RPC tests

3 files changed, 5360 insertions, 0 deletions

diff --git a/RPCTests/modules/async.js b/RPCTests/modules/async.js
new file mode 100644
index 000000000..282ff437b
--- /dev/null
+++ b/RPCTests/modules/async.js
@@ -0,0 +1,5289 @@
+(function (global, factory) {
+    typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
+    typeof define === 'function' && define.amd ? define(['exports'], factory) :
+    (factory((global.async = global.async || {})));
+}(this, (function (exports) { 'use strict';
+
+/**
+ * A faster alternative to `Function#apply`, this function invokes `func`
+ * with the `this` binding of `thisArg` and the arguments of `args`.
+ *
+ * @private
+ * @param {Function} func The function to invoke.
+ * @param {*} thisArg The `this` binding of `func`.
+ * @param {Array} args The arguments to invoke `func` with.
+ * @returns {*} Returns the result of `func`.
+ */
+function apply(func, thisArg, args) {
+  switch (args.length) {
+    case 0: return func.call(thisArg);
+    case 1: return func.call(thisArg, args[0]);
+    case 2: return func.call(thisArg, args[0], args[1]);
+    case 3: return func.call(thisArg, args[0], args[1], args[2]);
+  }
+  return func.apply(thisArg, args);
+}
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
+
+/**
+ * A specialized version of `baseRest` which transforms the rest array.
+ *
+ * @private
+ * @param {Function} func The function to apply a rest parameter to.
+ * @param {number} [start=func.length-1] The start position of the rest parameter.
+ * @param {Function} transform The rest array transform.
+ * @returns {Function} Returns the new function.
+ */
+function overRest$1(func, start, transform) {
+  start = nativeMax(start === undefined ? (func.length - 1) : start, 0);
+  return function() {
+    var args = arguments,
+        index = -1,
+        length = nativeMax(args.length - start, 0),
+        array = Array(length);
+
+    while (++index < length) {
+      array[index] = args[start + index];
+    }
+    index = -1;
+    var otherArgs = Array(start + 1);
+    while (++index < start) {
+      otherArgs[index] = args[index];
+    }
+    otherArgs[start] = transform(array);
+    return apply(func, this, otherArgs);
+  };
+}
+
+/**
+ * This method returns the first argument it receives.
+ *
+ * @static
+ * @since 0.1.0
+ * @memberOf _
+ * @category Util
+ * @param {*} value Any value.
+ * @returns {*} Returns `value`.
+ * @example
+ *
+ * var object = { 'a': 1 };
+ *
+ * console.log(_.identity(object) === object);
+ * // => true
+ */
+function identity(value) {
+  return value;
+}
+
+// Lodash rest function without function.toString()
+// remappings
+function rest(func, start) {
+    return overRest$1(func, start, identity);
+}
+
+var initialParams = function (fn) {
+    return rest(function (args /*..., callback*/) {
+        var callback = args.pop();
+        fn.call(this, args, callback);
+    });
+};
+
+function applyEach$1(eachfn) {
+    return rest(function (fns, args) {
+        var go = initialParams(function (args, callback) {
+            var that = this;
+            return eachfn(fns, function (fn, cb) {
+                fn.apply(that, args.concat(cb));
+            }, callback);
+        });
+        if (args.length) {
+            return go.apply(this, args);
+        } else {
+            return go;
+        }
+    });
+}
+
+/** Detect free variable `global` from Node.js. */
+var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;
+
+/** Detect free variable `self`. */
+var freeSelf = typeof self == 'object' && self && self.Object === Object && self;
+
+/** Used as a reference to the global object. */
+var root = freeGlobal || freeSelf || Function('return this')();
+
+/** Built-in value references. */
+var Symbol$1 = root.Symbol;
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/**
+ * Used to resolve the
+ * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
+ * of values.
+ */
+var nativeObjectToString = objectProto.toString;
+
+/** Built-in value references. */
+var symToStringTag$1 = Symbol$1 ? Symbol$1.toStringTag : undefined;
+
+/**
+ * A specialized version of `baseGetTag` which ignores `Symbol.toStringTag` values.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @returns {string} Returns the raw `toStringTag`.
+ */
+function getRawTag(value) {
+  var isOwn = hasOwnProperty.call(value, symToStringTag$1),
+      tag = value[symToStringTag$1];
+
+  try {
+    value[symToStringTag$1] = undefined;
+    var unmasked = true;
+  } catch (e) {}
+
+  var result = nativeObjectToString.call(value);
+  if (unmasked) {
+    if (isOwn) {
+      value[symToStringTag$1] = tag;
+    } else {
+      delete value[symToStringTag$1];
+    }
+  }
+  return result;
+}
+
+/** Used for built-in method references. */
+var objectProto$1 = Object.prototype;
+
+/**
+ * Used to resolve the
+ * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
+ * of values.
+ */
+var nativeObjectToString$1 = objectProto$1.toString;
+
+/**
+ * Converts `value` to a string using `Object.prototype.toString`.
+ *
+ * @private
+ * @param {*} value The value to convert.
+ * @returns {string} Returns the converted string.
+ */
+function objectToString(value) {
+  return nativeObjectToString$1.call(value);
+}
+
+/** `Object#toString` result references. */
+var nullTag = '[object Null]';
+var undefinedTag = '[object Undefined]';
+
+/** Built-in value references. */
+var symToStringTag = Symbol$1 ? Symbol$1.toStringTag : undefined;
+
+/**
+ * The base implementation of `getTag` without fallbacks for buggy environments.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @returns {string} Returns the `toStringTag`.
+ */
+function baseGetTag(value) {
+  if (value == null) {
+    return value === undefined ? undefinedTag : nullTag;
+  }
+  value = Object(value);
+  return (symToStringTag && symToStringTag in value)
+    ? getRawTag(value)
+    : objectToString(value);
+}
+
+/**
+ * Checks if `value` is the
+ * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
+ * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an object, else `false`.
+ * @example
+ *
+ * _.isObject({});
+ * // => true
+ *
+ * _.isObject([1, 2, 3]);
+ * // => true
+ *
+ * _.isObject(_.noop);
+ * // => true
+ *
+ * _.isObject(null);
+ * // => false
+ */
+function isObject(value) {
+  var type = typeof value;
+  return value != null && (type == 'object' || type == 'function');
+}
+
+/** `Object#toString` result references. */
+var asyncTag = '[object AsyncFunction]';
+var funcTag = '[object Function]';
+var genTag = '[object GeneratorFunction]';
+var proxyTag = '[object Proxy]';
+
+/**
+ * Checks if `value` is classified as a `Function` object.
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a function, else `false`.
+ * @example
+ *
+ * _.isFunction(_);
+ * // => true
+ *
+ * _.isFunction(/abc/);
+ * // => false
+ */
+function isFunction(value) {
+  if (!isObject(value)) {
+    return false;
+  }
+  // The use of `Object#toString` avoids issues with the `typeof` operator
+  // in Safari 9 which returns 'object' for typed arrays and other constructors.
+  var tag = baseGetTag(value);
+  return tag == funcTag || tag == genTag || tag == asyncTag || tag == proxyTag;
+}
+
+/** Used as references for various `Number` constants. */
+var MAX_SAFE_INTEGER = 9007199254740991;
+
+/**
+ * Checks if `value` is a valid array-like length.
+ *
+ * **Note:** This method is loosely based on
+ * [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
+ * @example
+ *
+ * _.isLength(3);
+ * // => true
+ *
+ * _.isLength(Number.MIN_VALUE);
+ * // => false
+ *
+ * _.isLength(Infinity);
+ * // => false
+ *
+ * _.isLength('3');
+ * // => false
+ */
+function isLength(value) {
+  return typeof value == 'number' &&
+    value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
+}
+
+/**
+ * Checks if `value` is array-like. A value is considered array-like if it's
+ * not a function and has a `value.length` that's an integer greater than or
+ * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is array-like, else `false`.
+ * @example
+ *
+ * _.isArrayLike([1, 2, 3]);
+ * // => true
+ *
+ * _.isArrayLike(document.body.children);
+ * // => true
+ *
+ * _.isArrayLike('abc');
+ * // => true
+ *
+ * _.isArrayLike(_.noop);
+ * // => false
+ */
+function isArrayLike(value) {
+  return value != null && isLength(value.length) && !isFunction(value);
+}
+
+/**
+ * This method returns `undefined`.
+ *
+ * @static
+ * @memberOf _
+ * @since 2.3.0
+ * @category Util
+ * @example
+ *
+ * _.times(2, _.noop);
+ * // => [undefined, undefined]
+ */
+function noop() {
+  // No operation performed.
+}
+
+function once(fn) {
+    return function () {
+        if (fn === null) return;
+        var callFn = fn;
+        fn = null;
+        callFn.apply(this, arguments);
+    };
+}
+
+var iteratorSymbol = typeof Symbol === 'function' && Symbol.iterator;
+
+var getIterator = function (coll) {
+    return iteratorSymbol && coll[iteratorSymbol] && coll[iteratorSymbol]();
+};
+
+/**
+ * The base implementation of `_.times` without support for iteratee shorthands
+ * or max array length checks.
+ *
+ * @private
+ * @param {number} n The number of times to invoke `iteratee`.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @returns {Array} Returns the array of results.
+ */
+function baseTimes(n, iteratee) {
+  var index = -1,
+      result = Array(n);
+
+  while (++index < n) {
+    result[index] = iteratee(index);
+  }
+  return result;
+}
+
+/**
+ * Checks if `value` is object-like. A value is object-like if it's not `null`
+ * and has a `typeof` result of "object".
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
+ * @example
+ *
+ * _.isObjectLike({});
+ * // => true
+ *
+ * _.isObjectLike([1, 2, 3]);
+ * // => true
+ *
+ * _.isObjectLike(_.noop);
+ * // => false
+ *
+ * _.isObjectLike(null);
+ * // => false
+ */
+function isObjectLike(value) {
+  return value != null && typeof value == 'object';
+}
+
+/** `Object#toString` result references. */
+var argsTag = '[object Arguments]';
+
+/**
+ * The base implementation of `_.isArguments`.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an `arguments` object,
+ */
+function baseIsArguments(value) {
+  return isObjectLike(value) && baseGetTag(value) == argsTag;
+}
+
+/** Used for built-in method references. */
+var objectProto$3 = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty$2 = objectProto$3.hasOwnProperty;
+
+/** Built-in value references. */
+var propertyIsEnumerable = objectProto$3.propertyIsEnumerable;
+
+/**
+ * Checks if `value` is likely an `arguments` object.
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an `arguments` object,
+ *  else `false`.
+ * @example
+ *
+ * _.isArguments(function() { return arguments; }());
+ * // => true
+ *
+ * _.isArguments([1, 2, 3]);
+ * // => false
+ */
+var isArguments = baseIsArguments(function() { return arguments; }()) ? baseIsArguments : function(value) {
+  return isObjectLike(value) && hasOwnProperty$2.call(value, 'callee') &&
+    !propertyIsEnumerable.call(value, 'callee');
+};
+
+/**
+ * Checks if `value` is classified as an `Array` object.
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an array, else `false`.
+ * @example
+ *
+ * _.isArray([1, 2, 3]);
+ * // => true
+ *
+ * _.isArray(document.body.children);
+ * // => false
+ *
+ * _.isArray('abc');
+ * // => false
+ *
+ * _.isArray(_.noop);
+ * // => false
+ */
+var isArray = Array.isArray;
+
+/**
+ * This method returns `false`.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.13.0
+ * @category Util
+ * @returns {boolean} Returns `false`.
+ * @example
+ *
+ * _.times(2, _.stubFalse);
+ * // => [false, false]
+ */
+function stubFalse() {
+  return false;
+}
+
+/** Detect free variable `exports`. */
+var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports;
+
+/** Detect free variable `module`. */
+var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module;
+
+/** Detect the popular CommonJS extension `module.exports`. */
+var moduleExports = freeModule && freeModule.exports === freeExports;
+
+/** Built-in value references. */
+var Buffer = moduleExports ? root.Buffer : undefined;
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined;
+
+/**
+ * Checks if `value` is a buffer.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.3.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a buffer, else `false`.
+ * @example
+ *
+ * _.isBuffer(new Buffer(2));
+ * // => true
+ *
+ * _.isBuffer(new Uint8Array(2));
+ * // => false
+ */
+var isBuffer = nativeIsBuffer || stubFalse;
+
+/** Used as references for various `Number` constants. */
+var MAX_SAFE_INTEGER$1 = 9007199254740991;
+
+/** Used to detect unsigned integer values. */
+var reIsUint = /^(?:0|[1-9]\d*)$/;
+
+/**
+ * Checks if `value` is a valid array-like index.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
+ * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
+ */
+function isIndex(value, length) {
+  length = length == null ? MAX_SAFE_INTEGER$1 : length;
+  return !!length &&
+    (typeof value == 'number' || reIsUint.test(value)) &&
+    (value > -1 && value % 1 == 0 && value < length);
+}
+
+/** `Object#toString` result references. */
+var argsTag$1 = '[object Arguments]';
+var arrayTag = '[object Array]';
+var boolTag = '[object Boolean]';
+var dateTag = '[object Date]';
+var errorTag = '[object Error]';
+var funcTag$1 = '[object Function]';
+var mapTag = '[object Map]';
+var numberTag = '[object Number]';
+var objectTag = '[object Object]';
+var regexpTag = '[object RegExp]';
+var setTag = '[object Set]';
+var stringTag = '[object String]';
+var weakMapTag = '[object WeakMap]';
+
+var arrayBufferTag = '[object ArrayBuffer]';
+var dataViewTag = '[object DataView]';
+var float32Tag = '[object Float32Array]';
+var float64Tag = '[object Float64Array]';
+var int8Tag = '[object Int8Array]';
+var int16Tag = '[object Int16Array]';
+var int32Tag = '[object Int32Array]';
+var uint8Tag = '[object Uint8Array]';
+var uint8ClampedTag = '[object Uint8ClampedArray]';
+var uint16Tag = '[object Uint16Array]';
+var uint32Tag = '[object Uint32Array]';
+
+/** Used to identify `toStringTag` values of typed arrays. */
+var typedArrayTags = {};
+typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
+typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
+typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
+typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
+typedArrayTags[uint32Tag] = true;
+typedArrayTags[argsTag$1] = typedArrayTags[arrayTag] =
+typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
+typedArrayTags[dataViewTag] = typedArrayTags[dateTag] =
+typedArrayTags[errorTag] = typedArrayTags[funcTag$1] =
+typedArrayTags[mapTag] = typedArrayTags[numberTag] =
+typedArrayTags[objectTag] = typedArrayTags[regexpTag] =
+typedArrayTags[setTag] = typedArrayTags[stringTag] =
+typedArrayTags[weakMapTag] = false;
+
+/**
+ * The base implementation of `_.isTypedArray` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
+ */
+function baseIsTypedArray(value) {
+  return isObjectLike(value) &&
+    isLength(value.length) && !!typedArrayTags[baseGetTag(value)];
+}
+
+/**
+ * The base implementation of `_.unary` without support for storing metadata.
+ *
+ * @private
+ * @param {Function} func The function to cap arguments for.
+ * @returns {Function} Returns the new capped function.
+ */
+function baseUnary(func) {
+  return function(value) {
+    return func(value);
+  };
+}
+
+/** Detect free variable `exports`. */
+var freeExports$1 = typeof exports == 'object' && exports && !exports.nodeType && exports;
+
+/** Detect free variable `module`. */
+var freeModule$1 = freeExports$1 && typeof module == 'object' && module && !module.nodeType && module;
+
+/** Detect the popular CommonJS extension `module.exports`. */
+var moduleExports$1 = freeModule$1 && freeModule$1.exports === freeExports$1;
+
+/** Detect free variable `process` from Node.js. */
+var freeProcess = moduleExports$1 && freeGlobal.process;
+
+/** Used to access faster Node.js helpers. */
+var nodeUtil = (function() {
+  try {
+    return freeProcess && freeProcess.binding('util');
+  } catch (e) {}
+}());
+
+/* Node.js helper references. */
+var nodeIsTypedArray = nodeUtil && nodeUtil.isTypedArray;
+
+/**
+ * Checks if `value` is classified as a typed array.
+ *
+ * @static
+ * @memberOf _
+ * @since 3.0.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
+ * @example
+ *
+ * _.isTypedArray(new Uint8Array);
+ * // => true
+ *
+ * _.isTypedArray([]);
+ * // => false
+ */
+var isTypedArray = nodeIsTypedArray ? baseUnary(nodeIsTypedArray) : baseIsTypedArray;
+
+/** Used for built-in method references. */
+var objectProto$2 = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty$1 = objectProto$2.hasOwnProperty;
+
+/**
+ * Creates an array of the enumerable property names of the array-like `value`.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @param {boolean} inherited Specify returning inherited property names.
+ * @returns {Array} Returns the array of property names.
+ */
+function arrayLikeKeys(value, inherited) {
+  var isArr = isArray(value),
+      isArg = !isArr && isArguments(value),
+      isBuff = !isArr && !isArg && isBuffer(value),
+      isType = !isArr && !isArg && !isBuff && isTypedArray(value),
+      skipIndexes = isArr || isArg || isBuff || isType,
+      result = skipIndexes ? baseTimes(value.length, String) : [],
+      length = result.length;
+
+  for (var key in value) {
+    if ((inherited || hasOwnProperty$1.call(value, key)) &&
+        !(skipIndexes && (
+           // Safari 9 has enumerable `arguments.length` in strict mode.
+           key == 'length' ||
+           // Node.js 0.10 has enumerable non-index properties on buffers.
+           (isBuff && (key == 'offset' || key == 'parent')) ||
+           // PhantomJS 2 has enumerable non-index properties on typed arrays.
+           (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
+           // Skip index properties.
+           isIndex(key, length)
+        ))) {
+      result.push(key);
+    }
+  }
+  return result;
+}
+
+/** Used for built-in method references. */
+var objectProto$5 = Object.prototype;
+
+/**
+ * Checks if `value` is likely a prototype object.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a prototype, else `false`.
+ */
+function isPrototype(value) {
+  var Ctor = value && value.constructor,
+      proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto$5;
+
+  return value === proto;
+}
+
+/**
+ * Creates a unary function that invokes `func` with its argument transformed.
+ *
+ * @private
+ * @param {Function} func The function to wrap.
+ * @param {Function} transform The argument transform.
+ * @returns {Function} Returns the new function.
+ */
+function overArg(func, transform) {
+  return function(arg) {
+    return func(transform(arg));
+  };
+}
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeKeys = overArg(Object.keys, Object);
+
+/** Used for built-in method references. */
+var objectProto$4 = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty$3 = objectProto$4.hasOwnProperty;
+
+/**
+ * The base implementation of `_.keys` which doesn't treat sparse arrays as dense.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the array of property names.
