

@@ -649,3 +591,3 @@ else {

}
};
}
var requires = task.slice(0, Math.abs(task.length - 1)) || [];

@@ -663,7 +605,7 @@ // prevent dead-locks

}
var ready = function () {
function ready() {
return _reduce(requires, function (a, x) {
return (a && results.hasOwnProperty(x));
}, true) && !results.hasOwnProperty(k);
};
}
if (ready()) {

@@ -673,10 +615,10 @@ task[task.length - 1](taskCallback, results);

else {
var listener = function () {
if (ready()) {
removeListener(listener);
task[task.length - 1](taskCallback, results);
}
};
addListener(listener);
}
function listener() {
if (ready()) {
removeListener(listener);
task[task.length - 1](taskCallback, results);
}
}
});

@@ -696,4 +638,5 @@ };

times = parseInt(times, 10) || DEFAULT_TIMES;
var wrappedTask = function(wrappedCallback, wrappedResults) {
var retryAttempt = function(task, finalAttempt) {
function wrappedTask(wrappedCallback, wrappedResults) {
function retryAttempt(task, finalAttempt) {
return function(seriesCallback) {

@@ -704,3 +647,4 @@ task(function(err, result){

};
};
}
while (times) {

@@ -713,3 +657,4 @@ attempts.push(retryAttempt(task, !(times-=1)));

});
};
}
// If a callback is passed, run this as a controll flow

@@ -720,3 +665,3 @@ return callback ? wrappedTask() : wrappedTask;

async.waterfall = function (tasks, callback) {
callback = callback || noop;
callback = _once(callback || noop);
if (!_isArray(tasks)) {

@@ -729,7 +674,6 @@ var err = new Error('First argument to waterfall must be an array of functions');

}
var wrapIterator = function (iterator) {
function wrapIterator(iterator) {
return function (err) {
if (err) {
callback.apply(null, arguments);
callback = noop;
}

@@ -745,49 +689,33 @@ else {

}
async.setImmediate(function () {
iterator.apply(null, args);
});
ensureAsync(iterator).apply(null, args);
}
};
};
}
wrapIterator(async.iterator(tasks))();
};
var _parallel = function(eachfn, tasks, callback) {
function _parallel(eachfn, tasks, callback) {
callback = callback || noop;
if (_isArray(tasks)) {
eachfn.map(tasks, function (fn, callback) {
if (fn) {
fn(function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
callback.call(null, err, args);
});
var results = _isArrayLike(tasks) ? [] : {};
eachfn(tasks, function (task, key, callback) {
task(function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
}, callback);
}
else {
var results = {};
eachfn.each(_keys(tasks), function (k, callback) {
tasks[k](function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
results[k] = args;
callback(err);
});
}, function (err) {
callback(err, results);
results[key] = args;
callback(err);
});
}
};
}, function (err) {
callback(err, results);
});
}
async.parallel = function (tasks, callback) {
_parallel({ map: async.map, each: async.each }, tasks, callback);
_parallel(async.eachOf, tasks, callback);
};
async.parallelLimit = function(tasks, limit, callback) {
_parallel({ map: _mapLimit(limit), each: _eachLimit(limit) }, tasks, callback);
_parallel(_eachOfLimit(limit), tasks, callback);
};

@@ -797,35 +725,21 @@

callback = callback || noop;
if (_isArray(tasks)) {
async.mapSeries(tasks, function (fn, callback) {
if (fn) {
fn(function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
callback.call(null, err, args);
});
var results = _isArrayLike(tasks) ? [] : {};
async.eachOfSeries(tasks, function (task, key, callback) {
task(function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
}, callback);
}
else {
var results = {};
async.eachSeries(_keys(tasks), function (k, callback) {
tasks[k](function (err) {
var args = _baseSlice(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
results[k] = args;
callback(err);
});
}, function (err) {
callback(err, results);
results[key] = args;
callback(err);
});
}
}, function (err) {
callback(err, results);
});
};
async.iterator = function (tasks) {
var makeCallback = function (index) {
var fn = function () {
function makeCallback(index) {
function fn() {
if (tasks.length) {

@@ -835,3 +749,3 @@ tasks[index].apply(null, arguments);

return fn.next();
};
}
fn.next = function () {

@@ -841,3 +755,3 @@ return (index < tasks.length - 1) ? makeCallback(index + 1): null;

return fn;
};
}
return makeCallback(0);

@@ -855,13 +769,13 @@ };

var _concat = function (eachfn, arr, fn, callback) {
var r = [];
eachfn(arr, function (x, cb) {
function _concat(eachfn, arr, fn, callback) {
var result = [];
eachfn(arr, function (x, index, cb) {
fn(x, function (err, y) {
r = r.concat(y || []);
result = result.concat(y || []);
cb(err);
});
}, function (err) {
callback(err, r);
callback(err, result);
});
};
}
async.concat = doParallel(_concat);

@@ -880,3 +794,3 @@ async.concatSeries = doSeries(_concat);

else {
callback();
callback(null);
}

@@ -895,3 +809,3 @@ };

else {
callback();
callback(null);
}

@@ -911,3 +825,3 @@ });

else {
callback();
callback(null);
}

@@ -926,3 +840,3 @@ };

else {
callback();
callback(null);
}

@@ -932,4 +846,4 @@ });

async.queue = function (worker, concurrency) {
if (concurrency === undefined) {
function _queue(worker, concurrency, payload) {
if (concurrency == null) {
concurrency = 1;

