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mirror of https://github.com/Jermolene/TiddlyWiki5 synced 2024-11-09 03:19:56 +00:00
TiddlyWiki5/tw5dropbox/plugins/async.js
Jeremy Ruston 5c1ab19573 Started refactoring tw5dropbox into separate wikis
One wiki for the hosted shared app, and one for the wiki app that is
created in the dropbox sandbox
2012-10-10 17:19:19 +01:00

701 lines
21 KiB
JavaScript

/*global setTimeout: false, console: false */
(function () {
var async = {};
// global on the server, window in the browser
var root = this,
previous_async = root.async;
async.noConflict = function () {
root.async = previous_async;
return async;
};
//// cross-browser compatiblity functions ////
var _forEach = function (arr, iterator) {
if (arr.forEach) {
return arr.forEach(iterator);
}
for (var i = 0; i < arr.length; i += 1) {
iterator(arr[i], i, arr);
}
};
var _map = function (arr, iterator) {
if (arr.map) {
return arr.map(iterator);
}
var results = [];
_forEach(arr, function (x, i, a) {
results.push(iterator(x, i, a));
});
return results;
};
var _reduce = function (arr, iterator, memo) {
if (arr.reduce) {
return arr.reduce(iterator, memo);
}
_forEach(arr, function (x, i, a) {
memo = iterator(memo, x, i, a);
});
return memo;
};
var _keys = function (obj) {
if (Object.keys) {
return Object.keys(obj);
}
var keys = [];
for (var k in obj) {
if (obj.hasOwnProperty(k)) {
keys.push(k);
}
}
return keys;
};
//// exported async module functions ////
//// nextTick implementation with browser-compatible fallback ////
if (typeof process === 'undefined' || !(process.nextTick)) {
async.nextTick = function (fn) {
setTimeout(fn, 0);
};
}
else {
async.nextTick = process.nextTick;
}
async.forEach = function (arr, iterator, callback) {
callback = callback || function () {};
if (!arr.length) {
return callback();
}
var completed = 0;
_forEach(arr, function (x) {
iterator(x, function (err) {
if (err) {
callback(err);
callback = function () {};
}
else {
completed += 1;
if (completed === arr.length) {
callback(null);
}
}
});
});
};
async.forEachSeries = function (arr, iterator, callback) {
callback = callback || function () {};
if (!arr.length) {
return callback();
}
var completed = 0;
var iterate = function () {
iterator(arr[completed], function (err) {
if (err) {
callback(err);
callback = function () {};
}
else {
completed += 1;
if (completed === arr.length) {
callback(null);
}
else {
iterate();
}
}
});
};
iterate();
};
async.forEachLimit = function (arr, limit, iterator, callback) {
callback = callback || function () {};
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 = function () {};
}
else {
completed += 1;
running -= 1;
if (completed === arr.length) {
callback();
}
else {
replenish();
}
}
});
}
})();
};
var doParallel = function (fn) {
return function () {
var args = Array.prototype.slice.call(arguments);
return fn.apply(null, [async.forEach].concat(args));
};
};
var doSeries = function (fn) {
return function () {
var args = Array.prototype.slice.call(arguments);
return fn.apply(null, [async.forEachSeries].concat(args));
};
};
var _asyncMap = function (eachfn, arr, iterator, callback) {
var results = [];
arr = _map(arr, function (x, i) {
return {index: i, value: x};
});
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);
async.mapSeries = doSeries(_asyncMap);
// reduce only has a series version, as doing reduce in parallel won't
// work in many situations.