+ */
+function baseKeys(object) {
+  if (!isPrototype(object)) {
+    return nativeKeys(object);
+  }
+  var result = [];
+  for (var key in Object(object)) {
+    if (hasOwnProperty$3.call(object, key) && key != 'constructor') {
+      result.push(key);
+    }
+  }
+  return result;
+}
+
+/**
+ * Creates an array of the own enumerable property names of `object`.
+ *
+ * **Note:** Non-object values are coerced to objects. See the
+ * [ES spec](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
+ * for more details.
+ *
+ * @static
+ * @since 0.1.0
+ * @memberOf _
+ * @category Object
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the array of property names.
+ * @example
+ *
+ * function Foo() {
+ *   this.a = 1;
+ *   this.b = 2;
+ * }
+ *
+ * Foo.prototype.c = 3;
+ *
+ * _.keys(new Foo);
+ * // => ['a', 'b'] (iteration order is not guaranteed)
+ *
+ * _.keys('hi');
+ * // => ['0', '1']
+ */
+function keys(object) {
+  return isArrayLike(object) ? arrayLikeKeys(object) : baseKeys(object);
+}
+
+function createArrayIterator(coll) {
+    var i = -1;
+    var len = coll.length;
+    return function next() {
+        return ++i < len ? { value: coll[i], key: i } : null;
+    };
+}
+
+function createES2015Iterator(iterator) {
+    var i = -1;
+    return function next() {
+        var item = iterator.next();
+        if (item.done) return null;
+        i++;
+        return { value: item.value, key: i };
+    };
+}
+
+function createObjectIterator(obj) {
+    var okeys = keys(obj);
+    var i = -1;
+    var len = okeys.length;
+    return function next() {
+        var key = okeys[++i];
+        return i < len ? { value: obj[key], key: key } : null;
+    };
+}
+
+function iterator(coll) {
+    if (isArrayLike(coll)) {
+        return createArrayIterator(coll);
+    }
+
+    var iterator = getIterator(coll);
+    return iterator ? createES2015Iterator(iterator) : createObjectIterator(coll);
+}
+
+function onlyOnce(fn) {
+    return function () {
+        if (fn === null) throw new Error("Callback was already called.");
+        var callFn = fn;
+        fn = null;
+        callFn.apply(this, arguments);
+    };
+}
+
+// A temporary value used to identify if the loop should be broken.
+// See #1064, #1293
+var breakLoop = {};
+
+function _eachOfLimit(limit) {
+    return function (obj, iteratee, callback) {
+        callback = once(callback || noop);
+        if (limit <= 0 || !obj) {
+            return callback(null);
+        }
+        var nextElem = iterator(obj);
+        var done = false;
+        var running = 0;
+
+        function iterateeCallback(err, value) {
+            running -= 1;
+            if (err) {
+                done = true;
+                callback(err);
+            } else if (value === breakLoop || done && running <= 0) {
+                done = true;
+                return callback(null);
+            } else {
+                replenish();
+            }
+        }
+
+        function replenish() {
+            while (running < limit && !done) {
+                var elem = nextElem();
+                if (elem === null) {
+                    done = true;
+                    if (running <= 0) {
+                        callback(null);
+                    }
+                    return;
+                }
+                running += 1;
+                iteratee(elem.value, elem.key, onlyOnce(iterateeCallback));
+            }
+        }
+
+        replenish();
+    };
+}
+
+/**
+ * The same as [`eachOf`]{@link module:Collections.eachOf} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name eachOfLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.eachOf]{@link module:Collections.eachOf}
+ * @alias forEachOfLimit
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A function to apply to each
+ * item in `coll`. The `key` is the item's key, or index in the case of an
+ * array. The iteratee 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. Invoked with
+ * (item, key, callback).
+ * @param {Function} [callback] - A callback which is called when all
+ * `iteratee` functions have finished, or an error occurs. Invoked with (err).
+ */
+function eachOfLimit(coll, limit, iteratee, callback) {
+  _eachOfLimit(limit)(coll, iteratee, callback);
+}
+
+function doLimit(fn, limit) {
+    return function (iterable, iteratee, callback) {
+        return fn(iterable, limit, iteratee, callback);
+    };
+}
+
+// eachOf implementation optimized for array-likes
+function eachOfArrayLike(coll, iteratee, callback) {
+    callback = once(callback || noop);
+    var index = 0,
+        completed = 0,
+        length = coll.length;
+    if (length === 0) {
+        callback(null);
+    }
+
+    function iteratorCallback(err) {
+        if (err) {
+            callback(err);
+        } else if (++completed === length) {
+            callback(null);
+        }
+    }
+
+    for (; index < length; index++) {
+        iteratee(coll[index], index, onlyOnce(iteratorCallback));
+    }
+}
+
+// a generic version of eachOf which can handle array, object, and iterator cases.
+var eachOfGeneric = doLimit(eachOfLimit, Infinity);
+
+/**
+ * Like [`each`]{@link module:Collections.each}, except that it passes the key (or index) as the second argument
+ * to the iteratee.
+ *
+ * @name eachOf
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias forEachOf
+ * @category Collection
+ * @see [async.each]{@link module:Collections.each}
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each
+ * item in `coll`. The `key` is the item's key, or index in the case of an
+ * array. The iteratee 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. Invoked with
+ * (item, key, callback).
+ * @param {Function} [callback] - A callback which is called when all
+ * `iteratee` functions have finished, or an error occurs. Invoked with (err).
+ * @example
+ *
+ * var obj = {dev: "/dev.json", test: "/test.json", prod: "/prod.json"};
+ * var configs = {};
+ *
+ * async.forEachOf(obj, function (value, key, callback) {
+ *     fs.readFile(__dirname + value, "utf8", function (err, data) {
+ *         if (err) return callback(err);
+ *         try {
+ *             configs[key] = JSON.parse(data);
+ *         } catch (e) {
+ *             return callback(e);
+ *         }
+ *         callback();
+ *     });
+ * }, function (err) {
+ *     if (err) console.error(err.message);
+ *     // configs is now a map of JSON data
+ *     doSomethingWith(configs);
+ * });
+ */
+var eachOf = function (coll, iteratee, callback) {
+    var eachOfImplementation = isArrayLike(coll) ? eachOfArrayLike : eachOfGeneric;
+    eachOfImplementation(coll, iteratee, callback);
+};
+
+function doParallel(fn) {
+    return function (obj, iteratee, callback) {
+        return fn(eachOf, obj, iteratee, callback);
+    };
+}
+
+function _asyncMap(eachfn, arr, iteratee, callback) {
+    callback = callback || noop;
+    arr = arr || [];
+    var results = [];
+    var counter = 0;
+
+    eachfn(arr, function (value, _, callback) {
+        var index = counter++;
+        iteratee(value, function (err, v) {
+            results[index] = v;
+            callback(err);
+        });
+    }, function (err) {
+        callback(err, results);
+    });
+}
+
+/**
+ * Produces a new collection of values by mapping each value in `coll` through
+ * the `iteratee` function. The `iteratee` is called with an item from `coll`
+ * and a callback for when it has finished processing. Each of these callback
+ * takes 2 arguments: an `error`, and the transformed item from `coll`. If
+ * `iteratee` 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 `iteratee` to each item in
+ * parallel, there is no guarantee that the `iteratee` functions will complete
+ * in order. However, the results array will be in the same order as the
+ * original `coll`.
+ *
+ * If `map` is passed an Object, the results will be an Array.  The results
+ * will roughly be in the order of the original Objects' keys (but this can
+ * vary across JavaScript engines)
+ *
+ * @name map
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee 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. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. Results is an Array of the
+ * transformed items from the `coll`. Invoked with (err, results).
+ * @example
+ *
+ * async.map(['file1','file2','file3'], fs.stat, function(err, results) {
+ *     // results is now an array of stats for each file
+ * });
+ */
+var map = doParallel(_asyncMap);
+
+/**
+ * Applies the provided arguments to each function in the array, calling
+ * `callback` after all functions have completed. If you only provide the first
+ * argument, `fns`, then it will return a function which lets you pass in the
+ * arguments as if it were a single function call. If more arguments are
+ * provided, `callback` is required while `args` is still optional.
+ *
+ * @name applyEach
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array|Iterable|Object} fns - A collection of asynchronous functions
+ * to all call with the same arguments
+ * @param {...*} [args] - any number of separate arguments to pass to the
+ * function.
+ * @param {Function} [callback] - the final argument should be the callback,
+ * called when all functions have completed processing.
+ * @returns {Function} - If only the first argument, `fns`, is provided, it will
+ * return a function which lets you pass in the arguments as if it were a single
+ * function call. The signature is `(..args, callback)`. If invoked with any
+ * arguments, `callback` is required.
+ * @example
+ *
+ * async.applyEach([enableSearch, updateSchema], 'bucket', callback);
+ *
+ * // partial application example:
+ * async.each(
+ *     buckets,
+ *     async.applyEach([enableSearch, updateSchema]),
+ *     callback
+ * );
+ */
+var applyEach = applyEach$1(map);
+
+function doParallelLimit(fn) {
+    return function (obj, limit, iteratee, callback) {
+        return fn(_eachOfLimit(limit), obj, iteratee, callback);
+    };
+}
+
+/**
+ * The same as [`map`]{@link module:Collections.map} but runs a maximum of `limit` async operations at a time.
+ *
+ * @name mapLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.map]{@link module:Collections.map}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee 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. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. Results is an array of the
+ * transformed items from the `coll`. Invoked with (err, results).
+ */
+var mapLimit = doParallelLimit(_asyncMap);
+
+/**
+ * The same as [`map`]{@link module:Collections.map} but runs only a single async operation at a time.
+ *
+ * @name mapSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.map]{@link module:Collections.map}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee 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. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. Results is an array of the
+ * transformed items from the `coll`. Invoked with (err, results).
+ */
+var mapSeries = doLimit(mapLimit, 1);
+
+/**
+ * The same as [`applyEach`]{@link module:ControlFlow.applyEach} but runs only a single async operation at a time.
+ *
+ * @name applyEachSeries
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.applyEach]{@link module:ControlFlow.applyEach}
+ * @category Control Flow
+ * @param {Array|Iterable|Object} fns - A collection of asynchronous functions to all
+ * call with the same arguments
+ * @param {...*} [args] - any number of separate arguments to pass to the
+ * function.
+ * @param {Function} [callback] - the final argument should be the callback,
+ * called when all functions have completed processing.
+ * @returns {Function} - If only the first argument is provided, it will return
+ * a function which lets you pass in the arguments as if it were a single
+ * function call.
+ */
+var applyEachSeries = applyEach$1(mapSeries);
+
+/**
+ * Creates a continuation function with some arguments already applied.
+ *
+ * Useful as a shorthand when combined with other control flow functions. Any
+ * arguments passed to the returned function are added to the arguments
+ * originally passed to apply.
+ *
+ * @name apply
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} function - The function you want to eventually apply all
+ * arguments to. Invokes with (arguments...).
+ * @param {...*} arguments... - Any number of arguments to automatically apply
+ * when the continuation is called.
+ * @example
+ *
+ * // using apply
+ * async.parallel([
+ *     async.apply(fs.writeFile, 'testfile1', 'test1'),
+ *     async.apply(fs.writeFile, 'testfile2', 'test2')
+ * ]);
+ *
+ *
+ * // the same process without using apply
+ * async.parallel([
+ *     function(callback) {
+ *         fs.writeFile('testfile1', 'test1', callback);
+ *     },
+ *     function(callback) {
+ *         fs.writeFile('testfile2', 'test2', callback);
+ *     }
+ * ]);
+ *
+ * // It's possible to pass any number of additional arguments when calling the
+ * // continuation:
+ *
+ * node> var fn = async.apply(sys.puts, 'one');
+ * node> fn('two', 'three');
+ * one
+ * two
+ * three
+ */
+var apply$2 = rest(function (fn, args) {
+    return rest(function (callArgs) {
+        return fn.apply(null, args.concat(callArgs));
+    });
+});
+
+/**
+ * Take a sync function and make it async, passing its return value to a
+ * callback. This is useful for plugging sync functions into a waterfall,
+ * series, or other async functions. Any arguments passed to the generated
+ * function will be passed to the wrapped function (except for the final
+ * callback argument). Errors thrown will be passed to the callback.
+ *
+ * If the function passed to `asyncify` returns a Promise, that promises's
+ * resolved/rejected state will be used to call the callback, rather than simply
+ * the synchronous return value.
+ *
+ * This also means you can asyncify ES2016 `async` functions.
+ *
+ * @name asyncify
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @alias wrapSync
+ * @category Util
+ * @param {Function} func - The synchronous function to convert to an
+ * asynchronous function.
+ * @returns {Function} An asynchronous wrapper of the `func`. To be invoked with
+ * (callback).
+ * @example
+ *
+ * // passing a regular synchronous function
+ * async.waterfall([
+ *     async.apply(fs.readFile, filename, "utf8"),
+ *     async.asyncify(JSON.parse),
+ *     function (data, next) {
+ *         // data is the result of parsing the text.
+ *         // If there was a parsing error, it would have been caught.
+ *     }
+ * ], callback);
+ *
+ * // passing a function returning a promise
+ * async.waterfall([
+ *     async.apply(fs.readFile, filename, "utf8"),
+ *     async.asyncify(function (contents) {
+ *         return db.model.create(contents);
+ *     }),
+ *     function (model, next) {
+ *         // `model` is the instantiated model object.
+ *         // If there was an error, this function would be skipped.
+ *     }
+ * ], callback);
+ *
+ * // es6 example
+ * var q = async.queue(async.asyncify(async function(file) {
+ *     var intermediateStep = await processFile(file);
+ *     return await somePromise(intermediateStep)
+ * }));
+ *
+ * q.push(files);
+ */
+function asyncify(func) {
+    return initialParams(function (args, callback) {
+        var result;
+        try {
+            result = func.apply(this, args);
+        } catch (e) {
+            return callback(e);
+        }
+        // if result is Promise object
+        if (isObject(result) && typeof result.then === 'function') {
+            result.then(function (value) {
+                callback(null, value);
+            }, function (err) {
+                callback(err.message ? err : new Error(err));
+            });
+        } else {
+            callback(null, result);
+        }
+    });
+}
+
+/**
+ * A specialized version of `_.forEach` for arrays without support for
+ * iteratee shorthands.
+ *
+ * @private
+ * @param {Array} [array] The array to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @returns {Array} Returns `array`.
+ */
+function arrayEach(array, iteratee) {
+  var index = -1,
+      length = array == null ? 0 : array.length;
+
+  while (++index < length) {
+    if (iteratee(array[index], index, array) === false) {
+      break;
+    }
+  }
+  return array;
+}
+
+/**
+ * Creates a base function for methods like `_.forIn` and `_.forOwn`.
+ *
+ * @private
+ * @param {boolean} [fromRight] Specify iterating from right to left.
+ * @returns {Function} Returns the new base function.
+ */
+function createBaseFor(fromRight) {
+  return function(object, iteratee, keysFunc) {
+    var index = -1,
+        iterable = Object(object),
+        props = keysFunc(object),
+        length = props.length;
+
+    while (length--) {
+      var key = props[fromRight ? length : ++index];
+      if (iteratee(iterable[key], key, iterable) === false) {
+        break;
+      }
+    }
+    return object;
+  };
+}
+
+/**
+ * The base implementation of `baseForOwn` which iterates over `object`
+ * properties returned by `keysFunc` and invokes `iteratee` for each property.
+ * Iteratee functions may exit iteration early by explicitly returning `false`.
+ *
+ * @private
+ * @param {Object} object The object to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @param {Function} keysFunc The function to get the keys of `object`.
+ * @returns {Object} Returns `object`.
+ */
+var baseFor = createBaseFor();
+
+/**
+ * The base implementation of `_.forOwn` without support for iteratee shorthands.
+ *
+ * @private
+ * @param {Object} object The object to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @returns {Object} Returns `object`.
+ */
+function baseForOwn(object, iteratee) {
+  return object && baseFor(object, iteratee, keys);
+}
+
+/**
+ * The base implementation of `_.findIndex` and `_.findLastIndex` without
+ * support for iteratee shorthands.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {Function} predicate The function invoked per iteration.
+ * @param {number} fromIndex The index to search from.
+ * @param {boolean} [fromRight] Specify iterating from right to left.
+ * @returns {number} Returns the index of the matched value, else `-1`.
+ */
+function baseFindIndex(array, predicate, fromIndex, fromRight) {
+  var length = array.length,
+      index = fromIndex + (fromRight ? 1 : -1);
+
+  while ((fromRight ? index-- : ++index < length)) {
+    if (predicate(array[index], index, array)) {
+      return index;
+    }
+  }
+  return -1;
+}
+
+/**
+ * The base implementation of `_.isNaN` without support for number objects.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
+ */
+function baseIsNaN(value) {
+  return value !== value;
+}
+
+/**
+ * A specialized version of `_.indexOf` which performs strict equality
+ * comparisons of values, i.e. `===`.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {*} value The value to search for.
+ * @param {number} fromIndex The index to search from.
+ * @returns {number} Returns the index of the matched value, else `-1`.
+ */
+function strictIndexOf(array, value, fromIndex) {
+  var index = fromIndex - 1,
+      length = array.length;
+
+  while (++index < length) {
+    if (array[index] === value) {
+      return index;
+    }
+  }
+  return -1;
+}
+
+/**
+ * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {*} value The value to search for.
+ * @param {number} fromIndex The index to search from.
+ * @returns {number} Returns the index of the matched value, else `-1`.
+ */
+function baseIndexOf(array, value, fromIndex) {
+  return value === value
+    ? strictIndexOf(array, value, fromIndex)
+    : baseFindIndex(array, baseIsNaN, fromIndex);
+}
+
+/**
+ * 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, the `auto` sequence
+ * will stop. Further tasks will not execute (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 as the first argument, if they have dependencies. If a
+ * task function has no dependencies, it will only be passed a callback.
+ *
+ * @name auto
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Object} tasks - An object. Each of its properties is either a
+ * function or an array of requirements, with the function itself the last item
+ * in the array. The object's key of a property serves as the name of the task
+ * defined by that property, i.e. can be used when specifying requirements for
+ * other tasks. The function receives one or two arguments:
+ * * a `results` object, containing the results of the previously executed
+ *   functions, only passed if the task has any dependencies,
+ * * a `callback(err, result)` function, which must be called when finished,
+ *   passing an `error` (which can be `null`) and the result of the function's
+ *   execution.
+ * @param {number} [concurrency=Infinity] - An optional `integer` for
+ * determining the maximum number of tasks that can be run in parallel. By
+ * default, as many as possible.
+ * @param {Function} [callback] - 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 an
+ * error occurs, no further `tasks` will be performed, and the results object
+ * will only contain partial results. Invoked with (err, results).
+ * @returns undefined
+ * @example
+ *
+ * async.auto({
+ *     // this function will just be passed a callback
+ *     readData: async.apply(fs.readFile, 'data.txt', 'utf-8'),
+ *     showData: ['readData', function(results, cb) {
+ *         // results.readData is the file's contents
+ *         // ...