@@ -941,33 +855,32 @@ }

function _insert(q, data, pos, callback) {
if (!q.started){
if (callback != null && typeof callback !== "function") {
throw new Error("task callback must be a function");
}
q.started = true;
}
if (!_isArray(data)) {
data = [data];
}
if(data.length === 0) {
// call drain immediately if there are no tasks
return async.setImmediate(function() {
if (q.drain) {
q.drain();
}
});
}
_each(data, function(task) {
var item = {
data: task,
callback: typeof callback === 'function' ? callback : null
};
if (!_isArray(data)) {
data = [data];
}
if(data.length === 0 && q.idle()) {
// call drain immediately if there are no tasks
return async.setImmediate(function() {
q.drain();
});
}
_arrayEach(data, function(task) {
var item = {
data: task,
callback: callback || noop
};
if (pos) {
q.tasks.unshift(item);
} else {
q.tasks.push(item);
}
if (pos) {
q.tasks.unshift(item);
} else {
q.tasks.push(item);
}
if (q.saturated && q.tasks.length === q.concurrency) {
q.saturated();
}
async.setImmediate(q.process);
});
if (q.tasks.length === q.concurrency) {
q.saturated();
}
async.setImmediate(q.process);
});
}

@@ -979,37 +892,46 @@

concurrency: concurrency,
saturated: null,
empty: null,
drain: null,
saturated: noop,
empty: noop,
drain: noop,
started: false,
paused: false,
push: function (data, callback) {
_insert(q, data, false, callback);
_insert(q, data, false, callback);
},
kill: function () {
q.drain = null;
q.tasks = [];
q.drain = noop;
q.tasks = [];
},
unshift: function (data, callback) {
_insert(q, data, true, callback);
_insert(q, data, true, callback);
},
process: function () {
if (!q.paused && workers < q.concurrency && q.tasks.length) {
var task = q.tasks.shift();
if (q.empty && q.tasks.length === 0) {
var tasks = payload ?
q.tasks.splice(0, payload) :
q.tasks.splice(0, q.tasks.length);
var data = _map(tasks, function (task) {
return task.data;
});
if (q.tasks.length === 0) {
q.empty();
}
workers += 1;
var next = function () {
workers -= 1;
if (task.callback) {
task.callback.apply(task, arguments);
}
if (q.drain && q.tasks.length + workers === 0) {
q.drain();
}
q.process();
};
var cb = only_once(next);
worker(task.data, cb);
worker(data, cb);
}
function next() {
workers -= 1;
var args = arguments;
_arrayEach(tasks, function (task) {
task.callback.apply(task, args);
});
if (q.tasks.length + workers === 0) {
q.drain();
}
q.process();
}
},

@@ -1026,3 +948,2 @@ length: function () {

pause: function () {
if (q.paused === true) { return; }
q.paused = true;

@@ -1042,2 +963,10 @@ },

return q;
}
async.queue = function (worker, concurrency) {
var q = _queue(function (items, cb) {
worker(items[0], cb);
}, concurrency, 1);
return q;
};

@@ -1048,3 +977,3 @@

function _compareTasks(a, b){
return a.priority - b.priority;
return a.priority - b.priority;
}

@@ -1056,8 +985,8 @@

while (beg < end) {
var mid = beg + ((end - beg + 1) >>> 1);
if (compare(item, sequence[mid]) >= 0) {
beg = mid;
} else {
end = mid - 1;
}
var mid = beg + ((end - beg + 1) >>> 1);
if (compare(item, sequence[mid]) >= 0) {
beg = mid;
} else {
end = mid - 1;
}
}

@@ -1068,30 +997,29 @@ return beg;

function _insert(q, data, priority, callback) {
if (!q.started){
if (callback != null && typeof callback !== "function") {
throw new Error("task callback must be a function");
}
q.started = true;
}
if (!_isArray(data)) {
data = [data];
}
if(data.length === 0) {
// call drain immediately if there are no tasks
return async.setImmediate(function() {
if (q.drain) {
q.drain();
}
});
}
_each(data, function(task) {
var item = {
data: task,
priority: priority,
callback: typeof callback === 'function' ? callback : null
};
if (!_isArray(data)) {
data = [data];
}
if(data.length === 0) {
// call drain immediately if there are no tasks
return async.setImmediate(function() {
q.drain();
});
}
_arrayEach(data, function(task) {
var item = {
data: task,
priority: priority,
callback: typeof callback === 'function' ? callback : noop
};
q.tasks.splice(_binarySearch(q.tasks, item, _compareTasks) + 1, 0, item);
q.tasks.splice(_binarySearch(q.tasks, item, _compareTasks) + 1, 0, item);
if (q.saturated && q.tasks.length === q.concurrency) {
q.saturated();
}
async.setImmediate(q.process);
});
if (q.tasks.length === q.concurrency) {
q.saturated();
}
async.setImmediate(q.process);
});
}

@@ -1104,3 +1032,3 @@

q.push = function (data, priority, callback) {
_insert(q, data, priority, callback);
_insert(q, data, priority, callback);
};

@@ -1115,70 +1043,6 @@

async.cargo = function (worker, payload) {
var working = false,
tasks = [];
var cargo = {
tasks: tasks,
payload: payload,
saturated: null,
empty: null,
drain: null,
drained: true,
push: function (data, callback) {
if (!_isArray(data)) {
data = [data];
}
_each(data, function(task) {
tasks.push({
data: task,
callback: typeof callback === 'function' ? callback : null
});
cargo.drained = false;
if (cargo.saturated && tasks.length === payload) {
cargo.saturated();
}
});
async.setImmediate(cargo.process);
},
process: function process() {
if (working) return;
if (tasks.length === 0) {
if(cargo.drain && !cargo.drained) cargo.drain();
cargo.drained = true;
return;
}
var ts = typeof payload === 'number' ?
tasks.splice(0, payload) :
tasks.splice(0, tasks.length);
var ds = _map(ts, function (task) {
return task.data;
});
if(cargo.empty) cargo.empty();
working = true;
worker(ds, function () {
working = false;
var args = arguments;
_each(ts, function (data) {
if (data.callback) {
data.callback.apply(null, args);
}
});
process();
});
},
length: function () {
return tasks.length;
},
running: function () {
return working;
}
};
return cargo;
return _queue(worker, 1, payload);
};
var _console_fn = function (name) {
function _console_fn(name) {
return function (fn) {