async.reduce = function (arr, memo, iterator, callback) {
async.forEachSeries(arr, function (x, callback) {
iterator(memo, x, function (err, v) {
memo = v;
callback(err);
});
}, function (err) {
callback(err, memo);
});
};
// inject alias
async.inject = async.reduce;
// foldl alias
async.foldl = async.reduce;
async.reduceRight = function (arr, memo, iterator, callback) {
var reversed = _map(arr, function (x) {
return x;
}).reverse();
async.reduce(reversed, memo, iterator, callback);
};
// foldr alias
async.foldr = async.reduceRight;
var _filter = function (eachfn, arr, iterator, callback) {
var results = [];
arr = _map(arr, function (x, i) {
return {index: i, value: x};
});
eachfn(arr, function (x, callback) {
iterator(x.value, function (v) {
if (v) {
results.push(x);
}
callback();
});
}, function (err) {
callback(_map(results.sort(function (a, b) {
return a.index - b.index;
}), function (x) {
return x.value;
}));
});
};
async.filter = doParallel(_filter);
async.filterSeries = doSeries(_filter);
// select alias
async.select = async.filter;
async.selectSeries = async.filterSeries;
var _reject = function (eachfn, arr, iterator, callback) {
var results = [];
arr = _map(arr, function (x, i) {
return {index: i, value: x};
});
eachfn(arr, function (x, callback) {
iterator(x.value, function (v) {
if (!v) {
results.push(x);
}
callback();
});
}, function (err) {
callback(_map(results.sort(function (a, b) {
return a.index - b.index;
}), function (x) {
return x.value;
}));
});
};
async.reject = doParallel(_reject);
async.rejectSeries = doSeries(_reject);
var _detect = function (eachfn, arr, iterator, main_callback) {
eachfn(arr, function (x, callback) {
iterator(x, function (result) {
if (result) {
main_callback(x);
main_callback = function () {};
}
else {
callback();
}
});
}, function (err) {
main_callback();
});
};
async.detect = doParallel(_detect);
async.detectSeries = doSeries(_detect);
async.some = function (arr, iterator, main_callback) {
async.forEach(arr, function (x, callback) {
iterator(x, function (v) {
if (v) {
main_callback(true);
main_callback = function () {};
}
callback();
});
}, function (err) {
main_callback(false);
});
};
// any alias
async.any = async.some;
async.every = function (arr, iterator, main_callback) {
async.forEach(arr, function (x, callback) {
iterator(x, function (v) {
if (!v) {
main_callback(false);
main_callback = function () {};
}
callback();
});
}, function (err) {
main_callback(true);
});
};
// all alias
async.all = async.every;
async.sortBy = function (arr, iterator, callback) {
async.map(arr, function (x, callback) {
iterator(x, function (err, criteria) {
if (err) {
callback(err);
}
else {
callback(null, {value: x, criteria: criteria});
}
});
}, function (err, results) {
if (err) {
return callback(err);
}
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) {
return x.value;
}));
}
});
};
async.auto = function (tasks, callback) {
callback = callback || function () {};
var keys = _keys(tasks);
if (!keys.length) {
return callback(null);
}
var results = {};
var listeners = [];
var addListener = function (fn) {
listeners.unshift(fn);
};
var removeListener = function (fn) {
for (var i = 0; i < listeners.length; i += 1) {
if (listeners[i] === fn) {
listeners.splice(i, 1);
return;
}
}
};
var taskComplete = function () {
_forEach(listeners.slice(0), function (fn) {
fn();
});
};
addListener(function () {
if (_keys(results).length === keys.length) {
callback(null, results);
callback = function () {};
}
});
_forEach(keys, function (k) {
var task = (tasks[k] instanceof Function) ? [tasks[k]]: tasks[k];
var taskCallback = function (err) {
if (err) {
callback(err);
// stop subsequent errors hitting callback multiple times
callback = function () {};
}
else {
var args = Array.prototype.slice.call(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
results[k] = args;
taskComplete();
}
};
var requires = task.slice(0, Math.abs(task.length - 1)) || [];
var ready = function () {
return _reduce(requires, function (a, x) {
return (a && results.hasOwnProperty(x));
}, true) && !results.hasOwnProperty(k);
};
if (ready()) {
task[task.length - 1](taskCallback, results);
}
else {
var listener = function () {
if (ready()) {
removeListener(listener);
task[task.length - 1](taskCallback, results);
}
};
addListener(listener);
}
});
};
async.waterfall = function (tasks, callback) {
callback = callback || function () {};
if (!tasks.length) {
return callback();
}
var wrapIterator = function (iterator) {
return function (err) {
if (err) {
callback(err);
callback = function () {};
}
else {
var args = Array.prototype.slice.call(arguments, 1);
var next = iterator.next();
if (next) {
args.push(wrapIterator(next));
}
else {
args.push(callback);
}
async.nextTick(function () {
iterator.apply(null, args);
});
}
};
};
wrapIterator(async.iterator(tasks))();
};
async.parallel = function (tasks, callback) {
callback = callback || function () {};