+ *     }]
+ * }, callback);
+ *
+ * async.auto({
+ *     get_data: function(callback) {
+ *         console.log('in get_data');
+ *         // async code to get some data
+ *         callback(null, 'data', 'converted to array');
+ *     },
+ *     make_folder: function(callback) {
+ *         console.log('in make_folder');
+ *         // async code to create a directory to store a file in
+ *         // this is run at the same time as getting the data
+ *         callback(null, 'folder');
+ *     },
+ *     write_file: ['get_data', 'make_folder', function(results, callback) {
+ *         console.log('in write_file', JSON.stringify(results));
+ *         // once there is some data and the directory exists,
+ *         // write the data to a file in the directory
+ *         callback(null, 'filename');
+ *     }],
+ *     email_link: ['write_file', function(results, callback) {
+ *         console.log('in email_link', JSON.stringify(results));
+ *         // once the file is written let's email a link to it...
+ *         // results.write_file contains the filename returned by write_file.
+ *         callback(null, {'file':results.write_file, 'email':'user@example.com'});
+ *     }]
+ * }, function(err, results) {
+ *     console.log('err = ', err);
+ *     console.log('results = ', results);
+ * });
+ */
+var auto = function (tasks, concurrency, callback) {
+    if (typeof concurrency === 'function') {
+        // concurrency is optional, shift the args.
+        callback = concurrency;
+        concurrency = null;
+    }
+    callback = once(callback || noop);
+    var keys$$1 = keys(tasks);
+    var numTasks = keys$$1.length;
+    if (!numTasks) {
+        return callback(null);
+    }
+    if (!concurrency) {
+        concurrency = numTasks;
+    }
+
+    var results = {};
+    var runningTasks = 0;
+    var hasError = false;
+
+    var listeners = {};
+
+    var readyTasks = [];
+
+    // for cycle detection:
+    var readyToCheck = []; // tasks that have been identified as reachable
+    // without the possibility of returning to an ancestor task
+    var uncheckedDependencies = {};
+
+    baseForOwn(tasks, function (task, key) {
+        if (!isArray(task)) {
+            // no dependencies
+            enqueueTask(key, [task]);
+            readyToCheck.push(key);
+            return;
+        }
+
+        var dependencies = task.slice(0, task.length - 1);
+        var remainingDependencies = dependencies.length;
+        if (remainingDependencies === 0) {
+            enqueueTask(key, task);
+            readyToCheck.push(key);
+            return;
+        }
+        uncheckedDependencies[key] = remainingDependencies;
+
+        arrayEach(dependencies, function (dependencyName) {
+            if (!tasks[dependencyName]) {
+                throw new Error('async.auto task `' + key + '` has a non-existent dependency in ' + dependencies.join(', '));
+            }
+            addListener(dependencyName, function () {
+                remainingDependencies--;
+                if (remainingDependencies === 0) {
+                    enqueueTask(key, task);
+                }
+            });
+        });
+    });
+
+    checkForDeadlocks();
+    processQueue();
+
+    function enqueueTask(key, task) {
+        readyTasks.push(function () {
+            runTask(key, task);
+        });
+    }
+
+    function processQueue() {
+        if (readyTasks.length === 0 && runningTasks === 0) {
+            return callback(null, results);
+        }
+        while (readyTasks.length && runningTasks < concurrency) {
+            var run = readyTasks.shift();
+            run();
+        }
+    }
+
+    function addListener(taskName, fn) {
+        var taskListeners = listeners[taskName];
+        if (!taskListeners) {
+            taskListeners = listeners[taskName] = [];
+        }
+
+        taskListeners.push(fn);
+    }
+
+    function taskComplete(taskName) {
+        var taskListeners = listeners[taskName] || [];
+        arrayEach(taskListeners, function (fn) {
+            fn();
+        });
+        processQueue();
+    }
+
+    function runTask(key, task) {
+        if (hasError) return;
+
+        var taskCallback = onlyOnce(rest(function (err, args) {
+            runningTasks--;
+            if (args.length <= 1) {
+                args = args[0];
+            }
+            if (err) {
+                var safeResults = {};
+                baseForOwn(results, function (val, rkey) {
+                    safeResults[rkey] = val;
+                });
+                safeResults[key] = args;
+                hasError = true;
+                listeners = [];
+
+                callback(err, safeResults);
+            } else {
+                results[key] = args;
+                taskComplete(key);
+            }
+        }));
+
+        runningTasks++;
+        var taskFn = task[task.length - 1];
+        if (task.length > 1) {
+            taskFn(results, taskCallback);
+        } else {
+            taskFn(taskCallback);
+        }
+    }
+
+    function checkForDeadlocks() {
+        // Kahn's algorithm
+        // https://en.wikipedia.org/wiki/Topological_sorting#Kahn.27s_algorithm
+        // http://connalle.blogspot.com/2013/10/topological-sortingkahn-algorithm.html
+        var currentTask;
+        var counter = 0;
+        while (readyToCheck.length) {
+            currentTask = readyToCheck.pop();
+            counter++;
+            arrayEach(getDependents(currentTask), function (dependent) {
+                if (--uncheckedDependencies[dependent] === 0) {
+                    readyToCheck.push(dependent);
+                }
+            });
+        }
+
+        if (counter !== numTasks) {
+            throw new Error('async.auto cannot execute tasks due to a recursive dependency');
+        }
+    }
+
+    function getDependents(taskName) {
+        var result = [];
+        baseForOwn(tasks, function (task, key) {
+            if (isArray(task) && baseIndexOf(task, taskName, 0) >= 0) {
+                result.push(key);
+            }
+        });
+        return result;
+    }
+};
+
+/**
+ * A specialized version of `_.map` for arrays without support for iteratee
+ * shorthands.
+ *
+ * @private
+ * @param {Array} [array] The array to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @returns {Array} Returns the new mapped array.
+ */
+function arrayMap(array, iteratee) {
+  var index = -1,
+      length = array == null ? 0 : array.length,
+      result = Array(length);
+
+  while (++index < length) {
+    result[index] = iteratee(array[index], index, array);
+  }
+  return result;
+}
+
+/** `Object#toString` result references. */
+var symbolTag = '[object Symbol]';
+
+/**
+ * Checks if `value` is classified as a `Symbol` primitive or object.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Lang
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
+ * @example
+ *
+ * _.isSymbol(Symbol.iterator);
+ * // => true
+ *
+ * _.isSymbol('abc');
+ * // => false
+ */
+function isSymbol(value) {
+  return typeof value == 'symbol' ||
+    (isObjectLike(value) && baseGetTag(value) == symbolTag);
+}
+
+/** Used as references for various `Number` constants. */
+var INFINITY = 1 / 0;
+
+/** Used to convert symbols to primitives and strings. */
+var symbolProto = Symbol$1 ? Symbol$1.prototype : undefined;
+var symbolToString = symbolProto ? symbolProto.toString : undefined;
+
+/**
+ * The base implementation of `_.toString` which doesn't convert nullish
+ * values to empty strings.
+ *
+ * @private
+ * @param {*} value The value to process.
+ * @returns {string} Returns the string.
+ */
+function baseToString(value) {
+  // Exit early for strings to avoid a performance hit in some environments.
+  if (typeof value == 'string') {
+    return value;
+  }
+  if (isArray(value)) {
+    // Recursively convert values (susceptible to call stack limits).
+    return arrayMap(value, baseToString) + '';
+  }
+  if (isSymbol(value)) {
+    return symbolToString ? symbolToString.call(value) : '';
+  }
+  var result = (value + '');
+  return (result == '0' && (1 / value) == -INFINITY) ? '-0' : result;
+}
+
+/**
+ * The base implementation of `_.slice` without an iteratee call guard.
+ *
+ * @private
+ * @param {Array} array The array to slice.
+ * @param {number} [start=0] The start position.
+ * @param {number} [end=array.length] The end position.
+ * @returns {Array} Returns the slice of `array`.
+ */
+function baseSlice(array, start, end) {
+  var index = -1,
+      length = array.length;
+
+  if (start < 0) {
+    start = -start > length ? 0 : (length + start);
+  }
+  end = end > length ? length : end;
+  if (end < 0) {
+    end += length;
+  }
+  length = start > end ? 0 : ((end - start) >>> 0);
+  start >>>= 0;
+
+  var result = Array(length);
+  while (++index < length) {
+    result[index] = array[index + start];
+  }
+  return result;
+}
+
+/**
+ * Casts `array` to a slice if it's needed.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {number} start The start position.
+ * @param {number} [end=array.length] The end position.
+ * @returns {Array} Returns the cast slice.
+ */
+function castSlice(array, start, end) {
+  var length = array.length;
+  end = end === undefined ? length : end;
+  return (!start && end >= length) ? array : baseSlice(array, start, end);
+}
+
+/**
+ * Used by `_.trim` and `_.trimEnd` to get the index of the last string symbol
+ * that is not found in the character symbols.
+ *
+ * @private
+ * @param {Array} strSymbols The string symbols to inspect.
+ * @param {Array} chrSymbols The character symbols to find.
+ * @returns {number} Returns the index of the last unmatched string symbol.
+ */
+function charsEndIndex(strSymbols, chrSymbols) {
+  var index = strSymbols.length;
+
+  while (index-- && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
+  return index;
+}
+
+/**
+ * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol
+ * that is not found in the character symbols.
+ *
+ * @private
+ * @param {Array} strSymbols The string symbols to inspect.
+ * @param {Array} chrSymbols The character symbols to find.
+ * @returns {number} Returns the index of the first unmatched string symbol.
+ */
+function charsStartIndex(strSymbols, chrSymbols) {
+  var index = -1,
+      length = strSymbols.length;
+
+  while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
+  return index;
+}
+
+/**
+ * Converts an ASCII `string` to an array.
+ *
+ * @private
+ * @param {string} string The string to convert.
+ * @returns {Array} Returns the converted array.
+ */
+function asciiToArray(string) {
+  return string.split('');
+}
+
+/** Used to compose unicode character classes. */
+var rsAstralRange = '\\ud800-\\udfff';
+var rsComboMarksRange = '\\u0300-\\u036f\\ufe20-\\ufe23';
+var rsComboSymbolsRange = '\\u20d0-\\u20f0';
+var rsVarRange = '\\ufe0e\\ufe0f';
+
+/** Used to compose unicode capture groups. */
+var rsZWJ = '\\u200d';
+
+/** Used to detect strings with [zero-width joiners or code points from the astral planes](http://eev.ee/blog/2015/09/12/dark-corners-of-unicode/). */
+var reHasUnicode = RegExp('[' + rsZWJ + rsAstralRange  + rsComboMarksRange + rsComboSymbolsRange + rsVarRange + ']');
+
+/**
+ * Checks if `string` contains Unicode symbols.
+ *
+ * @private
+ * @param {string} string The string to inspect.
+ * @returns {boolean} Returns `true` if a symbol is found, else `false`.
+ */
+function hasUnicode(string) {
+  return reHasUnicode.test(string);
+}
+
+/** Used to compose unicode character classes. */
+var rsAstralRange$1 = '\\ud800-\\udfff';
+var rsComboMarksRange$1 = '\\u0300-\\u036f\\ufe20-\\ufe23';
+var rsComboSymbolsRange$1 = '\\u20d0-\\u20f0';
+var rsVarRange$1 = '\\ufe0e\\ufe0f';
+
+/** Used to compose unicode capture groups. */
+var rsAstral = '[' + rsAstralRange$1 + ']';
+var rsCombo = '[' + rsComboMarksRange$1 + rsComboSymbolsRange$1 + ']';
+var rsFitz = '\\ud83c[\\udffb-\\udfff]';
+var rsModifier = '(?:' + rsCombo + '|' + rsFitz + ')';
+var rsNonAstral = '[^' + rsAstralRange$1 + ']';
+var rsRegional = '(?:\\ud83c[\\udde6-\\uddff]){2}';
+var rsSurrPair = '[\\ud800-\\udbff][\\udc00-\\udfff]';
+var rsZWJ$1 = '\\u200d';
+
+/** Used to compose unicode regexes. */
+var reOptMod = rsModifier + '?';
+var rsOptVar = '[' + rsVarRange$1 + ']?';
+var rsOptJoin = '(?:' + rsZWJ$1 + '(?:' + [rsNonAstral, rsRegional, rsSurrPair].join('|') + ')' + rsOptVar + reOptMod + ')*';
+var rsSeq = rsOptVar + reOptMod + rsOptJoin;
+var rsSymbol = '(?:' + [rsNonAstral + rsCombo + '?', rsCombo, rsRegional, rsSurrPair, rsAstral].join('|') + ')';
+
+/** Used to match [string symbols](https://mathiasbynens.be/notes/javascript-unicode). */
+var reUnicode = RegExp(rsFitz + '(?=' + rsFitz + ')|' + rsSymbol + rsSeq, 'g');
+
+/**
+ * Converts a Unicode `string` to an array.
+ *
+ * @private
+ * @param {string} string The string to convert.
+ * @returns {Array} Returns the converted array.
+ */
+function unicodeToArray(string) {
+  return string.match(reUnicode) || [];
+}
+
+/**
+ * Converts `string` to an array.
+ *
+ * @private
+ * @param {string} string The string to convert.
+ * @returns {Array} Returns the converted array.
+ */
+function stringToArray(string) {
+  return hasUnicode(string)
+    ? unicodeToArray(string)
+    : asciiToArray(string);
+}
+
+/**
+ * Converts `value` to a string. An empty string is returned for `null`
+ * and `undefined` values. The sign of `-0` is preserved.
+ *
+ * @static
+ * @memberOf _
+ * @since 4.0.0
+ * @category Lang
+ * @param {*} value The value to convert.
+ * @returns {string} Returns the converted string.
+ * @example
+ *
+ * _.toString(null);
+ * // => ''
+ *
+ * _.toString(-0);
+ * // => '-0'
+ *
+ * _.toString([1, 2, 3]);
+ * // => '1,2,3'
+ */
+function toString(value) {
+  return value == null ? '' : baseToString(value);
+}
+
+/** Used to match leading and trailing whitespace. */
+var reTrim = /^\s+|\s+$/g;
+
+/**
+ * Removes leading and trailing whitespace or specified characters from `string`.
+ *
+ * @static
+ * @memberOf _
+ * @since 3.0.0
+ * @category String
+ * @param {string} [string=''] The string to trim.
+ * @param {string} [chars=whitespace] The characters to trim.
+ * @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
+ * @returns {string} Returns the trimmed string.
+ * @example
+ *
+ * _.trim('  abc  ');
+ * // => 'abc'
+ *
+ * _.trim('-_-abc-_-', '_-');
+ * // => 'abc'
+ *
+ * _.map(['  foo  ', '  bar  '], _.trim);
+ * // => ['foo', 'bar']
+ */
+function trim(string, chars, guard) {
+  string = toString(string);
+  if (string && (guard || chars === undefined)) {
+    return string.replace(reTrim, '');
+  }
+  if (!string || !(chars = baseToString(chars))) {
+    return string;
+  }
+  var strSymbols = stringToArray(string),
+      chrSymbols = stringToArray(chars),
+      start = charsStartIndex(strSymbols, chrSymbols),
+      end = charsEndIndex(strSymbols, chrSymbols) + 1;
+
+  return castSlice(strSymbols, start, end).join('');
+}
+
+var FN_ARGS = /^(function)?\s*[^\(]*\(\s*([^\)]*)\)/m;
+var FN_ARG_SPLIT = /,/;
+var FN_ARG = /(=.+)?(\s*)$/;
+var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
+
+function parseParams(func) {
+    func = func.toString().replace(STRIP_COMMENTS, '');
+    func = func.match(FN_ARGS)[2].replace(' ', '');
+    func = func ? func.split(FN_ARG_SPLIT) : [];
+    func = func.map(function (arg) {
+        return trim(arg.replace(FN_ARG, ''));
+    });
+    return func;
+}
+
+/**
+ * A dependency-injected version of the [async.auto]{@link module:ControlFlow.auto} function. Dependent
+ * tasks are specified as parameters to the function, after the usual callback
+ * parameter, with the parameter names matching the names of the tasks it
+ * depends on. This can provide even more readable task graphs which can be
+ * easier to maintain.
+ *
+ * If a final callback is specified, the task results are similarly injected,
+ * specified as named parameters after the initial error parameter.
+ *
+ * The autoInject function is purely syntactic sugar and its semantics are
+ * otherwise equivalent to [async.auto]{@link module:ControlFlow.auto}.
+ *
+ * @name autoInject
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.auto]{@link module:ControlFlow.auto}
+ * @category Control Flow
+ * @param {Object} tasks - An object, each of whose properties is a function of
+ * the form 'func([dependencies...], callback). The object's key of a property
+ * serves as the name of the task defined by that property, i.e. can be used
+ * when specifying requirements for other tasks.
+ * * The `callback` parameter is 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. The remaining parameters name other tasks on
+ *   which the task is dependent, and the results from those tasks are the
+ *   arguments of those parameters.
+ * @param {Function} [callback] - 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, and a `results` object with any completed
+ * task results, similar to `auto`.
+ * @example
+ *
+ * //  The example from `auto` can be rewritten as follows:
+ * async.autoInject({
+ *     get_data: function(callback) {
+ *         // async code to get some data
+ *         callback(null, 'data', 'converted to array');
+ *     },
+ *     make_folder: function(callback) {
+ *         // async code to create a directory to store a file in
+ *         // this is run at the same time as getting the data
+ *         callback(null, 'folder');
+ *     },
+ *     write_file: function(get_data, make_folder, callback) {
+ *         // once there is some data and the directory exists,
+ *         // write the data to a file in the directory
+ *         callback(null, 'filename');
+ *     },
+ *     email_link: function(write_file, callback) {
+ *         // once the file is written let's email a link to it...
+ *         // write_file contains the filename returned by write_file.
+ *         callback(null, {'file':write_file, 'email':'user@example.com'});
+ *     }
+ * }, function(err, results) {
+ *     console.log('err = ', err);
+ *     console.log('email_link = ', results.email_link);
+ * });
+ *
+ * // If you are using a JS minifier that mangles parameter names, `autoInject`
+ * // will not work with plain functions, since the parameter names will be
+ * // collapsed to a single letter identifier.  To work around this, you can
+ * // explicitly specify the names of the parameters your task function needs
+ * // in an array, similar to Angular.js dependency injection.
+ *
+ * // This still has an advantage over plain `auto`, since the results a task
+ * // depends on are still spread into arguments.
+ * async.autoInject({
+ *     //...
+ *     write_file: ['get_data', 'make_folder', function(get_data, make_folder, callback) {
+ *         callback(null, 'filename');
+ *     }],
+ *     email_link: ['write_file', function(write_file, callback) {
+ *         callback(null, {'file':write_file, 'email':'user@example.com'});
+ *     }]
+ *     //...