@@ -1195,3 +1059,3 @@ var args = _baseSlice(arguments, 1);

else if (console[name]) {
_each(args, function (x) {
_arrayEach(args, function (x) {
console[name](x);

@@ -1203,3 +1067,3 @@ });

};
};
}
async.log = _console_fn('log');

@@ -1217,3 +1081,3 @@ async.dir = _console_fn('dir');

};
var memoized = function () {
function memoized() {
var args = _baseSlice(arguments);

@@ -1241,3 +1105,3 @@ var callback = args.pop();

}
};
}
memoized.memo = memo;

@@ -1275,3 +1139,10 @@ memoized.unmemoized = fn;

var args = _baseSlice(arguments);
var callback = args.pop();
var callback = args.slice(-1)[0];
if (typeof callback == 'function') {
args.pop();
} else {
callback = noop;
}
async.reduce(fns, args, function (newargs, fn, cb) {

@@ -1294,12 +1165,13 @@ fn.apply(that, newargs.concat([function () {

var _applyEach = function (eachfn, fns /*args...*/) {
var go = function () {
function _applyEach(eachfn, fns /*args...*/) {
function go() {
var that = this;
var args = _baseSlice(arguments);
var callback = args.pop();
return eachfn(fns, function (fn, cb) {
return eachfn(fns, function (fn, _, cb) {
fn.apply(that, args.concat([cb]));
},
callback);
};
}
if (arguments.length > 2) {

@@ -1312,15 +1184,22 @@ var args = _baseSlice(arguments, 2);

}
}
async.applyEach = function (/*fns, args...*/) {
var args = _baseSlice(arguments);
return _applyEach.apply(null, [async.eachOf].concat(args));
};
async.applyEach = doParallel(_applyEach);
async.applyEachSeries = doSeries(_applyEach);
async.applyEachSeries = function (/*fns, args...*/) {
var args = _baseSlice(arguments);
return _applyEach.apply(null, [async.eachOfSeries].concat(args));
};
async.forever = function (fn, callback) {
var done = only_once(callback || noop);
var task = ensureAsync(fn);
function next(err) {
if (err) {
if (callback) {
return callback(err);
}
throw err;
return done(err);
}
fn(next);
task(next);
}

@@ -1330,2 +1209,24 @@ next();

function ensureAsync(fn) {
return function (/*...args, callback*/) {
var args = _baseSlice(arguments);
var callback = args.pop();
args.push(function () {
var innerArgs = arguments;
if (sync) {
async.setImmediate(function () {
callback.apply(null, innerArgs);
});
} else {
callback.apply(null, innerArgs);
}
});
var sync = true;
fn.apply(this, args);
sync = false;
};
}
async.ensureAsync = ensureAsync;
// Node.js

@@ -1332,0 +1233,0 @@ if (typeof module !== 'undefined' && module.exports) {

15

package.json

@@ -6,3 +6,3 @@ {

"author": "Caolan McMahon",
"version": "1.0.0",
"version": "1.1.0",
"keywords": [

@@ -23,3 +23,4 @@ "async",

"devDependencies": {
"benchmark": "~1.0.0",
"benchmark": "bestiejs/benchmark.js",
"coveralls": "^2.11.2",
"jshint": "~2.7.0",

@@ -29,3 +30,5 @@ "lodash": ">=2.4.1",

"nodeunit": ">0.0.0",
"uglify-js": "1.2.x"
"nyc": "^2.1.0",
"uglify-js": "1.2.x",
"yargs": "~3.9.1"
},

@@ -45,3 +48,5 @@ "jam": {

"test": "npm run-script lint && nodeunit test/test-async.js",
"lint": "jshint lib/*.js test/*.js perf/*.js"
"lint": "jshint lib/*.js test/*.js perf/*.js",
"coverage": "nyc npm test && nyc report",
"coveralls": "nyc npm test && nyc report --reporter=text-lcov | coveralls"
},

@@ -61,2 +66,2 @@ "spm": {

}
}
}

323

README.md

@@ -5,4 +5,4 @@ # Async.js

[![NPM version](http://img.shields.io/npm/v/async.svg)](https://www.npmjs.org/package/async)
[![Coverage Status](https://coveralls.io/repos/caolan/async/badge.svg?branch=master)](https://coveralls.io/r/caolan/async?branch=master)
Async is a utility module which provides straight-forward, powerful functions

@@ -56,2 +56,39 @@ for working with asynchronous JavaScript. Although originally designed for