if (tasks.constructor === Array) {
async.map(tasks, function (fn, callback) {
if (fn) {
fn(function (err) {
var args = Array.prototype.slice.call(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
callback.call(null, err, args);
});
}
}, callback);
}
else {
var results = {};
async.forEach(_keys(tasks), function (k, callback) {
tasks[k](function (err) {
var args = Array.prototype.slice.call(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
results[k] = args;
callback(err);
});
}, function (err) {
callback(err, results);
});
}
};
async.series = function (tasks, callback) {
callback = callback || function () {};
if (tasks.constructor === Array) {
async.mapSeries(tasks, function (fn, callback) {
if (fn) {
fn(function (err) {
var args = Array.prototype.slice.call(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
callback.call(null, err, args);
});
}
}, callback);
}
else {
var results = {};
async.forEachSeries(_keys(tasks), function (k, callback) {
tasks[k](function (err) {
var args = Array.prototype.slice.call(arguments, 1);
if (args.length <= 1) {
args = args[0];
}
results[k] = args;
callback(err);
});
}, function (err) {
callback(err, results);
});
}
};
async.iterator = function (tasks) {
var makeCallback = function (index) {
var fn = function () {
if (tasks.length) {
tasks[index].apply(null, arguments);
}
return fn.next();
};
fn.next = function () {
return (index < tasks.length - 1) ? makeCallback(index + 1): null;
};
return fn;
};
return makeCallback(0);
};
async.apply = function (fn) {
var args = Array.prototype.slice.call(arguments, 1);
return function () {
return fn.apply(
null, args.concat(Array.prototype.slice.call(arguments))
);
};
};
var _concat = function (eachfn, arr, fn, callback) {
var r = [];
eachfn(arr, function (x, cb) {
fn(x, function (err, y) {
r = r.concat(y || []);
cb(err);
});
}, function (err) {
callback(err, r);
});
};
async.concat = doParallel(_concat);
async.concatSeries = doSeries(_concat);
async.whilst = function (test, iterator, callback) {
if (test()) {
iterator(function (err) {
if (err) {
return callback(err);
}
async.whilst(test, iterator, callback);
});
}
else {
callback();
}
};
async.until = function (test, iterator, callback) {
if (!test()) {
iterator(function (err) {
if (err) {
return callback(err);
}
async.until(test, iterator, callback);
});
}
else {
callback();
}
};
async.queue = function (worker, concurrency) {
var workers = 0;
var q = {
tasks: [],
concurrency: concurrency,
saturated: null,
empty: null,
drain: null,
push: function (data, callback) {
if(data.constructor !== Array) {
data = [data];
}
_forEach(data, function(task) {
q.tasks.push({
data: task,
callback: typeof callback === 'function' ? callback : null
});
if (q.saturated && q.tasks.length == concurrency) {
q.saturated();
}
async.nextTick(q.process);
});
},
process: function () {
if (workers < q.concurrency && q.tasks.length) {
var task = q.tasks.shift();
if(q.empty && q.tasks.length == 0) q.empty();
workers += 1;
worker(task.data, function () {
workers -= 1;
if (task.callback) {
task.callback.apply(task, arguments);
}
if(q.drain && q.tasks.length + workers == 0) q.drain();
q.process();
});
}
},
length: function () {
return q.tasks.length;
},
running: function () {
return workers;
}
};
return q;
};
var _console_fn = function (name) {
return function (fn) {
var args = Array.prototype.slice.call(arguments, 1);
fn.apply(null, args.concat([function (err) {
var args = Array.prototype.slice.call(arguments, 1);
if (typeof console !== 'undefined') {
if (err) {
if (console.error) {
console.error(err);
}
}
else if (console[name]) {
_forEach(args, function (x) {
console[name](x);
});
}
}
}]));
};
};
async.log = _console_fn('log');
async.dir = _console_fn('dir');
/*async.info = _console_fn('info');
async.warn = _console_fn('warn');
async.error = _console_fn('error');*/
async.memoize = function (fn, hasher) {
var memo = {};
var queues = {};
hasher = hasher || function (x) {
return x;
};
var memoized = function () {
var args = Array.prototype.slice.call(arguments);
var callback = args.pop();
var key = hasher.apply(null, args);
if (key in memo) {
callback.apply(null, memo[key]);
}
else if (key in queues) {
queues[key].push(callback);
}
else {
queues[key] = [callback];
fn.apply(null, args.concat([function () {
memo[key] = arguments;
var q = queues[key];
delete queues[key];
for (var i = 0, l = q.length; i < l; i++) {
q[i].apply(null, arguments);
}
}]));
}
};
memoized.unmemoized = fn;
return memoized;
};
async.unmemoize = function (fn) {
return function () {
return (fn.unmemoized || fn).apply(null, arguments);
};
};
// AMD / RequireJS
if (typeof define !== 'undefined' && define.amd) {
define('async', [], function () {
return async;
});
}
// Node.js
else if (typeof module !== 'undefined' && module.exports) {
module.exports = async;
}
// included directly via <script> tag
else {
root.async = async;
}
}());