+ * }, function(err, results) {
+ *     console.log('err = ', err);
+ *     console.log('email_link = ', results.email_link);
+ * });
+ */
+function autoInject(tasks, callback) {
+    var newTasks = {};
+
+    baseForOwn(tasks, function (taskFn, key) {
+        var params;
+
+        if (isArray(taskFn)) {
+            params = taskFn.slice(0, -1);
+            taskFn = taskFn[taskFn.length - 1];
+
+            newTasks[key] = params.concat(params.length > 0 ? newTask : taskFn);
+        } else if (taskFn.length === 1) {
+            // no dependencies, use the function as-is
+            newTasks[key] = taskFn;
+        } else {
+            params = parseParams(taskFn);
+            if (taskFn.length === 0 && params.length === 0) {
+                throw new Error("autoInject task functions require explicit parameters.");
+            }
+
+            params.pop();
+
+            newTasks[key] = params.concat(newTask);
+        }
+
+        function newTask(results, taskCb) {
+            var newArgs = arrayMap(params, function (name) {
+                return results[name];
+            });
+            newArgs.push(taskCb);
+            taskFn.apply(null, newArgs);
+        }
+    });
+
+    auto(newTasks, callback);
+}
+
+var hasSetImmediate = typeof setImmediate === 'function' && setImmediate;
+var hasNextTick = typeof process === 'object' && typeof process.nextTick === 'function';
+
+function fallback(fn) {
+    setTimeout(fn, 0);
+}
+
+function wrap(defer) {
+    return rest(function (fn, args) {
+        defer(function () {
+            fn.apply(null, args);
+        });
+    });
+}
+
+var _defer;
+
+if (hasSetImmediate) {
+    _defer = setImmediate;
+} else if (hasNextTick) {
+    _defer = process.nextTick;
+} else {
+    _defer = fallback;
+}
+
+var setImmediate$1 = wrap(_defer);
+
+// Simple doubly linked list (https://en.wikipedia.org/wiki/Doubly_linked_list) implementation
+// used for queues. This implementation assumes that the node provided by the user can be modified
+// to adjust the next and last properties. We implement only the minimal functionality
+// for queue support.
+function DLL() {
+    this.head = this.tail = null;
+    this.length = 0;
+}
+
+function setInitial(dll, node) {
+    dll.length = 1;
+    dll.head = dll.tail = node;
+}
+
+DLL.prototype.removeLink = function (node) {
+    if (node.prev) node.prev.next = node.next;else this.head = node.next;
+    if (node.next) node.next.prev = node.prev;else this.tail = node.prev;
+
+    node.prev = node.next = null;
+    this.length -= 1;
+    return node;
+};
+
+DLL.prototype.empty = DLL;
+
+DLL.prototype.insertAfter = function (node, newNode) {
+    newNode.prev = node;
+    newNode.next = node.next;
+    if (node.next) node.next.prev = newNode;else this.tail = newNode;
+    node.next = newNode;
+    this.length += 1;
+};
+
+DLL.prototype.insertBefore = function (node, newNode) {
+    newNode.prev = node.prev;
+    newNode.next = node;
+    if (node.prev) node.prev.next = newNode;else this.head = newNode;
+    node.prev = newNode;
+    this.length += 1;
+};
+
+DLL.prototype.unshift = function (node) {
+    if (this.head) this.insertBefore(this.head, node);else setInitial(this, node);
+};
+
+DLL.prototype.push = function (node) {
+    if (this.tail) this.insertAfter(this.tail, node);else setInitial(this, node);
+};
+
+DLL.prototype.shift = function () {
+    return this.head && this.removeLink(this.head);
+};
+
+DLL.prototype.pop = function () {
+    return this.tail && this.removeLink(this.tail);
+};
+
+function queue(worker, concurrency, payload) {
+    if (concurrency == null) {
+        concurrency = 1;
+    } else if (concurrency === 0) {
+        throw new Error('Concurrency must not be zero');
+    }
+
+    function _insert(data, insertAtFront, callback) {
+        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 && q.idle()) {
+            // call drain immediately if there are no tasks
+            return setImmediate$1(function () {
+                q.drain();
+            });
+        }
+
+        for (var i = 0, l = data.length; i < l; i++) {
+            var item = {
+                data: data[i],
+                callback: callback || noop
+            };
+
+            if (insertAtFront) {
+                q._tasks.unshift(item);
+            } else {
+                q._tasks.push(item);
+            }
+        }
+        setImmediate$1(q.process);
+    }
+
+    function _next(tasks) {
+        return rest(function (args) {
+            workers -= 1;
+
+            for (var i = 0, l = tasks.length; i < l; i++) {
+                var task = tasks[i];
+                var index = baseIndexOf(workersList, task, 0);
+                if (index >= 0) {
+                    workersList.splice(index);
+                }
+
+                task.callback.apply(task, args);
+
+                if (args[0] != null) {
+                    q.error(args[0], task.data);
+                }
+            }
+
+            if (workers <= q.concurrency - q.buffer) {
+                q.unsaturated();
+            }
+
+            if (q.idle()) {
+                q.drain();
+            }
+            q.process();
+        });
+    }
+
+    var workers = 0;
+    var workersList = [];
+    var q = {
+        _tasks: new DLL(),
+        concurrency: concurrency,
+        payload: payload,
+        saturated: noop,
+        unsaturated: noop,
+        buffer: concurrency / 4,
+        empty: noop,
+        drain: noop,
+        error: noop,
+        started: false,
+        paused: false,
+        push: function (data, callback) {
+            _insert(data, false, callback);
+        },
+        kill: function () {
+            q.drain = noop;
+            q._tasks.empty();
+        },
+        unshift: function (data, callback) {
+            _insert(data, true, callback);
+        },
+        process: function () {
+            while (!q.paused && workers < q.concurrency && q._tasks.length) {
+                var tasks = [],
+                    data = [];
+                var l = q._tasks.length;
+                if (q.payload) l = Math.min(l, q.payload);
+                for (var i = 0; i < l; i++) {
+                    var node = q._tasks.shift();
+                    tasks.push(node);
+                    data.push(node.data);
+                }
+
+                if (q._tasks.length === 0) {
+                    q.empty();
+                }
+                workers += 1;
+                workersList.push(tasks[0]);
+
+                if (workers === q.concurrency) {
+                    q.saturated();
+                }
+
+                var cb = onlyOnce(_next(tasks));
+                worker(data, cb);
+            }
+        },
+        length: function () {
+            return q._tasks.length;
+        },
+        running: function () {
+            return workers;
+        },
+        workersList: function () {
+            return workersList;
+        },
+        idle: function () {
+            return q._tasks.length + workers === 0;
+        },
+        pause: function () {
+            q.paused = true;
+        },
+        resume: function () {
+            if (q.paused === false) {
+                return;
+            }
+            q.paused = false;
+            var resumeCount = Math.min(q.concurrency, q._tasks.length);
+            // Need to call q.process once per concurrent
+            // worker to preserve full concurrency after pause
+            for (var w = 1; w <= resumeCount; w++) {
+                setImmediate$1(q.process);
+            }
+        }
+    };
+    return q;
+}
+
+/**
+ * A cargo of tasks for the worker function to complete. Cargo inherits all of
+ * the same methods and event callbacks as [`queue`]{@link module:ControlFlow.queue}.
+ * @typedef {Object} CargoObject
+ * @memberOf module:ControlFlow
+ * @property {Function} length - A function returning the number of items
+ * waiting to be processed. Invoke like `cargo.length()`.
+ * @property {number} payload - An `integer` for determining how many tasks
+ * should be process per round. This property can be changed after a `cargo` is
+ * created to alter the payload on-the-fly.
+ * @property {Function} push - 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` can be submitted. The respective callback is
+ * used for every task in the list. Invoke like `cargo.push(task, [callback])`.
+ * @property {Function} saturated - A callback that is called when the
+ * `queue.length()` hits the concurrency and further tasks will be queued.
+ * @property {Function} empty - A callback that is called when the last item
+ * from the `queue` is given to a `worker`.
+ * @property {Function} drain - A callback that is called when the last item
+ * from the `queue` has returned from the `worker`.
+ * @property {Function} idle - a function returning false if there are items
+ * waiting or being processed, or true if not. Invoke like `cargo.idle()`.
+ * @property {Function} pause - a function that pauses the processing of tasks
+ * until `resume()` is called. Invoke like `cargo.pause()`.
+ * @property {Function} resume - a function that resumes the processing of
+ * queued tasks when the queue is paused. Invoke like `cargo.resume()`.
+ * @property {Function} kill - a function that removes the `drain` callback and
+ * empties remaining tasks from the queue forcing it to go idle. Invoke like `cargo.kill()`.
+ */
+
+/**
+ * Creates a `cargo` object with the specified payload. Tasks added to the
+ * cargo will be processed altogether (up to the `payload` limit). If the
+ * `worker` is in progress, the task is queued until it becomes available. Once
+ * the `worker` has completed some tasks, each callback of those tasks is
+ * called. Check out [these](https://camo.githubusercontent.com/6bbd36f4cf5b35a0f11a96dcd2e97711ffc2fb37/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130382f62626330636662302d356632392d313165322d393734662d3333393763363464633835382e676966) [animations](https://camo.githubusercontent.com/f4810e00e1c5f5f8addbe3e9f49064fd5d102699/68747470733a2f2f662e636c6f75642e6769746875622e636f6d2f6173736574732f313637363837312f36383130312f38346339323036362d356632392d313165322d383134662d3964336430323431336266642e676966)
+ * for how `cargo` and `queue` work.
+ *
+ * While [`queue`]{@link module:ControlFlow.queue} passes only one task to one of a group of workers
+ * at a time, cargo passes an array of tasks to a single worker, repeating
+ * when the worker is finished.
+ *
+ * @name cargo
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.queue]{@link module:ControlFlow.queue}
+ * @category Control Flow
+ * @param {Function} worker - An asynchronous function for processing an array
+ * of queued tasks, which must call its `callback(err)` argument when finished,
+ * with an optional `err` argument. Invoked with `(tasks, callback)`.
+ * @param {number} [payload=Infinity] - An optional `integer` for determining
+ * how many tasks should be processed per round; if omitted, the default is
+ * unlimited.
+ * @returns {module:ControlFlow.CargoObject} A cargo object to manage the tasks. Callbacks can
+ * attached as certain properties to listen for specific events during the
+ * lifecycle of the cargo and inner queue.
+ * @example
+ *
+ * // create a cargo object with payload 2
+ * var cargo = async.cargo(function(tasks, callback) {
+ *     for (var i=0; i<tasks.length; i++) {
+ *         console.log('hello ' + tasks[i].name);
+ *     }
+ *     callback();
+ * }, 2);
+ *
+ * // add some items
+ * cargo.push({name: 'foo'}, function(err) {
+ *     console.log('finished processing foo');
+ * });
+ * cargo.push({name: 'bar'}, function(err) {
+ *     console.log('finished processing bar');
+ * });
+ * cargo.push({name: 'baz'}, function(err) {
+ *     console.log('finished processing baz');
+ * });
+ */
+function cargo(worker, payload) {
+  return queue(worker, 1, payload);
+}
+
+/**
+ * The same as [`eachOf`]{@link module:Collections.eachOf} but runs only a single async operation at a time.
+ *
+ * @name eachOfSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.eachOf]{@link module:Collections.eachOf}
+ * @alias forEachOfSeries
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`. The
+ * `key` is the item's key, or index in the case of an array. The iteratee 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. Invoked with (item, key, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. Invoked with (err).
+ */
+var eachOfSeries = doLimit(eachOfLimit, 1);
+
+/**
+ * Reduces `coll` into a single value using an async `iteratee` to return 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; if you can get the data before reducing it, then it's
+ * probably a good idea to do so.
+ *
+ * @name reduce
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias inject
+ * @alias foldl
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {*} memo - The initial state of the reduction.
+ * @param {Function} iteratee - A function applied to each item in the
+ * array to produce the next step in the reduction. The `iteratee` 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
+ * immediately called with the error. Invoked with (memo, item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result is the reduced value. Invoked with
+ * (err, result).
+ * @example
+ *
+ * async.reduce([1,2,3], 0, function(memo, item, callback) {
+ *     // pointless async:
+ *     process.nextTick(function() {
+ *         callback(null, memo + item)
+ *     });
+ * }, function(err, result) {
+ *     // result is now equal to the last value of memo, which is 6
+ * });
+ */
+function reduce(coll, memo, iteratee, callback) {
+    callback = once(callback || noop);
+    eachOfSeries(coll, function (x, i, callback) {
+        iteratee(memo, x, function (err, v) {
+            memo = v;
+            callback(err);
+        });
+    }, function (err) {
+        callback(err, memo);
+    });
+}
+
+/**
+ * Version of the compose function that is more natural to read. Each function
+ * consumes the return value of the previous function. It is the equivalent of
+ * [compose]{@link module:ControlFlow.compose} with the arguments reversed.
+ *
+ * Each function is executed with the `this` binding of the composed function.
+ *
+ * @name seq
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.compose]{@link module:ControlFlow.compose}
+ * @category Control Flow
+ * @param {...Function} functions - the asynchronous functions to compose
+ * @returns {Function} a function that composes the `functions` in order
+ * @example
+ *
+ * // Requires lodash (or underscore), express3 and dresende's orm2.
+ * // Part of an app, that fetches cats of the logged user.
+ * // This example uses `seq` function to avoid overnesting and error
+ * // handling clutter.
+ * app.get('/cats', function(request, response) {
+ *     var User = request.models.User;
+ *     async.seq(
+ *         _.bind(User.get, User),  // 'User.get' has signature (id, callback(err, data))
+ *         function(user, fn) {
+ *             user.getCats(fn);      // 'getCats' has signature (callback(err, data))
+ *         }
+ *     )(req.session.user_id, function (err, cats) {
+ *         if (err) {
+ *             console.error(err);
+ *             response.json({ status: 'error', message: err.message });
+ *         } else {
+ *             response.json({ status: 'ok', message: 'Cats found', data: cats });
+ *         }
+ *     });
+ * });
+ */
+var seq$1 = rest(function seq(functions) {
+    return rest(function (args) {
+        var that = this;
+
+        var cb = args[args.length - 1];
+        if (typeof cb == 'function') {
+            args.pop();
+        } else {
+            cb = noop;
+        }
+
+        reduce(functions, args, function (newargs, fn, cb) {
+            fn.apply(that, newargs.concat(rest(function (err, nextargs) {
+                cb(err, nextargs);
+            })));
+        }, function (err, results) {
+            cb.apply(that, [err].concat(results));
+        });
+    });
+});
+
+/**
+ * Creates a function which is a composition of the passed asynchronous
+ * functions. Each function consumes the return value of the function that
+ * follows. Composing functions `f()`, `g()`, and `h()` would produce the result
+ * of `f(g(h()))`, only this version uses callbacks to obtain the return values.
+ *
+ * Each function is executed with the `this` binding of the composed function.
+ *
+ * @name compose
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {...Function} functions - the asynchronous functions to compose
+ * @returns {Function} an asynchronous function that is the composed
+ * asynchronous `functions`
+ * @example
+ *
+ * function add1(n, callback) {
+ *     setTimeout(function () {
+ *         callback(null, n + 1);
+ *     }, 10);
+ * }
+ *
+ * function mul3(n, callback) {
+ *     setTimeout(function () {
+ *         callback(null, n * 3);
+ *     }, 10);
+ * }
+ *
+ * var add1mul3 = async.compose(mul3, add1);
+ * add1mul3(4, function (err, result) {
+ *     // result now equals 15
+ * });
+ */
+var compose = rest(function (args) {
+  return seq$1.apply(null, args.reverse());
+});
+
+function concat$1(eachfn, arr, fn, callback) {
+    var result = [];
+    eachfn(arr, function (x, index, cb) {
+        fn(x, function (err, y) {
+            result = result.concat(y || []);
+            cb(err);
+        });
+    }, function (err) {
+        callback(err, result);
+    });
+}
+
+/**
+ * Applies `iteratee` to each item in `coll`, concatenating the results. Returns
+ * the concatenated list. The `iteratee`s are called in parallel, and the
+ * results are concatenated as they return. There is no guarantee that the
+ * results array will be returned in the original order of `coll` passed to the
+ * `iteratee` function.
+ *
+ * @name concat
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee 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.
+ * Invoked with (item, callback).
+ * @param {Function} [callback(err)] - A callback which is called after all the
+ * `iteratee` functions have finished, or an error occurs. Results is an array
+ * containing the concatenated results of the `iteratee` function. Invoked with
+ * (err, results).
+ * @example
+ *
+ * async.concat(['dir1','dir2','dir3'], fs.readdir, function(err, files) {
+ *     // files is now a list of filenames that exist in the 3 directories
+ * });
+ */
+var concat = doParallel(concat$1);
+
+function doSeries(fn) {
+    return function (obj, iteratee, callback) {
+        return fn(eachOfSeries, obj, iteratee, callback);
+    };
+}
+
+/**
+ * The same as [`concat`]{@link module:Collections.concat} but runs only a single async operation at a time.
+ *
+ * @name concatSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.concat]{@link module:Collections.concat}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee 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.
+ * Invoked with (item, callback).
+ * @param {Function} [callback(err)] - A callback which is called after all the
+ * `iteratee` functions have finished, or an error occurs. Results is an array
+ * containing the concatenated results of the `iteratee` function. Invoked with
+ * (err, results).
+ */
+var concatSeries = doSeries(concat$1);
+
+/**
+ * Returns a function that when called, calls-back with the values provided.
+ * Useful as the first function in a [`waterfall`]{@link module:ControlFlow.waterfall}, or for plugging values in to
+ * [`auto`]{@link module:ControlFlow.auto}.
+ *
+ * @name constant
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {...*} arguments... - Any number of arguments to automatically invoke
+ * callback with.
+ * @returns {Function} Returns a function that when invoked, automatically
+ * invokes the callback with the previous given arguments.
+ * @example
+ *
+ * async.waterfall([
+ *     async.constant(42),
+ *     function (value, next) {
+ *         // value === 42
+ *     },
+ *     //...
+ * ], callback);
+ *
+ * async.waterfall([
+ *     async.constant(filename, "utf8"),
+ *     fs.readFile,
+ *     function (fileData, next) {
+ *         //...
+ *     }
+ *     //...
+ * ], callback);
+ *
+ * async.auto({
+ *     hostname: async.constant("https://server.net/"),
+ *     port: findFreePort,
+ *     launchServer: ["hostname", "port", function (options, cb) {
+ *         startServer(options, cb);
+ *     }],
+ *     //...