<a name="stack-overflow">
### Synchronous iteration functions
If you get an error like `RangeError: Maximum call stack size exceeded.` or other stack overflow issues when using async, you are likely using a synchronous iterator. By *synchronous* we mean a function that calls its callback on the same tick in the javascript event loop, without doing any I/O or using any timers. Calling many callbacks iteratively will quickly overflow the stack. If you run into this issue, just defer your callback with `async.nextTick` to start a new call stack on the next tick of the event loop.
This can also arise by accident if you callback early in certain cases:
```js
async.eachSeries(hugeArray, function iterator(item, callback) {
if (inCache(item)) {
callback(null, cache[item]); // if many items are cached, you'll overflow
} else {
doSomeIO(item, callback);
}
}, function done() {
//...
});
```
Just change it to:
```js
async.eachSeries(hugeArray, function iterator(item, callback) {
if (inCache(item)) {
async.setImmediate(function () {
callback(null, cache[item]);
});
} else {
doSomeIO(item, callback);
//...
```
Async guards against synchronous functions in some, but not all, cases. If you are still running into stack overflows, you can defer as suggested above, or wrap functions with [`async.ensureAsync`](#ensureAsync) Functions that are asynchronous by their nature do not have this problem and don't need the extra callback deferral.
If javascript's event loop is still a bit nebulous, check out [this article](http://blog.carbonfive.com/2013/10/27/the-javascript-event-loop-explained/) or [this talk](http://2014.jsconf.eu/speakers/philip-roberts-what-the-heck-is-the-event-loop-anyway.html) for more detailed information about how it works.
### Binding a context to an iterator

@@ -67,3 +104,3 @@

squareExponent: 2,
square: function(number, callback){
square: function(number, callback){
var result = Math.pow(number, this.squareExponent);

@@ -86,3 +123,3 @@ setTimeout(function(){

// With the help of bind we can attach a context to the iterator before
// passing it to async. Now the square function will be executed in its
// passing it to async. Now the square function will be executed in its
// 'home' AsyncSquaringLibrary context and the value of `this.squareExponent`

@@ -101,3 +138,3 @@ // will be as expected.

As well as using Bower:
As well as using Bower:

@@ -110,3 +147,3 @@ bower install async

So far it's been tested in IE6, IE7, IE8, FF3.6 and Chrome 5.
So far it's been tested in IE6, IE7, IE8, FF3.6 and Chrome 5.

@@ -183,2 +220,3 @@ Usage:

* [`unmemoize`](#unmemoize)
* [`ensureAsync`](#ensureAsync)
* [`log`](#log)

@@ -193,3 +231,3 @@ * [`dir`](#dir)

<a name="each" />
### each(arr, iterator, callback)
### each(arr, iterator, [callback])

@@ -208,7 +246,7 @@ Applies the function `iterator` to each item in `arr`, in parallel.

* `iterator(item, callback)` - A function to apply to each item in `arr`.
The iterator is passed a `callback(err)` which must be called once it has
completed. If no error has occurred, the `callback` should be run without
The iterator is passed a `callback(err)` which must be called once it has
completed. If no error has occurred, the `callback` should be run without
arguments or with an explicit `null` argument. The array index is not passed
to the iterator. If you need the index, use [`forEachOf`](#forEachOf).
* `callback(err)` - A callback which is called when all `iterator` functions
* `callback(err)` - *Optional* A callback which is called when all `iterator` functions
have finished, or an error occurs.

@@ -229,9 +267,9 @@

```js
// assuming openFiles is an array of file names
// assuming openFiles is an array of file names
async.each(openFiles, function(file, callback) {
// Perform operation on file here.
console.log('Processing file ' + file);
if( file.length > 32 ) {

@@ -261,6 +299,6 @@ console.log('This file name is too long');

<a name="eachSeries" />
### eachSeries(arr, iterator, callback)
### eachSeries(arr, iterator, [callback])
The same as [`each`](#each), only `iterator` is applied to each item in `arr` in
series. The next `iterator` is only called once the current one has completed.
series. The next `iterator` is only called once the current one has completed.
This means the `iterator` functions will complete in order.

@@ -273,8 +311,8 @@

<a name="eachLimit" />
### eachLimit(arr, limit, iterator, callback)
### eachLimit(arr, limit, iterator, [callback])
The same as [`each`](#each), only no more than `limit` `iterator`s will be simultaneously
The same as [`each`](#each), only no more than `limit` `iterator`s will be simultaneously
running at any time.
Note that the items in `arr` are not processed in batches, so there is no guarantee that
Note that the items in `arr` are not processed in batches, so there is no guarantee that
the first `limit` `iterator` functions will complete before any others are started.

@@ -287,6 +325,6 @@

* `iterator(item, callback)` - A function to apply to each item in `arr`.
The iterator is passed a `callback(err)` which must be called once it has
completed. If no error has occurred, the callback should be run without
The iterator is passed a `callback(err)` which must be called once it has
completed. If no error has occurred, the callback should be run without
arguments or with an explicit `null` argument.
* `callback(err)` - A callback which is called when all `iterator` functions
* `callback(err)` - *Optional* A callback which is called when all `iterator` functions
have finished, or an error occurs.

@@ -310,3 +348,3 @@

### forEachOf(obj, iterator, callback)
### forEachOf(obj, iterator, [callback])

@@ -318,8 +356,8 @@ Like `each`, except that it iterates over objects, and passes the key as the second argument to the iterator.

* `obj` - An object or array to iterate over.
* `iterator(item, key, callback)` - A function to apply to each item in `obj`.
The `key` is the item's key, or index in the case of an array. The iterator is
* `iterator(item, key, callback)` - A function to apply to each item in `obj`.
The `key` is the item's key, or index in the case of an array. The iterator is
passed a `callback(err)` which must be called once it has completed. If no
error has occurred, the callback should be run without arguments or with an
explicit `null` argument.
* `callback(err)` - A callback which is called when all `iterator` functions have finished, or an error occurs.
* `callback(err)` - *Optional* A callback which is called when all `iterator` functions have finished, or an error occurs.

@@ -354,3 +392,3 @@ __Example__

### forEachOfSeries(obj, iterator, callback)
### forEachOfSeries(obj, iterator, [callback])

@@ -364,3 +402,3 @@ Like [`forEachOf`](#forEachOf), except only one `iterator` is run at a time. The order of execution is not guaranteed for objects, but it will be guaranteed for arrays.

### forEachOfLimit(obj, limit, iterator, callback)
### forEachOfLimit(obj, limit, iterator, [callback])

@@ -373,12 +411,12 @@ Like [`forEachOf`](#forEachOf), except the number of `iterator`s running at a given time is controlled by `limit`.

<a name="map" />
### map(arr, iterator, callback)
### map(arr, iterator, [callback])
Produces a new array of values by mapping each value in `arr` through
the `iterator` function. The `iterator` is called with an item from `arr` and a
callback for when it has finished processing. Each of these callback takes 2 arguments:
an `error`, and the transformed item from `arr`. If `iterator` passes an error to its
callback for when it has finished processing. Each of these callback takes 2 arguments:
an `error`, and the transformed item from `arr`. If `iterator` passes an error to its
callback, the main `callback` (for the `map` function) is immediately called with the error.
Note, that since this function applies the `iterator` to each item in parallel,
there is no guarantee that the `iterator` functions will complete in order.
there is no guarantee that the `iterator` functions will complete in order.
However, the results array will be in the same order as the original `arr`.

@@ -390,5 +428,5 @@

* `iterator(item, callback)` - A function to apply to each item in `arr`.
The iterator is passed a `callback(err, transformed)` which must be called once
The iterator is passed a `callback(err, transformed)` which must be called once
it has completed with an error (which can be `null`) and a transformed item.
* `callback(err, results)` - A callback which is called when all `iterator`
* `callback(err, results)` - *Optional* A callback which is called when all `iterator`
functions have finished, or an error occurs. Results is an array of the

@@ -408,6 +446,6 @@ transformed items from the `arr`.

<a name="mapSeries" />
### mapSeries(arr, iterator, callback)
### mapSeries(arr, iterator, [callback])
The same as [`map`](#map), only the `iterator` is applied to each item in `arr` in
series. The next `iterator` is only called once the current one has completed.
series. The next `iterator` is only called once the current one has completed.
The results array will be in the same order as the original.

@@ -419,8 +457,8 @@

<a name="mapLimit" />
### mapLimit(arr, limit, iterator, callback)
### mapLimit(arr, limit, iterator, [callback])
The same as [`map`](#map), only no more than `limit` `iterator`s will be simultaneously
The same as [`map`](#map), only no more than `limit` `iterator`s will be simultaneously
running at any time.
Note that the items are not processed in batches, so there is no guarantee that
Note that the items are not processed in batches, so there is no guarantee that
the first `limit` `iterator` functions will complete before any others are started.

@@ -433,3 +471,3 @@

* `iterator(item, callback)` - A function to apply to each item in `arr`.
The iterator is passed a `callback(err, transformed)` which must be called once
The iterator is passed a `callback(err, transformed)` which must be called once
it has completed with an error (which can be `null`) and a transformed item.

@@ -452,3 +490,3 @@ * `callback(err, results)` - A callback which is called when all `iterator`

<a name="filter" />
### filter(arr, iterator, callback)
### filter(arr, iterator, [callback])

@@ -468,5 +506,5 @@ __Alias:__ `select`

* `iterator(item, callback)` - A truth test to apply to each item in `arr`.
The `iterator` is passed a `callback(truthValue)`, which must be called with a
The `iterator` is passed a `callback(truthValue)`, which must be called with a
boolean argument once it has completed.
* `callback(results)` - A callback which is called after all the `iterator`
* `callback(results)` - *Optional* A callback which is called after all the `iterator`
functions have finished.

@@ -486,3 +524,3 @@

<a name="filterSeries" />
### filterSeries(arr, iterator, callback)
### filterSeries(arr, iterator, [callback])

@@ -492,3 +530,3 @@ __Alias:__ `selectSeries`