+ * }, callback);
+ */
+var constant = rest(function (values) {
+    var args = [null].concat(values);
+    return initialParams(function (ignoredArgs, callback) {
+        return callback.apply(this, args);
+    });
+});
+
+function _createTester(eachfn, check, getResult) {
+    return function (arr, limit, iteratee, cb) {
+        function done() {
+            if (cb) {
+                cb(null, getResult(false));
+            }
+        }
+        function wrappedIteratee(x, _, callback) {
+            if (!cb) return callback();
+            iteratee(x, function (err, v) {
+                // Check cb as another iteratee may have resolved with a
+                // value or error since we started this iteratee
+                if (cb && (err || check(v))) {
+                    if (err) cb(err);else cb(err, getResult(true, x));
+                    cb = iteratee = false;
+                    callback(err, breakLoop);
+                } else {
+                    callback();
+                }
+            });
+        }
+        if (arguments.length > 3) {
+            cb = cb || noop;
+            eachfn(arr, limit, wrappedIteratee, done);
+        } else {
+            cb = iteratee;
+            cb = cb || noop;
+            iteratee = limit;
+            eachfn(arr, wrappedIteratee, done);
+        }
+    };
+}
+
+function _findGetResult(v, x) {
+    return x;
+}
+
+/**
+ * Returns the first value in `coll` that passes an async truth test. The
+ * `iteratee` is applied in parallel, meaning the first iteratee to return
+ * `true` will fire the detect `callback` with that result. That means the
+ * result might not be the first item in the original `coll` (in terms of order)
+ * that passes the test.
+
+ * If order within the original `coll` is important, then look at
+ * [`detectSeries`]{@link module:Collections.detectSeries}.
+ *
+ * @name detect
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias find
+ * @category Collections
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The iteratee is passed a `callback(err, truthValue)` which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the `iteratee` functions have finished.
+ * Result will be the first item in the array that passes the truth test
+ * (iteratee) or the value `undefined` if none passed. Invoked with
+ * (err, result).
+ * @example
+ *
+ * async.detect(['file1','file2','file3'], function(filePath, callback) {
+ *     fs.access(filePath, function(err) {
+ *         callback(null, !err)
+ *     });
+ * }, function(err, result) {
+ *     // result now equals the first file in the list that exists
+ * });
+ */
+var detect = _createTester(eachOf, identity, _findGetResult);
+
+/**
+ * The same as [`detect`]{@link module:Collections.detect} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name detectLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.detect]{@link module:Collections.detect}
+ * @alias findLimit
+ * @category Collections
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The iteratee is passed a `callback(err, truthValue)` which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the `iteratee` functions have finished.
+ * Result will be the first item in the array that passes the truth test
+ * (iteratee) or the value `undefined` if none passed. Invoked with
+ * (err, result).
+ */
+var detectLimit = _createTester(eachOfLimit, identity, _findGetResult);
+
+/**
+ * The same as [`detect`]{@link module:Collections.detect} but runs only a single async operation at a time.
+ *
+ * @name detectSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.detect]{@link module:Collections.detect}
+ * @alias findSeries
+ * @category Collections
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The iteratee is passed a `callback(err, truthValue)` which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the `iteratee` functions have finished.
+ * Result will be the first item in the array that passes the truth test
+ * (iteratee) or the value `undefined` if none passed. Invoked with
+ * (err, result).
+ */
+var detectSeries = _createTester(eachOfSeries, identity, _findGetResult);
+
+function consoleFunc(name) {
+    return rest(function (fn, args) {
+        fn.apply(null, args.concat(rest(function (err, args) {
+            if (typeof console === 'object') {
+                if (err) {
+                    if (console.error) {
+                        console.error(err);
+                    }
+                } else if (console[name]) {
+                    arrayEach(args, function (x) {
+                        console[name](x);
+                    });
+                }
+            }
+        })));
+    });
+}
+
+/**
+ * Logs the result of an `async` function to the `console` using `console.dir`
+ * to display the properties of the resulting object. Only works in Node.js or
+ * in browsers that support `console.dir` and `console.error` (such as FF and
+ * Chrome). If multiple arguments are returned from the async function,
+ * `console.dir` is called on each argument in order.
+ *
+ * @name dir
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} function - The function you want to eventually apply all
+ * arguments to.
+ * @param {...*} arguments... - Any number of arguments to apply to the function.
+ * @example
+ *
+ * // in a module
+ * var hello = function(name, callback) {
+ *     setTimeout(function() {
+ *         callback(null, {hello: name});
+ *     }, 1000);
+ * };
+ *
+ * // in the node repl
+ * node> async.dir(hello, 'world');
+ * {hello: 'world'}
+ */
+var dir = consoleFunc('dir');
+
+/**
+ * The post-check version of [`during`]{@link module:ControlFlow.during}. To reflect the difference in
+ * the order of operations, the arguments `test` and `fn` are switched.
+ *
+ * Also a version of [`doWhilst`]{@link module:ControlFlow.doWhilst} with asynchronous `test` function.
+ * @name doDuring
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.during]{@link module:ControlFlow.during}
+ * @category Control Flow
+ * @param {Function} fn - 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 optional `err` argument. Invoked with (callback).
+ * @param {Function} test - asynchronous truth test to perform before each
+ * execution of `fn`. Invoked with (...args, callback), where `...args` are the
+ * non-error args from the previous callback of `fn`.
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has failed and repeated execution of `fn` has stopped. `callback`
+ * will be passed an error if one occured, otherwise `null`.
+ */
+function doDuring(fn, test, callback) {
+    callback = onlyOnce(callback || noop);
+
+    var next = rest(function (err, args) {
+        if (err) return callback(err);
+        args.push(check);
+        test.apply(this, args);
+    });
+
+    function check(err, truth) {
+        if (err) return callback(err);
+        if (!truth) return callback(null);
+        fn(next);
+    }
+
+    check(null, true);
+}
+
+/**
+ * The post-check version of [`whilst`]{@link module:ControlFlow.whilst}. To reflect the difference in
+ * the order of operations, the arguments `test` and `iteratee` are switched.
+ *
+ * `doWhilst` is to `whilst` as `do while` is to `while` in plain JavaScript.
+ *
+ * @name doWhilst
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.whilst]{@link module:ControlFlow.whilst}
+ * @category Control Flow
+ * @param {Function} iteratee - 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 optional `err` argument. Invoked with (callback).
+ * @param {Function} test - synchronous truth test to perform after each
+ * execution of `iteratee`. Invoked with the non-error callback results of
+ * `iteratee`.
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has failed and repeated execution of `iteratee` has stopped.
+ * `callback` will be passed an error and any arguments passed to the final
+ * `iteratee`'s callback. Invoked with (err, [results]);
+ */
+function doWhilst(iteratee, test, callback) {
+    callback = onlyOnce(callback || noop);
+    var next = rest(function (err, args) {
+        if (err) return callback(err);
+        if (test.apply(this, args)) return iteratee(next);
+        callback.apply(null, [null].concat(args));
+    });
+    iteratee(next);
+}
+
+/**
+ * Like ['doWhilst']{@link module:ControlFlow.doWhilst}, except the `test` is inverted. Note the
+ * argument ordering differs from `until`.
+ *
+ * @name doUntil
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.doWhilst]{@link module:ControlFlow.doWhilst}
+ * @category Control Flow
+ * @param {Function} fn - A function which is called each time `test` fails.
+ * The function is passed a `callback(err)`, which must be called once it has
+ * completed with an optional `err` argument. Invoked with (callback).
+ * @param {Function} test - synchronous truth test to perform after each
+ * execution of `fn`. Invoked with the non-error callback results of `fn`.
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has passed and repeated execution of `fn` has stopped. `callback`
+ * will be passed an error and any arguments passed to the final `fn`'s
+ * callback. Invoked with (err, [results]);
+ */
+function doUntil(fn, test, callback) {
+    doWhilst(fn, function () {
+        return !test.apply(this, arguments);
+    }, callback);
+}
+
+/**
+ * Like [`whilst`]{@link module:ControlFlow.whilst}, except the `test` is an asynchronous function that
+ * is passed a callback in the form of `function (err, truth)`. If error is
+ * passed to `test` or `fn`, the main callback is immediately called with the
+ * value of the error.
+ *
+ * @name during
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.whilst]{@link module:ControlFlow.whilst}
+ * @category Control Flow
+ * @param {Function} test - asynchronous truth test to perform before each
+ * execution of `fn`. Invoked with (callback).
+ * @param {Function} fn - 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 optional `err` argument. Invoked with (callback).
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has failed and repeated execution of `fn` has stopped. `callback`
+ * will be passed an error, if one occured, otherwise `null`.
+ * @example
+ *
+ * var count = 0;
+ *
+ * async.during(
+ *     function (callback) {
+ *         return callback(null, count < 5);
+ *     },
+ *     function (callback) {
+ *         count++;
+ *         setTimeout(callback, 1000);
+ *     },
+ *     function (err) {
+ *         // 5 seconds have passed
+ *     }
+ * );
+ */
+function during(test, fn, callback) {
+    callback = onlyOnce(callback || noop);
+
+    function next(err) {
+        if (err) return callback(err);
+        test(check);
+    }
+
+    function check(err, truth) {
+        if (err) return callback(err);
+        if (!truth) return callback(null);
+        fn(next);
+    }
+
+    test(check);
+}
+
+function _withoutIndex(iteratee) {
+    return function (value, index, callback) {
+        return iteratee(value, callback);
+    };
+}
+
+/**
+ * Applies the function `iteratee` to each item in `coll`, in parallel.
+ * The `iteratee` is called with an item from the list, and a callback for when
+ * it has finished. If the `iteratee` passes an error to its `callback`, the
+ * main `callback` (for the `each` function) is immediately called with the
+ * error.
+ *
+ * Note, that since this function applies `iteratee` to each item in parallel,
+ * there is no guarantee that the iteratee functions will complete in order.
+ *
+ * @name each
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias forEach
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item
+ * in `coll`. The iteratee 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 iteratee. Invoked with (item, callback). 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).
+ * @example
+ *
+ * // assuming openFiles is an array of file names and saveFile is a function
+ * // to save the modified contents of that file:
+ *
+ * async.each(openFiles, saveFile, function(err){
+ *   // if any of the saves produced an error, err would equal that error
+ * });
+ *
+ * // 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 ) {
+ *       console.log('This file name is too long');
+ *       callback('File name too long');
+ *     } else {
+ *       // Do work to process file here
+ *       console.log('File processed');
+ *       callback();
+ *     }
+ * }, function(err) {
+ *     // if any of the file processing produced an error, err would equal that error
+ *     if( err ) {
+ *       // One of the iterations produced an error.
+ *       // All processing will now stop.
+ *       console.log('A file failed to process');
+ *     } else {
+ *       console.log('All files have been processed successfully');
+ *     }
+ * });
+ */
+function eachLimit(coll, iteratee, callback) {
+  eachOf(coll, _withoutIndex(iteratee), callback);
+}
+
+/**
+ * The same as [`each`]{@link module:Collections.each} but runs a maximum of `limit` async operations at a time.
+ *
+ * @name eachLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.each]{@link module:Collections.each}
+ * @alias forEachLimit
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A function to apply to each item in `coll`. The
+ * iteratee 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 iteratee. Invoked with (item, callback). If you need the index, use
+ * `eachOfLimit`.
+ * @param {Function} [callback] - A callback which is called when all
+ * `iteratee` functions have finished, or an error occurs. Invoked with (err).
+ */
+function eachLimit$1(coll, limit, iteratee, callback) {
+  _eachOfLimit(limit)(coll, _withoutIndex(iteratee), callback);
+}
+
+/**
+ * The same as [`each`]{@link module:Collections.each} but runs only a single async operation at a time.
+ *
+ * @name eachSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.each]{@link module:Collections.each}
+ * @alias forEachSeries
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each
+ * item in `coll`. The iteratee 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 iteratee. Invoked with (item, callback). If you need the
+ * index, use `eachOfSeries`.
+ * @param {Function} [callback] - A callback which is called when all
+ * `iteratee` functions have finished, or an error occurs. Invoked with (err).
+ */
+var eachSeries = doLimit(eachLimit$1, 1);
+
+/**
+ * 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.
+ *
+ * @name ensureAsync
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} fn - an async function, one that expects a node-style
+ * callback as its last argument.
+ * @returns {Function} Returns a wrapped function with the exact same call
+ * signature as the function passed in.
+ * @example
+ *
+ * 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);
+ */
+function ensureAsync(fn) {
+    return initialParams(function (args, callback) {
+        var sync = true;
+        args.push(function () {
+            var innerArgs = arguments;
+            if (sync) {
+                setImmediate$1(function () {
+                    callback.apply(null, innerArgs);
+                });
+            } else {
+                callback.apply(null, innerArgs);
+            }
+        });
+        fn.apply(this, args);
+        sync = false;
+    });
+}
+
+function notId(v) {
+    return !v;
+}
+
+/**
+ * Returns `true` if every element in `coll` satisfies an async test. If any
+ * iteratee call returns `false`, the main `callback` is immediately called.
+ *
+ * @name every
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias all
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in the
+ * collection in parallel. The iteratee is passed a `callback(err, truthValue)`
+ * which must be called with a  boolean argument once it has completed. Invoked
+ * with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result will be either `true` or `false`
+ * depending on the values of the async tests. Invoked with (err, result).
+ * @example
+ *
+ * async.every(['file1','file2','file3'], function(filePath, callback) {
+ *     fs.access(filePath, function(err) {
+ *         callback(null, !err)
+ *     });
+ * }, function(err, result) {
+ *     // if result is true then every file exists
+ * });
+ */
+var every = _createTester(eachOf, notId, notId);
+
+/**
+ * The same as [`every`]{@link module:Collections.every} but runs a maximum of `limit` async operations at a time.
+ *
+ * @name everyLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.every]{@link module:Collections.every}
+ * @alias allLimit
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A truth test to apply to each item in the
+ * collection in parallel. The iteratee is passed a `callback(err, truthValue)`
+ * which must be called with a  boolean argument once it has completed. Invoked
+ * with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result will be either `true` or `false`
+ * depending on the values of the async tests. Invoked with (err, result).
+ */
+var everyLimit = _createTester(eachOfLimit, notId, notId);
+
+/**
+ * The same as [`every`]{@link module:Collections.every} but runs only a single async operation at a time.
+ *
+ * @name everySeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.every]{@link module:Collections.every}
+ * @alias allSeries
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in the
+ * collection in parallel. The iteratee is passed a `callback(err, truthValue)`
+ * which must be called with a  boolean argument once it has completed. Invoked
+ * with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result will be either `true` or `false`
+ * depending on the values of the async tests. Invoked with (err, result).
+ */
+var everySeries = doLimit(everyLimit, 1);
+
+/**
+ * The base implementation of `_.property` without support for deep paths.
+ *
+ * @private
+ * @param {string} key The key of the property to get.
+ * @returns {Function} Returns the new accessor function.
+ */
+function baseProperty(key) {
+  return function(object) {
+    return object == null ? undefined : object[key];
+  };
+}
+
+function filterArray(eachfn, arr, iteratee, callback) {
+    var truthValues = new Array(arr.length);
+    eachfn(arr, function (x, index, callback) {
+        iteratee(x, function (err, v) {
+            truthValues[index] = !!v;
+            callback(err);
+        });
+    }, function (err) {
+        if (err) return callback(err);
+        var results = [];
+        for (var i = 0; i < arr.length; i++) {
+            if (truthValues[i]) results.push(arr[i]);
+        }
+        callback(null, results);
+    });
+}
+
+function filterGeneric(eachfn, coll, iteratee, callback) {
+    var results = [];
+    eachfn(coll, function (x, index, callback) {
+        iteratee(x, function (err, v) {
+            if (err) {
+                callback(err);
+            } else {
+                if (v) {
+                    results.push({ index: index, value: x });
+                }
+                callback();
+            }
+        });
+    }, function (err) {
+        if (err) {
+            callback(err);
+        } else {
+            callback(null, arrayMap(results.sort(function (a, b) {
+                return a.index - b.index;
+            }), baseProperty('value')));
+        }
+    });
+}
+
+function _filter(eachfn, coll, iteratee, callback) {
+    var filter = isArrayLike(coll) ? filterArray : filterGeneric;
+    filter(eachfn, coll, iteratee, callback || noop);
+}
+
+/**
+ * Returns a new array of all the values in `coll` which pass an async truth
+ * test. This operation is performed in parallel, but the results array will be
+ * in the same order as the original.
+ *
+ * @name filter
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias select
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results).
+ * @example
+ *
+ * async.filter(['file1','file2','file3'], function(filePath, callback) {
+ *     fs.access(filePath, function(err) {
+ *         callback(null, !err)
+ *     });
+ * }, function(err, results) {
+ *     // results now equals an array of the existing files
+ * });
+ */
+var filter = doParallel(_filter);
+
+/**
+ * The same as [`filter`]{@link module:Collections.filter} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name filterLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.filter]{@link module:Collections.filter}
+ * @alias selectLimit
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results).
+ */
+var filterLimit = doParallelLimit(_filter);
+
+/**
+ * The same as [`filter`]{@link module:Collections.filter} but runs only a single async operation at a time.
+ *
+ * @name filterSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.filter]{@link module:Collections.filter}
+ * @alias selectSeries
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results)
+ */
+var filterSeries = doLimit(filterLimit, 1);
+
+/**
+ * Calls the asynchronous function `fn` with a callback parameter that allows it
+ * to call itself again, in series, indefinitely.
+
+ * If an error is passed to the
+ * callback then `errback` is called with the error, and execution stops,
+ * otherwise it will never be called.
+ *
+ * @name forever
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Function} fn - a function to call repeatedly. Invoked with (next).
+ * @param {Function} [errback] - when `fn` passes an error to it's callback,
+ * this function will be called, and execution stops. Invoked with (err).
+ * @example
+ *
+ * async.forever(
+ *     function(next) {
+ *         // next is suitable for passing to things that need a callback(err [, whatever]);
+ *         // it will result in this function being called again.
+ *     },
+ *     function(err) {
+ *         // if next is called with a value in its first parameter, it will appear
+ *         // in here as 'err', and execution will stop.
+ *     }
+ * );
+ */
+function forever(fn, errback) {
+    var done = onlyOnce(errback || noop);
+    var task = ensureAsync(fn);
+
+    function next(err) {
+        if (err) return done(err);
+        task(next);
+    }
+    next();
+}
+
+/**
+ * Logs the result of an `async` function to the `console`. Only works in
+ * Node.js or in browsers that support `console.log` and `console.error` (such
+ * as FF and Chrome). If multiple arguments are returned from the async
+ * function, `console.log` is called on each argument in order.
+ *
+ * @name log
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} function - The function you want to eventually apply all
+ * arguments to.
+ * @param {...*} arguments... - Any number of arguments to apply to the function.
+ * @example
+ *
+ * // in a module
+ * var hello = function(name, callback) {
+ *     setTimeout(function() {
+ *         callback(null, 'hello ' + name);
+ *     }, 1000);
+ * };
+ *
+ * // in the node repl
+ * node> async.log(hello, 'world');
+ * 'hello world'
+ */
+var log = consoleFunc('log');
+
+/**
+ * The same as [`mapValues`]{@link module:Collections.mapValues} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name mapValuesLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.mapValues]{@link module:Collections.mapValues}
+ * @category Collection
+ * @param {Object} obj - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A function to apply to each value in `obj`.
+ * The iteratee is passed a `callback(err, transformed)` which must be called
+ * once it has completed with an error (which can be `null`) and a
+ * transformed value. Invoked with (value, key, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. `result` is a new object consisting
+ * of each key from `obj`, with each transformed value on the right-hand side.
+ * Invoked with (err, result).
+ */
+function mapValuesLimit(obj, limit, iteratee, callback) {
+    callback = once(callback || noop);
+    var newObj = {};
+    eachOfLimit(obj, limit, function (val, key, next) {
+        iteratee(val, key, function (err, result) {
+            if (err) return next(err);
+            newObj[key] = result;
+            next();
+        });
+    }, function (err) {
+        callback(err, newObj);
+    });
+}
+
+/**
+ * A relative of [`map`]{@link module:Collections.map}, designed for use with objects.
+ *
+ * Produces a new Object by mapping each value of `obj` through the `iteratee`
+ * function. The `iteratee` is called each `value` and `key` from `obj` and a
+ * callback for when it has finished processing. Each of these callbacks takes
+ * two arguments: an `error`, and the transformed item from `obj`. If `iteratee`
+ * passes an error to its callback, the main `callback` (for the `mapValues`
+ * function) is immediately called with the error.
+ *
+ * Note, the order of the keys in the result is not guaranteed.  The keys will
+ * be roughly in the order they complete, (but this is very engine-specific)
+ *
+ * @name mapValues
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @category Collection
+ * @param {Object} obj - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each value and key in
+ * `coll`. The iteratee is passed a `callback(err, transformed)` which must be
+ * called once it has completed with an error (which can be `null`) and a
+ * transformed value. Invoked with (value, key, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. `result` is a new object consisting
+ * of each key from `obj`, with each transformed value on the right-hand side.
+ * Invoked with (err, result).
+ * @example
+ *
+ * async.mapValues({
+ *     f1: 'file1',
+ *     f2: 'file2',
+ *     f3: 'file3'
+ * }, function (file, key, callback) {
+ *   fs.stat(file, callback);
+ * }, function(err, result) {
+ *     // result is now a map of stats for each file, e.g.
+ *     // {
+ *     //     f1: [stats for file1],
+ *     //     f2: [stats for file2],
+ *     //     f3: [stats for file3]
+ *     // }
+ * });
+ */
+
+var mapValues = doLimit(mapValuesLimit, Infinity);
+
+/**
+ * The same as [`mapValues`]{@link module:Collections.mapValues} but runs only a single async operation at a time.
+ *
+ * @name mapValuesSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.mapValues]{@link module:Collections.mapValues}
+ * @category Collection
+ * @param {Object} obj - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each value in `obj`.
+ * The iteratee is passed a `callback(err, transformed)` which must be called
+ * once it has completed with an error (which can be `null`) and a
+ * transformed value. Invoked with (value, key, callback).
+ * @param {Function} [callback] - A callback which is called when all `iteratee`
+ * functions have finished, or an error occurs. `result` is a new object consisting
+ * of each key from `obj`, with each transformed value on the right-hand side.
+ * Invoked with (err, result).
+ */
+var mapValuesSeries = doLimit(mapValuesLimit, 1);
+
+function has(obj, key) {
+    return key in obj;
+}
+
+/**
+ * Caches the results of an `async` function. When creating a hash to store
+ * function results against, the callback is omitted from the hash and an
+ * optional hash function can be used.
+ *
+ * If no hash function is specified, the first argument is used as a hash key,
+ * which may work reasonably if it is a string or a data type that converts to a
+ * distinct string. Note that objects and arrays will not behave reasonably.
+ * Neither will cases where the other arguments are significant. In such cases,
+ * specify your own hash function.
+ *
+ * The cache of results is exposed as the `memo` property of the function
+ * returned by `memoize`.
+ *
+ * @name memoize
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} fn - The function to proxy and cache results from.
+ * @param {Function} hasher - An optional function for generating a custom hash
+ * for storing results. It has all the arguments applied to it apart from the
+ * callback, and must be synchronous.
+ * @returns {Function} a memoized version of `fn`
+ * @example
+ *
+ * var slow_fn = function(name, callback) {
+ *     // do something
+ *     callback(null, result);
+ * };
+ * var fn = async.memoize(slow_fn);
+ *
+ * // fn can now be used as if it were slow_fn
+ * fn('some name', function() {
+ *     // callback
+ * });
+ */
+function memoize(fn, hasher) {
+    var memo = Object.create(null);
+    var queues = Object.create(null);
+    hasher = hasher || identity;
+    var memoized = initialParams(function memoized(args, callback) {
+        var key = hasher.apply(null, args);
+        if (has(memo, key)) {
+            setImmediate$1(function () {
+                callback.apply(null, memo[key]);
+            });
+        } else if (has(queues, key)) {
+            queues[key].push(callback);
+        } else {
+            queues[key] = [callback];
+            fn.apply(null, args.concat(rest(function (args) {
+                memo[key] = args;
+                var q = queues[key];
+                delete queues[key];
+                for (var i = 0, l = q.length; i < l; i++) {
+                    q[i].apply(null, args);
+                }
+            })));
+        }
+    });
+    memoized.memo = memo;
+    memoized.unmemoized = fn;
+    return memoized;
+}
+
+/**
+ * Calls `callback` on a later loop around the event loop. In Node.js this just
+ * calls `setImmediate`.  In the browser it will use `setImmediate` if
+ * available, otherwise `setTimeout(callback, 0)`, which means other higher
+ * priority events may precede the execution of `callback`.
+ *
+ * This is used internally for browser-compatibility purposes.
+ *
+ * @name nextTick
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @alias setImmediate
+ * @category Util
+ * @param {Function} callback - The function to call on a later loop around
+ * the event loop. Invoked with (args...).
+ * @param {...*} args... - any number of additional arguments to pass to the
+ * callback on the next tick.
+ * @example
+ *
+ * var call_order = [];
+ * async.nextTick(function() {
+ *     call_order.push('two');
+ *     // call_order now equals ['one','two']
+ * });
+ * call_order.push('one');
+ *
+ * async.setImmediate(function (a, b, c) {
+ *     // a, b, and c equal 1, 2, and 3
+ * }, 1, 2, 3);
+ */
+var _defer$1;
+
+if (hasNextTick) {
+    _defer$1 = process.nextTick;
+} else if (hasSetImmediate) {
+    _defer$1 = setImmediate;
+} else {
+    _defer$1 = fallback;
+}
+
+var nextTick = wrap(_defer$1);
+
+function _parallel(eachfn, tasks, callback) {
+    callback = callback || noop;
+    var results = isArrayLike(tasks) ? [] : {};
+
+    eachfn(tasks, function (task, key, callback) {
+        task(rest(function (err, args) {
+            if (args.length <= 1) {
+                args = args[0];
+            }
+            results[key] = args;
+            callback(err);
+        }));
+    }, function (err) {
+        callback(err, results);
+    });
+}
+
+/**
+ * Run the `tasks` collection of functions in parallel, without waiting until
+ * the previous function has completed. If any of the functions pass an error to
+ * its callback, the main `callback` is immediately called with the value of the
+ * error. Once the `tasks` have completed, the results are passed to the final
+ * `callback` as an array.
+ *
+ * **Note:** `parallel` is about kicking-off I/O tasks in parallel, not about
+ * parallel execution of code.  If your tasks do not use any timers or perform
+ * any I/O, they will actually be executed in series.  Any synchronous setup
+ * sections for each task will happen one after the other.  JavaScript remains
+ * single-threaded.
+ *
+ * It is also possible to use an object instead of an array. Each property will
+ * be run as a function and the results will be passed to the final `callback`
+ * as an object instead of an array. This can be a more readable way of handling
+ * results from {@link async.parallel}.
+ *
+ * @name parallel
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array|Iterable|Object} tasks - A collection 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.
+ * @param {Function} [callback] - An optional callback to run once all the
+ * functions have completed successfully. This function gets a results array
+ * (or object) containing all the result arguments passed to the task callbacks.
+ * Invoked with (err, results).
+ * @example
+ * async.parallel([
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'one');
+ *         }, 200);
+ *     },
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'two');
+ *         }, 100);
+ *     }
+ * ],
+ * // optional callback
+ * function(err, results) {
+ *     // the results array will equal ['one','two'] even though
+ *     // the second function had a shorter timeout.
+ * });
+ *
+ * // an example using an object instead of an array
+ * async.parallel({
+ *     one: function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 1);
+ *         }, 200);
+ *     },
+ *     two: function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 2);
+ *         }, 100);
+ *     }
+ * }, function(err, results) {
+ *     // results is now equals to: {one: 1, two: 2}
+ * });
+ */
+function parallelLimit(tasks, callback) {
+  _parallel(eachOf, tasks, callback);
+}
+
+/**
+ * The same as [`parallel`]{@link module:ControlFlow.parallel} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name parallelLimit
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.parallel]{@link module:ControlFlow.parallel}
+ * @category Control Flow
+ * @param {Array|Collection} tasks - A collection 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.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} [callback] - An optional callback to run once all the
+ * functions have completed successfully. This function gets a results array
+ * (or object) containing all the result arguments passed to the task callbacks.
+ * Invoked with (err, results).
+ */
+function parallelLimit$1(tasks, limit, callback) {
+  _parallel(_eachOfLimit(limit), tasks, callback);
+}
+
+/**
+ * A queue of tasks for the worker function to complete.
+ * @typedef {Object} QueueObject
+ * @memberOf module:ControlFlow
+ * @property {Function} length - a function returning the number of items
+ * waiting to be processed. Invoke with `queue.length()`.
+ * @property {boolean} started - a boolean indicating whether or not any
+ * items have been pushed and processed by the queue.
+ * @property {Function} running - a function returning the number of items
+ * currently being processed. Invoke with `queue.running()`.
+ * @property {Function} workersList - a function returning the array of items
+ * currently being processed. Invoke with `queue.workersList()`.
+ * @property {Function} idle - a function returning false if there are items
+ * waiting or being processed, or true if not. Invoke with `queue.idle()`.
+ * @property {number} concurrency - an integer for determining how many `worker`
+ * functions should be run in parallel. This property can be changed after a
+ * `queue` is created to alter the concurrency on-the-fly.
+ * @property {Function} push - 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. Invoke with `queue.push(task, [callback])`,
+ * @property {Function} unshift - add a new task to the front of the `queue`.
+ * Invoke with `queue.unshift(task, [callback])`.
+ * @property {Function} saturated - a callback that is called when the number of
+ * running workers hits the `concurrency` limit, and further tasks will be
+ * queued.
+ * @property {Function} unsaturated - a callback that is called when the number
+ * of running workers is less than the `concurrency` & `buffer` limits, and
+ * further tasks will not be queued.
+ * @property {number} buffer - A minimum threshold buffer in order to say that
+ * the `queue` is `unsaturated`.
+ * @property {Function} empty - a callback that is called when the last item
+ * from the `queue` is given to a `worker`.
+ * @property {Function} drain - a callback that is called when the last item
+ * from the `queue` has returned from the `worker`.
+ * @property {Function} error - a callback that is called when a task errors.
+ * Has the signature `function(error, task)`.
+ * @property {boolean} paused - a boolean for determining whether the queue is
+ * in a paused state.
+ * @property {Function} pause - a function that pauses the processing of tasks
+ * until `resume()` is called. Invoke with `queue.pause()`.
+ * @property {Function} resume - a function that resumes the processing of
+ * queued tasks when the queue is paused. Invoke with `queue.resume()`.
+ * @property {Function} kill - a function that removes the `drain` callback and
+ * empties remaining tasks from the queue forcing it to go idle. Invoke with `queue.kill()`.
+ */
+
+/**
+ * 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.
+ * Once a `worker` completes a `task`, that `task`'s callback is called.
+ *
+ * @name queue
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Function} worker - An asynchronous function for processing a queued
+ * 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()`. Invoked with
+ * (task, callback).
+ * @param {number} [concurrency=1] - An `integer` for determining how many
+ * `worker` functions should be run in parallel.  If omitted, the concurrency
+ * defaults to `1`.  If the concurrency is `0`, an error is thrown.
+ * @returns {module:ControlFlow.QueueObject} A queue object to manage the tasks. Callbacks can
+ * attached as certain properties to listen for specific events during the
+ * lifecycle of the queue.
+ * @example
+ *
+ * // create a queue object with concurrency 2
+ * var q = async.queue(function(task, callback) {
+ *     console.log('hello ' + task.name);
+ *     callback();
+ * }, 2);
+ *
+ * // assign a callback
+ * q.drain = function() {
+ *     console.log('all items have been processed');
+ * };
+ *
+ * // add some items to the queue
+ * q.push({name: 'foo'}, function(err) {
+ *     console.log('finished processing foo');
+ * });
+ * q.push({name: 'bar'}, function (err) {
+ *     console.log('finished processing bar');
+ * });
+ *
+ * // add some items to the queue (batch-wise)
+ * q.push([{name: 'baz'},{name: 'bay'},{name: 'bax'}], function(err) {
+ *     console.log('finished processing item');
+ * });
+ *
+ * // add some items to the front of the queue
+ * q.unshift({name: 'bar'}, function (err) {
+ *     console.log('finished processing bar');
+ * });
+ */
+var queue$1 = function (worker, concurrency) {
+  return queue(function (items, cb) {
+    worker(items[0], cb);
+  }, concurrency, 1);
+};
+
+/**
+ * The same as [async.queue]{@link module:ControlFlow.queue} only tasks are assigned a priority and
+ * completed in ascending priority order.
+ *
+ * @name priorityQueue
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.queue]{@link module:ControlFlow.queue}
+ * @category Control Flow
+ * @param {Function} worker - An asynchronous function for processing a queued
+ * 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()`. Invoked with
+ * (task, callback).
+ * @param {number} concurrency - An `integer` for determining how many `worker`
+ * functions should be run in parallel.  If omitted, the concurrency defaults to
+ * `1`.  If the concurrency is `0`, an error is thrown.
+ * @returns {module:ControlFlow.QueueObject} A priorityQueue object to manage the tasks. There are two
+ * differences between `queue` and `priorityQueue` objects:
+ * * `push(task, priority, [callback])` - `priority` should be a number. If an
+ *   array of `tasks` is given, all tasks will be assigned the same priority.
+ * * The `unshift` method was removed.
+ */
+var priorityQueue = function (worker, concurrency) {
+    // Start with a normal queue
+    var q = queue$1(worker, concurrency);
+
+    // Override push to accept second parameter representing priority
+    q.push = function (data, priority, callback) {
+        if (callback == null) callback = noop;
+        if (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 setImmediate$1(function () {
+                q.drain();
+            });
+        }
+
+        priority = priority || 0;
+        var nextNode = q._tasks.head;
+        while (nextNode && priority >= nextNode.priority) {
+            nextNode = nextNode.next;
+        }
+
+        for (var i = 0, l = data.length; i < l; i++) {
+            var item = {
+                data: data[i],
+                priority: priority,
+                callback: callback
+            };
+
+            if (nextNode) {
+                q._tasks.insertBefore(nextNode, item);
+            } else {
+                q._tasks.push(item);
+            }
+        }
+        setImmediate$1(q.process);
+    };
+
+    // Remove unshift function
+    delete q.unshift;
+
+    return q;
+};
+
+/**
+ * Runs the `tasks` array of functions in parallel, without waiting until the
+ * previous function has completed. Once any of the `tasks` complete or pass an
+ * error to its callback, the main `callback` is immediately called. It's
+ * equivalent to `Promise.race()`.
+ *
+ * @name race
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array} tasks - An array 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.
+ * @param {Function} callback - A callback to run once any of the functions have
+ * completed. This function gets an error or result from the first function that
+ * completed. Invoked with (err, result).
+ * @returns undefined
+ * @example
+ *
+ * async.race([
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'one');
+ *         }, 200);
+ *     },
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'two');
+ *         }, 100);
+ *     }
+ * ],
+ * // main callback
+ * function(err, result) {
+ *     // the result will be equal to 'two' as it finishes earlier
+ * });
+ */
+function race(tasks, callback) {
+    callback = once(callback || noop);
+    if (!isArray(tasks)) return callback(new TypeError('First argument to race must be an array of functions'));
+    if (!tasks.length) return callback();
+    for (var i = 0, l = tasks.length; i < l; i++) {
+        tasks[i](callback);
+    }
+}
+
+var slice = Array.prototype.slice;
+
+/**
+ * Same as [`reduce`]{@link module:Collections.reduce}, only operates on `array` in reverse order.
+ *
+ * @name reduceRight
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.reduce]{@link module:Collections.reduce}
+ * @alias foldr
+ * @category Collection
+ * @param {Array} array - A collection to iterate over.
+ * @param {*} memo - The initial state of the reduction.
+ * @param {Function} iteratee - A function applied to each item in the
+ * array to produce the next step in the reduction. The `iteratee` 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
+ * immediately called with the error. Invoked with (memo, item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result is the reduced value. Invoked with
+ * (err, result).
+ */
+function reduceRight(array, memo, iteratee, callback) {
+  var reversed = slice.call(array).reverse();
+  reduce(reversed, memo, iteratee, callback);
+}
+
+/**
+ * Wraps the function in another function that always returns data even when it
+ * errors.
+ *
+ * The object returned has either the property `error` or `value`.
+ *
+ * @name reflect
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} fn - The function you want to wrap
+ * @returns {Function} - A function that always passes null to it's callback as
+ * the error. The second argument to the callback will be an `object` with
+ * either an `error` or a `value` property.
+ * @example
+ *
+ * async.parallel([
+ *     async.reflect(function(callback) {
+ *         // do some stuff ...
+ *         callback(null, 'one');
+ *     }),
+ *     async.reflect(function(callback) {
+ *         // do some more stuff but error ...
+ *         callback('bad stuff happened');
+ *     }),
+ *     async.reflect(function(callback) {
+ *         // do some more stuff ...
+ *         callback(null, 'two');
+ *     })
+ * ],
+ * // optional callback
+ * function(err, results) {
+ *     // values
+ *     // results[0].value = 'one'
+ *     // results[1].error = 'bad stuff happened'
+ *     // results[2].value = 'two'
+ * });
+ */
+function reflect(fn) {
+    return initialParams(function reflectOn(args, reflectCallback) {
+        args.push(rest(function callback(err, cbArgs) {
+            if (err) {
+                reflectCallback(null, {
+                    error: err
+                });
+            } else {
+                var value = null;
+                if (cbArgs.length === 1) {
+                    value = cbArgs[0];
+                } else if (cbArgs.length > 1) {
+                    value = cbArgs;
+                }
+                reflectCallback(null, {
+                    value: value
+                });
+            }
+        }));
+
+        return fn.apply(this, args);
+    });
+}
+
+function reject$1(eachfn, arr, iteratee, callback) {
+    _filter(eachfn, arr, function (value, cb) {
+        iteratee(value, function (err, v) {
+            cb(err, !v);
+        });
+    }, callback);
+}
+
+/**
+ * The opposite of [`filter`]{@link module:Collections.filter}. Removes values that pass an `async` truth test.