The same as [`filter`](#filter) only the `iterator` is applied to each item in `arr` in
series. The next `iterator` is only called once the current one has completed.
series. The next `iterator` is only called once the current one has completed.
The results array will be in the same order as the original.

@@ -499,3 +537,3 @@

<a name="reject" />
### reject(arr, iterator, callback)
### reject(arr, iterator, [callback])

@@ -507,3 +545,3 @@ The opposite of [`filter`](#filter). Removes values that pass an `async` truth test.

<a name="rejectSeries" />
### rejectSeries(arr, iterator, callback)
### rejectSeries(arr, iterator, [callback])

@@ -517,3 +555,3 @@ The same as [`reject`](#reject), only the `iterator` is applied to each item in `arr`

<a name="reduce" />
### reduce(arr, memo, iterator, callback)
### reduce(arr, memo, iterator, [callback])

@@ -523,8 +561,8 @@ __Aliases:__ `inject`, `foldl`

Reduces `arr` into a single value using an async `iterator` to return
each successive step. `memo` is the initial state of the reduction.
This function only operates in series.
each successive step. `memo` is the initial state of the reduction.
This function only operates in series.
For performance reasons, it may make sense to split a call to this function into
a parallel map, and then use the normal `Array.prototype.reduce` on the results.
This function is for situations where each step in the reduction needs to be async;
For performance reasons, it may make sense to split a call to this function into
a parallel map, and then use the normal `Array.prototype.reduce` on the results.
This function is for situations where each step in the reduction needs to be async;
if you can get the data before reducing it, then it's probably a good idea to do so.

@@ -538,7 +576,7 @@

array to produce the next step in the reduction. The `iterator` is passed a
`callback(err, reduction)` which accepts an optional error as its first
argument, and the state of the reduction as the second. If an error is
passed to the callback, the reduction is stopped and the main `callback` is
`callback(err, reduction)` which accepts an optional error as its first
argument, and the state of the reduction as the second. If an error is
passed to the callback, the reduction is stopped and the main `callback` is
immediately called with the error.
* `callback(err, result)` - A callback which is called after all the `iterator`
* `callback(err, result)` - *Optional* A callback which is called after all the `iterator`
functions have finished. Result is the reduced value.

@@ -562,3 +600,3 @@

<a name="reduceRight" />
### reduceRight(arr, memo, iterator, callback)
### reduceRight(arr, memo, iterator, [callback])

@@ -573,3 +611,3 @@ __Alias:__ `foldr`

<a name="detect" />
### detect(arr, iterator, callback)
### detect(arr, iterator, [callback])

@@ -587,8 +625,8 @@ Returns the first value in `arr` that passes an async truth test. The

* `iterator(item, callback)` - A truth test to apply to each item in `arr`.
The iterator is passed a `callback(truthValue)` which must be called with a
boolean argument once it has completed.
* `callback(result)` - A callback which is called as soon as any iterator returns
The iterator is passed a `callback(truthValue)` which must be called with a
boolean argument once it has completed. **Note: this callback does not take an error as its first argument.**
* `callback(result)` - *Optional* A callback which is called as soon as any iterator returns
`true`, or after all the `iterator` functions have finished. Result will be
the first item in the array that passes the truth test (iterator) or the
value `undefined` if none passed.
value `undefined` if none passed. **Note: this callback does not take an error as its first argument.**

@@ -606,3 +644,3 @@ __Example__

<a name="detectSeries" />
### detectSeries(arr, iterator, callback)
### detectSeries(arr, iterator, [callback])

@@ -617,3 +655,3 @@ The same as [`detect`](#detect), only the `iterator` is applied to each item in `arr`

<a name="sortBy" />
### sortBy(arr, iterator, callback)
### sortBy(arr, iterator, [callback])

@@ -629,3 +667,3 @@ Sorts a list by the results of running each `arr` value through an async `iterator`.

criteria.
* `callback(err, results)` - A callback which is called after all the `iterator`
* `callback(err, results)` - *Optional* A callback which is called after all the `iterator`
functions have finished, or an error occurs. Results is the items from

@@ -670,3 +708,3 @@ the original `arr` sorted by the values returned by the `iterator` calls.

<a name="some" />
### some(arr, iterator, callback)
### some(arr, iterator, [callback])

@@ -685,8 +723,9 @@ __Alias:__ `any`

* `iterator(item, callback)` - A truth test to apply to each item in the array
in parallel. The iterator is passed a callback(truthValue) which must be
in parallel. The iterator is passed a `callback(truthValue)`` which must be
called with a boolean argument once it has completed.
* `callback(result)` - A callback which is called as soon as any iterator returns
* `callback(result)` - *Optional* A callback which is called as soon as any iterator returns
`true`, or after all the iterator functions have finished. Result will be
either `true` or `false` depending on the values of the async tests.
**Note: the callbacks do not take an error as their first argument.**
__Example__

@@ -703,3 +742,3 @@

<a name="every" />
### every(arr, iterator, callback)
### every(arr, iterator, [callback])

@@ -717,8 +756,10 @@ __Alias:__ `all`

* `iterator(item, callback)` - A truth test to apply to each item in the array
in parallel. The iterator is passed a callback(truthValue) which must be
in parallel. The iterator is passed a `callback(truthValue)` which must be
called with a boolean argument once it has completed.
* `callback(result)` - A callback which is called after all the `iterator`
* `callback(result)` - *Optional* A callback which is called after all the `iterator`
functions have finished. Result will be either `true` or `false` depending on
the values of the async tests.
**Note: the callbacks do not take an error as their first argument.**
__Example__

@@ -735,3 +776,3 @@

<a name="concat" />
### concat(arr, iterator, callback)
### concat(arr, iterator, [callback])

@@ -747,5 +788,5 @@ Applies `iterator` to each item in `arr`, concatenating the results. Returns the

* `iterator(item, callback)` - A function to apply to each item in `arr`.
The iterator is passed a `callback(err, results)` which must be called once it
The iterator is passed a `callback(err, results)` which must be called once it
has completed with an error (which can be `null`) and an array of results.
* `callback(err, results)` - A callback which is called after all the `iterator`
* `callback(err, results)` - *Optional* A callback which is called after all the `iterator`
functions have finished, or an error occurs. Results is an array containing

@@ -765,3 +806,3 @@ the concatenated results of the `iterator` function.

<a name="concatSeries" />
### concatSeries(arr, iterator, callback)
### concatSeries(arr, iterator, [callback])

@@ -778,3 +819,3 @@ Same as [`concat`](#concat), but executes in series instead of parallel.