+ *
+ * @name reject
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.filter]{@link module:Collections.filter}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results).
+ * @example
+ *
+ * async.reject(['file1','file2','file3'], function(filePath, callback) {
+ *     fs.access(filePath, function(err) {
+ *         callback(null, !err)
+ *     });
+ * }, function(err, results) {
+ *     // results now equals an array of missing files
+ *     createFiles(results);
+ * });
+ */
+var reject = doParallel(reject$1);
+
+/**
+ * A helper function that wraps an array or an object of functions with reflect.
+ *
+ * @name reflectAll
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @see [async.reflect]{@link module:Utils.reflect}
+ * @category Util
+ * @param {Array} tasks - The array of functions to wrap in `async.reflect`.
+ * @returns {Array} Returns an array of functions, each function wrapped in
+ * `async.reflect`
+ * @example
+ *
+ * let tasks = [
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'one');
+ *         }, 200);
+ *     },
+ *     function(callback) {
+ *         // do some more stuff but error ...
+ *         callback(new Error('bad stuff happened'));
+ *     },
+ *     function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'two');
+ *         }, 100);
+ *     }
+ * ];
+ *
+ * async.parallel(async.reflectAll(tasks),
+ * // optional callback
+ * function(err, results) {
+ *     // values
+ *     // results[0].value = 'one'
+ *     // results[1].error = Error('bad stuff happened')
+ *     // results[2].value = 'two'
+ * });
+ *
+ * // an example using an object instead of an array
+ * let tasks = {
+ *     one: function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'one');
+ *         }, 200);
+ *     },
+ *     two: function(callback) {
+ *         callback('two');
+ *     },
+ *     three: function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 'three');
+ *         }, 100);
+ *     }
+ * };
+ *
+ * async.parallel(async.reflectAll(tasks),
+ * // optional callback
+ * function(err, results) {
+ *     // values
+ *     // results.one.value = 'one'
+ *     // results.two.error = 'two'
+ *     // results.three.value = 'three'
+ * });
+ */
+function reflectAll(tasks) {
+    var results;
+    if (isArray(tasks)) {
+        results = arrayMap(tasks, reflect);
+    } else {
+        results = {};
+        baseForOwn(tasks, function (task, key) {
+            results[key] = reflect.call(this, task);
+        });
+    }
+    return results;
+}
+
+/**
+ * The same as [`reject`]{@link module:Collections.reject} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name rejectLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.reject]{@link module:Collections.reject}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results).
+ */
+var rejectLimit = doParallelLimit(reject$1);
+
+/**
+ * The same as [`reject`]{@link module:Collections.reject} but runs only a single async operation at a time.
+ *
+ * @name rejectSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.reject]{@link module:Collections.reject}
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in `coll`.
+ * The `iteratee` is passed a `callback(err, truthValue)`, which must be called
+ * with a boolean argument once it has completed. Invoked with (item, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Invoked with (err, results).
+ */
+var rejectSeries = doLimit(rejectLimit, 1);
+
+/**
+ * Creates a function that returns `value`.
+ *
+ * @static
+ * @memberOf _
+ * @since 2.4.0
+ * @category Util
+ * @param {*} value The value to return from the new function.
+ * @returns {Function} Returns the new constant function.
+ * @example
+ *
+ * var objects = _.times(2, _.constant({ 'a': 1 }));
+ *
+ * console.log(objects);
+ * // => [{ 'a': 1 }, { 'a': 1 }]
+ *
+ * console.log(objects[0] === objects[1]);
+ * // => true
+ */
+function constant$1(value) {
+  return function() {
+    return value;
+  };
+}
+
+/**
+ * Attempts to get a successful response from `task` no more than `times` times
+ * before returning an error. If the task is successful, the `callback` will be
+ * passed the result of the successful task. If all attempts fail, the callback
+ * will be passed the error and result (if any) of the final attempt.
+ *
+ * @name retry
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Object|number} [opts = {times: 5, interval: 0}| 5] - Can be either an
+ * object with `times` and `interval` or a number.
+ * * `times` - The number of attempts to make before giving up.  The default
+ *   is `5`.
+ * * `interval` - The time to wait between retries, in milliseconds.  The
+ *   default is `0`. The interval may also be specified as a function of the
+ *   retry count (see example).
+ * * `errorFilter` - An optional synchronous function that is invoked on
+ *   erroneous result. If it returns `true` the retry attempts will continue;
+ *   if the function returns `false` the retry flow is aborted with the current
+ *   attempt's error and result being returned to the final callback.
+ *   Invoked with (err).
+ * * If `opts` is a number, the number specifies the number of times to retry,
+ *   with the default interval of `0`.
+ * @param {Function} task - 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 the function's execution, and (2)
+ * a `results` object, containing the results of the previously executed
+ * functions (if nested inside another control flow). Invoked with
+ * (callback, results).
+ * @param {Function} [callback] - An optional callback which is called when the
+ * task has succeeded, or after the final failed attempt. It receives the `err`
+ * and `result` arguments of the last attempt at completing the `task`. Invoked
+ * with (err, results).
+ * @example
+ *
+ * // The `retry` function can be used as a stand-alone control flow by passing
+ * // a callback, as shown below:
+ *
+ * // try calling apiMethod 3 times
+ * async.retry(3, apiMethod, function(err, result) {
+ *     // do something with the result
+ * });
+ *
+ * // try calling apiMethod 3 times, waiting 200 ms between each retry
+ * async.retry({times: 3, interval: 200}, apiMethod, function(err, result) {
+ *     // do something with the result
+ * });
+ *
+ * // try calling apiMethod 10 times with exponential backoff
+ * // (i.e. intervals of 100, 200, 400, 800, 1600, ... milliseconds)
+ * async.retry({
+ *   times: 10,
+ *   interval: function(retryCount) {
+ *     return 50 * Math.pow(2, retryCount);
+ *   }
+ * }, apiMethod, function(err, result) {
+ *     // do something with the result
+ * });
+ *
+ * // try calling apiMethod the default 5 times no delay between each retry
+ * async.retry(apiMethod, function(err, result) {
+ *     // do something with the result
+ * });
+ *
+ * // try calling apiMethod only when error condition satisfies, all other
+ * // errors will abort the retry control flow and return to final callback
+ * async.retry({
+ *   errorFilter: function(err) {
+ *     return err.message === 'Temporary error'; // only retry on a specific error
+ *   }
+ * }, apiMethod, function(err, result) {
+ *     // do something with the result
+ * });
+ *
+ * // It can also be embedded within other control flow functions to retry
+ * // individual methods that are not as reliable, like this:
+ * async.auto({
+ *     users: api.getUsers.bind(api),
+ *     payments: async.retry(3, api.getPayments.bind(api))
+ * }, function(err, results) {
+ *     // do something with the results
+ * });
+ *
+ */
+function retry(opts, task, callback) {
+    var DEFAULT_TIMES = 5;
+    var DEFAULT_INTERVAL = 0;
+
+    var options = {
+        times: DEFAULT_TIMES,
+        intervalFunc: constant$1(DEFAULT_INTERVAL)
+    };
+
+    function parseTimes(acc, t) {
+        if (typeof t === 'object') {
+            acc.times = +t.times || DEFAULT_TIMES;
+
+            acc.intervalFunc = typeof t.interval === 'function' ? t.interval : constant$1(+t.interval || DEFAULT_INTERVAL);
+
+            acc.errorFilter = t.errorFilter;
+        } else if (typeof t === 'number' || typeof t === 'string') {
+            acc.times = +t || DEFAULT_TIMES;
+        } else {
+            throw new Error("Invalid arguments for async.retry");
+        }
+    }
+
+    if (arguments.length < 3 && typeof opts === 'function') {
+        callback = task || noop;
+        task = opts;
+    } else {
+        parseTimes(options, opts);
+        callback = callback || noop;
+    }
+
+    if (typeof task !== 'function') {
+        throw new Error("Invalid arguments for async.retry");
+    }
+
+    var attempt = 1;
+    function retryAttempt() {
+        task(function (err) {
+            if (err && attempt++ < options.times && (typeof options.errorFilter != 'function' || options.errorFilter(err))) {
+                setTimeout(retryAttempt, options.intervalFunc(attempt));
+            } else {
+                callback.apply(null, arguments);
+            }
+        });
+    }
+
+    retryAttempt();
+}
+
+/**
+ * A close relative of [`retry`]{@link module:ControlFlow.retry}.  This method wraps a task and makes it
+ * retryable, rather than immediately calling it with retries.
+ *
+ * @name retryable
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.retry]{@link module:ControlFlow.retry}
+ * @category Control Flow
+ * @param {Object|number} [opts = {times: 5, interval: 0}| 5] - optional
+ * options, exactly the same as from `retry`
+ * @param {Function} task - the asynchronous function to wrap
+ * @returns {Functions} The wrapped function, which when invoked, will retry on
+ * an error, based on the parameters specified in `opts`.
+ * @example
+ *
+ * async.auto({
+ *     dep1: async.retryable(3, getFromFlakyService),
+ *     process: ["dep1", async.retryable(3, function (results, cb) {
+ *         maybeProcessData(results.dep1, cb);
+ *     })]
+ * }, callback);
+ */
+var retryable = function (opts, task) {
+    if (!task) {
+        task = opts;
+        opts = null;
+    }
+    return initialParams(function (args, callback) {
+        function taskFn(cb) {
+            task.apply(null, args.concat(cb));
+        }
+
+        if (opts) retry(opts, taskFn, callback);else retry(taskFn, callback);
+    });
+};
+
+/**
+ * Run the functions in the `tasks` collection in series, each one running once
+ * the previous 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. Otherwise, `callback`
+ * receives an array of results when `tasks` have completed.
+ *
+ * It is also possible to use an object instead of an array. Each property will
+ * be run as a function, and the results will be passed to the final `callback`
+ * as an object instead of an array. This can be a more readable way of handling
+ *  results from {@link async.series}.
+ *
+ * **Note** that while many implementations preserve the order of object
+ * properties, the [ECMAScript Language Specification](http://www.ecma-international.org/ecma-262/5.1/#sec-8.6)
+ * explicitly states that
+ *
+ * > The mechanics and order of enumerating the properties is not specified.
+ *
+ * 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.
+ *
+ * @name series
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array|Iterable|Object} tasks - A collection containing functions to run, each
+ * function is passed a `callback(err, result)` it must call on completion with
+ * an error `err` (which can be `null`) and an optional `result` value.
+ * @param {Function} [callback] - An optional callback to run once all the
+ * functions have completed. This function gets a results array (or object)
+ * containing all the result arguments passed to the `task` callbacks. Invoked
+ * with (err, result).
+ * @example
+ * async.series([
+ *     function(callback) {
+ *         // do some stuff ...
+ *         callback(null, 'one');
+ *     },
+ *     function(callback) {
+ *         // do some more stuff ...
+ *         callback(null, 'two');
+ *     }
+ * ],
+ * // optional callback
+ * function(err, results) {
+ *     // results is now equal to ['one', 'two']
+ * });
+ *
+ * async.series({
+ *     one: function(callback) {
+ *         setTimeout(function() {
+ *             callback(null, 1);
+ *         }, 200);
+ *     },
+ *     two: function(callback){
+ *         setTimeout(function() {
+ *             callback(null, 2);
+ *         }, 100);
+ *     }
+ * }, function(err, results) {
+ *     // results is now equal to: {one: 1, two: 2}
+ * });
+ */
+function series(tasks, callback) {
+  _parallel(eachOfSeries, tasks, callback);
+}
+
+/**
+ * Returns `true` if at least one element in the `coll` satisfies an async test.
+ * If any iteratee call returns `true`, the main `callback` is immediately
+ * called.
+ *
+ * @name some
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias any
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in the array
+ * in parallel. The iteratee is passed a `callback(err, truthValue)` which must
+ * be called with a boolean argument once it has completed. Invoked with
+ * (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the iteratee functions have finished.
+ * Result will be either `true` or `false` depending on the values of the async
+ * tests. Invoked with (err, result).
+ * @example
+ *
+ * async.some(['file1','file2','file3'], function(filePath, callback) {
+ *     fs.access(filePath, function(err) {
+ *         callback(null, !err)
+ *     });
+ * }, function(err, result) {
+ *     // if result is true then at least one of the files exists
+ * });
+ */
+var some = _createTester(eachOf, Boolean, identity);
+
+/**
+ * The same as [`some`]{@link module:Collections.some} but runs a maximum of `limit` async operations at a time.
+ *
+ * @name someLimit
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.some]{@link module:Collections.some}
+ * @alias anyLimit
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - A truth test to apply to each item in the array
+ * in parallel. The iteratee is passed a `callback(err, truthValue)` which must
+ * be called with a boolean argument once it has completed. Invoked with
+ * (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the iteratee functions have finished.
+ * Result will be either `true` or `false` depending on the values of the async
+ * tests. Invoked with (err, result).
+ */
+var someLimit = _createTester(eachOfLimit, Boolean, identity);
+
+/**
+ * The same as [`some`]{@link module:Collections.some} but runs only a single async operation at a time.
+ *
+ * @name someSeries
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @see [async.some]{@link module:Collections.some}
+ * @alias anySeries
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A truth test to apply to each item in the array
+ * in parallel. The iteratee is passed a `callback(err, truthValue)` which must
+ * be called with a boolean argument once it has completed. Invoked with
+ * (item, callback).
+ * @param {Function} [callback] - A callback which is called as soon as any
+ * iteratee returns `true`, or after all the iteratee functions have finished.
+ * Result will be either `true` or `false` depending on the values of the async
+ * tests. Invoked with (err, result).
+ */
+var someSeries = doLimit(someLimit, 1);
+
+/**
+ * Sorts a list by the results of running each `coll` value through an async
+ * `iteratee`.
+ *
+ * @name sortBy
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {Function} iteratee - A function to apply to each item in `coll`.
+ * The iteratee is passed a `callback(err, sortValue)` which must be called once
+ * it has completed with an error (which can be `null`) and a value to use as
+ * the sort criteria. Invoked with (item, callback).
+ * @param {Function} callback - A callback which is called after all the
+ * `iteratee` functions have finished, or an error occurs. Results is the items
+ * from the original `coll` sorted by the values returned by the `iteratee`
+ * calls. Invoked with (err, results).
+ * @example
+ *
+ * async.sortBy(['file1','file2','file3'], function(file, callback) {
+ *     fs.stat(file, function(err, stats) {
+ *         callback(err, stats.mtime);
+ *     });
+ * }, function(err, results) {
+ *     // results is now the original array of files sorted by
+ *     // modified date
+ * });
+ *
+ * // By modifying the callback parameter the
+ * // sorting order can be influenced:
+ *
+ * // ascending order
+ * async.sortBy([1,9,3,5], function(x, callback) {
+ *     callback(null, x);
+ * }, function(err,result) {
+ *     // result callback
+ * });
+ *
+ * // descending order
+ * async.sortBy([1,9,3,5], function(x, callback) {
+ *     callback(null, x*-1);    //<- x*-1 instead of x, turns the order around
+ * }, function(err,result) {
+ *     // result callback
+ * });
+ */
+function sortBy(coll, iteratee, callback) {
+    map(coll, function (x, callback) {
+        iteratee(x, function (err, criteria) {
+            if (err) return callback(err);
+            callback(null, { value: x, criteria: criteria });
+        });
+    }, function (err, results) {
+        if (err) return callback(err);
+        callback(null, arrayMap(results.sort(comparator), baseProperty('value')));
+    });
+
+    function comparator(left, right) {
+        var a = left.criteria,
+            b = right.criteria;
+        return a < b ? -1 : a > b ? 1 : 0;
+    }
+}
+
+/**
+ * Sets a time limit on an asynchronous function. If the function does not call
+ * its callback within the specified milliseconds, it will be called with a
+ * timeout error. The code property for the error object will be `'ETIMEDOUT'`.
+ *
+ * @name timeout
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @category Util
+ * @param {Function} asyncFn - The asynchronous function you want to set the
+ * time limit.
+ * @param {number} milliseconds - The specified time limit.
+ * @param {*} [info] - Any variable you want attached (`string`, `object`, etc)
+ * to timeout Error for more information..
+ * @returns {Function} Returns a wrapped function that can be used with any of
+ * the control flow functions. Invoke this function with the same
+ * parameters as you would `asyncFunc`.
+ * @example
+ *
+ * function myFunction(foo, callback) {
+ *     doAsyncTask(foo, function(err, data) {
+ *         // handle errors
+ *         if (err) return callback(err);
+ *
+ *         // do some stuff ...
+ *
+ *         // return processed data
+ *         return callback(null, data);
+ *     });
+ * }
+ *
+ * var wrapped = async.timeout(myFunction, 1000);
+ *
+ * // call `wrapped` as you would `myFunction`
+ * wrapped({ bar: 'bar' }, function(err, data) {
+ *     // if `myFunction` takes < 1000 ms to execute, `err`
+ *     // and `data` will have their expected values
+ *
+ *     // else `err` will be an Error with the code 'ETIMEDOUT'
+ * });
+ */
+function timeout(asyncFn, milliseconds, info) {
+    var originalCallback, timer;
+    var timedOut = false;
+
+    function injectedCallback() {
+        if (!timedOut) {
+            originalCallback.apply(null, arguments);
+            clearTimeout(timer);
+        }
+    }
+
+    function timeoutCallback() {
+        var name = asyncFn.name || 'anonymous';
+        var error = new Error('Callback function "' + name + '" timed out.');
+        error.code = 'ETIMEDOUT';
+        if (info) {
+            error.info = info;
+        }
+        timedOut = true;
+        originalCallback(error);
+    }
+
+    return initialParams(function (args, origCallback) {
+        originalCallback = origCallback;
+        // setup timer and call original function
+        timer = setTimeout(timeoutCallback, milliseconds);
+        asyncFn.apply(null, args.concat(injectedCallback));
+    });
+}
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeCeil = Math.ceil;
+var nativeMax$1 = Math.max;
+
+/**
+ * The base implementation of `_.range` and `_.rangeRight` which doesn't
+ * coerce arguments.
+ *
+ * @private
+ * @param {number} start The start of the range.
+ * @param {number} end The end of the range.
+ * @param {number} step The value to increment or decrement by.
+ * @param {boolean} [fromRight] Specify iterating from right to left.
+ * @returns {Array} Returns the range of numbers.
+ */
+function baseRange(start, end, step, fromRight) {
+  var index = -1,
+      length = nativeMax$1(nativeCeil((end - start) / (step || 1)), 0),
+      result = Array(length);
+
+  while (length--) {
+    result[fromRight ? length : ++index] = start;
+    start += step;
+  }
+  return result;
+}
+
+/**
+ * The same as [times]{@link module:ControlFlow.times} but runs a maximum of `limit` async operations at a
+ * time.