function has completed. If any functions in the series pass an error to its
callback, no more functions are run, and `callback` is immediately called with the value of the error.
callback, no more functions are run, and `callback` is immediately called with the value of the error.
Otherwise, `callback` receives an array of results when `tasks` have completed.

@@ -788,3 +829,3 @@

**Note** that while many implementations preserve the order of object properties, the
[ECMAScript Language Specifcation](http://www.ecma-international.org/ecma-262/5.1/#sec-8.6)
[ECMAScript Language Specifcation](http://www.ecma-international.org/ecma-262/5.1/#sec-8.6)
explicitly states that

@@ -795,3 +836,3 @@

So if you rely on the order in which your series of functions are executed, and want
this to work on all platforms, consider using an array.
this to work on all platforms, consider using an array.

@@ -804,3 +845,3 @@ __Arguments__

* `callback(err, results)` - An optional callback to run once all the functions
have completed. This function gets a results array (or object) containing all
have completed. This function gets a results array (or object) containing all
the result arguments passed to the `task` callbacks.

@@ -864,7 +905,7 @@

* `tasks` - An array or object containing functions to run. Each function is passed
a `callback(err, result)` which it must call on completion with an error `err`
* `tasks` - An array or object containing functions to run. Each function is passed
a `callback(err, result)` which it must call on completion with an error `err`
(which can be `null`) and an optional `result` value.
* `callback(err, results)` - An optional callback to run once all the functions
have completed. This function gets a results array (or object) containing all
have completed. This function gets a results array (or object) containing all
the result arguments passed to the task callbacks.

@@ -917,6 +958,6 @@

The same as [`parallel`](#parallel), only `tasks` are executed in parallel
The same as [`parallel`](#parallel), only `tasks` are executed in parallel
with a maximum of `limit` tasks executing at any time.
Note that the `tasks` are not executed in batches, so there is no guarantee that
Note that the `tasks` are not executed in batches, so there is no guarantee that
the first `limit` tasks will complete before any others are started.

@@ -926,3 +967,3 @@

* `tasks` - An array or object containing functions to run, each function is passed
* `tasks` - An array or object containing functions to run, each function is passed
a `callback(err, result)` it must call on completion with an error `err` (which can

@@ -932,3 +973,3 @@ be `null`) and an optional `result` value.

* `callback(err, results)` - An optional callback to run once all the functions
have completed. This function gets a results array (or object) containing all
have completed. This function gets a results array (or object) containing all
the result arguments passed to the `task` callbacks.

@@ -948,3 +989,3 @@

* `fn(callback)` - A function which is called each time `test` passes. The function is
passed a `callback(err)`, which must be called once it has completed with an
passed a `callback(err)`, which must be called once it has completed with an
optional `err` argument.

@@ -976,4 +1017,4 @@ * `callback(err)` - A callback which is called after the test fails and repeated

The post-check version of [`whilst`](#whilst). To reflect the difference in
the order of operations, the arguments `test` and `fn` are switched.
The post-check version of [`whilst`](#whilst). To reflect the difference in
the order of operations, the arguments `test` and `fn` are switched.

@@ -1002,3 +1043,3 @@ `doWhilst` is to `whilst` as `do while` is to `while` in plain JavaScript.

<a name="forever" />
### forever(fn, errback)
### forever(fn, [errback])

@@ -1036,5 +1077,5 @@ Calls the asynchronous function `fn` with a callback parameter that allows it to

* `tasks` - An array of functions to run, each function is passed a
* `tasks` - An array of functions to run, each function is passed a
`callback(err, result1, result2, ...)` it must call on completion. The first
argument is an error (which can be `null`) and any further arguments will be
argument is an error (which can be `null`) and any further arguments will be
passed as arguments in order to the next task.

@@ -1062,3 +1103,3 @@ * `callback(err, [results])` - An optional callback to run once all the functions

], function (err, result) {
// result now equals 'done'
// result now equals 'done'
});

@@ -1125,3 +1166,3 @@ ```

// Part of an app, that fetches cats of the logged user.
// This example uses `seq` function to avoid overnesting and error
// This example uses `seq` function to avoid overnesting and error
// handling clutter.

@@ -1150,3 +1191,3 @@ app.get('/cats', function(request, response) {

Applies the provided arguments to each function in the array, calling
Applies the provided arguments to each function in the array, calling
`callback` after all functions have completed. If you only provide the first

@@ -1187,7 +1228,7 @@ argument, then it will return a function which lets you pass in the

<a name="queue" />
### queue(worker, concurrency)
### queue(worker, [concurrency])
Creates a `queue` object with the specified `concurrency`. Tasks added to the
`queue` are processed in parallel (up to the `concurrency` limit). If all
`worker`s are in progress, the task is queued until one becomes available.
`worker`s are in progress, the task is queued until one becomes available.
Once a `worker` completes a `task`, that `task`'s callback is called.

@@ -1198,6 +1239,6 @@

* `worker(task, callback)` - An asynchronous function for processing a queued
task, which must call its `callback(err)` argument when finished, with an
optional `error` as an argument.
task, which must call its `callback(err)` argument when finished, with an
optional `error` as an argument. If you want to handle errors from an individual task, pass a callback to `q.push()`.
* `concurrency` - An `integer` for determining how many `worker` functions should be
run in parallel.
run in parallel. If omitted, the concurrency defaults to `1`. If the concurrency is `0`, an error is thrown.

@@ -1216,7 +1257,7 @@ __Queue objects__

alter the concurrency on-the-fly.
* `push(task, [callback])` - add a new task to the `queue`. Calls `callback` once
* `push(task, [callback])` - add a new task to the `queue`. Calls `callback` once
the `worker` has finished processing the task. Instead of a single task, a `tasks` array
can be submitted. The respective callback is used for every task in the list.
* `unshift(task, [callback])` - add a new task to the front of the `queue`.
* `saturated` - a callback that is called when the `queue` length hits the `concurrency` limit,
* `saturated` - a callback that is called when the `queue` length hits the `concurrency` limit,
and further tasks will be queued.

@@ -1289,3 +1330,3 @@ * `empty` - a callback that is called when the last item from the `queue` is given to a `worker`.

the `worker` has completed some tasks, each callback of those tasks is called.