+ *
+ * @name timesLimit
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.times]{@link module:ControlFlow.times}
+ * @category Control Flow
+ * @param {number} count - The number of times to run the function.
+ * @param {number} limit - The maximum number of async operations at a time.
+ * @param {Function} iteratee - The function to call `n` times. Invoked with the
+ * iteration index and a callback (n, next).
+ * @param {Function} callback - see [async.map]{@link module:Collections.map}.
+ */
+function timeLimit(count, limit, iteratee, callback) {
+  mapLimit(baseRange(0, count, 1), limit, iteratee, callback);
+}
+
+/**
+ * Calls the `iteratee` function `n` times, and accumulates results in the same
+ * manner you would use with [map]{@link module:Collections.map}.
+ *
+ * @name times
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.map]{@link module:Collections.map}
+ * @category Control Flow
+ * @param {number} n - The number of times to run the function.
+ * @param {Function} iteratee - The function to call `n` times. Invoked with the
+ * iteration index and a callback (n, next).
+ * @param {Function} callback - see {@link module:Collections.map}.
+ * @example
+ *
+ * // Pretend this is some complicated async factory
+ * var createUser = function(id, callback) {
+ *     callback(null, {
+ *         id: 'user' + id
+ *     });
+ * };
+ *
+ * // generate 5 users
+ * async.times(5, function(n, next) {
+ *     createUser(n, function(err, user) {
+ *         next(err, user);
+ *     });
+ * }, function(err, users) {
+ *     // we should now have 5 users
+ * });
+ */
+var times = doLimit(timeLimit, Infinity);
+
+/**
+ * The same as [times]{@link module:ControlFlow.times} but runs only a single async operation at a time.
+ *
+ * @name timesSeries
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.times]{@link module:ControlFlow.times}
+ * @category Control Flow
+ * @param {number} n - The number of times to run the function.
+ * @param {Function} iteratee - The function to call `n` times. Invoked with the
+ * iteration index and a callback (n, next).
+ * @param {Function} callback - see {@link module:Collections.map}.
+ */
+var timesSeries = doLimit(timeLimit, 1);
+
+/**
+ * A relative of `reduce`.  Takes an Object or Array, and iterates over each
+ * element in series, each step potentially mutating an `accumulator` value.
+ * The type of the accumulator defaults to the type of collection passed in.
+ *
+ * @name transform
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {*} [accumulator] - The initial state of the transform.  If omitted,
+ * it will default to an empty Object or Array, depending on the type of `coll`
+ * @param {Function} iteratee - A function applied to each item in the
+ * collection that potentially modifies the accumulator. The `iteratee` is
+ * passed a `callback(err)` which accepts an optional error as its first
+ * argument. If an error is passed to the callback, the transform is stopped
+ * and the main `callback` is immediately called with the error.
+ * Invoked with (accumulator, item, key, callback).
+ * @param {Function} [callback] - A callback which is called after all the
+ * `iteratee` functions have finished. Result is the transformed accumulator.
+ * Invoked with (err, result).
+ * @example
+ *
+ * async.transform([1,2,3], function(acc, item, index, callback) {
+ *     // pointless async:
+ *     process.nextTick(function() {
+ *         acc.push(item * 2)
+ *         callback(null)
+ *     });
+ * }, function(err, result) {
+ *     // result is now equal to [2, 4, 6]
+ * });
+ *
+ * @example
+ *
+ * async.transform({a: 1, b: 2, c: 3}, function (obj, val, key, callback) {
+ *     setImmediate(function () {
+ *         obj[key] = val * 2;
+ *         callback();
+ *     })
+ * }, function (err, result) {
+ *     // result is equal to {a: 2, b: 4, c: 6}
+ * })
+ */
+function transform(coll, accumulator, iteratee, callback) {
+    if (arguments.length === 3) {
+        callback = iteratee;
+        iteratee = accumulator;
+        accumulator = isArray(coll) ? [] : {};
+    }
+    callback = once(callback || noop);
+
+    eachOf(coll, function (v, k, cb) {
+        iteratee(accumulator, v, k, cb);
+    }, function (err) {
+        callback(err, accumulator);
+    });
+}
+
+/**
+ * Undoes a [memoize]{@link module:Utils.memoize}d function, reverting it to the original,
+ * unmemoized form. Handy for testing.
+ *
+ * @name unmemoize
+ * @static
+ * @memberOf module:Utils
+ * @method
+ * @see [async.memoize]{@link module:Utils.memoize}
+ * @category Util
+ * @param {Function} fn - the memoized function
+ * @returns {Function} a function that calls the original unmemoized function
+ */
+function unmemoize(fn) {
+    return function () {
+        return (fn.unmemoized || fn).apply(null, arguments);
+    };
+}
+
+/**
+ * Repeatedly call `iteratee`, while `test` returns `true`. Calls `callback` when
+ * stopped, or an error occurs.
+ *
+ * @name whilst
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Function} test - synchronous truth test to perform before each
+ * execution of `iteratee`. Invoked with ().
+ * @param {Function} iteratee - 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 optional `err` argument. Invoked with (callback).
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has failed and repeated execution of `iteratee` has stopped. `callback`
+ * will be passed an error and any arguments passed to the final `iteratee`'s
+ * callback. Invoked with (err, [results]);
+ * @returns undefined
+ * @example
+ *
+ * var count = 0;
+ * async.whilst(
+ *     function() { return count < 5; },
+ *     function(callback) {
+ *         count++;
+ *         setTimeout(function() {
+ *             callback(null, count);
+ *         }, 1000);
+ *     },
+ *     function (err, n) {
+ *         // 5 seconds have passed, n = 5
+ *     }
+ * );
+ */
+function whilst(test, iteratee, callback) {
+    callback = onlyOnce(callback || noop);
+    if (!test()) return callback(null);
+    var next = rest(function (err, args) {
+        if (err) return callback(err);
+        if (test()) return iteratee(next);
+        callback.apply(null, [null].concat(args));
+    });
+    iteratee(next);
+}
+
+/**
+ * Repeatedly call `fn` until `test` returns `true`. Calls `callback` when
+ * stopped, or an error occurs. `callback` will be passed an error and any
+ * arguments passed to the final `fn`'s callback.
+ *
+ * The inverse of [whilst]{@link module:ControlFlow.whilst}.
+ *
+ * @name until
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @see [async.whilst]{@link module:ControlFlow.whilst}
+ * @category Control Flow
+ * @param {Function} test - synchronous truth test to perform before each
+ * execution of `fn`. Invoked with ().
+ * @param {Function} fn - A function which is called each time `test` fails.
+ * The function is passed a `callback(err)`, which must be called once it has
+ * completed with an optional `err` argument. Invoked with (callback).
+ * @param {Function} [callback] - A callback which is called after the test
+ * function has passed and repeated execution of `fn` has stopped. `callback`
+ * will be passed an error and any arguments passed to the final `fn`'s
+ * callback. Invoked with (err, [results]);
+ */
+function until(test, fn, callback) {
+    whilst(function () {
+        return !test.apply(this, arguments);
+    }, fn, callback);
+}
+
+/**
+ * Runs the `tasks` array of functions in series, each passing their results to
+ * the next in the array. However, if any of the `tasks` pass an error to their
+ * own callback, the next function is not executed, and the main `callback` is
+ * immediately called with the error.
+ *
+ * @name waterfall
+ * @static
+ * @memberOf module:ControlFlow
+ * @method
+ * @category Control Flow
+ * @param {Array} 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 passed as arguments in order to the next task.
+ * @param {Function} [callback] - An optional callback to run once all the
+ * functions have completed. This will be passed the results of the last task's
+ * callback. Invoked with (err, [results]).
+ * @returns undefined
+ * @example
+ *
+ * async.waterfall([
+ *     function(callback) {
+ *         callback(null, 'one', 'two');
+ *     },
+ *     function(arg1, arg2, callback) {
+ *         // arg1 now equals 'one' and arg2 now equals 'two'
+ *         callback(null, 'three');
+ *     },
+ *     function(arg1, callback) {
+ *         // arg1 now equals 'three'
+ *         callback(null, 'done');
+ *     }
+ * ], function (err, result) {
+ *     // result now equals 'done'
+ * });
+ *
+ * // Or, with named functions:
+ * async.waterfall([
+ *     myFirstFunction,
+ *     mySecondFunction,
+ *     myLastFunction,
+ * ], function (err, result) {
+ *     // result now equals 'done'
+ * });
+ * function myFirstFunction(callback) {
+ *     callback(null, 'one', 'two');
+ * }
+ * function mySecondFunction(arg1, arg2, callback) {
+ *     // arg1 now equals 'one' and arg2 now equals 'two'
+ *     callback(null, 'three');
+ * }
+ * function myLastFunction(arg1, callback) {
+ *     // arg1 now equals 'three'
+ *     callback(null, 'done');
+ * }
+ */
+var waterfall = function (tasks, callback) {
+    callback = once(callback || noop);
+    if (!isArray(tasks)) return callback(new Error('First argument to waterfall must be an array of functions'));
+    if (!tasks.length) return callback();
+    var taskIndex = 0;
+
+    function nextTask(args) {
+        if (taskIndex === tasks.length) {
+            return callback.apply(null, [null].concat(args));
+        }
+
+        var taskCallback = onlyOnce(rest(function (err, args) {
+            if (err) {
+                return callback.apply(null, [err].concat(args));
+            }
+            nextTask(args);
+        }));
+
+        args.push(taskCallback);
+
+        var task = tasks[taskIndex++];
+        task.apply(null, args);
+    }
+
+    nextTask([]);
+};
+
+/**
+ * Async is a utility module which provides straight-forward, powerful functions
+ * for working with asynchronous JavaScript. Although originally designed for
+ * use with [Node.js](http://nodejs.org) and installable via
+ * `npm install --save async`, it can also be used directly in the browser.
+ * @module async
+ */
+
+/**
+ * A collection of `async` functions for manipulating collections, such as
+ * arrays and objects.
+ * @module Collections
+ */
+
+/**
+ * A collection of `async` functions for controlling the flow through a script.
+ * @module ControlFlow
+ */
+
+/**
+ * A collection of `async` utility functions.
+ * @module Utils
+ */
+var index = {
+  applyEach: applyEach,
+  applyEachSeries: applyEachSeries,
+  apply: apply$2,
+  asyncify: asyncify,
+  auto: auto,
+  autoInject: autoInject,
+  cargo: cargo,
+  compose: compose,
+  concat: concat,
+  concatSeries: concatSeries,
+  constant: constant,
+  detect: detect,
+  detectLimit: detectLimit,
+  detectSeries: detectSeries,
+  dir: dir,
+  doDuring: doDuring,
+  doUntil: doUntil,
+  doWhilst: doWhilst,
+  during: during,
+  each: eachLimit,
+  eachLimit: eachLimit$1,
+  eachOf: eachOf,
+  eachOfLimit: eachOfLimit,
+  eachOfSeries: eachOfSeries,
+  eachSeries: eachSeries,
+  ensureAsync: ensureAsync,
+  every: every,
+  everyLimit: everyLimit,
+  everySeries: everySeries,
+  filter: filter,
+  filterLimit: filterLimit,
+  filterSeries: filterSeries,
+  forever: forever,
+  log: log,
+  map: map,
+  mapLimit: mapLimit,
+  mapSeries: mapSeries,
+  mapValues: mapValues,
+  mapValuesLimit: mapValuesLimit,
+  mapValuesSeries: mapValuesSeries,
+  memoize: memoize,
+  nextTick: nextTick,
+  parallel: parallelLimit,
+  parallelLimit: parallelLimit$1,
+  priorityQueue: priorityQueue,
+  queue: queue$1,
+  race: race,
+  reduce: reduce,
+  reduceRight: reduceRight,
+  reflect: reflect,
+  reflectAll: reflectAll,
+  reject: reject,
+  rejectLimit: rejectLimit,
+  rejectSeries: rejectSeries,
+  retry: retry,
+  retryable: retryable,
+  seq: seq$1,
+  series: series,
+  setImmediate: setImmediate$1,
+  some: some,
+  someLimit: someLimit,
+  someSeries: someSeries,
+  sortBy: sortBy,
+  timeout: timeout,
+  times: times,
+  timesLimit: timeLimit,
+  timesSeries: timesSeries,
+  transform: transform,
+  unmemoize: unmemoize,
+  until: until,
+  waterfall: waterfall,
+  whilst: whilst,
+
+  // aliases
+  all: every,
+  any: some,
+  forEach: eachLimit,
+  forEachSeries: eachSeries,
+  forEachLimit: eachLimit$1,
+  forEachOf: eachOf,
+  forEachOfSeries: eachOfSeries,
+  forEachOfLimit: eachOfLimit,
+  inject: reduce,
+  foldl: reduce,
+  foldr: reduceRight,
+  select: filter,
+  selectLimit: filterLimit,
+  selectSeries: filterSeries,
+  wrapSync: asyncify
+};
+
+exports['default'] = index;
+exports.applyEach = applyEach;
+exports.applyEachSeries = applyEachSeries;
+exports.apply = apply$2;
+exports.asyncify = asyncify;
+exports.auto = auto;
+exports.autoInject = autoInject;
+exports.cargo = cargo;
+exports.compose = compose;
+exports.concat = concat;
+exports.concatSeries = concatSeries;
+exports.constant = constant;
+exports.detect = detect;
+exports.detectLimit = detectLimit;
+exports.detectSeries = detectSeries;
+exports.dir = dir;
+exports.doDuring = doDuring;
+exports.doUntil = doUntil;
+exports.doWhilst = doWhilst;
+exports.during = during;
+exports.each = eachLimit;
+exports.eachLimit = eachLimit$1;
+exports.eachOf = eachOf;
+exports.eachOfLimit = eachOfLimit;
+exports.eachOfSeries = eachOfSeries;
+exports.eachSeries = eachSeries;
+exports.ensureAsync = ensureAsync;
+exports.every = every;
+exports.everyLimit = everyLimit;
+exports.everySeries = everySeries;
+exports.filter = filter;
+exports.filterLimit = filterLimit;
+exports.filterSeries = filterSeries;
+exports.forever = forever;
+exports.log = log;
+exports.map = map;
+exports.mapLimit = mapLimit;
+exports.mapSeries = mapSeries;
+exports.mapValues = mapValues;
+exports.mapValuesLimit = mapValuesLimit;
+exports.mapValuesSeries = mapValuesSeries;
+exports.memoize = memoize;
+exports.nextTick = nextTick;
+exports.parallel = parallelLimit;
+exports.parallelLimit = parallelLimit$1;
+exports.priorityQueue = priorityQueue;
+exports.queue = queue$1;
+exports.race = race;
+exports.reduce = reduce;
+exports.reduceRight = reduceRight;
+exports.reflect = reflect;
+exports.reflectAll = reflectAll;
+exports.reject = reject;
+exports.rejectLimit = rejectLimit;
+exports.rejectSeries = rejectSeries;
+exports.retry = retry;
+exports.retryable = retryable;
+exports.seq = seq$1;
+exports.series = series;
+exports.setImmediate = setImmediate$1;
+exports.some = some;
+exports.someLimit = someLimit;
+exports.someSeries = someSeries;
+exports.sortBy = sortBy;
+exports.timeout = timeout;
+exports.times = times;
+exports.timesLimit = timeLimit;
+exports.timesSeries = timesSeries;
+exports.transform = transform;
+exports.unmemoize = unmemoize;
+exports.until = until;
+exports.waterfall = waterfall;
+exports.whilst = whilst;
+exports.all = every;
+exports.allLimit = everyLimit;
+exports.allSeries = everySeries;
+exports.any = some;
+exports.anyLimit = someLimit;
+exports.anySeries = someSeries;
+exports.find = detect;
+exports.findLimit = detectLimit;
+exports.findSeries = detectSeries;
+exports.forEach = eachLimit;
+exports.forEachSeries = eachSeries;
+exports.forEachLimit = eachLimit$1;
+exports.forEachOf = eachOf;
+exports.forEachOfSeries = eachOfSeries;
+exports.forEachOfLimit = eachOfLimit;
+exports.inject = reduce;
+exports.foldl = reduce;
+exports.foldr = reduceRight;
+exports.select = filter;
+exports.selectLimit = filterLimit;
+exports.selectSeries = filterSeries;
+exports.wrapSync = asyncify;
+
+Object.defineProperty(exports, '__esModule', { value: true });
+
+})));
diff --git a/RPCTests/modules/startnode.js b/RPCTests/modules/startnode.js
new file mode 100644
index 000000000..f0877b065
--- /dev/null
+++ b/RPCTests/modules/startnode.js
@@ -0,0 +1,27 @@
+function startNode (nodeExec, dataDir, genesisPath, listeningPort) 
+{
+  var spawn = require('child_process').spawn
+  var options = [
+    '--private', 'privatechain',
+    '-d', dataDir,
+    '--config', genesisPath,
+    '--ipcpath', dataDir + '/geth.ipc',
+    '--ipc',
+    '--listen', listeningPort,
+    '--test'
+  ]
+  console.log('starting node')
+  console.log(nodeExec + ' ' + options.join(' '))
+  var node = spawn(nodeExec, options)
+  node.stdout.on('data', (data) => {
+    console.log(`stdout: ${data}`)
+  })
+  node.stderr.on('data', (data) => {
+    console.log(`stderr: ${data}`)
+  })
+  node.on('close', (code) => {
+    console.log(`child process exited with code ${code}`)
+  })
+}
+
+module.exports = startNode
diff --git a/RPCTests/modules/utils.js b/RPCTests/modules/utils.js
new file mode 100644
index 000000000..763c9894e
--- /dev/null
+++ b/RPCTests/modules/utils.js
@@ -0,0 +1,44 @@
+const fs = require('fs');
+function sleep(ms) {
+   return new Promise(resolve => setTimeout(resolve, ms));
+ }
+
+module.exports = {
+
+ sleep: function sleep(ms) {
+   return new Promise(resolve => setTimeout(resolve, ms));
+ },
+
+
+ mkdir: function mkdir(path, callback, arg) {
+  try {
+    fs.mkdirSync(path);
+  } catch(e) {
+    if ( e.code != 'EEXIST' ) throw e;
+  }
+  callback(arg);
+ },
+
+ rmdir: function rmdir(path) {
+  if( fs.existsSync(path) ) {
+    fs.readdirSync(path).forEach(function(file,index){
+      var curPath = path + "/" + file;
+      if(fs.lstatSync(curPath).isDirectory()) { // recurse
+        rmdir(curPath);
+      } else { // delete file
+        fs.unlinkSync(curPath);
+      }
+    });
+    fs.rmdirSync(path);
+  }
+ },
+
+ readFile: function readFile(path, callback) {
+    fs.readFile(path, 'utf8',  (err, data) => { callback (err, data) });
+ },
+
+ writeFile: function writeFile(path, data) {
+   fs.writeFile(path, data, (err) => { if (err) throw err;});
+ }
+}
+