Check out [this animation](https://camo.githubusercontent.com/6bbd36f4cf5b35a0f11a96dcd2e97711ffc2fb37/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130382f62626330636662302d356632392d313165322d393734662d3333393763363464633835382e676966) for how `cargo` and `queue` work.
Check out [these](https://camo.githubusercontent.com/6bbd36f4cf5b35a0f11a96dcd2e97711ffc2fb37/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130382f62626330636662302d356632392d313165322d393734662d3333393763363464633835382e676966) [animations](https://camo.githubusercontent.com/f4810e00e1c5f5f8addbe3e9f49064fd5d102699/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130312f38346339323036362d356632392d313165322d383134662d3964336430323431336266642e676966) for how `cargo` and `queue` work.

@@ -1299,3 +1340,3 @@ While [queue](#queue) passes only one task to one of a group of workers

* `worker(tasks, callback)` - An asynchronous function for processing an array of
queued tasks, which must call its `callback(err)` argument when finished, with
queued tasks, which must call its `callback(err)` argument when finished, with
an optional `err` argument.

@@ -1315,3 +1356,3 @@ * `payload` - An optional `integer` for determining how many tasks should be

* `push(task, [callback])` - Adds `task` to the `queue`. The callback is called
once the `worker` has finished processing the task. Instead of a single task, an array of `tasks`
once the `worker` has finished processing the task. Instead of a single task, an array of `tasks`
can be submitted. The respective callback is used for every task in the list.

@@ -1321,2 +1362,3 @@ * `saturated` - A callback that is called when the `queue.length()` hits the concurrency and further tasks will be queued.

* `drain` - A callback that is called when the last item from the `queue` has returned from the `worker`.
* `idle()`, `pause()`, `resume()`, `kill()` - cargo inherits all of the same methods and event calbacks as [`queue`](#queue)

@@ -1354,14 +1396,14 @@ __Example__

Determines the best order for running the functions in `tasks`, based on their
requirements. Each function can optionally depend on other functions being completed
first, and each function is run as soon as its requirements are satisfied.
Determines the best order for running the functions in `tasks`, based on their
requirements. Each function can optionally depend on other functions being completed
first, and each function is run as soon as its requirements are satisfied.
If any of the functions pass an error to their callback, it will not
complete (so any other functions depending on it will not run), and the main
`callback` is immediately called with the error. Functions also receive an
If any of the functions pass an error to their callback, it will not
complete (so any other functions depending on it will not run), and the main
`callback` is immediately called with the error. Functions also receive an
object containing the results of functions which have completed so far.
Note, all functions are called with a `results` object as a second argument,
Note, all functions are called with a `results` object as a second argument,
so it is unsafe to pass functions in the `tasks` object which cannot handle the
extra argument.
extra argument.

@@ -1383,3 +1425,3 @@ For example, this snippet of code:

Instead, wrap the call to `readFile` in a function which does not forward the
Instead, wrap the call to `readFile` in a function which does not forward the
`results` object:

@@ -1401,9 +1443,9 @@

i.e. can be used when specifying requirements for other tasks.
The function receives two arguments: (1) a `callback(err, result)` which must be
called when finished, passing an `error` (which can be `null`) and the result of
The function receives two arguments: (1) a `callback(err, result)` which must be
called when finished, passing an `error` (which can be `null`) and the result of
the function's execution, and (2) a `results` object, containing the results of
the previously executed functions.
* `callback(err, results)` - An optional callback which is called when all the
tasks have been completed. It receives the `err` argument if any `tasks`
pass an error to their callback. Results are always returned; however, if
tasks have been completed. It receives the `err` argument if any `tasks`
pass an error to their callback. Results are always returned; however, if
an error occurs, no further `tasks` will be performed, and the results

@@ -1499,3 +1541,3 @@ object will only contain partial results.

* `task(callback, results)` - A function which receives two arguments: (1) a `callback(err, result)`
which must be called when finished, passing `err` (which can be `null`) and the `result` of
which must be called when finished, passing `err` (which can be `null`) and the `result` of
the function's execution, and (2) a `results` object, containing the results of

@@ -1569,3 +1611,3 @@ the previously executed functions (if nested inside another control flow).

Creates a continuation function with some arguments already applied.
Creates a continuation function with some arguments already applied.

@@ -1644,5 +1686,5 @@ Useful as a shorthand when combined with other control flow functions. Any arguments

<a name="times" />
### times(n, callback)
### times(n, iterator, [callback])
Calls the `callback` function `n` times, and accumulates results in the same manner
Calls the `iterator` function `n` times, and accumulates results in the same manner
you would use with [`map`](#map).

@@ -1676,6 +1718,6 @@

<a name="timesSeries" />
### timesSeries(n, callback)
### timesSeries(n, iterator, [callback])
The same as [`times`](#times), only the iterator is applied to each item in `arr` in
series. The next `iterator` is only called once the current one has completed.
series. The next `iterator` is only called once the current one has completed.
The results array will be in the same order as the original.

@@ -1730,2 +1772,37 @@

---------------------------------------
<a name="ensureAsync" />
### ensureAsync(fn)
Wrap an async function and ensure it calls its callback on a later tick of the event loop. If the function already calls its callback on a next tick, no extra deferral is added. This is useful for preventing stack overflows (`RangeError: Maximum call stack size exceeded`) and generally keeping [Zalgo](http://blog.izs.me/post/59142742143/designing-apis-for-asynchrony) contained.
__Arguments__
* `fn` - an async function, one that expects a node-style callback as its last argument
Returns a wrapped function with the exact same call signature as the function passed in.
__Example__
```js
function sometimesAsync(arg, callback) {
if (cache[arg]) {
return callback(null, cache[arg]); // this would be synchronous!!
} else {
doSomeIO(arg, callback); // this IO would be asynchronous
}
}
// this has a risk of stack overflows if many results are cached in a row
async.mapSeries(args, sometimesAsync, done);
// this will defer sometimesAsync's callback if necessary,
// preventing stack overflows
async.mapSeries(args, async.ensureAsync(sometimesAsync), done);
```
---------------------------------------
<a name="log" />

@@ -1732,0 +1809,0 @@ ### log(function, arguments)

.jshintrc

Sorry, the diff of this file is not supported yet

.travis.yml

Sorry, the diff of this file is not supported yet

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